Sample records for adding polyethylene glycol

  1. Bacterial Utilization of Ether Glycols

    PubMed Central

    Fincher, Edward L.; Payne, W. J.

    1962-01-01

    A soil bacterium capable of using oligo- and polyethylene glycols and ether alcohols as sole sources of carbon for aerobic growth was isolated. The effects of substituent groups added to the ether bonds on the acceptability of the compounds as substrates were studied. Mechanisms for the incorporation of two-carbon compounds were demonstrated by the observation that acetate, glyoxylate, ethylene glycol, and a number of the tricarboxylic acid cycle intermediates served as growth substrates in minimal media. The rate of oxidation of the short-chained ethylene glycols by adapted resting cells varied directly with increasing numbers of two-carbon units in the chains from one to four. The amount of oxygen consumed per carbon atom of oligo- and polyethylene glycols was 100% of theoretical, but only 67% of theoretical for ethylene glycol. Resting cells oxidized oligo- and polyethylene glycols with 2 to 600 two-carbon units in the chains. Longer chained polyethylene glycols (up to 6,000) were oxidized at a very slow rate by these cells. Dehydrogenation of triethylene glycol by adapted cells was observed, coupling the reaction with methylene blue reduction. PMID:13945208

  2. Substitution of blood coagulation factor X-binding to Ad5 by position-specific PEGylation: Preventing vector clearance and preserving infectivity.

    PubMed

    Krutzke, L; Prill, J M; Engler, T; Schmidt, C Q; Xu, Z; Byrnes, A P; Simmet, T; Kreppel, F

    2016-08-10

    The biodistribution of adenovirus type 5 (Ad5) vector particles is heavily influenced by interaction of the particles with plasma proteins, including coagulation factor X (FX), which binds specifically to the major Ad5 capsid protein hexon. FX mediates hepatocyte transduction by intravenously-injected Ad5 vectors and shields vector particles from neutralization by natural antibodies and complement. In mice, mutant Ad5 vectors that are ablated for FX-binding become detargeted from hepatocytes, which is desirable for certain applications, but unfortunately such FX-nonbinding vectors also become sensitive to neutralization by mouse plasma proteins. To improve the properties of Ad5 vectors for systemic delivery, we developed a strategy to replace the natural FX shield by a site-specific chemical polyethylene glycol shield. Coupling of polyethylene glycol to a specific site in hexon hypervariable region 1 yielded vector particles that were protected from neutralization by natural antibodies and complement although they were unable to bind FX. These vector particles evaded macrophages in vitro and showed significantly improved pharmacokinetics and hepatocyte transduction in vivo. Thus, site-specific shielding of Ad5 vectors with polyethylene glycol rendered vectors FX-independent and greatly improved their properties for systemic gene therapy. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Additives aided composting of green waste: effects on organic matter degradation, compost maturity, and quality of the finished compost.

    PubMed

    Gabhane, Jagdish; William, S P M Prince; Bidyadhar, Rajnikant; Bhilawe, Priya; Anand, Duraisamy; Vaidya, Atul N; Wate, Satish R

    2012-06-01

    The effect of various additives such as fly ash, phosphogypsum, jaggery, lime, and polyethylene glycol on green waste composting was investigated through assessing their influence on microbial growth, enzymatic activities, organic matter degradation, bulk density, quality of finished compost including gradation test, heavy metal analysis, etc. A perusal of results showed that addition of jaggery and polyethylene glycol were helpful to facilitate composting process as they significantly influenced the growth of microbes and cellulase activity. The quality of finished compost prepared from jaggery and polyethylene glycol added treatments were superior to other composts, wherein reduction in C/N ratio was more than 8% in jaggery treatment. All other parameters of compost quality including gradation test also favored jaggery and polyethylene glycol as the best additives for green waste composting. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. ANTIMICROBIAL EFFECT OF INTRACANAL SUBSTANCES

    PubMed Central

    Carreira, Cláudia de Moura; dos Santos, Silvana Soléo Ferreira; Jorge, Antônio Olavo Cardoso; Lage-Marques, José Luiz

    2007-01-01

    In some situations, endodontic infections do not respond to therapeutic protocol. In these cases, it is suggested the administration of an alternative intracanal medication that presents a wide spectrum of action and has an in-depth effect on the root canal system. The purpose of this study was to assess the antimicrobial action of ciprofloxacin, metronidazole and polyethylene glycol and natrosol vehicles with different associations and concentrations. The minimum inhibitory concentration (MIC) was determined by using the agar dilution method. The culture media (Müller-Hinton agar) were prepared containing antimicrobial agents at multiple two-fold dilutions of 0.25 to 16 µg/mL, and with the vehicles at the concentrations of 50, 45, 40, 35, 30 and 25%. Twenty-three microbial strains were selected for the study. Metronidazole was not capable of eliminating any of the tested microorganisms. The association of ciprofloxacin with metronidazole resulted in a reduction of the MIC. The vehicle polyethylene glycol inhibited the growth of 100% of the tested strains, while natrosol inhibited 18% of the strains. Ciprofloxacin formulations with polyethylene glycol presented better effects than those of formulations to which metronidazole was added. It was possible to conclude that ciprofloxacin presented antimicrobial action against all tested bacterial strains, and its association with metronidazole was synergic. The vehicle polyethylene glycol showed antimicrobial effect and the ciprofloxacin/polyethylene glycol association was the most effective combination for reducing the tested bacteria and yeasts. PMID:19089178

  5. Additional of polyethylene glycol on the preparation of LaPO4:Eu3+ phosphor

    NASA Astrophysics Data System (ADS)

    Panatarani, Camellia; Joni, I. Made

    2013-09-01

    Solution phase method was used to synthesis nanocrystal LaPO4:Eu3+. Polyethylene glycol with vary molecular weight (MW) was added to allow an exothermic reaction to get a high crystalinity of LaPO4:Eu3+. The x-ray pattern of as prepared LaPO4 was obtained by using an X'pert PANalytical diffractometer with CuKα radiation (λ = 1.5406 Å) and the photoluminescent measurement spectra is obtained by using Fluorescence Spectrometer LS55, Perkin Elmer. The additional of various MW of polyethylene glycol into the precursor solution of LaPO4:Eu3+ affected the crystal structure and luminescent properties. Higher MW of PEG depressing the luminescent spectra. The emission origin from 5D0-7F4 transition vanished by additional 500,000 and 2,000,000 MW of PEG.

  6. Orange juice intake reduces patient discomfort and is effective for bowel cleansing with polyethylene glycol during bowel preparation.

    PubMed

    Choi, Hong Seok; Shim, Chan Sup; Kim, Gyu Won; Kim, Jung Seok; Lee, Sun-Young; Sung, In-Kyung; Park, Hyung Seok; Kim, Jeong Hwan

    2014-10-01

    Many patients report discomfort because of the unpleasant taste of bowel preparation solutions. This study aimed to determine whether adding orange juice to 2 L of polyethylene glycol plus ascorbic acid is effective for reducing patient discomfort and improving palatability during bowel preparation. This was a single-blinded, randomized controlled trial. The study was conducted at a tertiary referral hospital and a generalized hospital. Consecutive outpatients and inpatients were randomly allocated to drink 2 L of polyethylene glycol-ascorbic acid or 2 L of polyethylene glycol-ascorbic acid with orange juice in a single dose or a split dose. Tolerability, palatability score, willingness, and related adverse events were investigated by questionnaires. Bowel cleansing was rated using the Aronchick scale. Each score was graded on a 5-point scale. A total of 107 patients, 53 in the orange juice group and 54 in the polyethylene glycol-ascorbic acid group who underwent elective colonoscopy were enrolled. The palatability score (mean ± SD) was higher in the orange juice group than in the control group (2.36 ± 0.76 vs 1.78 ± 0.88; p = 0.005). Nausea was less frequent in the orange juice group (26.4% vs 59.3%; p = 0.001). Total amount of bowel preparation ingested was not significantly different between the groups (p = 0.44). The bowel preparation score (mean ± SD) was not significantly different (1.49 ± 0.80 vs 1.43 ± 0.77; p = 0.94). Willingness to repeat the same process was higher in the orange juice group (90.4% vs 66.7%; p = 0.003). This study is limited because only ambulatory patients were enrolled. Orange juice intake before drinking 2 L of polyethylene glycol-ascorbic acid for colonoscopy can reduce patient discomfort, resulting in improved acceptability and patient compliance. This method is as effective for bowel cleansing as polyethylene glycol.

  7. 21 CFR 172.820 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the total ethylene and diethylene glycol content of polyethylene glycols having mean molecular weights... and diethylene glycol content of polyethylene glycols having mean molecular weights below 450. Analytical Method ethylene glycol and diethylene glycol content of polyethylene glycols The analytical method...

  8. Polymeric compositions incorporating polyethylene glycol as a phase change material

    DOEpatents

    Salyer, Ival O.; Griffen, Charles W.

    1989-01-01

    A polymeric composition comprising a polymeric material and polyethylene glycol or end-capped polyethylene glycol as a phase change material, said polyethylene glycol and said end-capped polyethylene glycol having a molecular weight greater than about 400 and a heat of fusion greater than about 30 cal/g; the composition is useful in making molded and/or coated materials such as flooring, tiles, wall panels and the like; paints containing polyethylene glycols or end-capped polyethylene glycols are also disclosed.

  9. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Boric acid (H3BO3), mixed esters with... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

  10. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Boric acid (H3BO3), mixed esters with... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

  11. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Boric acid (H3BO3), mixed esters with... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

  12. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Boric acid (H3BO3), mixed esters with... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

  13. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Boric acid (H3BO3), mixed esters with... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

  14. Polyethylene glycol without electrolytes for children with constipation and encopresis.

    PubMed

    Loening-Baucke, Vera

    2002-04-01

    Children with functional constipation and encopresis benefit from behavior modification and from long-term laxative medication. Polyethylene glycol without electrolytes has become the first option for many pediatric gastroenterologists. Twenty-eight children treated with polyethylene glycol without electrolytes were compared with 21 children treated with milk of magnesia to evaluate the efficiency, acceptability, side effects, and treatment dosage of polyethylene glycol in long-term treatment of functional constipation and encopresis. Children were rated as "doing well," "improved," or "not doing well," depending on resolution of constipation and encopresis. At the 1-, 3-, 6-, and 12-month follow-ups, bowel movement frequency increased and soiling frequency decreased significantly in both groups. At the 1-month follow-up, children on polyethylene glycol were soiling more frequently (P < 0.01) and fewer were improved (P < 0.01). At the 3- and 6-month follow-ups, both groups had similarly improved. At the 12-month visit, 61% of children on polyethylene glycol and 67% of children on milk of magnesia were doing well. Children on polyethylene glycol soiled more frequently (P < 0.01). None refused polyethylene glycol, but 33% refused to take milk of magnesia. The mean initial treatment dosage of polyethylene glycol was 0.6 +/- 0.2 g/kg daily. Polyethylene glycol had no taste, and no loss of efficacy occurred. Polyethylene glycol did not cause clinically significant side effects. Polyethylene glycol without electrolytes is an alternative for long-term management of children with constipation and encopresis.

  15. Antiwashout behavior of calcium phosphate cement incorporated with Poly(ethylene glycol)

    NASA Astrophysics Data System (ADS)

    Hablee, S.; Sopyan, I.; Mel, M.; Salleh, H. M.; Rahman, M. M.

    2018-01-01

    The effect of powder-to-liquid ratio and addition of poly(ethylene glycol) on the antiwashout behavior of calcium phosphate cement has been investigated. Calcium hydroxide, Ca(OH)2, and diammonium hydrogen phosphate, (NH4)2HPO4, were used as precursors with distilled water as the solvent in the wet chemical precipitation synthesis of hydroxyapatite powder. Cement paste was prepared by mixing the as-synthesized powder with distilled water at certain ratios, varied at 1.0, 1.3, 1.5 and 1.6. Poly(ethylene glycol) was added into distilled water, varied at 1, 2, 3, 4 and 5 wt% using the powder-to-liquid ratio of 1.3. The antiwashout properties of the cement has been investigated by soaking in Ringer’s solution for 3 and 7 days. The evolution of compressive strength of calcium phosphate cement before and after soaking have been determined. After 7 days soaking, the strength of the cement increased by 94.4%, 2.98%, 11.39% and 111.29% for powder-to-liquid ratios 1.0, 1.3, 1.5 and 1.6 respectively. The addition of poly(ethylene glycol) up to 3% shows an increase in strength after 7 days soaking, with 57.75%, 16.4% and 19.97% increase for 1, 2 and 3% poly(ethylene glycol) contents respectively. The calcium phosphate cement produced in this current study shows excellent antiwashout behavior since no cement dissolution happened and the compressive strength of the cement increased with soaking time throughout 7 days soaking in Ringer’s solution.

  16. Degradation of ethylene glycol and polyethylene glycols by methanogenic consortia.

    PubMed Central

    Dwyer, D F; Tiedje, J M

    1983-01-01

    Methanogenic enrichments capable of degrading polyethylene glycol and ethylene glycol were obtained from sewage sludge. Ethanol, acetate, methane, and (in the case of polyethylene glycols) ethylene glycol were detected as products. The sequence of product formation suggested that the ethylene oxide unit [HO-(CH2-CH2-O-)xH] was dismutated to acetate and ethanol; ethanol was subsequently oxidized to acetate by a syntrophic association that produced methane. The rates of degradation for ethylene, diethylene, and polyethylene glycol with molecular weights of 400, 1,000, and 20,000, respectively, were inversely related to the number of ethylene oxide monomers per molecule and ranged from 0.84 to 0.13 mM ethylene oxide units degraded per h. The enrichments were shown to best metabolize glycols close to the molecular weight of the substrate on which they were enriched. The anaerobic degradation of polyethylene glycol (molecular weight, 20,000) may be important in the light of the general resistance of polyethylene glycols to aerobic degradation. PMID:6614903

  17. Cementitious building material incorporating end-capped polyethylene glycol as a phase change material

    DOEpatents

    Salyer, Ival O.; Griffen, Charles W.

    1986-01-01

    A cementitious composition comprising a cementitious material and polyethylene glycol or end-capped polyethylene glycol as a phase change material, said polyethylene glycol and said end-capped polyethylene glycol having a molecular weight greater than about 400 and a heat of fusion greater than about 30 cal/g; the compositions are useful in making pre-formed building materials such as concrete blocks, brick, dry wall and the like or in making poured structures such as walls or floor pads; the glycols can be encapsulated to reduce their tendency to retard set.

  18. Parallel determination of gut permeability in man with M(r) 400, M(r) 1500, M(r) 4000 and M(r) 10,000 polyethylene glycol.

    PubMed

    Parlesak, A; Bode, J C; Bode, C

    1994-11-01

    Polyethylene glycol has been in use for a number of years for the assessment of gut permeability. The methods so far employed are usually limited to polyethylene glycols in the low relative molecular mass range (up to M(r) 1300). We developed a method for the simultaneous determination of gut permeability to M(r) 400, M(r) 1500, M(r) 4000 and M(r) 10,000 polyethylene glycol, by applying a single oral dose of an appropriate mixture of these polyethylene glycols. After extraction from 24 h-urine, M(r) 1500, M(r) 4000 and M(r) 10,000 polyethylene glycol were quantified by size exclusion chromatography, while M(r) 400 polyethylene glycol was determined by reversed phase chromatography. The detection limit of polyethylene glycol in the relative molecular mass range between M(r) 1500 and M(r) 10,000 was found to be 0.2 mg/l urine, and the detection limit of M(r) 400 polyethylene glycol 5 mg/l urine. Recovery of the polyethylene glycols (N = 6) were 86.6% (CV: 4.8%) for M(r) 400, 94.1% (CV: 7.2%) for M(r) 1500, 97.1% (CV: 5.5%) for M(r) 4000 and 97.4% (CV: 5.6%) for M(r) 10,000. No significant difference was found between the excretion rates in 24 h-urine of M(r) 400 and M(r) 1500 polyethylene glycols in patients with Crohn's disease (M(r) 400: 34.4 +/- 5.5%; M(r) 1500: 5.22 +/- 2.27%; mean +/- SEM, N = 10) and healthy controls (M(r) 400: 33.6 +/- 3.2%, M(r) 1500: 1.09 +/- 0.26%; N = 21). The excretion rate of M(r) 4000 polyethylene glycol was markedly higher in patients with Crohn's disease (0.462 +/- 0.177%) than in healthy controls (0.049 +/- 0.012%, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

  19. A new low-volume isosmotic polyethylene glycol solution plus bisacodyl versus split-dose 4 L polyethylene glycol for bowel cleansing prior to colonoscopy: a randomised controlled trial.

    PubMed

    Cesaro, Paola; Hassan, Cesare; Spada, Cristiano; Petruzziello, Lucio; Vitale, Giovanna; Costamagna, Guido

    2013-01-01

    4-L polyethylene glycol preparations are effective for colon cleansing before colonoscopy. However, large volume and unpleasant taste reduce tolerability and acceptability limiting patient compliance. A new isosmotic low-volume polyethylene glycol preparation with citrates and simethicone plus bisacodyl has been developed to improve patient compliance and tolerability. To compare the efficacy of 2 different regimens of preparation vs a split-dose of polyethylene glycol solution. In this randomised, blinded, comparative study, 153 patients were allocated to 3 arms. Arm 1 (n=52) received bisacodyl and 2-L polyethylene glycol with citrates and simethicone the day before the procedure. Arm 2 (n=50) received bisacodyl the day before and 2-L polyethylene glycol with citrates and simethicone on the day of colonoscopy. Control group (n=51) received a split-dose of 4-L polyethylene glycol. Cleansing was evaluated according to Ottawa scale. The mean Ottawa score was not different in the 3 groups. Excellent cleansing was observed more frequently in arm 2 (70%) than in controls (49%) (p<0.05). No serious adverse events were observed in the 3 regimens. The willingness to repeat the same bowel preparation was superior in arms 1 and 2 than in controls (p<0.001). New low-volume preparations seem to be as effective as the split 4-L polyethylene glycol regimen, showing a better tolerability and acceptability. Copyright © 2012. Published by Elsevier Ltd.

  20. Multidimensional chromatographic techniques for hydrophilic copolymers II. Analysis of poly(ethylene glycol)-poly(vinyl acetate) graft copolymers.

    PubMed

    Knecht, Daniela; Rittig, Frank; Lange, Ronald F M; Pasch, Harald

    2006-10-13

    A large variety of hydrophilic copolymers is applied in different fields of chemical industry including bio, pharma and pharmaceutical applications. For example, poly(ethylene glycol)-poly(vinyl alcohol) graft copolymers that are used as tablet coatings are responsible for the controlled release of the active compounds. These copolymers are produced by grafting of vinyl acetate onto polyethylene glycol (PEG) and subsequent hydrolysis of the poly(ethylene glycol)-poly(vinyl acetate) graft copolymers. The poly(ethylene glycol)-poly(vinyl acetate) copolymers are distributed with regard to molar mass and chemical composition. In addition, they frequently contain the homopolymers polyethylene glycol and polyvinyl acetate. The comprehensive analysis of such complex systems requires hyphenated analytical techniques, including two-dimensional liquid chromatography and combined LC and nuclear magnetic resonance spectroscopy. The development and application of these techniques are discussed in the present paper.

  1. Photocurable poly(ethylene glycol) as a bioink for the inkjet 3D pharming of hydrophobic drugs.

    PubMed

    Acosta-Vélez, Giovanny F; Zhu, Timothy Z; Linsley, Chase S; Wu, Benjamin M

    2018-04-26

    Binder jetting and material extrusion are the two most common additive manufacturing techniques used to create pharmaceutical tablets. However, their versatility is limited since the powder component is present throughout the dosage forms fabricated by binder jet 3D printing and material extrusion 3D printing requires high operating temperatures. Conversely, material jetting allows for compositional control at a voxel level and can dispense material at room temperature. Unfortunately, there are a limited number of materials that are both printable and biocompatible. Therefore, the aim of this study was to engineer photocurable bioinks that are suitable for hydrophobic active pharmaceutical ingredients and have rapid gelation times upon visible light exposure. The resulting bioinks were comprised of poly(ethylene glycol) diacrylate (250 Da) as the crosslinkable monomer, Eosin Y as the photoinitiator, and methoxide-poly(ethylene glycol)-amine as the coinitiator. Additionally, poly(ethylene glycol) (200 Da) was added as a plasticizer to modulate the drug release profiles, and Naproxen was used as the model drug due to its high hydrophobicity. Various bioink formulations were dispensed into the bottom half of blank preform tablets - made via direct compression - using a piezoelectric nozzle, photopolymerized, and capped with the top half of the preform tablet to complete the pharmaceutical dosage form. Results from the release studies showed that drug release can be modulated by both the percent of poly(ethylene glycol) diacrylate in the formulation and the light exposure time used to cure the bioinks. These bioinks have the potential to expand the library of materials available for creating pharmaceutical tablets via inkjet printing with personalized drug dosages. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. The effect of glycerol, propylene glycol and polyethylene glycol 400 on the partition coefficient of benzophenone-3 (oxybenzone).

    PubMed

    Mbah, C J

    2007-01-01

    Sunscreen products are widely used to protect the skin from sun-related deleterious effects. The objective of the study was to investigate the potential effect of glycerol, propylene glycol and polyethylene glycol 400 on dermal absorption of oxybenzone by studying their effects on its partition coefficient. The partition coefficient was evaluated in a chloroform-water system at room temperature. It was found that glycerol and propylene glycol decreased the partition coefficient of oxybenzone, while an increase in partition coefficient was observed with polyethylene glycol 400. The findings suggest that polyethylene glycol 400 in contrast to glycerol and propylene glycol has the potential of increasing the vehicle-skin partition coefficient of oxybenzone when cosmetic products containing such an UV absorber are topically applied to the skin.

  3. Inverse Gas Chromatography

    DTIC Science & Technology

    1990-09-01

    propellants in a number of Defense systems (1-3). These include: polyneopentyl glycol azelate (NPGA) in HAWK; hydroxy-terminated polybutadiene (HTPB) in VIPER...PATRIOT, MET ROCKET, GSRS, PERSHING, and HELLFIRE; polybutadiene acrylic acid (PBAA) in PERSHING and SPARTAN; and polyethylene glycol (PEG...mixtures of this with polybutadiene acrylic acid ; polyethylene glycol + polyethylene glycol adipate; etc.). Furthermore, yet to be explored in any detail

  4. Membranes of Polymers of Intrinsic Microporosity (PIM-1) Modified by Poly(ethylene glycol).

    PubMed

    Bengtson, Gisela; Neumann, Silvio; Filiz, Volkan

    2017-06-05

    Until now, the leading polymer of intrinsic microporosity PIM-1 has become quite famous for its high membrane permeability for many gases in gas separation, linked, however, to a rather moderate selectivity. The combination with the hydrophilic and low permeable poly(ethylene glycol) (PEG) and poly(ethylene oxides) (PEO) should on the one hand reduce permeability, while on the other hand enhance selectivity, especially for the polar gas CO₂ by improving the hydrophilicity of the membranes. Four different paths to combine PIM-1 with PEG or poly(ethylene oxide) and poly(propylene oxide) (PPO) were studied: physically blending, quenching of polycondensation, synthesis of multiblock copolymers and synthesis of copolymers with PEO/PPO side chain. Blends and new, chemically linked polymers were successfully formed into free standing dense membranes and measured in single gas permeation of N₂, O₂, CO₂ and CH₄ by time lag method. As expected, permeability was lowered by any substantial addition of PEG/PEO/PPO regardless the manufacturing process and proportionally to the added amount. About 6 to 7 wt % of PEG/PEO/PPO added to PIM-1 halved permeability compared to PIM-1 membrane prepared under similar conditions. Consequently, selectivity from single gas measurements increased up to values of about 30 for CO₂/N₂ gas pair, a maximum of 18 for CO₂/CH₄ and 3.5 for O₂/N₂.

  5. 40 CFR 721.10518 - Diethylene glycol, polymer with diisocyanatoalkane, polyethylene glycol monomethyl ether- and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Diethylene glycol, polymer with... Substances § 721.10518 Diethylene glycol, polymer with diisocyanatoalkane, polyethylene glycol monomethyl... subject to reporting. (1) The chemical substance identified generically as diethylene glycol, polymer with...

  6. 40 CFR 721.10546 - Pentenylated polyethylene glycol sulfate salt (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... sulfate salt (generic). 721.10546 Section 721.10546 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10546 Pentenylated polyethylene glycol sulfate salt... identified generically as pentenylated polyethylene glycol sulfate salt (PMN P-04-340) is subject to...

  7. 40 CFR 721.10546 - Pentenylated polyethylene glycol sulfate salt (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... sulfate salt (generic). 721.10546 Section 721.10546 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10546 Pentenylated polyethylene glycol sulfate salt... identified generically as pentenylated polyethylene glycol sulfate salt (PMN P-04-340) is subject to...

  8. 40 CFR 721.3900 - Alkyl polyethylene glycol phosphate, potassium salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., potassium salt. 721.3900 Section 721.3900 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.3900 Alkyl polyethylene glycol phosphate, potassium salt. (a) Chemical... as alkyl polyethylene glycol phosphate, potassium salt (P-90-481), is subject to reporting under this...

  9. 40 CFR 721.3900 - Alkyl polyethylene glycol phosphate, potassium salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., potassium salt. 721.3900 Section 721.3900 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.3900 Alkyl polyethylene glycol phosphate, potassium salt. (a) Chemical... as alkyl polyethylene glycol phosphate, potassium salt (P-90-481), is subject to reporting under this...

  10. 40 CFR 721.3900 - Alkyl polyethylene glycol phosphate, potassium salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., potassium salt. 721.3900 Section 721.3900 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.3900 Alkyl polyethylene glycol phosphate, potassium salt. (a) Chemical... as alkyl polyethylene glycol phosphate, potassium salt (P-90-481), is subject to reporting under this...

  11. 40 CFR 721.3900 - Alkyl polyethylene glycol phosphate, potassium salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., potassium salt. 721.3900 Section 721.3900 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.3900 Alkyl polyethylene glycol phosphate, potassium salt. (a) Chemical... as alkyl polyethylene glycol phosphate, potassium salt (P-90-481), is subject to reporting under this...

  12. 21 CFR 573.800 - Polyethylene glycol (400) mono- and dioleate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.800 Polyethylene glycol (400) mono- and dioleate. (a) The food additive polyethylene glycol (400) mono- and dioleate meets the following specifications...

  13. 21 CFR 573.800 - Polyethylene glycol (400) mono- and dioleate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.800 Polyethylene glycol (400) mono- and dioleate. (a) The food additive polyethylene glycol (400) mono- and dioleate meets the following specifications...

  14. 21 CFR 573.800 - Polyethylene glycol (400) mono- and dioleate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.800 Polyethylene glycol (400) mono- and dioleate. (a) The food additive polyethylene glycol (400) mono- and dioleate meets the following specifications...

  15. 21 CFR 573.800 - Polyethylene glycol (400) mono- and dioleate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.800 Polyethylene glycol (400) mono- and dioleate. (a) The food additive polyethylene glycol (400) mono- and dioleate meets the following specifications...

  16. 21 CFR 573.800 - Polyethylene glycol (400) mono- and dioleate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.800 Polyethylene glycol (400) mono- and dioleate. (a) The food additive polyethylene glycol (400) mono- and dioleate meets the following specifications...

  17. 40 CFR 721.10472 - 1,3-Benzenedimethanamine, polymers with epichlorohydrin-polyethylene glycol reaction products.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 1,3-Benzenedimethanamine, polymers...-Benzenedimethanamine, polymers with epichlorohydrin-polyethylene glycol reaction products. (a) Chemical substance and..., polymers with epichlorohydrin-polyethylene glycol reaction products (PMN P-03-645; CAS No. 652968-34-8) is...

  18. 40 CFR 721.10472 - 1,3-Benzenedimethanamine, polymers with epichlorohydrin-polyethylene glycol reaction products.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 1,3-Benzenedimethanamine, polymers...-Benzenedimethanamine, polymers with epichlorohydrin-polyethylene glycol reaction products. (a) Chemical substance and..., polymers with epichlorohydrin-polyethylene glycol reaction products (PMN P-03-645; CAS No. 652968-34-8) is...

  19. Adenovirus vector covalently conjugated to polyethylene glycol with a cancer-specific promoter suppresses the tumor growth through systemic administration.

    PubMed

    Yao, Xinglei; Yoshioka, Yasuo; Morishige, Tomohiro; Eto, Yusuke; Narimatsu, Shogo; Mizuguchi, Hiroyuki; Mukai, Yohei; Okada, Naoki; Nakagawa, Shinsaku

    2010-01-01

    Cancer gene therapy with adenovirus vectors (Adv) is limited to local administration because systemic administration of Adv produces a weak therapeutic effect and severe side effects. Previously, we generated a dual cancer-specific Adv system by using Adv covalently conjugated to polyethylene glycol (PEG) for transductional targeting and the telomere reverse transcriptase (TERT) promoter as a cancer-specific promoter for transcriptional targeting (PEG-Ad-TERT). We demonstrated that systemic administration of PEG-Ad-TERT showed superior antitumor effects against lung metastatic cancer with negligible side effects. Here, we investigated the therapeutic efficacy of systemic administration of PEG-Ad-TERT for the treatment of primary tumors. We first evaluated the transgene expression of PEG-Ad-TERT containing the luciferase gene (PEG-Ad-TERT/Luc) in primary tumors. Systemic administration of PEG-Ad-TERT/Luc resulted high transgene expression, similar to that observed in tumors for the conventional cytomegalovirus (CMV) promoter-driven Adv containing the luciferase gene (Ad-CMV/Luc). By comparison, transgene expression was 2500-fold lower than that of Ad-CMV/Luc in liver. We then examined the therapeutic effect of systemic administration of PEG-Ad-TERT containing the herpes simplex virus thymidine kinase (HSVtk) gene (PEG-Ad-TERT/HSVtk) for the treatment of primary tumors. We showed that PEG-Ad-TERT/HSVtk produced a notable antitumor effect against primary tumors with negligible side effects. These results demonstrated that PEG-Ad-TERT can be regarded as a prototype Adv with suitable efficacy and safety for systemic cancer gene therapy against both metastatic and primary tumors.

  20. An evaluation of the effects of PEO/PEG molecular weights on extruded alumina rods

    NASA Astrophysics Data System (ADS)

    Bolger, Nancy Beth

    1998-12-01

    Alumina rods were piston extruded from bodies containing polyethylene glycols (PEGs) and polyethylene oxides (PEOs) with molecular weights ranging from 1,300 to 3,800,000 g/mol. A blend of aluminas possessing different particle size distributions was evaluated with regard to its extrusion pressure by varying the amount of PEG/PEO addition. Behavior exhibited by the alumina blend was dependent upon the additive that was used. The higher molecular weight binders with average molecular weight of 200,000 g/mol and 3,350,000 g/mol displayed the most severe behaviors of near dilatant and dilatant respectively. Physical properties of the green and fired states, as well as the binder burnout, were investigated with the changing additions. Correlation between the green and fired strengths and the changing molecular weights were examined. The additive present influenced the surface properties of the rods, which affected the green strengths. The highest average molecular weight polyethylene glycols showed higher green strengths, while the lowest green strengths were observed for the high molecular weight polyethylene oxides. Fired strengths generally ranged from approximately 12,000 psi to 16,000 psi for additive batches. Alumina pellets containing twelve separate combinations of polyethylene glycol with polyethylene oxide were dry pressed. Physical properties of the green and fired states were examined. Statistical analysis was performed upon the data and seven combinations of polyethylene glycol with polyethylene oxide were deemed significant. These combinations in conjunction with the same alumina blend were then piston extruded. The addition of polyethylene glycol reduced the near dilatant behavior exhibited by the 200,000 g/mol average molecular weight polyethylene oxide. Dilatant behavior was completely eliminated from the 3,350,000 g/mol average molecular weight polyethylene oxide batches. Physical properties of the green and fired states were again investigated with the changing additions. Polyethylene oxide, in combination with polyethylene glycol, did show an increase in green strength versus the polyethylene oxide alone. Strengths were still lower than those displayed by the polyethylene glycols alone. Reductions or degradations in molecular weight of the polymers due to mixing and extrusion processes may account for lower green strength of bodies, especially those containing polyethylene oxides.

  1. Effects of adding protein, condensed tannins, and polyethylene glycol to diets of sheep and goats fed one-seed juniper and low quality roughage

    USDA-ARS?s Scientific Manuscript database

    The biochemical mechanisms that limit voluntary intake of one-seed juniper by browsing ruminants are not well understood. Twelve Rambouillet ewes (78 ± 2.3 kg BW) and 12 Boer-Spanish does (54 ± 1.4 kg BW) were used in a split-plot sequence design to investigate the effects of adding protein, quebrac...

  2. Synthesis of Cu{sub 2}ZnSnS{sub 4} nanoparticles and controlling the morphology with polyethylene glycol

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rawat, Kusum; Department of Electronic Science, University of Delhi South Campus, Delhi 110021; Kim, Hee-Joon

    Highlights: • Cu{sub 2}ZnSnS{sub 4} nanoparticles were synthesized by wet chemical technique. • First report on the effect of using polyethylene glycol as a structure directing agent on Cu{sub 2}ZnSnS{sub 4} nanoparticles. • The morphology of Cu{sub 2}ZnSnS{sub 4} nanoparticles changes into nanoflakes and nanorods structures with polyethylene glycol concentration. • Polyethylene glycol assisted Cu{sub 2}ZnSnS{sub 4} nanoparticle film exhibits optical bandgap of 1.5 eV which is suitable for the application in solar cells. - Abstract: Cu{sub 2}ZnSnS{sub 4} nanoparticles were synthesized by wet chemical technique using metal thiourea precursor at 250 °C. The structural and morphological properties of asmore » grown nanoparticles have been characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. The influence of different concentration of polyethylene glycol as structure directing agent on the morphologies of Cu{sub 2}ZnSnS{sub 4} nanoparticles are investigated on thin films deposited by spin coating technique. The mean crystallite size of the Cu{sub 2}ZnSnS{sub 4} nanoparticles was found to improve with polyethylene glycol concentration. Scanning electron microscopy images of Cu{sub 2}ZnSnS{sub 4} revealed aggregated spherical shaped nanoparticles whereas the polyethylene glycol assisted Cu{sub 2}ZnSnS{sub 4} nanoparticle films show nanoflakes and nanorods structures with increasing concentration of polyethylene glycol. Transmission electron microscopy analysis has also been performed to determine the size and structure of nanorods. UV–vis absorption spectroscopy shows the broad band absorption with optical bandgap of 1.50 eV for polyethylene glycol assisted Cu{sub 2}ZnSnS{sub 4} films.« less

  3. 78 FR 78748 - 2,5-Furandione, polymer With ethenylbenzene, Reaction Products With polyethylene-polypropylene...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ..., polymer With ethenylbenzene, Reaction Products With polyethylene-polypropylene glycol 2-aminopropyl Me...-furandione, polymer with ethenylbenzene, reaction products with polyethylene-polypropylene glycol 2... residues of 2,5-furandione, polymer with ethenylbenzene, reaction products with polyethylene-polypropylene...

  4. 21 CFR 178.3750 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... are not applicable to polyethylene glycols used in food-packaging adhesives complying with § 175.105... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Polyethylene glycol (mean molecular weight 200-9,500). 178.3750 Section 178.3750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  5. 21 CFR 178.3750 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... are not applicable to polyethylene glycols used in food-packaging adhesives complying with § 175.105... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Polyethylene glycol (mean molecular weight 200-9,500). 178.3750 Section 178.3750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  6. 21 CFR 178.3750 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... are not applicable to polyethylene glycols used in food-packaging adhesives complying with § 175.105... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Polyethylene glycol (mean molecular weight 200-9,500). 178.3750 Section 178.3750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  7. Curcumin Encapsulated into Methoxy Poly(Ethylene Glycol) Poly(ε-Caprolactone) Nanoparticles Increases Cellular Uptake and Neuroprotective Effect in Glioma Cells.

    PubMed

    Marslin, Gregory; Sarmento, Bruno Filipe Carmelino Cardoso; Franklin, Gregory; Martins, José Alberto Ribeiro; Silva, Carlos Jorge Ribeiro; Gomes, Andreia Ferreira Castro; Sárria, Marisa Passos; Coutinho, Olga Maria Fernandes Pereira; Dias, Alberto Carlos Pires

    2017-03-01

    Curcumin is a natural polyphenolic compound isolated from turmeric ( Curcuma longa ) with well-demonstrated neuroprotective and anticancer activities. Although curcumin is safe even at high doses in humans, it exhibits poor bioavailability, mainly due to poor absorption, fast metabolism, and rapid systemic elimination. To overcome these issues, several approaches, such as nanoparticle-mediated targeted delivery, have been undertaken with different degrees of success. The present study was conducted to compare the neuroprotective effect of curcumin encapsulated in poly( ε -caprolactone) and methoxy poly(ethylene glycol) poly( ε -caprolactone) nanoparticles in U251 glioblastoma cells. Prepared nanoparticles were physically characterized by laser doppler anemometry, transmission electron microscopy, and X-ray diffraction. The results from laser doppler anemometry confirmed that the size of poly( ε -caprolactone) and poly(ethylene glycol) poly( ε -caprolactone) nanoparticles ranged between 200-240 nm for poly( ε -caprolactone) nanoparticles and 30-70 nm for poly(ethylene glycol) poly( ε -caprolactone) nanoparticles, and transmission electron microscopy images revealed their spherical shape. Treatment of U251 glioma cells and zebrafish embryos with poly( ε -caprolactone) and poly(ethylene glycol) poly( ε -caprolactone) nanoparticles loaded with curcumin revealed efficient cellular uptake. The cellular uptake of poly(ethylene glycol) poly( ε -caprolactone) nanoparticles was higher in comparison to poly( ε -caprolactone) nanoparticles. Moreover, poly(ethylene glycol) poly( ε -caprolactone) di-block copolymer-loaded curcumin nanoparticles were able to protect the glioma cells against tBHP induced-oxidative damage better than free curcumin. Together, our results show that curcumin-loaded poly(ethylene glycol) poly( ε -caprolactone) di-block copolymer nanoparticles possess significantly stronger neuroprotective effect in U251 human glioma cells compared to free curcumin and curcumin-loaded poly( ε -caprolactone) nanoparticles. Georg Thieme Verlag KG Stuttgart · New York.

  8. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Riande, E.; Guzman, J.; Roman, J.S.

    The dipole moments of poly (thiodiethylene glycol terephthalate) chains were determined as a function of temperature by means of dielectric constant measurements in dioxane. The experimental results were found to be in fair agreement with theoretical results based on a rotational isomeric state model in which the required conformational energies were obtained from previous configurational analysis on poly(ethylene terephthalate), poly(diethylene glycol terephthalate) and poly(thiodiethylene glycol). Since poly(thiodiethylene glycol terephthalate) can be considered an alternating copolymer of ethylene terephthalate and thioethylene units, its configuration-dependent properties were compared with those of poly(ethylene terephthalate) and poly(ethylene sulfide). It was found the flexibility ofmore » the copolymer, as expressed by the partition function, intermediate to that of its parent homopolymers. The theoretical results also indicate that the dimensions of poly(thiodiethylene glycol) are similar to those of poly(ethylene terephthalate) while its dipole moment ratio resembles that of poly(ethylene sulfide).« less

  9. Highly conductive solid polymer electrolyte membranes based on polyethylene glycol-bis-carbamate dimethacrylate networks

    NASA Astrophysics Data System (ADS)

    Fu, Guopeng; Dempsey, Janel; Izaki, Kosuke; Adachi, Kaoru; Tsukahara, Yasuhisa; Kyu, Thein

    2017-08-01

    In an effort to fabricate highly conductive, stable solid-state polymer electrolyte membranes (PEM), polyethylene glycol bis-carbamate (PEGBC) was synthesized via condensation reaction between polyethylene glycol diamine and ethylene carbonate. Subsequently, dimethacrylate groups were chemically attached to both ends of PEGBC to afford polyethylene glycol-bis-carbamate dimethacrylate (PEGBCDMA) precursor having crosslinking capability. The melt-mixed ternary mixtures consisting of PEGBCDMA, succinonitrile plasticizer, and lithium trifluorosulphonyl imide salt were completely miscible in a wide compositional range. Upon photo-crosslinking, the neat PEGBCDMA network was completely amorphous exhibiting higher tensile strength, modulus, and extensibility relative to polyethylene glycol diacrylate (PEGDA) counterpart. Likewise, the succinonitrile-plasticized PEM network containing PEGBCDMA remained completely amorphous and transparent upon photo-crosslinking, showing superionic conductivity, improved thermal stability, and superior tensile properties with improved capacity retention during charge/discharge cycling as compared to the PEGDA-based PEM.

  10. A novel folate-modified self-microemulsifying drug delivery system of curcumin for colon targeting.

    PubMed

    Zhang, Lin; Zhu, Weiwei; Yang, Chunfen; Guo, Hongxia; Yu, Aihua; Ji, Jianbo; Gao, Yan; Sun, Min; Zhai, Guangxi

    2012-01-01

    The objective of this study was to prepare, characterize, and evaluate a folate-modified self-microemulsifying drug delivery system (FSMEDDS) with the aim to improve the solubility of curcumin and its delivery to the colon, facilitating endocytosis of FSMEDDS mediated by folate receptors on colon cancer cells. Ternary phase diagrams were constructed in order to obtain the most efficient self-emulsification region, and the formulation of curcumin-loaded SMEDDS was optimized by a simplex lattice experiment design. Then, three lipophilic folate derivatives (folate-polyethylene glycol-distearoylphosphatidylethanolamine, folate-polyethylene glycol-cholesteryl hemisuccinate, and folate-polyethylene glycol-cholesterol) used as a surfactant were added to curcumin-loaded SMEDDS formulations. An in situ colon perfusion method in rats was used to optimize the formulation of FSMEDDS. Curcumin-loaded FSMEDDS was then filled into colon-targeted capsules and the in vitro release was investigated. Cytotoxicity studies and cellular uptake studies was used in this research. The optimal formulation of FSMEDDS obtained with the established in situ colon perfusion method in rats was comprised of 57.5% Cremophor(®) EL, 32.5% Transcutol(®) HP, 10% Capryol™ 90, and a small amount of folate-polyethylene glycol-cholesteryl hemisuccinate (the weight ratio of folate materials to Cremophor EL was 1:100). The in vitro release results indicated that the obtained formulation of curcumin could reach the colon efficiently and release the drug immediately. Cellular uptake studies analyzed with fluorescence microscopy and flow cytometry indicated that the FSMEDDS formulation could efficiently bind with the folate receptors on the surface of positive folate receptors cell lines. In addition, FSMEDDS showed greater cytotoxicity than SMEDDS in the above two cells. FSMEDDS-filled colon-targeted capsules are a potential carrier for colon delivery of curcumin.

  11. Polyethylene Glycol-Poly(2-Methyl-5-Vinyl Tetrazole) Polymer Blend (A desensitizing Binder for Propellants and Explosives)

    DTIC Science & Technology

    1989-03-01

    PVA, CTBN , PBAA, PMMA, etc. As a test of this predictability, we dissolved a vinyl acetate polymer in THF, and then added PMVT, and did succeed in...Polyvinyl acetate CTBN Carboxy terminated butadiene acrylonitrile PBAA Polybutadiene acrylic acid PMMA Polymethyl. methacrylate THF Tetrahydrofuran NMR

  12. PEG and Thickeners: A Critical Interaction Between Polyethylene Glycol Laxative and Starch-Based Thickeners.

    PubMed

    Carlisle, Brian J; Craft, Garrett; Harmon, Julie P; Ilkevitch, Alina; Nicoghosian, Jenik; Sheyner, Inna; Stewart, Jonathan T

    2016-09-01

    Clinicians commonly encounter dysphagia and constipation in a skilled nursing population. Increasing the viscosity of liquids, usually with a starch- or xanthan gum-based thickener, serves as a key intervention for patients with dysphagia. We report a newly identified and potentially dangerous interaction between polyethylene glycol 3350 laxative (PEG) and starch-thickened liquids. A patient requiring nectar-thickened liquids became constipated, and medical staff prescribed PEG for constipation. His nurse observed that the thickened apple juice immediately thinned to near-water consistency when PEG was added. She obtained the same results with thickened water and coffee. We quantified this phenomenon by isothermal rotational rheology. Results confirmed a precipitous loss of thickening when PEG was added to starch-based thickeners but not with xanthan gum-based thickeners. Clinicians and front-line staff should be aware of this potentially critical interaction between PEG- and starch-based thickeners. Although confirmatory studies are needed, our preliminary data suggest that PEG may be compatible with xanthan gum-- based thickeners. Copyright © 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine. All rights reserved.

  13. Highly efficient SO₂ absorption and its subsequent utilization by weak base/polyethylene glycol binary system.

    PubMed

    Yang, Zhen-Zhen; He, Liang-Nian; Zhao, Ya-Nan; Yu, Bing

    2013-02-05

    A binary system consisting of polyethylene glycol (PEG, proton donor)/PEG-functionalized base with suitable basicity was developed for efficient gas desulfurization (GDS) and can be regarded as an alternative approach to circumvent the energy penalty problem in the GDS process. High capacity for SO(2) capture up to 4.88 mol of SO(2)/mol of base was achieved even under low partial pressure of SO(2). Furthermore, SO(2) desorption runs smoothly under mild conditions (N(2), 25 °C) and no significant drop in SO(2) absorption was observed after five-successive absorption-desorption cycles. On the other hand, the absorbed SO(2) by PEG(150)MeIm/PEG(150), being considered as the activated form of SO(2), can be directly transformed into value-added chemicals under mild conditions, thus eliminating the energy penalty for SO(2) desorption and simultaneously realizing recycle of the absorbents. Thus, this SO(2) capture and utilization (SCU) process offers an alternative way for GDS and potentially enables the SO(2) conversion from flue gas to useful chemicals as a value-added process.

  14. Studies of Plasticized-Polymer Electrolytes Containing Mixed Zn(II) and Li(I)

    DTIC Science & Technology

    1992-06-12

    iIIIII1iIIII!I 14. SUBJECT TERMS 15. tdUMnnrri . 9 poly(ethylene glycol) ( PEG ), poly(ethylene glycol dimethyl ether) (PEGDME), 16. PRICE CODE...glycol) ( PEG ) and poly(ethylene glycol dimethyl ether) (PEGDME). The addition of salts to either PEO or plasticized-PEO strongly influences the...were found to depend on salt concentration. Td varied from 385 to 3350 C as the zinc content was increased from 0 to 100%. Thus the overall thermal

  15. 40 CFR 721.10505 - Phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol mono-C12...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phosphoric acid, mixed mono- and... Phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol mono-C12-16-alkyl... identified as phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol mono...

  16. 40 CFR 721.10505 - Phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol mono-C12...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phosphoric acid, mixed mono- and... Phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol mono-C12-16-alkyl... identified as phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol mono...

  17. 21 CFR 172.820 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ethylene oxide and water with a mean molecular weight of 200 to 9,500. (2) It contains no more than 0.2 percent total by weight of ethylene and diethylene glycols when tested by the analytical methods... the total ethylene and diethylene glycol content of polyethylene glycols having mean molecular weights...

  18. [Comparative Study on Bowel Preparation Efficacy of Ascorbic Acid Containing Polyethylene Glycol by Adding Either Simethicone or 1 L of Water in Health Medical Examination Patients: A Prospective Randomized Controlled Study].

    PubMed

    Yeo, Se Hwan; Kwak, Jae Hoon; Kim, Yeo Un; Kwon, Tae Ho; Park, Jeong Bae; Park, Jun Hyung; Lee, Yong Kook; Lim, Yun Jeong; Yang, Chang Heon

    2016-04-25

    There are no studies that looked into the bubble eliminating efficacy of polyethylene glycol with ascorbic acid (PEGA), which has been one of the shortcomings of polyethylene glycol (PEG). In this study, we compared newly introduced PEGA regimen by adding either simethicone or 1 L of water. A prospective randomized controlled study was carried out at Dongguk Universtiy Gyeongju Hospital from July 2014 to September 2014. A total of 90 patients were randomly assigned to 3 groups; PEGA group (n=30) which served as control, simethicone addition group (n=30) to which simethicone 400 mg was additionally prescribed, and water addition group (n=30) to whom additional 1 L of water was given. Cleansing effectiveness, gas elimination efficacy, side effects, and patient satisfaction were compared between the groups. PEGA group demonstrated the highest cleansing effectiveness, but there was no statistically significant difference among the groups. Simethicone addition group showed significantly lesser amount of bubbles than the other groups (2.57±2.05 vs. 1.10±1.83 vs. 2.60±2.84, p=0.017). The rates of side effects in each group were 20.00% vs. 16.77% vs. 53.33%. Water addition group had significantly more side effects than the PEGA group and the simethicone addition group (p=0.003). The patient satisfaction score of each group was 3.37±0.85 vs. 3.73±0.74 vs. 3.20±0.66 with simethicone addition group showing significantly higher satisfaction than water addition group (p=0.020). PEGA bowel preparation agent showed satisfactory bowel cleansing despite the decrease in dosage, and addition of simethicone resulted in better bubble elimination.

  19. 21 CFR 349.12 - Ophthalmic demulcents.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Polyethylene glycol 300, 0.2 to 1 percent. (3) Polyethylene glycol 400, 0.2 to 1 percent. (4) Polysorbate 80, 0.2 to 1 percent. (5) Propylene glycol, 0.2 to 1 percent. (e) Polyvinyl alcohol, 0.1 to 4 percent. (f...

  20. 21 CFR 349.12 - Ophthalmic demulcents.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Polyethylene glycol 300, 0.2 to 1 percent. (3) Polyethylene glycol 400, 0.2 to 1 percent. (4) Polysorbate 80, 0.2 to 1 percent. (5) Propylene glycol, 0.2 to 1 percent. (e) Polyvinyl alcohol, 0.1 to 4 percent. (f...

  1. 21 CFR 349.12 - Ophthalmic demulcents.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Polyethylene glycol 300, 0.2 to 1 percent. (3) Polyethylene glycol 400, 0.2 to 1 percent. (4) Polysorbate 80, 0.2 to 1 percent. (5) Propylene glycol, 0.2 to 1 percent. (e) Polyvinyl alcohol, 0.1 to 4 percent. (f...

  2. Preparative crystallization of a single chain antibody using an aqueous two-phase system.

    PubMed

    Huettmann, Hauke; Berkemeyer, Matthias; Buchinger, Wolfgang; Jungbauer, Alois

    2014-11-01

    A simultaneous crystallization and aqueous two-phase extraction of a single chain antibody was developed, demonstrating process integration. The process conditions were designed to form an aqueous two-phase system, and to favor crystallization, using sodium sulfate and PEG-2000. At sufficiently high concentrations of PEG, a second phase was generated in which the protein crystallization occurred simultaneously. The single chain antibody crystals were partitioned to the top, polyethylene glycol-rich phase. The crystal nucleation took place in the sodium sulfate-rich phase and at the phase boundary, whereas crystal growth was progressing mainly in the polyethylene glycol-rich phase. The crystals in the polyethylene glycol-rich phase grew to a size of >50 µm. Additionally, polyethylene glycol acted as an anti-solvent, thus, it influenced the crystallization yield. A phase diagram with an undersaturation zone, crystallization area, and amorphous precipitation zone was established. Only small differences in polyethylene glycol concentration caused significant shifts of the crystallization yield. An increase of the polyethylene glycol content from 2% (w/v) to 4% (w/v) increased the yield from approximately 63-87%, respectively. Our results show that crystallization in aqueous two-phase systems is an opportunity to foster process integration. © 2014 Wiley Periodicals, Inc.

  3. Comparative toxicity of pristine graphene oxide and its carboxyl, imidazole or polyethylene glycol functionalized products to Daphnia magna: A two generation study.

    PubMed

    Liu, Yingying; Han, Wenli; Xu, Zhizhen; Fan, Wenhong; Peng, Weihua; Luo, Shenglian

    2018-06-01

    To investigate the chronic toxicity of graphene oxide (GO) and its functionalized products (GO-carboxyl, GO-imidazole and GO-polyethylene glycol), a two-generation study was conducted using the aquatic model species Daphnia magna. Each generation of daphnids were exposed for 21 days to 1.0 mg L -1 graphene material, with body length, neonate number, time of first brood and the intrinsic rate of natural increase (r) assessed as endpoints. Chronic exposure to GO, GO-carboxyl, and GO-imidazole had no adverse effect on body length or offspring number in the daphnid F0 generation, however, this exposure paradigm led to significant growth or reproduction inhibition in the following generation. Meanwhile, GO was found to show the strongest inhibitory effect, sequentially followed by GO-carboxyl and GO-imidazole. With exposure to GO-polyethylene glycol, no significant effects on growth or reproduction were observed for both F0 and F1 generation daphnids. These results reveal that carboxyl, imidazole and polyethylene glycol functional attachments alleviate the bio-toxicity of GO, especially polyethylene glycol. The increased C/O atomic ratio present in GO-carboxyl, GO-imidazole and GO-polyethylene glycol due to functionalization may mainly explain the reduced toxicity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Solubility of lysozyme in polyethylene glycol-electrolyte mixtures: the depletion interaction and ion-specific effects.

    PubMed

    Boncina, Matjaz; Rescic, Jurij; Vlachy, Vojko

    2008-08-01

    The solubility of aqueous solutions of lysozyme in the presence of polyethylene glycol and various alkaline salts was studied experimentally. The protein-electrolyte mixture was titrated with polyethylene glycol, and when precipitation of the protein occurred, a strong increase of the absorbance at 340 nm was observed. The solubility data were obtained as a function of experimental variables such as protein and electrolyte concentrations, electrolyte type, degree of polymerization of polyethylene glycol, and pH of the solution; the last defines the net charge of the lysozyme. The results indicate that the solubility of lysozyme decreases with the addition of polyethylene glycol; the solubility is lower for a polyethylene glycol with a higher degree of polymerization. Further, the logarithm of the protein solubility is a linear function of the polyethylene glycol concentration. The process is reversible and the protein remains in its native form. An increase of the electrolyte (NaCl) concentration decreases the solubility of lysozyme in the presence and absence of polyethylene glycol. The effect can be explained by the screening of the charged amino residues of the protein. The solubility experiments were performed at two different pH values (pH = 4.0 and 6.0), where the lysozyme net charge was +11 and +8, respectively. Ion-specific effects were systematically investigated. Anions such as Br(-), Cl(-), F(-), and H(2)PO(4)(-) (all in combination with Na(+)), when acting as counterions to a protein with positive net charge, exhibit a strong effect on the lysozyme solubility. The differences in protein solubility for chloride solutions with different cations Cs(+), K(+), and Na(+) (coions) were much smaller. The results at pH = 4.0 show that anions decrease the lysozyme solubility in the order F(-) < H(2)PO(4)(-) < Cl(-) < Br(-) (the inverse Hofmeister series), whereas cations follow the direct Hofmeister series (Cs(+) < K(+) < Na(+)) in this situation.

  5. Coherent source interaction, third-order nonlinear response of synthesized PEG coated magnetite nanoparticles in polyethylene glycol and its application

    NASA Astrophysics Data System (ADS)

    Gopal, S. Veena; Chitrambalam, S.; Joe, I. Hubert

    2018-01-01

    Third-order nonlinear response of synthesized polyethylene glycol coated Fe3O4 nanoparticles dispersed in a suitable solvent, polyethylene glycol has been studied. The structural characterization of the synthesized magnetite nanoparticles were carried out. The linear optical property of the synthesized magnetite nanoparticles was investigated using UV-visible technique. Both closed and open aperture Z-scan techniques have been performed at 532 nm with pulse width 5 ns and repetition rate 10 Hz. It was found that polyethylene glycol coated magnetite exhibits reverse saturable absorption, with significant nonlinear absorption coefficient. Two-photon absorption intensity dependent positive nonlinear refraction coefficients indicate self focusing phenomena. Results show that higher concentration gives better nonlinear and optical limiting properties.

  6. Detection of poly(ethylene glycol) residues from nonionic surfactants in surface water by1h and13c nuclear magnetic resonance spectrometry

    USGS Publications Warehouse

    Leenheer, J.A.; Wershaw, R. L.; Brown, P.A.; Noyes, T.I.

    1991-01-01

    ??? Poly(ethylene glycol) (PEG) residues were detected in organic solute isolates from surface water by 1H nuclear magnetic resonance spectrometry (NMR), 13C NMR spectrometry, and colorimetric assay. PEG residues were separated from natural organic solutes in Clear Creek, CO, by a combination of methylation and chromatographic procedures. The isolated PEG residues, characterized by NMR spectrometry, were found to consist of neutral and acidic residues that also contained poly(propylene glycol) moieties. The 1H NMR and the colorimetric assays for poly(ethylene glycol) residues were done on samples collected in the lower Mississippi River and tributaries between St. Louis, MO, and New Orleans, LA, in July-August and November-December 1987. Aqueous concentrations for poly(ethylene glycol) residues based on colorimetric assay ranged from undetectable to ???28 ??g/L. Concentrations based on 1H NMR spectrometry ranged from undetectable to 145 ??g/L.

  7. Problems and solutions of polyethylene glycol co-injection method in multiresidue pesticide analysis by gas chromatography-mass spectrometry: evaluation of instability phenomenon in type II pyrethroids and its suppression by novel analyte protectants.

    PubMed

    Akutsu, Kazuhiko; Kitagawa, Yoko; Yoshimitsu, Masato; Takatori, Satoshi; Fukui, Naoki; Osakada, Masakazu; Uchida, Kotaro; Azuma, Emiko; Kajimura, Keiji

    2018-05-01

    Polyethylene glycol 300 is commonly used as a base material for "analyte protection" in multiresidue pesticide analysis via gas chromatography-mass spectrometry. However, the disadvantage of the co-injection method using polyethylene glycol 300 is that it causes peak instability in α-cyano pyrethroids (type II pyrethroids) such as fluvalinate. In this study, we confirmed the instability phenomenon in type II pyrethroids and developed novel analyte protectants for acetone/n-hexane mixture solution to suppress the phenomenon. Our findings revealed that among the examined additive compounds, three lipophilic ascorbic acid derivatives, 3-O-ethyl-L-ascorbic acid, 6-O-palmitoyl-L-ascorbic acid, and 6-O-stearoyl-L-ascorbic acid, could effectively stabilize the type II pyrethroids in the presence of polyethylene glycol 300. A mixture of the three ascorbic acid derivatives and polyethylene glycol 300 proved to be an effective analyte protectant for multiresidue pesticide analysis. Further, we designed and evaluated a new combination of analyte protectant compounds without using polyethylene glycol or the troublesome hydrophilic compounds. Consequently, we obtained a set of 10 medium- and long-chain saturated fatty acids as an effective analyte protectant suitable for acetone/n-hexane solution that did not cause peak instability in type II pyrethroids. These analyte protectants will be useful in multiresidue pesticide analysis by gas chromatography-mass spectrometry in terms of ruggedness and reliable quantitativeness. Graphical abstract Comparison of effectiveness of the addition of lipophilic derivatives of ascorbic acid in controlling the instability phenomenon of fluvalinate with polyethylene glycol 300.

  8. Affinity Electrophoresis Using Ligands Attached To Polymers

    NASA Technical Reports Server (NTRS)

    Van Alstine, James M.; Snyder, Robert S.; Harris, J. M.; Brooks, D. E.

    1990-01-01

    In new technique, reduction of electrophoretic mobilities by addition of polyethylene glycol to ligands increases electrophoretic separabilities. In immuno-affinity electrophoresis, modification of ligands extends specificity of electrophoretic separation to particles having surface electric-charge structures otherwise making them electrophoretically inseparable. Modification of antibodies by polyethylene glycol greatly reduces ability to aggregate while enhancing ability to affect electrophoretic mobilities of cells. In hydrophobic-affinity electrophoresis, addition of polyethylene glycol reduces tendency toward aggregation of cells or macromolecules.

  9. Comparison of Polyethylene Glycol-Electrolyte Solution vs Polyethylene Glycol-3350 for the Treatment of Fecal Impaction in Pediatric Patients

    PubMed Central

    Boles, Erin E.; Gaines, Cameryn L.

    2015-01-01

    OBJECTIVES: The objective of this study was to evaluate the safety and efficacy of polyethylene glycol-electrolyte solution vs polyethylene glycol-3350 for the treatment of fecal impaction in pediatric patients. METHODS: A retrospective, observational, institutional review board–approved study was conducted over a 1-year time period. Patients were included in the study if they were admitted to the hospital with a diagnosis of fecal impaction or constipation and were treated with either polyethylene glycol-electrolyte solution (PEG-ES) or polyethylene glycol-3350 (PEG-3350). Patients were excluded if they were discharged prior to resolution of treatment and/or did not receive PEG-ES or PEG-3350. RESULTS: Fifty-one patients (ranging in age from 1 month to 15 years) were evaluated: 23 patients received PEG-ES and 28 patients received PEG-3350. Sex, race, age, and weight were not statistically different between the 2 groups. Resolution of fecal impaction was not significantly different between PEG-ES vs PEG-3350 (87% and 86%, respectively; p = 0.87). There was only 1 reported side effect with PEG-3350, vs 11 reported side effects with PEG-ES (p < 0.01). CONCLUSIONS: Theses results suggest that PEG-3350 is as effective as PEG-ES for the treatment of fecal impaction in pediatric patients and is associated with fewer side effects. PMID:26170773

  10. Comparison of Polyethylene Glycol-Electrolyte Solution vs Polyethylene Glycol-3350 for the Treatment of Fecal Impaction in Pediatric Patients.

    PubMed

    Boles, Erin E; Gaines, Cameryn L; Tillman, Emma M

    2015-01-01

    The objective of this study was to evaluate the safety and efficacy of polyethylene glycol-electrolyte solution vs polyethylene glycol-3350 for the treatment of fecal impaction in pediatric patients. A retrospective, observational, institutional review board-approved study was conducted over a 1-year time period. Patients were included in the study if they were admitted to the hospital with a diagnosis of fecal impaction or constipation and were treated with either polyethylene glycol-electrolyte solution (PEG-ES) or polyethylene glycol-3350 (PEG-3350). Patients were excluded if they were discharged prior to resolution of treatment and/or did not receive PEG-ES or PEG-3350. Fifty-one patients (ranging in age from 1 month to 15 years) were evaluated: 23 patients received PEG-ES and 28 patients received PEG-3350. Sex, race, age, and weight were not statistically different between the 2 groups. Resolution of fecal impaction was not significantly different between PEG-ES vs PEG-3350 (87% and 86%, respectively; p = 0.87). There was only 1 reported side effect with PEG-3350, vs 11 reported side effects with PEG-ES (p < 0.01). Theses results suggest that PEG-3350 is as effective as PEG-ES for the treatment of fecal impaction in pediatric patients and is associated with fewer side effects.

  11. 40 CFR 721.9516 - Siloxanes and silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-aminoethyl) amino]propyl Me, di-Me, reaction products with polyethylene-polypropylene glycol Bu glycidal..., reaction products with polyethylene-polypropylene glycol Bu glycidal ether. (a) Chemical substance and... silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with polyethylene-polypropylene...

  12. 40 CFR 721.9516 - Siloxanes and silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-aminoethyl) amino]propyl Me, di-Me, reaction products with polyethylene-polypropylene glycol Bu glycidal..., reaction products with polyethylene-polypropylene glycol Bu glycidal ether. (a) Chemical substance and... silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with polyethylene-polypropylene...

  13. Polyethylene glycol 3350 without electrolytes for treatment of childhood constipation

    PubMed Central

    Chung, Seen; Cheng, Adam; Goldman, Ran D.

    2009-01-01

    ABSTRACT QUESTION I have come across many pediatric patients with functional constipation. Is polyethylene glycol 3350 without electrolytes a safe and effective long-term treatment option for these patients? ANSWER Functional constipation is a common and often difficult problem for parents and families to deal with. Polyethylene glycol 3350 is a safe and effective long-term laxative in pediatric populations, but there are limited studies for its use in children younger than 2 years of age. PMID:19439699

  14. Solubility of pioglitazone hydrochloride in binary mixtures of polyethylene glycol 400 with ethanol, propylene glycol, N-methyl-2-pyrrolidone, and water at 25 degrees C.

    PubMed

    Jouyban, Abolghasem; Soltanpour, Shahla

    2010-09-01

    The solubility of pioglitazone hydrochloride in binary mixtures of polyethylene glycol 400 with ethanol, N-methyl-2-pyrrolidone, propylene glycol, and water at 25 degrees C are reported. The generated data are fitted to the Jouyban-Acree model and the mean relative deviations are 2.6%, 1.5%, 5.8%, and 7.4%, respectively for ethanol, N-methyl-2-pyrrolidone, propylene glycol, and water.

  15. Crystallization Kinetics of Indomethacin/Polyethylene Glycol Dispersions Containing High Drug Loadings.

    PubMed

    Duong, Tu Van; Van Humbeeck, Jan; Van den Mooter, Guy

    2015-07-06

    The reproducibility and consistency of physicochemical properties and pharmaceutical performance are major concerns during preparation of solid dispersions. The crystallization kinetics of drug/polyethylene glycol solid dispersions, an important factor that is governed by the properties of both drug and polymer has not been adequately explored, especially in systems containing high drug loadings. In this paper, by using standard and modulated differential scanning calorimetry and X-ray powder diffraction, we describe the influence of drug loading on crystallization behavior of dispersions made up of indomethacin and polyethylene glycol 6000. Higher drug loading increases the amorphicity of the polymer and inhibits the crystallization of PEG. At 52% drug loading, polyethylene glycol was completely transformed to the amorphous state. To the best of our knowledge, this is the first detailed investigation of the solubilization effect of a low molecular weight drug on a semicrystalline polymer in their dispersions. In mixtures containing up to 55% indomethacin, the dispersions exhibited distinct glass transition events resulting from amorphous-amorphous phase separation which generates polymer-rich and drug-rich domains upon the solidification of supercooled polyethylene glycol, whereas samples containing at least 60% drug showed a single amorphous phase during the period in which crystallization normally occurs. The current study demonstrates a wide range in physicochemical properties of drug/polyethylene glycol solid dispersions as a result of the complex nature in crystallization of this system, which should be taken into account during preparation and storage.

  16. FTIR studies on the effect of concentration of polyethylene glycol on polimerization of Shellac

    NASA Astrophysics Data System (ADS)

    Khairuddin; Pramono, E.; Utomo, S. B.; Wulandari, V.; Zahrotul W, A.; Clegg, F.

    2016-11-01

    In the present paper, it was reported the FTIR studies on the efect of polyethylene glycol on polimerization of shellac. The shellac was shellac waxfree, and the solvent was ethanol 96%. The shellac films were were prepared by solvent- evaporation method. The concentrations of polyethylene glycol having molecular weight of 400 were 10, 30, 60, and 90 w/w %. Three peak intensity bands of C= O stretching of ester at 1709 cm-1, O-H stretching of hydroxyl group at 3400 cm-1, and C-H stretching vibration at 2942 cm-1 were observed and related to polimerization of shellac. It was found that polymerization of shellac was slowed down by polyethyelene glycol, and the degree of polymerization of shellac decreased with increasing the concentration of polyethyelene glycol.

  17. 21 CFR 349.12 - Ophthalmic demulcents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... percent. (2) Hydroxyethyl cellulose, 0.2 to 2.5 percent. (3) Hypromellose, 0.2 to 2.5 percent. (4...) Polyethylene glycol 300, 0.2 to 1 percent. (3) Polyethylene glycol 400, 0.2 to 1 percent. (4) Polysorbate 80, 0.2 to 1 percent. (5) Propylene glycol, 0.2 to 1 percent. (e) Polyvinyl alcohol, 0.1 to 4 percent. (f...

  18. 21 CFR 349.12 - Ophthalmic demulcents.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... percent. (2) Hydroxyethyl cellulose, 0.2 to 2.5 percent. (3) Hypromellose, 0.2 to 2.5 percent. (4...) Polyethylene glycol 300, 0.2 to 1 percent. (3) Polyethylene glycol 400, 0.2 to 1 percent. (4) Polysorbate 80, 0.2 to 1 percent. (5) Propylene glycol, 0.2 to 1 percent. (e) Polyvinyl alcohol, 0.1 to 4 percent. (f...

  19. Early, patient-initiated treatment of herpes labialis with topical 10% acyclovir.

    PubMed Central

    Spruance, S L; Crumpacker, C S; Schnipper, L E; Kern, E R; Marlowe, S; Arndt, K A; Overall, J C

    1984-01-01

    To determine whether topical acyclovir in polyethylene glycol could reduce the severity of herpes simplex labialis if applied immediately after onset of a recurrence, 10% acyclovir in polyethylene glycol ointment or polyethylene glycol alone was prospectively dispensed to 352 patients in a double-blind, randomized trial. Sixty-nine subjects initiated treatment in the prodrome (57%) or erythema (43%) stage and were followed by clinical and virological criteria. The healing time (6.0 days), maximum lesion area (42 mm2), vesicle or ulcer formation (91%), and maximum lesion virus titer (4.8 log10 PFU) in the drug recipients were not reduced in comparison with those who received the vehicle (5.2 days, 30 mm2, 75%, and 4.5 log10 PFU, respectively). Topical acyclovir in polyethylene glycol was ineffective for the treatment of herpes labialis despite an optimum therapeutic opportunity. PMID:6732224

  20. Raman analysis of polyethylene glycols and polyethylene oxides

    NASA Astrophysics Data System (ADS)

    Sagitova, E. A.; Prokhorov, K. A.; Nikolaeva, G. Yu; Baimova, A. V.; Pashinin, P. P.; Yarysheva, A. Yu; Mendeleev, D. I.

    2018-04-01

    We present Raman study of commercial liquids and powders of polyethylene glycols and polyethylene oxides with the average molecular weight from 400 Da to 10000 kDa. The most significant spectral changes were observed for the range of the molecular weights, where the liquid/semisolid transition has occurred. For the powders we revealed increase in the content of the molecules in the helical conformation and in the content of the monoclinic crystalline phase with growth of the molecular weight.

  1. Polyethylene Glycol Based Graphene Aerogel Confined Phase Change Materials with High Thermal Stability.

    PubMed

    Fu, Yang; Xiong, Weilai; Wang, Jianying; Li, Jinghua; Mei, Tao; Wang, Xianbao

    2018-05-01

    Polyethylene glycol (PEG) based graphene aerogel (GA) confined shaped-stabilized phase change materials (PCMs) are simply prepared by a one-step hydrothermal method. Three-dimensional GA inserted by PEG molecule chains, as a supporting material, obtained by reducing graphene oxide sheets, is used to keep their stabilized shape during a phase change process. The volume of GA is obviously expended after adding PEG, and only 9.8 wt% of GA make the composite achieve high energy efficiency without leakage during their phase change because of hydrogen bonding widely existing in the GA/PEG composites (GA-PCMs). The heat storage energy of GA-PCMs is 164.9 J/g, which is 90.2% of the phase change enthalpy of pure PEG. In addition, this composite inherits the natural thermal properties of graphene and thus shows enhanced thermal conductivity compared with pure PEG. This novel study provides an efficient way to fabricate shape-stabilized PCMs with a high content of PEG for thermal energy storage.

  2. The effect of polyethylene glycol on the characteristics of kenaf cellulose/low-density polyethylene biocomposites.

    PubMed

    Tajeddin, Behjat; Rahman, Russly Abdul; Abdulah, Luqman Chuah

    2010-08-01

    Toward the development of biocomposites for packaging applications, the possibility of using kenaf cellulose (KC) was investigated in the production of low-density polyethylene (LDPE)/KC/polyethylene glycol (PEG) biocomposites. First, cellulose was extracted from the cell walls of kenaf-bast fibers. Then, different weights of LDPE, KC, and PEG were blended, and the effects of varying the concentrations of KC and PEG on the synthesis process were evaluated, and the resulting composites were characterized with respect to their mechanical, thermal, biodegradability and water-absorption properties. A scanning electron microscope (SEM) was also used to observe the surface morphology of the samples before and after biodegradation tests. The results showed that the mechanical properties of the biocomposites decreased slightly as the KC content was increased from 0 to 50wt% in the biocomposite formulation; however, there was a good homogeneity between samples with added PEG. The addition of KC improved the thermal resistance of these biocomposites; PEG also had positive role in the thermal behavior of the composites. Based on a soil-burial test, the biodegradability of the composites showed a clear trend of increase degradation with increasing KC content in the formulation. While water-absorption values for the composites were higher than that of pure LDPE polymer, the addition of PEG to the formulation reduced the water absorption of the composites. Copyright 2010 Elsevier B.V. All rights reserved.

  3. Bactericidal activity of propylene glycol, glycerine, polyethylene glycol 400, and polyethylene glycol 1000 against selected microorganisms

    PubMed Central

    Nalawade, Triveni Mohan; Bhat, Kishore; Sogi, Suma H. P.

    2015-01-01

    Aim: The aim of the present study was to evaluate the bactericidal activity of propylene glycol, glycerine, polyethylene glycol 400 (PEG 400), and polyethylene glycol 1000 (PEG 1000) against selected microorganisms in vitro. Materials and Methods: Five vehicles, namely propylene glycol, glycerine, PEG 400, PEG 1000, and combination of propylene glycol with PEG 400, were tested for their bactericidal activity. The minimum bactericidal concentration was noted against four standard strains of organisms, i.e. Streptococcus mutans American Type Culture Collection (ATCC) 25175, Streptococcus mutans ATCC 12598, Enterococcus faecalis ATCC 35550, and Escherichia coli ATCC 25922, using broth dilution assay. Successful endodontic therapy depends upon thorough disinfection of root canals. In some refractory cases, routine endodontic therapy is not sufficient, so intracanal medicaments are used for proper disinfection of canals. Intracanal medicaments are dispensed with vehicles which aid in increased diffusion through the dentinal tubules and improve their efficacy. Among the various vehicles used, glycerine is easily available, whereas others like propylene glycol and polyethylene glycol have to be procured from appropriate sources. Also, these vehicles, being viscous, aid in sustained release of the medicaments and improve their handling properties. The most commonly used intracanal medicaments like calcium hydroxide are ineffective on many microorganisms, while most of the other medicaments like MTAD (Mixture of Tetracycline, an Acid, and a Detergent) and Triple Antibiotic Paste (TAP) consist of antibiotics which can lead to development of antibiotic resistance among microorganisms. Thus, in order to use safer and equally effective intracanal medicaments, newer alternatives like chlorhexidine gluconate, ozonized water, etc., are being explored. Similarly, the five vehicles mentioned above are being tested for their antimicrobial activity in this study. Results: All vehicles exhibited bactericidal activity at 100% concentration. Conclusion: Propylene glycol was effective against three organisms namely S. mutans E. faecalis and E. coli and its bactericidal activity was at 50%, 25% and 50% respectively. PEG 1000 was effective against S. mutans and E. coli at 25%. Hence propylene glycol was effective on more number of organisms of which E. faecalis is a known resistant species. PEG 1000 was bactericidal at a lower concentration but was effective on two organisms only. PMID:25992336

  4. Bactericidal activity of propylene glycol, glycerine, polyethylene glycol 400, and polyethylene glycol 1000 against selected microorganisms.

    PubMed

    Nalawade, Triveni Mohan; Bhat, Kishore; Sogi, Suma H P

    2015-01-01

    The aim of the present study was to evaluate the bactericidal activity of propylene glycol, glycerine, polyethylene glycol 400 (PEG 400), and polyethylene glycol 1000 (PEG 1000) against selected microorganisms in vitro. Five vehicles, namely propylene glycol, glycerine, PEG 400, PEG 1000, and combination of propylene glycol with PEG 400, were tested for their bactericidal activity. The minimum bactericidal concentration was noted against four standard strains of organisms, i.e. Streptococcus mutans American Type Culture Collection (ATCC) 25175, Streptococcus mutans ATCC 12598, Enterococcus faecalis ATCC 35550, and Escherichia coli ATCC 25922, using broth dilution assay. Successful endodontic therapy depends upon thorough disinfection of root canals. In some refractory cases, routine endodontic therapy is not sufficient, so intracanal medicaments are used for proper disinfection of canals. Intracanal medicaments are dispensed with vehicles which aid in increased diffusion through the dentinal tubules and improve their efficacy. Among the various vehicles used, glycerine is easily available, whereas others like propylene glycol and polyethylene glycol have to be procured from appropriate sources. Also, these vehicles, being viscous, aid in sustained release of the medicaments and improve their handling properties. The most commonly used intracanal medicaments like calcium hydroxide are ineffective on many microorganisms, while most of the other medicaments like MTAD (Mixture of Tetracycline, an Acid, and a Detergent) and Triple Antibiotic Paste (TAP) consist of antibiotics which can lead to development of antibiotic resistance among microorganisms. Thus, in order to use safer and equally effective intracanal medicaments, newer alternatives like chlorhexidine gluconate, ozonized water, etc., are being explored. Similarly, the five vehicles mentioned above are being tested for their antimicrobial activity in this study. All vehicles exhibited bactericidal activity at 100% concentration. Propylene glycol was effective against three organisms namely S. mutans E. faecalis and E. coli and its bactericidal activity was at 50%, 25% and 50% respectively. PEG 1000 was effective against S. mutans and E. coli at 25%. Hence propylene glycol was effective on more number of organisms of which E. faecalis is a known resistant species. PEG 1000 was bactericidal at a lower concentration but was effective on two organisms only.

  5. Molecularly uniform poly(ethylene glycol) certified reference material

    NASA Astrophysics Data System (ADS)

    Takahashi, Kayori; Matsuyama, Shigetomo; Kinugasa, Shinichi; Ehara, Kensei; Sakurai, Hiromu; Horikawa, Yoshiteru; Kitazawa, Hideaki; Bounoshita, Masao

    2015-02-01

    A certified reference material (CRM) for poly(ethylene glycol) with no distribution in the degree of polymerization was developed. The degree of polymerization of the CRM was accurately determined to be 23. Supercritical fluid chromatography (SFC) was used to separate the molecularly uniform polymer from a standard commercial sample with wide polydispersity in its degree of polymerization. Through the use of a specific fractionation system coupled with SFC, we are able to obtain samples of poly(ethylene glycol) oligomer with exact degrees of polymerization, as required for a CRM produced by the National Metrology Institute of Japan.

  6. Short-term rescue of neonatal lethality in a mouse model of propionic acidemia by gene therapy.

    PubMed

    Hofherr, Sean E; Senac, Julien S; Chen, Christopher Y; Palmer, Donna J; Ng, Philip; Barry, Michael A

    2009-02-01

    Propionic acidemia (PA) is a metabolic disorder that causes mental retardation and that can be fatal if untreated. PA is inherited in an autosomal recessive fashion involving mutations in PCCA or PCCB encoding the alpha and beta subunits of propionyl-CoA carboxylase (PCC). Current treatment is based on dietary restriction of substrate amino acids, which attenuates symptoms. However, patients still experience episodes of hyperammonemia that can cause progressive neurologic damage. In this paper, we have tested gene therapy approaches to PA in a stringent mouse model of PCCA deficiency, in which homozygous knockout mice are born but die within 36 hr. In this work, we have delivered first-generation and helper-dependent adenovirus serotype 5 (Ad5) vectors expressing the human PCCA cDNA by intraperitoneal injection into newborn mice. Unmodified Ad5 vectors mediated extensive transduction of the peritoneum with weak liver transduction as determined by luciferase imaging and dsRed expression. In contrast, modification of Ad5 with polyethylene glycol detargeted the virus from the peritoneum and retargeted it for transduction in the liver. When vectors expressing PCCA were injected, significant increases in life span were observed for both the unmodified and polyethylene glycol (PEG)-modified Ad5 vectors. However, this rescue was transient. Similarly, adeno-associated virus serotype 8-mediated transduction also produced only transient rescue. These data show first proof of principle for gene therapy of PA and demonstrate the potential utility of PEG to modify viral tropism in an actual gene therapy application.

  7. 40 CFR 721.7255 - Polyethyleneamine crosslinked with substituted polyethylene glycol (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.7255 Polyethyleneamine crosslinked with substituted polyethylene glycol (generic). (a) Chemical substance and significant new uses subject to...

  8. Comparison of biodegradation of poly(ethylene glycol)s and poly(propylene glycol)s.

    PubMed

    Zgoła-Grześkowiak, Agnieszka; Grześkowiak, Tomasz; Zembrzuska, Joanna; Łukaszewski, Zenon

    2006-07-01

    The biodegradation of poly(ethylene glycol)s (PEGs) and poly(propylene glycol)s (PPGs), both being major by-products of non-ionic surfactants biodegradation, was studied under the conditions of the River Water Die-Away Test. PEGs were isolated from a water matrix using solid-phase extraction with graphitized carbon black sorbent, then derivatized with phenyl isocyanate and determined by HPLC with UV detection. PPGs were isolated from a water matrix by liquid-liquid extraction with chloroform, then derivatized with naphthyl isocyanate and determined by HPLC with fluorescence detection. The primary biodegradation of both PEGs and PPGs reached approximately 99% during the test. The tests show different biodegradation pathways of PEG and PPG. During PEG biodegradation, their chains are shortened leading to the formation of ethylene glycol and diethylene glycol. During PPG biodegradation, no short-chained biodegradation products were found.

  9. Ketoprofen suppository dosage forms: in vitro release and in vivo absorption studies in rabbits.

    PubMed

    Babar, A; Bellete, T; Plakogiannis, F M

    1999-02-01

    In vitro release of ketoprofen from suppository bases and in vivo absorption in rabbits were studied. Suppositories containing 50 mg of ketoprofen were prepared using theobroma oil, esterified (c10-c18) fatty acids, and polyethylene glycol 1000 bases. The displacement values of the drug were determined and found to be of the order of theobroma oil > esterified (c10-c18) fatty acids and polyethylene glycol 1000 bases. The suppository hardness data revealed that the theobroma oil base produced relatively brittle suppositories. Using the USP dissolution method, the release of ketoprofen was observed to be greatest from polyethylene glycol 1000 suppositories. With the dialysis technique, the maximum release of drug was obtained from theobroma oil suppository containing polysorbate 40 at a 6% level. Selected suppository formulations were evaluated for rectal absorption studies in rabbits. The in vivo data showed that the optimum drug absorption took place from the polyethylene glycol 1000 base and theobroma oil formulation containing 6% polysorbate 40.

  10. Improving amphiphilic polypropylenes by grafting poly(vinylpyrrolidone) and poly(ethylene glycol) methacrylate segments on a polypropylene microporous membrane

    NASA Astrophysics Data System (ADS)

    Chen, Huirong; Ma, Wenzhong; Xia, Yanping; Gu, Yi; Cao, Zheng; Liu, Chunlin; Yang, Haicun; Tao, Shengxi; Geng, Haoran; Tao, Guoliang; Matsuyama, Hideto

    2017-10-01

    An amphiphilic polypropylene-g-poly[vinylpyrrolidone-co-poly(ethylene glycol) methacrylate] (PP-g-(NVP-co-PEGMA)) modifier was prepared by melt grafting polymerization using N-vinyl pyrrolidone (NVP) as the grafting monomer and poly(ethylene glycol) (PEGMA) as the comonomer. Fourier transform infrared (FTIR) spectroscopy and elemental analysis showed that the hydrophilic branched chains (NVP-g-PEGMA) were successfully grafted to polypropylene (PP) macromolecular chains. The largest NVP grafting degree for PP-g-(NVP-co-PEGMA) (up to 20.4%) was obtained when the mass ratio of PP/NVP/PEGMA was 100/30/15. Hydrophilic PP microporous membranes were prepared by stretching cast films of PP/PP-g-(NVP-co-PEGMA) blends. The membrane thermostability (including the modifier) was better than that of the pure PP membrane with a similar surface pore structure. The porosity of the modified membranes was only slightly lower than that of the pure PP membranes. Contact angle measurements were used to examine the hydrophilicity of the membranes. The water contact angle of the membranes decreased when PP-g-(NVP-co-PEGMA) was added, and the minimum contact angle was 64.5°. Therefore, this work provides a good application for stretched hydrophilic PP membrane fabrication.

  11. 21 CFR 178.3760 - Polyethylene glycol (400) monolaurate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Polyethylene glycol (400) monolaurate. 178.3760 Section 178.3760 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND...

  12. Development of controlled release formulations of azadirachtin-A employing poly(ethylene glycol) based amphiphilic copolymers.

    PubMed

    Kumar, Jitendra; Shakil, Najam A; Singh, Manish K; Singh, Mukesh K; Pandey, Alka; Pandey, Ravi P

    2010-05-01

    Controlled release (CR) formulations of azadirachtin-A, a bioactive constituent derived from the seed of Azadirachta indica A. Juss (Meliaceae), have been prepared using commercially available polyvinyl chloride, polyethylene glycol (PEG) and laboratory synthesized poly ethylene glycol-based amphiphilic copolymers. Copolymers of polyethylene glycol and various dimethyl esters, which self assemble into nano micellar aggregates in aqueous media, have been synthesized. The kinetics of azadirachtin-A, release in water from the different formulations was studied. Release from the commercial polyethylene glycol (PEG) formulation was faster than the other CR formulations. The rate of release of encapsulated azadirachtin-A from nano micellar aggregates is reduced by increasing the molecular weight of PEG. The diffusion exponent (n value) of azadirachtin-A, in water ranged from 0.47 to 1.18 in the tested formulations. The release was diffusion controlled with a half release time (t(1/2)) of 3.05 to 42.80 days in water from different matrices. The results suggest that depending upon the polymer matrix used, the application rate of azadirachtin-A can be optimized to achieve insect control at the desired level and period.

  13. Synthesis and characterization of titanium dioxide (TiO2) nanopowder

    NASA Astrophysics Data System (ADS)

    Munirah, S.; Nadzirah, Sh.; Khusaimi, Z.; Fazlena, H.; Rusop, M.

    2018-05-01

    Titanium dioxide (TiO2) powder was synthesized via sol-gel technique using Titanium tetraisopropoxide (TTIP) and ethanol as precursors. Acetylacetone, distilled water, polyethylene glycol (PEG) and stabilizers (glacial acetic acid and nitric acid) were then added to the solution. The solution was left for ageing for 24 hours and then dried into powder. The synthesized powders were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TGA).

  14. Comparison of polyethylene glycol 3350 and lactulose for treatment of chronic constipation in children.

    PubMed

    Gremse, David A; Hixon, Jamie; Crutchfield, Alysia

    2002-05-01

    Polyethylene glycol (PEG) 3350 and lactulose were compared in an unblinded, randomized, crossover design for treatment of constipation in 37 children aged 2 to 16 years. Subjects received lactulose (1.3 g/kg/d divided twice daily up to 20 g) or PEG 3350 (10 g/m2/day) for 2 weeks. PEG 3350 significantly decreased the total colonic transit time compared to lactulose (47.6+/-2.7 vs 55.3+/-2.4 hours, mean +/- SE, PEG 3350 vs lactulose, respectively, p = 0.038). The stool frequency, form, and the ease of passage were similar for each laxative. Polyethylene glycol 3350 is an effective laxative for the treatment of chronic constipation in children.

  15. Improved enzymatic hydrolysis of microcrystalline cellulose (Avicel PH101) by polyethylene glycol addition.

    PubMed

    Ouyang, Jia; Dong, Zhenwei; Song, Xiangyang; Lee, Xin; Chen, Mu; Yong, Qiang

    2010-09-01

    The effects of additives on hydrolysis of microcrystalline cellulose (Avicel PH101) were examined using commercial cellulose-degrading enzymes (Celluclast 1.5L and Novozyme 188). Polyethylene glycol 4000 (PEG4000) was the most effective additive tested. When PEG4000 was added at 0.05 g/g glucan, the conversion of Avicel PH101 increased 91% (from 41.1% to 78.9%). The cellulase activity of Celluclast 1.5L increased 27.5% with PEG4000 addition. A positive effect on enzyme stabilities of Celluclast 1.5L and Novozyme 188 also occurred with PEG4000 addition. During hydrolysis process, significant changes in free protein concentration and cellulase activity were observed on Avicel PH101. More than 90% of the original enzyme activity remained in the solution after 48 h hydrolysis. Thus, PEG4000 addition is an efficient method to enhance digestibility of cellulosic materials and make enzyme recovery possible and valuable. This provides an opportunity of decreasing the operational cost of the hydrolysis process. (c) 2010 Elsevier Ltd. All rights reserved.

  16. Nanosilica sol leads to further increase in polyethylene glycol (PEG) 1000-enhanced thermostability of β-cyclodextrin glycosyltransferase from Bacillus circulans.

    PubMed

    Li, Caiming; Huang, Min; Gu, Zhengbiao; Hong, Yan; Cheng, Li; Li, Zhaofeng

    2014-04-02

    A major disadvantage of cyclodextrin production is the limited thermostability of cyclodextrin glycosyltransferase. The ability of combinations of nanosilica sol with polyethylene glycol (PEG) 1000 to enhance the thermostability of the β-cyclodextrin glycosyltransferase from Bacillus circulans was investigated. It was found that 10% PEG 1000 combined with 0.05% nanosilica sol could activate the β-cyclodextrin glycosyltransferase by 17.2%. Furthermore, 0.05% nanosilica sol leads to further increase in PEG 1000-enhanced thermostability of β-cyclodextrin glycosyltransferase. With the simultaneous addition of 10% PEG 1000 and 0.05% nanosilica into the enzyme solution, which was allowed to incubate for 60 min at 60 °C, 61.3% of β-cyclodextrin-forming activity could be retained, which was much higher than that with only 10% PEG 1000 added. Atomic force microscopy, fluorescence spectroscopy, and circular dichroism analysis indicated that silica nanoparticles helped PEG 1000 further protect the tertiary and secondary structures of β-cyclodextrin glycosyltransferase. This study provides an effective approach for improving the thermostability of cyclodextrin glycosyltransferase and related enzymes.

  17. 21 CFR 178.3750 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... used in food-packaging adhesives complying with § 175.105 of this chapter. ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Polyethylene glycol (mean molecular weight 200-9,500). 178.3750 Section 178.3750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND...

  18. 21 CFR 178.3760 - Polyethylene glycol (400) monolaurate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Polyethylene glycol (400) monolaurate. 178.3760 Section 178.3760 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... be used for tying meat provided the twine fibers are produced from nylon resins complying with § 177...

  19. Soft and flexible poly(ethylene glycol) nanotubes for local drug delivery.

    PubMed

    Newland, B; Taplan, C; Pette, D; Friedrichs, J; Steinhart, M; Wang, W; Voit, B; Seib, F P; Werner, C

    2018-05-10

    Nanotubes are emerging as promising materials for healthcare applications but the selection of clinically relevant starting materials for their synthesis remains largely unexplored. Here we present, for the first time, the synthesis of poly(ethylene glycol) (PEG) based nanotubes via the photopolymerization of poly(ethylene glycol) diacrylate and other diacrylate derivatives within the pores of anodized aluminum oxide templates. Template-assisted synthesis allowed the manufacture of a diverse set of polymeric nanotubes with tunable physical characteristics including diameter (∼200-400 nm) and stiffness (405-902 kPa). PEG nanotubes were subjected to cytotoxicty assessment in cell lines and primary stem cells and showed excellent cytocompatability (IC50 > 120 μg ml-1). Nanotubes were readily drug loaded but released the majority of the drug over 5 days. Direct administration of drug loaded nanotubes to human orthotopic breast tumors substantially reduced tumor growth and metastasis and outperformed i.v. administration at the equivalent dose. Overall, this nanotube templating platform is emerging as a facile route for the manufacture of poly(ethylene glycol) nanotubes.

  20. Study of Synthesis Polyethylene glycol oleate Sulfonated as an Anionic Surfactant for Enhanced Oil Recovery (EOR)

    NASA Astrophysics Data System (ADS)

    Sampora, Yulianti; Juwono, Ariadne L.; Haryono, Agus; Irawan, Yan

    2017-11-01

    Mechanical Enhanced Oil Recovery (EOR) through chemical injection is using an anionic surfactant to improve the recovery of oil residues, particularly in a reservoir area that has certain characteristics. This case led the authors to conduct research on the synthesis of an anionic surfactant based on oleic acid and polyethylene glycol 400 that could be applied as a chemical injection. In this work, we investigate the sulfonation of Polyethylene glycol oleate (PDO) in a sulfuric acid agent. PDO in this experiment was derived from Indonesian palm oil. Variation of mole reactant and reaction time have been studied. The surfactant has been characterized by measuring the interfacial tension, acid value, ester value, saponification value, iodine value, Fourier Transform Infrared (FTIR), and particle size analyzer. There is a new peak at 1170-1178 cm-1 indicating that S=O bond has formed. PDO sulfonate exhibits good surface activity due to interfacial tension of 0,003 mN/m. Thus, polyethylene glycol oleate sulfonate was successfully synthesized and it could be useful as a novel an anionic surfactant.

  1. Amperometric Biosensor Based on Zirconium Oxide/Polyethylene Glycol/Tyrosinase Composite Film for the Detection of Phenolic Compounds.

    PubMed

    Ahmad, Nor Monica; Abdullah, Jaafar; Yusof, Nor Azah; Ab Rashid, Ahmad Hazri; Abd Rahman, Samsulida; Hasan, Md Rakibul

    2016-06-29

    A phenolic biosensor based on a zirconium oxide/polyethylene glycol/tyrosinase composite film for the detection of phenolic compounds has been explored. The formation of the composite film was expected via electrostatic interaction between hexacetyltrimethylammonium bromide (CTAB), polyethylene glycol (PEG), and zirconium oxide nanoparticles casted on screen printed carbon electrode (SPCE). Herein, the electrode was treated by casting hexacetyltrimethylammonium bromide on SPCE to promote a positively charged surface. Later, zirconium oxide was mixed with polyethylene glycol and the mixture was dropped cast onto the positively charged SPCE/CTAB. Tyrosinase was further immobilized onto the modified SPCE. Characterization of the prepared nanocomposite film and the modified SPCE surface was investigated by scanning electron microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), and Cyclic voltamogram (CV). The developed biosensor exhibits rapid response for less than 10 s. Two linear calibration curves towards phenol in the concentrations ranges of 0.075-10 µM and 10-55 µM with the detection limit of 0.034 µM were obtained. The biosensor shows high sensitivity and good storage stability for at least 30 days.

  2. Poly(ethylene glycol)s as grinding additives in the mechanochemical preparation of highly functionalized 3,5-disubstituted hydantoins.

    PubMed

    Mascitti, Andrea; Lupacchini, Massimiliano; Guerra, Ruben; Taydakov, Ilya; Tonucci, Lucia; d'Alessandro, Nicola; Lamaty, Frederic; Martinez, Jean; Colacino, Evelina

    2017-01-01

    The mechanochemical preparation of highly functionalized 3,5-disubstituted hydantoins was investigated in the presence of various poly(ethylene) glycols (PEGs), as safe grinding assisting agents (liquid-assisted grinding, LAG). A comparative study under dry-grinding conditions was also performed. The results showed that the cyclization reaction was influenced by the amount of the PEG grinding agents. In general, cleaner reaction profiles were observed in the presence of PEGs, compared to dry-grinding procedures.

  3. Poly(ethylene glycol)s as grinding additives in the mechanochemical preparation of highly functionalized 3,5-disubstituted hydantoins

    PubMed Central

    Guerra, Ruben; Taydakov, Ilya; Tonucci, Lucia; d’Alessandro, Nicola; Lamaty, Frederic; Martinez, Jean

    2017-01-01

    The mechanochemical preparation of highly functionalized 3,5-disubstituted hydantoins was investigated in the presence of various poly(ethylene) glycols (PEGs), as safe grinding assisting agents (liquid-assisted grinding, LAG). A comparative study under dry-grinding conditions was also performed. The results showed that the cyclization reaction was influenced by the amount of the PEG grinding agents. In general, cleaner reaction profiles were observed in the presence of PEGs, compared to dry-grinding procedures. PMID:28179944

  4. Preparation and characterization of PVDF separators for lithium ion cells using hydroxyl-terminated polybutadiene grafted methoxyl polyethylene glycol (HTPB-g-MPEG) as additive

    NASA Astrophysics Data System (ADS)

    Li, Hao; Niu, Dong-Hui; Zhou, Hui; Chao, Chun-Ying; Wu, Li-Jun; Han, Pei-Lin

    2018-05-01

    Hydroxyl-terminated polybutadiene grafted methoxyl polyethylene glycol (HTPB-g-MPEG) with different arm length were synthesized by grafting methoxyl poly(ethylene glycol)s (MPEGs, Mn = 350, 750, 1900 and 5000, respectively) to the hydroxyl-terminated polybutadiene (HTPB) molecule using isophorone diisocyanate (IPDI) as the coupling agent, and blended with PVDF to fabricate porous separators via phase inversion process. By measuring the composition, morphology and ion conductivity etc., the influence of HTPB-g-MPEG on structure and property of blend separators were discussed. Compared with pure PVDF separator with comparable porous structure, the adoption of HTPB-g-MPEG could not only decrease the crystallinity, but also enhance the stability of entrapped liquid electrolyte and corresponding ion conductivity. The cells assembled with such separators showed good initial discharge capacity and cyclic stability.

  5. Randomized cross-over trial of polyethylene glycol electrolyte solution and water for colostomy irrigation.

    PubMed

    O'Bichere, Austin; Green, Colin; Phillips, Robin K S

    2004-09-01

    Water for colostomy irrigation is largely absorbed by the colon, which may result in less efficient expulsion of stool. This study compared the outcome of colonic cleansing with water and polyethylene glycol solution. In a cross-over study, 41 colostomy irrigators were randomly assigned to water or polyethylene glycol solution irrigation first and then the other regimen, each for one week. Patients recorded fluid inflow time, total washout time, cramps, leakage episodes, number of stoma pouches used, and satisfaction scores (Visual Analog Scale, 1-10: 1 = poor, and 10 = excellent). The median and interquartile range for each variable was calculated, and the two treatments were compared (Wilcoxon's test). Eight patients failed to complete the study. Thirty-three patients (20 females; mean age, 55 (range, 39-73) years) provided 352 irrigation sessions: water (n = 176), and polyethylene glycol solution (n = 176). Irrigation was performed every 24, 48, and 72 hours by 17, 9, and 7 patients respectively, using 500 ml (n = 1), 750 ml (n = 2), 1,000 ml (n = 16), 1,500 ml (n = 11), 2,000 ml (n = 2), and 3,500 ml (n = 1) of fluid. The median and interquartile range for water vs. polyethylene glycol solution were: fluid inflow time (6 (range, 4.4-10.8) vs. 6.3 (range, 4.1-11) minutes; P = 0.48), total washout time (53 (range, 33-69) vs. 38 (range, 28-55) minutes; P = 0.01), leakage episodes (2.3 (range, 1.7-3.8) vs. 0.7 (range, 0.2-1); P < 0.001), satisfaction score (5.8 (range, 4-7.5) vs. 8.8 (range, 8.3-10); P < 0.001), and stoma pouch usage per week (75 (range, 45-80) vs. 43 (range, 0-80); P = 0.008). No difference was demonstrated for frequency of cramps ( P = 0.24). Polyethylene glycol solution performed significantly better than water and may be a superior alternative fluid regimen for colostomy irrigation.

  6. Preparation of Hybrid Nanoparticle Nucleating Agents and Their Effects on the Crystallization Behavior of Poly(ethylene terephthalate)

    PubMed Central

    Han, Zhenzhen; Wang, Yao; Wang, Jiuxing; Wang, Shichao; Zhuang, Hongwei; Liu, Jixian; Huang, Linjun; Wang, Yanxin; Wang, Wei; Belfiore, Laurence A.; Tang, Jianguo

    2018-01-01

    In this research contribution, the primary objective was to enhance the crystallization behavior of poly(ethylene terephthalate) (PET). To accomplish this tack, three kinds of new nucleating agents SiO2-diethylene glycol-LMPET (PET-3), SiO2-triethylene glycol–LMPET(PET-4) and SiO2-tetraethylene glycol-LMPET (PET-5) nucleating agents were prepared via grafting different oligomers (diethylene glycol; triethylene glycol and tetraethylene glycol) to the surface of nano-SiO2 and then linking to the low molecular weight poly(ethylene terephthalate) (LMPET). These nano-particle nucleating agents facilitated the crystallization of PET. Differential scanning calorimetry (DSC) studies of the composites that pure PET blended with PET-3, PET-4 and PET-5 indicated that the longer ethoxy segment in the nucleating agents exhibited (i) higher degrees of crystallinity; (ii) faster rates of crystallization; and (iii) higher crystallization temperatures. The Jeziorny method was employed to analyze the non-isothermal crystallization kinetics of the composites. These works demonstrated that the PET-3, PET-4 and PET-5 were attractive nucleating agents for poly(ethylene terephthalate), and the longer the chain length of the ethoxy segment in the nucleating agents, the more efficient the nucleation effect. PMID:29641456

  7. Impact of polyethylene glycol 400/propylene glycol/hydroxypropyl-guar and 0.1% sodium hyaluronate on postoperative discomfort following cataract extraction surgery: a comparative study.

    PubMed

    Labiris, Georgios; Ntonti, Panagiota; Sideroudi, Haris; Kozobolis, Vassilios

    2017-01-01

    Universal postoperative guidelines for cataract extraction surgery are yet to be introduced. Artificial tears are gaining popularity as an additional integral component of the postoperative regime. The primary objective of this study was to explore the impact of two prevalent artificial tear preparations on postoperative discomfort following cataract extraction surgery. A total of 180 patients that underwent cataract extraction surgery were randomly divided into three groups according to their postoperative regime: a) Study group 1 (SG1) received a fixed combination of tobramycin and dexamethasone (FCTD) quid for 3 weeks and, additionally polyethylene glycol 400/propylene glycol/hydroxypropyl-guar quid, for 6 weeks, b) Study group 2 (SG2) received FCTD quid for 3 weeks and, additionally 0.1% sodium hyaluronate provided in the COMOD® device quid, for 6 weeks, and, c) Control Group (CG) received only FCTD quid for 3 weeks. The following indexes were evaluated at three postoperative checkpoints: 1) Subjective discomfort index (SDI) derived from four direct 10-scale Likert-type questions that were addressed to the patient and pertained to: a) foreign body sensation (FBS), b) blinking discomfort (BD), c) stinging sensation (SS), d) tearing sensation (TS), 2) Tear break-up time (TBUT), 3) Central corneal thickness (CCT) and, 4) Central Corneal Sensitivity (CCS). Both groups showed increased CCT values at the first examination point and reduced CCS values at all examination points. Furthermore, both SGs had better TBUT times at all examination points compared to CG (CG: 8.86 ± 1.08, SG1: 9.59 ± 1.45, CG2: 9.45 ± 1.33, p  < 0.05). BD was significantly better in both SGs only at the 1 st week of examination, while SDI values were better until the 3 rd week and only borderline better at 6 th week. Lastly, no significant differences were detected between SGs, regarding all parameters, at all examination points. Polyethylene glycol 400/propylene glycol/hydroxypropyl-guar and 0.1% sodium hyaluronate provided in the COMOD® device seem to be equally efficient in alleviating OSD symptoms following cataract extraction surgery and any of them should be routinely added to the postoperative regime. ClinicalTrials.gov Identifier: https://clinicaltrials.gov/ct2/show/NCT02558218NCT02558218.

  8. Self-assembly of core-polyethylene glycol-lipid shell (CPLS) nanoparticles and their potential as drug delivery vehicles.

    PubMed

    Shen, Zhiqiang; Loe, David T; Awino, Joseph K; Kröger, Martin; Rouge, Jessica L; Li, Ying

    2016-08-21

    Herein a new multifunctional formulation, referred to as a core-polyethylene glycol-lipid shell (CPLS) nanoparticle, has been proposed and studied in silico via large scale coarse-grained molecular dynamics simulations. A PEGylated core with surface tethered polyethylene glycol (PEG) chains is used as the starting configuration, where the free ends of the PEG chains are covalently bonded with lipid molecules (lipid heads). A complete lipid bilayer is formed at the surface of the PEGylated particle core upon addition of free lipids, driven by the hydrophobic properties of the lipid tails, leading to the formation of a CPLS nanoparticle. The self-assembly process is found to be sensitive to the grafting density and molecular weight of the tethered PEG chains, as well as the amount of free lipids added. At low grafting densities the assembly of CPLS nanoparticles cannot be accomplished. As demonstrated by simulations, a lipid bud/vesicle can be formed on the surface when an excess amount of free lipids is added at high grafting density. Therefore, the CPLS nanoparticles can only be formed under appropriate conditions of both PEG and free lipids. The CPLS nanoparticle has been recognized to be able to store a large quantity of water molecules, particularly with high molecular weight of PEG chains, indicating its capacity for carrying hydrophilic molecules such as therapeutic biomolecules or imaging agents. Under identical size and surface chemistry conditions of a liposome, it has been observed that the CPLS particle can be more efficiently wrapped by the lipid membrane, indicating its potential for a greater efficiency in delivering its hydrophilic cargo. As a proof-of-concept, the experimental realization of CPLS nanoparticles is explicitly demonstrated in this study. To test the capacity of the CPLS to store small molecule cargo a hydrophilic dye was successfully encapsulated in the particles' water soluble layer. The results of this study show the power and potential of simulation-driven approaches for guiding the design of more efficient nanomaterial delivery platforms.

  9. Molar Mass and Second Virial Coefficient of Polyethylene Glycol by Vapor Pressure Osmometry

    ERIC Educational Resources Information Center

    Schwinefus, Jeffrey J.; Checkal, Caleb; Saksa, Brian; Baka, Nadia; Modi, Kalpit; Rivera, Carlos

    2015-01-01

    In this laboratory experiment, students determine the number-average molar masses and second virial coefficients of polyethylene glycol (PEG) polymers ranging in molar mass from 200 to 1500 g mol[superscript -1] using vapor pressure osmometry (VPO). Students assess VPO in relation to accurate molar mass calculations of PEG polymers. Additionally,…

  10. Importance of poly(ethylene glycol) conformation for the synthesis of silver nanoparticles in aqueous solution

    USDA-ARS?s Scientific Manuscript database

    In the formation of silver nanoparticles (NPs) using silver nitrate in a poly(ethylene glycol) (PEG) aqueous solution, which acts as both a reducing and stabilizing agent, the PEG chain structure was found to play a significant role. Even though PEG 100 (100 kg/mol) has limited reducing sites of hyd...

  11. Intermolecular interactions at early stage of protein/detergent particle association induced by salt/polyethylene glycol mixtures.

    PubMed

    Odahara, Takayuki; Odahara, Koji

    2016-04-01

    Mixtures of neutral salts and polyethylene glycol are used for various purposes in biological studies. Although the effects of each component of the mixtures are theoretically well investigated, comprehension of their integrated effects remains insufficient. In this work, their roles and effects as a precipitant were clarified by studying dependence of precipitation curves on salt concentration for integral membrane protein/detergent particles of different physicochemical properties. The dependence of precipitation curves was reasonably related to intermolecular interactions among relevant molecules such as protein, detergent and polyethylene glycol by considering their physicochemical properties. The obtained relationships are useful as basic information to learn the early stage of biological macromolecular associations. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Ethylene glycol modified 2-(2‧-aminophenyl)benzothiazoles at the amino site: the excited-state N-H proton transfer reactions in aqueous solution, micelles and potential application in live-cell imaging

    NASA Astrophysics Data System (ADS)

    Liu, Bo-Qing; Chen, Yi-Ting; Chen, Yu-Wei; Chung, Kun-You; Tsai, Yi-Hsuan; Li, Yi-Jhen; Chao, Chi-Min; Liu, Kuan-Miao; Tseng, Huan-Wei; Chou, Pi-Tai

    2016-03-01

    Triethylene glycol monomethyl ether and poly(ethylene glycol) monomethyl ether modified 2-(2‧-aminophenyl)benzothiazoles, namely ABT-P3EG, ABT-P7EG and ABT-P12EG varied by different chain length of poly(ethylene glycol) at the amino site, were synthesized to probe their photophysical and bio-imaging properties. In polar, aprotic solvents such as CH2Cl2 ultrafast excited-state intramolecular proton transfer (ESIPT) takes place, resulting in a large Stokes shifted tautomer emission in the green-yellow (550 nm) region. In neutral water, ABT-P12EG forms micelles with diameters of 15  ±  3 nm under a critical micelle concentration (CMC) of ~80 μM, in which the tautomer emission is greatly enhanced free from water perturbation. Cytotoxicity experiments showed that all ABT-PnEGs have negligible cytotoxicity against HeLa cells even at doses as high as 1 mM. Live-cell imaging experiments were also performed, the results indicate that all ABT-PnEGs are able to enter HeLa cells. While the two-photon excitation emission of ABT-P3EG in cells cytoplasm shows concentration independence and is dominated by the anion blue fluorescence, ABT-P7EG and ABT-P12EG exhibit prominent green tautomer emission at  >  CMC and in part penetrate to the nuclei, adding an additional advantage for the cell imaging.

  13. Regulatory Control of Breast Tumor Cell Poly (ADP-Ribose) Polymerase

    DTIC Science & Technology

    2004-08-01

    polyethylene glycol precipitation, ion exchange chromatography, and density gradient sedimentation (Malkas et al., 1990; Applegren et al., 1995; Coll et...jtl of 25 mM NH4HCO 3/50% acetonitrile were added and the tubes were mixed for 35-40 min on a low setting using a microtube mixer. The pale blue...these isoforms. Proteins identified in these spots are shown in table 1: Spot #* Predominant Protein MCF-10A 1 Heat Shock Protein 90 cc (hsp-90 ct) 2

  14. Efficacy of polyethylene glycol 4000 on constipation of posttraumatic bedridden patients.

    PubMed

    Zhang, Lian-yang; Yao, Yuan-zhang; Wang, Tao; Fei, Jun; Shen, Yue; Chen, Yong-hua; Zong, Zhao-wen

    2010-06-01

    To investigate the efficacy and safety of polyethylene glycol 4000 on adult patients with functional constipation due to posttraumatic confinement to bed. A total of 201 posttraumatic bedridden patients were studied in this prospective, open-labeled, single-group study. Polyethylene glycol 4000 was administered orally for 14 days and the dosage was adjusted according to the Bristol stool types. Demographic characteristics, disease status, treatment period and factors affecting clinical outcome, especially the concomitant medications, were recorded. After administration of polyethylene glycol 4000, 194 cases (96.52%) showed remission of constipation, including 153 (76.12%) persistent remission. The average defecation frequency increased significantly after treatment and the percentage of patients with stools of normal types (Bristol types 3-5) increased as well. Genders, ages and concomitant medications showed no significant influence on the persistent remission rate. After consecutive treatment for two weeks, patients with slight movement showed a significantly higher remission rate than those without movement (95% vs 80%). At the end of treatment, most accompanying symptoms were relieved obviously. Patients with a medical history of constipation or ever taking laxatives showed a lower remission rate. Sixty cases (29.85%) developed diarrhea during the observational period, among whom 6 (10%) withdrew from the clinical observation voluntarily at the first onset of diarrhea. Two cases suffered from abdominal pain. Polyethylene glycol 4000 has efficacy on functional constipation in posttraumatic bedridden patients. Furthermore, patients with milder symptoms, more movement in bed, and longer duration of treatment but without accompanying symptoms can achieve a higher remission rate.

  15. Amperometric Biosensor Based on Zirconium Oxide/Polyethylene Glycol/Tyrosinase Composite Film for the Detection of Phenolic Compounds

    PubMed Central

    Ahmad, Nor Monica; Abdullah, Jaafar; Yusof, Nor Azah; Ab Rashid, Ahmad Hazri; Abd Rahman, Samsulida; Hasan, Md. Rakibul

    2016-01-01

    A phenolic biosensor based on a zirconium oxide/polyethylene glycol/tyrosinase composite film for the detection of phenolic compounds has been explored. The formation of the composite film was expected via electrostatic interaction between hexacetyltrimethylammonium bromide (CTAB), polyethylene glycol (PEG), and zirconium oxide nanoparticles casted on screen printed carbon electrode (SPCE). Herein, the electrode was treated by casting hexacetyltrimethylammonium bromide on SPCE to promote a positively charged surface. Later, zirconium oxide was mixed with polyethylene glycol and the mixture was dropped cast onto the positively charged SPCE/CTAB. Tyrosinase was further immobilized onto the modified SPCE. Characterization of the prepared nanocomposite film and the modified SPCE surface was investigated by scanning electron microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), and Cyclic voltamogram (CV). The developed biosensor exhibits rapid response for less than 10 s. Two linear calibration curves towards phenol in the concentrations ranges of 0.075–10 µM and 10–55 µM with the detection limit of 0.034 µM were obtained. The biosensor shows high sensitivity and good storage stability for at least 30 days. PMID:27367738

  16. Effect of reaction time and polyethylene glycol monooleate-isocyanate composition on the properties of polyurethane-polysiloxane modified epoxy

    NASA Astrophysics Data System (ADS)

    Triwulandari, Evi; Ramadhan, Mohammad Kemilau; Ghozali, Muhammad

    2017-11-01

    Polyurethane-polysiloxane modified epoxy based on polyethylene glycol monooleate (PSME-PEGMO) was synthesized. Polyethylene glycol monooleate (PEGMO) for the synthesis of PSME-GMO was synthesized via esterification between oleic acid and polyethylene glycol by using sodium hydroxide as catalyst. Synthesis of PSME-PEGMO was conducted by reacting epoxy, isocyanate, PEGMO, and polysiloxane (hydrolyzed and condensable 3-glycidyloxypropyltrimethoxysilane) simultaneously in one step. This synthesis was carried out by varied the reaction time (1, 2, 3 hours), PEGMO-isocyanate composition (PI composition: 10 and 20 % toward epoxy), and isocyanate/PEGMO ratio (NCO/OH ratio: 1.5 and 2.5). Characterization of PSME-PEGMO was conducted by determining the isocyanate conversion, viscosity analysis, mechanical properties (tensile strength and elongation at break) and thermal analysis using thermogravimetric analysis (TGA). The data show that the PI composition and NCO/OH ratio does not affect the isocyanate conversion linearly. The viscosity of PSME-PEGMO product at ratio and composition variation show has tended to increase with increasing of reaction time. The highest tensile strength and elongation at break PSME-PEGMO was shown by PI composition 20%, NCO/OH ratio 2.5 and reaction time 3 hours.

  17. Self-assembly of core-polyethylene glycol-lipid shell (CPLS) nanoparticles and their potential as drug delivery vehicles

    NASA Astrophysics Data System (ADS)

    Shen, Zhiqiang; Loe, David T.; Awino, Joseph K.; Kröger, Martin; Rouge, Jessica L.; Li, Ying

    2016-08-01

    Herein a new multifunctional formulation, referred to as a core-polyethylene glycol-lipid shell (CPLS) nanoparticle, has been proposed and studied in silico via large scale coarse-grained molecular dynamics simulations. A PEGylated core with surface tethered polyethylene glycol (PEG) chains is used as the starting configuration, where the free ends of the PEG chains are covalently bonded with lipid molecules (lipid heads). A complete lipid bilayer is formed at the surface of the PEGylated particle core upon addition of free lipids, driven by the hydrophobic properties of the lipid tails, leading to the formation of a CPLS nanoparticle. The self-assembly process is found to be sensitive to the grafting density and molecular weight of the tethered PEG chains, as well as the amount of free lipids added. At low grafting densities the assembly of CPLS nanoparticles cannot be accomplished. As demonstrated by simulations, a lipid bud/vesicle can be formed on the surface when an excess amount of free lipids is added at high grafting density. Therefore, the CPLS nanoparticles can only be formed under appropriate conditions of both PEG and free lipids. The CPLS nanoparticle has been recognized to be able to store a large quantity of water molecules, particularly with high molecular weight of PEG chains, indicating its capacity for carrying hydrophilic molecules such as therapeutic biomolecules or imaging agents. Under identical size and surface chemistry conditions of a liposome, it has been observed that the CPLS particle can be more efficiently wrapped by the lipid membrane, indicating its potential for a greater efficiency in delivering its hydrophilic cargo. As a proof-of-concept, the experimental realization of CPLS nanoparticles is explicitly demonstrated in this study. To test the capacity of the CPLS to store small molecule cargo a hydrophilic dye was successfully encapsulated in the particles' water soluble layer. The results of this study show the power and potential of simulation-driven approaches for guiding the design of more efficient nanomaterial delivery platforms.Herein a new multifunctional formulation, referred to as a core-polyethylene glycol-lipid shell (CPLS) nanoparticle, has been proposed and studied in silico via large scale coarse-grained molecular dynamics simulations. A PEGylated core with surface tethered polyethylene glycol (PEG) chains is used as the starting configuration, where the free ends of the PEG chains are covalently bonded with lipid molecules (lipid heads). A complete lipid bilayer is formed at the surface of the PEGylated particle core upon addition of free lipids, driven by the hydrophobic properties of the lipid tails, leading to the formation of a CPLS nanoparticle. The self-assembly process is found to be sensitive to the grafting density and molecular weight of the tethered PEG chains, as well as the amount of free lipids added. At low grafting densities the assembly of CPLS nanoparticles cannot be accomplished. As demonstrated by simulations, a lipid bud/vesicle can be formed on the surface when an excess amount of free lipids is added at high grafting density. Therefore, the CPLS nanoparticles can only be formed under appropriate conditions of both PEG and free lipids. The CPLS nanoparticle has been recognized to be able to store a large quantity of water molecules, particularly with high molecular weight of PEG chains, indicating its capacity for carrying hydrophilic molecules such as therapeutic biomolecules or imaging agents. Under identical size and surface chemistry conditions of a liposome, it has been observed that the CPLS particle can be more efficiently wrapped by the lipid membrane, indicating its potential for a greater efficiency in delivering its hydrophilic cargo. As a proof-of-concept, the experimental realization of CPLS nanoparticles is explicitly demonstrated in this study. To test the capacity of the CPLS to store small molecule cargo a hydrophilic dye was successfully encapsulated in the particles' water soluble layer. The results of this study show the power and potential of simulation-driven approaches for guiding the design of more efficient nanomaterial delivery platforms. Electronic supplementary information (ESI) available: Simulation protocol, simulation results for the self-assembly of CPLS nanoparticles, membrane wrapping and free energy change of grafted PEG polymers. See DOI: 10.1039/C6NR04134E

  18. Biomaterials for Improved Wound Healing

    DTIC Science & Technology

    2013-10-01

    is silver sulphadiazine (SSD) [6-7]. SSD possesses a broad spectrum of activity against gram- positive and gram-negative bacteria as well as fungi [8... polyethylene glycol-based fibrin gel (PEGylated fibrin gel) induces vasculogenesis both in vitro and in vivo [20]. To exploit the inherent ability of fibrin as...Loaded Chitosan Microspheres Impregnated in Polyethylene Glycol Fibrin Gels (SSD-CSM-PEGylated fibrin gels) and Adipose Derived Stem Cells embedded

  19. Control of osmotic pressure of culture solutions with polyethylene glycol.

    PubMed

    LAGERWERFF, J V; OGATA, G; EAGLE, H E

    1961-05-12

    Experiments with kidney beans indicate that Carbowax polyethylene glycol, molecular weight 20,000, upon purification, may be used as an agent to control the osmotic pressure of plant nutrient solutions without the hazard of interference with normal metabolic processes. With the sodium electrode and the thermocouple psychrometer, interaction between ions and Carbowax is shown to lead to a slight dissociation of the latter.

  20. [Spleen, liver and kidney-strengthening formula combined with polyethylene glycol interferon in treatment of chronic hepatitis B].

    PubMed

    Chen, Wei

    2016-02-01

    To observe the clinical efficacy of spleen, liver and kidney-strengthening formula combined with polyethylene glycol interferon in the treatment of HBeAg positive chronic hepatitis B(HP-HBV).One hundred and twenty-six patients with HP-HBV, who were treated in the hospital from June 2012 to December 2014, were selected and injected with polyethylene glycol interferon α-2a(or α-2b). The treatment course for the patients lasted for 24 weeks. Base on the level of HBV-DNA, patients are divided into response group and poor response group. According to random number table, the poor response group were randomized into control group and test group. Patients in the control group were injected with polyethylene glycol interferon α-2a(or α-2b), and patients in the test group were treated with spleen, liver and kidney-strengthening formula combined with polyethylene glycol interferon. Clinical efficacies of the 2 groups were observed, and changes in the level of HBeAg, ALT and HBV-DNA were observed before treatment and at the 24th week after treatment, and virological and serological response, biochemical responses, integral clinical symptoms and signs, adverse reactions were observed after 48 weeks of treatment.After 24 weeks of treatment, the response group was significantly better than the poor response group in HBeAg, ALT and the level of HBV-DNA(P<0.05). After 48 weeks of treatment, there was statistical significance in HBV-DNA negative conversion rate, HBeAg negative conversion rate between the 2 groups(P<0.05), and the test group was better in the two indicators. And the test group was significantly lower than the control group in clinical symptoms and signs score at the 48th week after treatment(P<0.05), with a significantly lower adverse reaction rate than the control group(P<0.05).Combination of spleen, liver and kidney-strengthening formula and polyethylene glycol interferon α-2a was effective and safe in the treatment of chronic hepatitis B, and so worth promoting in clinic. Copyright© by the Chinese Pharmaceutical Association.

  1. Development of Polyethylene Glycol and Hard Fat-Based Mucoadhesive Tablets Containing Various Types of Polyvinyl Alcohols as Mucoadhesive Polymers for Buccal Application.

    PubMed

    Ikeuchi-Takahashi, Yuri; Kobayashi, Ayaka; Onishi, Hiraku

    2017-06-01

    Topical drug application has the advantage of avoiding systemic side effects. We attempted to develop a long-acting matrix-type tablet containing indomethacin (IM) with low physical stimulus and potent mucoadhesive force to treat pain caused by oral aphtha. A mixture of polyethylene glycol (PEG) and hard fat was used as the tablet base. Ethylcellulose was added to the base in an attempt to control drug release. Tablets with PEG as a base were also prepared for comparison. Polyvinyl alcohols (PVAs) with various degrees of saponification were added to increase the mucoadhesive force. From the optical microscopic observations, formulations using PEG and hard fat exhibit PEG/hard fat dispersions caused by the stabilizing effects of PVA. Although the tablets using PEG and hard fat showed sufficient adhesiveness and sustained drug release, those using PEG as the base did not. Drug release was controlled by the amount of hard fat and the saponification degree of PVA. The drug release rate was most increased in a tablet containing PVA with an intermediate degree of saponification, PEG and hard fat. From differential scanning calorimetry and powder X-ray diffraction, IM was considered to exist in the molecular phase. From the results of buccal administration of tablets to rats, highest tissue concentrations were observed in the tablet containing PVA with the intermediate degree of saponification using PEG and hard fat, and the plasma concentrations were sufficiently low in comparison.

  2. Optimization of Polysulfone / Graphene Oxide / Polyethylene Glycol / Triaminopyrimidine by Using Response Surface Methodology

    NASA Astrophysics Data System (ADS)

    Riduan Jamalludin, Mohd; Harun, Zawati; Khadijah Hubadillah, Siti; Hafiz Dzarfan Othman, Mohd; Hasliza Kamarudin, Noor; Zaini Yunos, Muhamad; Izzati Ismail, Ras; Lailina, N. M.

    2018-03-01

    The addition of polyethylene glycol (PEG), graphene oxide (GO) and triaminopyrimidine (TAP) into polysulfone membranes was used to modify the membrane morphology and increase membrane performance. The central composite design of the response surface methodology was used to predict the maximum permeability and rejection of the PSf membrane. The parameter chosen for this study were PEG (7-14 wt%), GO (0-2.5wt%) and TAP (0-0.5 wt%) concentration. The flat sheet membrane was prepared via phase inversion technique where polysulfone (PSf) was used as base polymer. Various concentration of GO, PEG and TAP were added into the casting solution to produce different membrane composition. PEG was added as pore forming agent for the PSf membrane while inorganic additive such as GO was used to increase the hydrophilicity of the membrane. Besides that, the addition of TAP as a compatibilizer to enhance the physical interaction between GO and PEG. The characterization and surface morphology of produced membrane were analysed via scanning electron microscope, SEM and X-ray diffraction, XRD. The optimization of membrane performance was carried out by using response surface methodology (RSM). The performance of the membrane was analysed by using distilled water for pure water flux test and humic acid for rejection test. The optimized responses, membrane permeability and rejection obtained experimentally were 301.562 Lm-2h-1 and 91.562% respectively, with deviation from the predicted value of 7.884 and 0.4381 %, respectively.

  3. Laccase-catalyzed removal of 2,4-dimethylphenol from synthetic wastewater: effect of polyethylene glycol and dissolved oxygen.

    PubMed

    Ghosh, J P; Taylor, K E; Bewtra, J K; Biswas, N

    2008-04-01

    The potential use of laccase (SP-504) in an advanced oxidation-based treatment technology to remove 2,4-dimethylphenol (DMP) from water was investigated with and without the additive, polyethylene glycol (PEG). The DMP concentration was varied between 1.0 and 5.0 mM. The optimization of pH and enzyme concentration in the presence and absence of PEG was carried out. All experiments were carried out in continuously stirred reactors for 3h at room temperature. The reaction was initiated by adding enzyme to the reaction mixture. For more than 95% removal of DMP, the presence of PEG reduced the inactivation of enzyme so that the required enzyme concentrations were reduced by about 2-fold compared to the same reactions in the absence of PEG. Finally, the PEG concentrations were optimized to obtain the minimum dose required. For higher substrate concentrations, the availability of oxygen was insufficient in achieving 95% or more removal. Therefore, the effect of increasing dissolved oxygen at higher substrate concentration was investigated. The laccase studied was capable of efficiently removing DMP at very low enzyme concentrations and hence shows great potential for cost-effective industrial applications.

  4. Amphiphilic polymeric micelles as the nanocarrier for peroral delivery of poorly soluble anticancer drugs.

    PubMed

    Tian, Ye; Mao, Shirui

    2012-06-01

    Many amphiphilic copolymers have recently been synthesized as novel promising micellar carriers for the delivery of poorly water-soluble anticancer drugs. Studies on the formulation and oral delivery of such micelles have demonstrated their efficacy in enhancing drug uptake and absorption, and exhibit prolonged circulation time in vitro and in vivo. In this review, literature on hydrophobic modifications of several hydrophilic polymers, including polyethylene glycol, chitosan, hyaluronic acid, pluronic and tocopheryl polyethylene glycol succinate, is summarized. Parameters influencing the properties of polymeric micelles for oral chemotherapy are discussed and strategies to overcome main barriers for polymeric micelles peroral absorption are proposed. During the design of polymeric micelles for peroral chemotherapy, selecting or synthesizing copolymers with good compatibility with the drug is an effective strategy to increase drug loading and encapsulation efficiency. Stability of the micelles can be improved in different ways. It is recommended to take permeability, mucoadhesion, sustained release, and P-glycoprotein inhibition into consideration during copolymer preparation or to consider adding some excipients in the formulation. Furthermore, both the copolymer structure and drug loading methods should be controlled in order to get micelles with appropriate particle size for better absorption.

  5. Y2O3:Eu phosphor particles prepared by spray pyrolysis from a solution containing citric acid and polyethylene glycol

    NASA Astrophysics Data System (ADS)

    Roh, H. S.; Kang, Y. C.; Park, H. D.; Park, S. B.

    Y2O3:Eu phosphor particles were prepared by large-scale spray pyrolysis. The morphological control of Y2O3:Eu particles in spray pyrolysis was attempted by adding polymeric precursors to the spray solution. The effect of composition and amount of polymeric precursors on the morphology, crystallinity and photoluminescence characteristics of Y2O3:Eu particles was investigated. Particles prepared from a solution containing polyethylene glycol (PEG) with an average molecular weight of 200 had a hollow structure, while those prepared from solutions containing adequate amounts of citric acid (CA) and PEG had a spherical shape, filled morphology and clean surfaces after post-treatment at high temperature. Y2O3:Eu particles prepared from an aqueous solution with no polymeric precursors had a hollow structure and rough surfaces after post-treatment. The phosphor particles prepared from solutions with inadequate amounts of CA and/or PEG also had hollow and/or fragmented structures. The particles prepared from the solution containing 0.3 M CA and 0.3 M PEG had the highest photoluminescence emission intensity, which was 56% higher than that of the particles prepared from aqueous solution without polymeric precursors.

  6. Distribution of free and antibody-bound peptide hormones in two-phase aqueous polymer systems

    PubMed Central

    Desbuquois, Bernard; Aurbach, G. D.

    1972-01-01

    Peptide hormones labelled with radioactive iodine were partitioned into the aqueous two-phase polymer systems developed by Albertsson (1960) and the conditions required for separation of free from antibody-bound hormone have been worked out. Hormones studied included insulin, growth hormone, parathyroid hormone and [arginine]-vasopressin. Free and antibody-bound hormones show different distribution coefficients in a number of systems tested; two systems, the dextran–polyethylene glycol and dextran sulphate–polyethylene glycol system, give optimum separation. Free hormones distribute readily into the upper phase of these systems, whereas hormone–antibody complexes, as well as uncombined antibody, are found almost completely in the lower phase. Various factors including the polymer concentration, the ionic composition of the system, the nature of the hormone and the nature of added serum protein differentially affect the distribution coefficients for free and antibody-bound hormone. These factors can be adequately controlled so as to improve separation. The two-phase partition method has been successfully applied to measure binding of labelled hormone to antibody under standard radioimmunoassay conditions. It exhibits several advantages over the method of equilibration dialysis and can be applied to the study of non-immunological interactions. PMID:4672674

  7. Effects of gum chewing on abdominal discomfort, nausea, vomiting and intake adherence to polyethylene glycol solution of patients in colonoscopy preparation.

    PubMed

    Lee, Jisun; Lee, Eunjin; Kim, Yumi; Kim, Eun; Lee, Yaera

    2016-02-01

    This study aimed to reduce the common discomfort of colonoscopy patients when taking a bowel cleansing solution. Gum chewing, a form of sham feeding, was examined as a possible efficient intervention to reduce the discomfort from consuming polyethylene glycol. Sham feeding is a method that is similar to food intake, which stimulates the cephalic-vagal reflex, promotes secretion of gastrointestinal hormones, and stimulates movement of the gastrointestinal tract. Sham feeding with chewing gum has been shown to promote bowel motility. This was an experimental study utilising a randomised control group post-test design. This study was conducted in Seoul, Korea from August-October 2012. Patients were randomly allocated into two groups; a gum-chewing group (n = 66) or a control group (n = 65). In the control group, patients drank a polyethylene glycol solution according to the general protocol. For the gum-chewing group, patients had to chew one stick of sugarless gum during the pause interval of drinking the polyethylene glycol solution. Results were analysed using the Mann-Whitney U-test, t-test, Chi-square test or Fisher's exact test. The gum-chewing group reported significantly lower abdominal discomfort, nausea and vomiting and took a shorter time to ingest the polyethylene glycol solution than the control group. Gum chewing is efficient in improving abdominal discomfort, nausea, vomiting and the intake adherence of patients in colonoscopy preparation. Gum chewing was demonstrated by this study to be a potentially effective nursing intervention that is easy for patients to perform with simple instructions and is low cost with no side effects. © 2016 John Wiley & Sons Ltd.

  8. Supported polyethylene glycol stabilized platinum nanoparticles for chemoselective hydrogenation of halonitrobenzenes in scCO2.

    PubMed

    Cheng, Haiyang; Meng, Xiangchun; He, Limin; Lin, Weiwei; Zhao, Fengyu

    2014-02-01

    Polyethylene glycol stabilized platinum nanoparticles were immobilized on solid supports such as γ-Al2O3, SBA-15, TiO2 and active carbon, forming supported polyethylene glycol stabilized platinum nanoparticles (SPPNs). In the hydrogenation of p-chloronitrobenzene (p-CNB) in supercritical carbon dioxide (scCO2), the SPPN showed high selectivity to p-chloroaniline (>99.3%) in the whole range of conversion. Such high selectivity to corresponding haloanilines (HANs) (>99.1%) was also obtained in the hydrogenation of o-CNB, m-CNB, 2-chloro-6-nitrotoluene, p-bromonitrobenzene and m-iodonitrobenzene. The dehalogenation and the accumulation of intermediates were fully inhibited simultaneously in scCO2. The SPPN catalysts could be reused several times without loss of high selectivity in present reaction system. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Process for separating and recovering an anionic dye from an aqueous solution

    DOEpatents

    Rogers, Robin; Horwitz, E. Philip; Bond, Andrew H.

    1998-01-01

    A solid/liquid phase process for the separation and recovery of an anionic dye from an aqueous solution is disclosed. The solid phase comprises separation particles having surface-bonded poly(ethylene glycol) groups, whereas the aqueous solution from which the anionic dye molecules are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved lyotropic salt. After contact between the aqueous solution and separation particles, the anionic dye is bound to the particles. The bound anionic dye molecules are freed from the separation particles by contacting the anionic dye-bound particles with an aqueous solution that does not contain a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved lyotropic salt to form an aqueous anionic dye solution whose anionic dye concentration is preferably higher than that of the initial dye-containing solution.

  10. Solid-phase microfibers based on polyethylene glycol modified single-walled carbon nanotubes for the determination of chlorinated organic carriers in textiles.

    PubMed

    Zhang, Wei-Ya; Sun, Yin; Wang, Cheng-Ming; Wu, Cai-Ying

    2011-09-01

    Based on polyethylene glycol modified single-walled carbon nanotubes, a novel sol-gel fiber coating was prepared and applied to the headspace microextraction of chlorinated organic carriers (COCs) in textiles by gas chromatography-electron capture detection. The preparation of polyethylene glycol modified single-walled carbon nanotubes and the sol-gel fiber coating process was stated and confirmed by infrared spectra, Raman spectroscopy, and scanning electron microscopy. Several parameters affecting headspace microextraction, including extraction temperature, extraction time, salting-out effect, and desorption time, were optimized by detecting 11 COCs in simulative sweat samples. Compared with the commercial solid-phase microextraction fibers, the sol-gel polyethylene glycol modified single-walled carbon nanotubes fiber showed higher extraction efficiency, better thermal stability, and longer life span. The method detection limits for COCs were in the range from 0.02 to 7.5 ng L(-1) (S/N = 3). The linearity of the developed method varied from 0.001 to 50 μg L(-1) for all analytes, with coefficients of correlation greater than 0.974. The developed method was successfully applied to the analysis of trace COCs in textiles, the recoveries of the analytes indicated that the developed method was considerably useful for the determination of COCs in ecological textile samples.

  11. Conformational effects on cationization of poly(ethylene glycol) by alkali metal ions in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

    NASA Astrophysics Data System (ADS)

    Shimada, Kayori; Matsuyama, Shigetomo; Saito, Takeshi; Kinugasa, Shinichi; Nagahata, Ritsuko; Kawabata, Shin-Ichirou

    2005-12-01

    Conformational effects of polymer chains on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) were studied by using an equimolar mixture of uniform poly(ethylene glycol)s (PEGs) and by molecular dynamics simulations. Uniform PEGs with degrees of polymerization n = 8-39 were separated from commercial PEG samples by preparative supercritical fluid chromatography. MALDI-TOFMS spectra of an equimolar mixture of the uniform PEGs in aqueous ethanol were measured by adding a mixture of 2,5-dihydroxybenzoic acid (as a matrix reagent) and five alkali metal chlorides (LiCl, NaCl, KCl, RbCl, and CsCl). After optimization of the matrix concentration and laser power, five types of adduct cationized by Li+, Na+, K+, Rb+, and Cs+ could be identified simultaneously in the same spectrum. In the lower molecular-mass region around 103, the spectral intensity increase rapidly with increasing molecular mass of PEG; this rapid increase in the spectral intensity started at a lower molecular mass for smaller adduct cations. Molecular dynamics simulations were used to calculated the affinity of PEG for the adduct cations. These experimental and simulated results showed that the observed spectral intensities in MALDI-TOFMS were markedly affected by the species of adduct cations and the degree of polymerization of the PEG, and that they were dependent on the stability of the PEG-cation complex.

  12. Stability Conditions and Mechanism of Cream Soaps: Effect of Polyols.

    PubMed

    Sagitani, Hiromichi; Komoriya, Masumi

    2015-01-01

    Fatty acids, fatty acid potassium soaps, polyols and water are essential ingredients for producing stable cream soaps. The solution behavior of the above four components system has been studied to elucidate the effect of four sorts of polyols (glycerol, 1,3-butylene glycol, polyethylene glycol 400 and dipropylene glycol) on the stability of cream soaps. It has been revealed that the lamellar liquid crystalline one-phase converted to a two-phase of a lamellar phase and an isotropic aqueous solution by the addition of a few percent of 1,3-butylene glycol, polyethylene glycol 400 and dipropylene glycol, whereas the lamellar one-phase was remained by about 50 wt% of glycerol in the aqueous solution. The X-ray data at room temperature showed that the existence of 1:1 acid soap (1:1 mole ratio of potassium soap/fatty acid) crystals in the 1,3-butylene glycol, polyethylene glycol 400 and dipropylene glycol systems, whereas that the coexistence of 1:1 acid soap crystal and a lamellar gel phase (swelled lamellar gel structure) in the glycerol system. The phase transition peaks from coagel to gel (Tgel) and from gel to liquid state (Tc) were appeared in the above four polyol systems by DSC measurements. It was confirmed from the combined data of SAXS and DSC that the existence of anhydrous 1:1 acid soap gels (or with small amount of bound water) in the all polyol systems, whereas the coexistence of the anhydrate gel and the swelled gel with a lot of intermediate water in the only glycerol system. This swelled gel structure would be contributed to stabilize the dispersed anhydrate acid soap crystals in cream soaps.

  13. The effect of polymer composition on the gelation behavior of PLGA-g-PEG biodegradable thermoreversible gels.

    PubMed

    Tarasevich, B J; Gutowska, A; Li, X S; Jeong, B-M

    2009-04-01

    Graft copolymers consisting of a poly(D,L-lactic acid-co-glycolic acid) backbone grafted with polyethylene glycol side chains were synthesized and formed thermoreversible gels in aqueous solutions that exhibited solution behavior at low temperature and sol-to-gel transitions at higher temperature. The composition of the polymer and relative amounts of polylactic acid, glycolic acid, and ethylene glycol were varied by controlling the precursor concentrations and reaction temperature. The gelation temperature could be systematically tailored from 15 to 34 degrees C by increasing the concentration of polyethylene glycol in the graft copolymer. The gelation temperature also depended on the polymer molecular weight and concentration. This work has importance for the development of water soluble gels with tailored compositions and gelation temperatures for use in tissue engineering and as injectable depots for drug delivery. Copyright 2008 Wiley Periodicals, Inc.

  14. A thermosensitive hydrogel based on biodegradable amphiphilic poly(ethylene glycol) polycaprolactone poly(ethylene glycol) block copolymers

    NASA Astrophysics Data System (ADS)

    Gong, Chang Yang; Qian, Zhi Yong; Liu, Cai Bing; Juan Huang, Mei; Gu, Ying Chun; Wen, Yan Jun; Kan, Bing; Wang, Ke; Dai, Mei; Li, Xing Yi; Gou, Ma Ling; Tu, Ming Jing; Wei, Yu Quan

    2007-06-01

    A series of low molecular weight poly(ethylene glycol)-polycaprolactone-poly(ethylene glycol) (PEG-PCL-PEG) biodegradable block copolymers were successfully synthesized using isophorone diisocyanate (IPDI) as the coupling agent, and were characterized using 1H NMR and Fourier transform infrared spectroscopy. The aqueous solutions of the PEG-PCL-PEG copolymers displayed a special thermosensitive gel-sol transition when the concentration was above the corresponding critical gel concentration. Gel-sol phase diagrams were recorded using the test-tube-inversion method; they depended on the hydrophilic/hydrophobic balance in the macromolecular structure, as well as some other factors, including the heating history, volume, and the ageing time of the copolymer aqueous solutions and dissolution temperature of the copolymers. As a result, the gel-sol transition temperature range could be altered, which might be very useful for application in injectable drug delivery systems. This work was financially supported by the Chinese Key Basic Research Program (2004CB518800 and 2004CB518807), and the Sichuan Key Project of Science and Technology (06(05SG022-021-02)).

  15. Process for separating and recovering an anionic dye from an aqueous solution

    DOEpatents

    Rogers, R.; Horwitz, E.P.; Bond, A.H.

    1998-01-13

    A solid/liquid phase process for the separation and recovery of an anionic dye from an aqueous solution is disclosed. The solid phase comprises separation particles having surface-bonded poly(ethylene glycol) groups, whereas the aqueous solution from which the anionic dye molecules are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved lyotropic salt. After contact between the aqueous solution and separation particles, the anionic dye is bound to the particles. The bound anionic dye molecules are freed from the separation particles by contacting the anionic dye-bound particles with an aqueous solution that does not contain a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved lyotropic salt to form an aqueous anionic dye solution whose anionic dye concentration is preferably higher than that of the initial dye-containing solution. 7 figs.

  16. Effect of polyethylene glycol 4000 supplementation on the performance of indigenous Pedi goats fed different levels of Acacia nilotica leaf meal and ad libitum Buffalo grass hay.

    PubMed

    Motubatse, M R; Ng'ambi, J W; Norris, D; Malatje, M M

    2008-04-01

    In a first of two experiments, twenty yearling male Pedi goats weighing 21.3 +/- 0.5 kg live weight were used in a 37-day study in a 2 (levels of PEG 4000) x 2 (levels ofAcacia) Factorial arrangement in a Completely Randomised Design to determine the effect of the level of Acacia nilotica leaf meal supplementation plus 23 g polyethylene glycol 4000 on diet intake and digestibility, and growth rate of Pedi goats fed ad libitum Buffalo grass hay. Acacia nilotica leaf meal contained high amounts of total phenolics (2.04% DM) and low amounts of condensed tannins; both extracted (0.37% DM) and unextracted (1.83% DM). Supplementation with PEG 4000 increased (P < 0.05) crude protein intake as the level of Acacia nilotica leaf meal increased from 80 to 120 g. Similarly, treatment with PEG 4000 improved (P < 0.05) DM, OM and CP digestibilities when compared to 80 g Acacia nilotica leaf meal. Supplementation with PEG 4000 resulted in an increase (P < 0.05) in blood urea concentrations. Polyethylene glycol 4000 has the potential to improve the feeding value of A. nilotica leaf meal and can, therefore, be used in the feeding systems for ruminant animals. The second experiment determined the effect of A. nilotica leaf meal supplementation on in vitro digestibility of the diets similar to the actual ratios of the first experiment. Level of A. nilotica leaf meal supplementation plus 23 g PEG 4000 supplementation improved (P < 0.05) in vitro DM, OM and CP digestibilities where 120 g A. nilotica leaf meal was supplemented. Similarly, 23 g PEG 4000 supplementation also improved (P < 0.05) in vitro CP digestibility where 80 g A. nilotica leaf meal was supplemented. In vivo DM and OM digestibilities were best predicted from in vitro DM and OM digestibilities while in vivo CP was explained by in vitro OM and CP digestibilities. It is, therefore, concluded that in vitro DM and OM digestibilities have good capacity to predict in vivo DM and OM digestibilities while OM and CP digestibilities have good capacity to predict in vivo CP digestibility.

  17. Biocompatibility of modified ultra-high-molecular-weight polyethylene

    NASA Astrophysics Data System (ADS)

    Novotná, Z.; Lacmanová, V.; Rimpelová, S.; Juřik, P.; Polívková, M.; Å vorčik, V.

    2016-09-01

    Ultra-high-molecular-weight polyethylene (UHMWPE, PE) is a synthetic polymer used for biomedical applications because of its high impact resistance, ductility and stability in contact with physiological fluids. Therefore this material is being used in human orthopedic implants such as total joint replacements. Surface modification of this material relates to changes of its surface hydrophilicity, energy, microstructure, roughness, and morphology, all influencing its biological response. In our recent work, PE was treated by an Ar+ plasma discharge and then grafted with biologically active polyethylene glycol in order to enhance adhesion and proliferation of mouse fibroblast (L929). The surface properties of pristine PE and its grafted counterparts were studied by goniometry (surface wettability). Furthermore, Atomic Force Microscopy was used to determine the surface morphology and roughness. The biological response of the L929 cell lines seeded on untreated and plasma treated PE matrices was quantified in terms of the cell adhesion, density, and metabolic activity. Plasma treatment leads to the ablation of the polymer surface layers. Plasma treatment and subsequent poly(ethylene glycol) grafting lead to dramatic changes in the polymer surface morphology and roughness. Biological tests, performed in vitro, show increased adhesion and proliferation of cells on modified polymers. Grafting with poly(ethylene glycol) increases cell proliferation compared to plasma treatment.

  18. Development of Magnetic Nanovectors for Treatment and Imaging of Breast Cancer Metastasis to the Brain

    DTIC Science & Technology

    2014-10-01

    polyethylene glycol (PEG)-grafted chitosan (C)-polyethyleneimine (P), or CP. The tumor targeting peptide, chlorotoxin (CTX), and siRNA (designed to...NP) core and a shell comprised of a copolymer of polyethylene glycol (PEG)-grafted chitosan (C)-polyethyleneimine (PEI), or C-PEG-PEI. The tumor...be upregulated in breast cancer cells and is a key mediator of cell metastasis (6). In this naovector system, the combination of chitosan and PEG

  19. [Study on rhG-CSF modified with polyethylene glycol].

    PubMed

    Zhang, Lin-Lin; Zheng, Chun-Yang; Lei, Jian-Du; Ma, Guang-Hui; Su, Zhi-Guo; Wang, Li

    2005-11-01

    Monomethoxy Polyethylene Glycol(mPEG20000) was activated by N-hydroxysuccinimede and analyzed by infrared spectrum and hydrolysis kinetics. In order to propose the optimized reaction conditions of mono-PEGylated rhG-CSF, orthogonal design of the experiment was investigated. Ion exchange chromatography was used to separate and purify PEGylated rhG-CSF from unPEGylated rhG-CSF. The purity of mono-PEGylated rhG-CSF was analyzed by high performance liquid chromatography (HPLC) to be 97%.

  20. Selective targeting of melanoma by PEG-masked protein-based multifunctional nanoparticles

    PubMed Central

    Vannucci, Luca; Falvo, Elisabetta; Fornara, Manuela; Di Micco, Patrizio; Benada, Oldrich; Krizan, Jiri; Svoboda, Jan; Hulikova-Capkova, Katarina; Morea, Veronica; Boffi, Alberto; Ceci, Pierpaolo

    2012-01-01

    Background Nanoparticle-based systems are promising for the development of imaging and therapeutic agents. The main advantage of nanoparticles over traditional systems lies in the possibility of loading multiple functionalities onto a single molecule, which are useful for therapeutic and/or diagnostic purposes. These functionalities include targeting moieties which are able to recognize receptors overexpressed by specific cells and tissues. However, targeted delivery of nanoparticles requires an accurate system design. We present here a rationally designed, genetically engineered, and chemically modified protein-based nanoplatform for cell/tissue-specific targeting. Methods Our nanoparticle constructs were based on the heavy chain of the human protein ferritin (HFt), a highly symmetrical assembly of 24 subunits enclosing a hollow cavity. HFt-based nanoparticles were produced using both genetic engineering and chemical functionalization methods to impart several functionalities, ie, the α-melanocyte-stimulating hormone peptide as a melanoma-targeting moiety, stabilizing and HFt-masking polyethylene glycol molecules, rhodamine fluorophores, and magnetic resonance imaging agents. The constructs produced were extensively characterized by a number of physicochemical techniques, and assayed for selective melanoma-targeting in vitro and in vivo. Results Our HFt-based nanoparticle constructs functionalized with the α-melanocyte-stimulating hormone peptide moiety and polyethylene glycol molecules were specifically taken up by melanoma cells but not by other cancer cell types in vitro. Moreover, experiments in melanoma-bearing mice indicate that these constructs have an excellent tumor-targeting profile and a long circulation time in vivo. Conclusion By masking human HFt with polyethylene glycol and targeting it with an α-melanocyte-stimulating hormone peptide, we developed an HFt-based melanoma-targeting nanoplatform for application in melanoma diagnosis and treatment. These results could be of general interest, because the same strategy can be exploited to develop ad hoc nanoplatforms for specific delivery towards any cell/tissue type for which a suitable targeting moiety is available. PMID:22619508

  1. THE STIMULATING EFFECT OF GLYCOLS AND THEIR POLYMERS ON THE TARSAL RECEPTORS OF BLOWFLIES

    PubMed Central

    Dethier, V. G.; Chadwick, L. E.

    1948-01-01

    The rejection thresholds of Phormia regina Meigen for twenty-four glycols have been determined. A definite relationship between the concentration of the test material and the distribution of thresholds has been noted regularly in samples of flies selected at random from a population of known age which had been reared under standard conditions. The scattering of thresholds is normal with respect to the logarithm of concentration. Recalculation of the data of other workers reveals the same sort of relationship with other species of insects and the minnow Phoxinus. The underlying reason for the phenomenon is not known. The glycols in common with other series of homologous alipbatic compounds are rejected at logarithmically decreasing concentrations as the chain length is increased. In general the straight chain diols are more stimulating than the corresponding polyethylene and polypropylene glycols. This difference is related in some manner to the presence of ether linkages in the latter. Polypropylene glycols, with chains of three carbon atoms between the ether linkages are more stimulating than polyethylene glycols, where the spacing is —O—C—C—O—. Unipolymers are more stimulating than mixtures of homologues with the same average molecular weights. Polyethylene glycol 1540 is the largest molecule of measured molecular weight known to stimulate chemoreceptors. The introduction of a second terminal hydroxyl group into the straight hydrocarbon chain reduces the stimulating effect. Alcohols corresponding to the first three diols average about four times as stimulating as the latter while those corresponding to the higher diols average more than one hundred times as stimulating. PMID:18891141

  2. Chemical Modification with High Molecular Weight Polyethylene Glycol Reduces Transduction of Hepatocytes and Increases Efficacy of Intravenously Delivered Oncolytic Adenovirus

    PubMed Central

    Doronin, Konstantin; Shashkova, Elena V.; May, Shannon M.; Hofherr, Sean E.

    2009-01-01

    Abstract Oncolytic adenoviruses are anticancer agents that replicate within tumors and spread to uninfected tumor cells, amplifying the anticancer effect of initial transduction. We tested whether coating the viral particle with polyethylene glycol (PEG) could reduce transduction of hepatocytes and hepatotoxicity after systemic (intravenous) administration of oncolytic adenovirus serotype 5 (Ad5). Conjugating Ad5 with high molecular weight 20-kDa PEG but not with 5-kDa PEG reduced hepatocyte transduction and hepatotoxicity after intravenous injection. PEGylation with 20-kDa PEG was as efficient at detargeting adenovirus from Kupffer cells and hepatocytes as virus predosing and warfarin. Bioluminescence imaging of virus distribution in two xenograft tumor models in nude mice demonstrated that PEGylation with 20-kDa PEG reduced liver infection 19- to 90-fold. Tumor transduction levels were similar for vectors PEGylated with 20-kDa PEG and unPEGylated vectors. Anticancer efficacy after a single intravenous injection was retained at the level of unmodified vector in large established prostate carcinoma xenografts, resulting in complete elimination of tumors in all animals and long-term tumor-free survival. Anticancer efficacy after a single intravenous injection was increased in large established hepatocellular carcinoma xenografts, resulting in significant prolongation of survival as compared with unmodified vector. The increase in efficacy was comparable to that obtained with predosing and warfarin pretreatment, significantly extending the median of survival. Shielding adenovirus with 20-kDa PEG may be a useful approach to improve the therapeutic window of oncolytic adenovirus after systemic delivery to primary and metastatic tumor sites. PMID:19469693

  3. Evaluation of cytotoxicity of surfactants used in self-micro emulsifying drug delivery systems and their effects on paracellular transport in Caco-2 cell monolayer.

    PubMed

    Ujhelyi, Zoltán; Fenyvesi, Ferenc; Váradi, Judit; Fehér, Pálma; Kiss, Tímea; Veszelka, Szilvia; Deli, Mária; Vecsernyés, Miklós; Bácskay, Ildikó

    2012-10-09

    The objective of this study was to examine the cellular effects of the members of two non-ionic amphiphilic tenside groups and their mixtures on human Caco-2 cell monolayers as dependent upon their chemical structures and physicochemical properties. The first group of polyethylene glycol esters is represented by Polysorbates and Labrasol alone and in blends, while the members of the second group. Capryol 90, Capryol PGMC, Lauroglycol 90 and Lauroglycol FCC were used as propylene glycol esters. They are increasingly used in SMEDDS as recent tensides or co-tensides to increase hydrophobic bioavailability of a drug. Critical micelle concentration was measured by determination of surface tension. CMC refers to the ability of solubilization of surfactants. Cytotoxicity tests were performed on Caco-2 cell monolayers by MTT and LDH methods. Paracellular permeability as a marker of the integrity of cell monolayers, was examined with Lucifer yellow assays combined with TransEpithelial Electrical Resistance (TEER) measurements. The effect of these surfactants on tight junctions as evidence for paracellular pathway was also characterized. The results of cytotoxicity assays were in agreement, and showed significant differences among the cytotoxic properties of surfactants in a concentration-dependent manner. Polysorbates 20, 60, 80 are the most toxic compounds. In the case of Labrasol, the degree of esterification and lack of sorbit component decreased cytotoxicity. If the hydrophyl head was changed from polyethylene glycol to propylene glycol the main determined factor of cytotoxicity was the monoester content and the length of carbon chain. In our CMC experiments, we found that only Labrasol showed expressed cytotoxicity above the CMC. It refers to good ability of micelle solubilization of Labrasol. In our paracellular transport experiments each of polyethylene glycol surfactants (Polysorbates and Labrasol) altered TEER values, but propylene glycol esters did not modify the monolayer integrity. Polyethylene glycol esters alone and in blends (0.05% Labrasol--0.001% Polysorbates 20, 60, 80) were able to increase Lucifer yellow permeability significantly below the IC₅₀ concentration. On the other hand Labrasol and Polysorbates 20 have expressed effect on tight junctions of Caco-2 monolayer. It could be concluded that polyethylene glycol ester-type tensides were able to enhance the paracellular permeability by the redistribution of junctional proteins. Our results might ensure useful data for selection of suitable tensides, co-tensides and tenside mixtures for SMEDDS formulations. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Enhanced the performance of graphene oxide/polyimide hybrid membrane for CO2 separation by surface modification of graphene oxide using polyethylene glycol

    NASA Astrophysics Data System (ADS)

    Wu, Li-guang; Yang, Cai-hong; Wang, Ting; Zhang, Xue-yang

    2018-05-01

    Polyethylene glycol (PEG) with different molecular weights was first used to modify graphene oxide (GO) samples. Subsequently, polyimide (PI) hybrid membranes containing modified-GO were fabricated via in situ polymerization. The separation performance of these hybrid membranes was evaluated using permeation experiments for CO2 and N2 gases. The morphology characterization showed that PEG with suitable molecular weight could be successfully grafted on the GO surface. PEG modification altered the surface properties of GO and introduced defective structures onto GO surface. This caused strong surface polarity and high free volume of membranes containing PEG-modified GO, thereby improving the separation performance of membranes. The addition of PEG-GO with low molecular weight effectively increased gas diffusion through hybrid membranes. The hybrid membranes containing PEG-GO with large molecular weight had high solubility performance for CO2 gas due to the introduction of numerous polar groups into polymeric membranes. With the loading content of modified GO, the CO2 gas permeability of hybrid membranes initially increased but eventually decreased. The optimal content of modified GO in membranes reached 3.0 wt%. When too much PEG added (exceeding 30 g), some impurities formed on GO surface and some aggregates appeared in the resulting hybrid membrane, which depressed the membrane performance.

  5. Hyaluronic Acid (HA)-Polyethylene glycol (PEG) as injectable hydrogel for intervertebral disc degeneration patients therapy

    NASA Astrophysics Data System (ADS)

    Putri Kwarta, Cityta; Widiyanti, Prihartini; Siswanto

    2017-05-01

    Chronic Low Back Pain (CLBP) is one health problem that is often encountered in a community. Inject-able hydrogels are the newest way to restore the disc thickness and hydration caused by disc degeneration by means of minimally invasive surgery. Thus, polymers can be combined to improve the characteristic properties of inject-able hydrogels, leading to use of Hyaluronic Acid (a natural polymer) and Polyethylene glycol (PEG) with Horse Radish Peroxide (HRP) cross linker enzymes. The swelling test results, which approaches were the ideal disc values, were sampled with variation of enzyme concentrations of 0.25 µmol/min/mL. The enzyme concentrations were 33.95%. The degradation test proved that the sample degradation increased along with the decrease of the HRP enzyme concentration. The results of the cytotoxicity assay with MTT assay method showed that all samples resulted in the 90% of living cells are not toxic. In vitro injection, models demonstrated that higher concentration of the enzymes was less state of gel which would rupture when released from the agarose gel. The functional group characterization shows the cross linking bonding in sample with enzyme adding. The conclusion of this study is PEG-HA-HRP enzyme are safe polymer composites which have a potential to be applied as an injectable hydrogel for intervertebral disc degeneration.

  6. Polyethylene Oxide (PEO) and Polyethylene Glycol (PEG) Polymer Sieving Matrix for RNA Capillary Electrophoresis

    PubMed Central

    Yamaguchi, Yoshinori; Li, Zhenqing; Zhu, Xifang; Liu, Chenchen; Zhang, Dawei; Dou, Xiaoming

    2015-01-01

    The selection of sieving polymer for RNA fragments separation by capillary electrophoresis is imperative. We investigated the separation of RNA fragments ranged from 100 to 10,000 nt in polyethylene glycol (PEG) and polyethylene oxide (PEO) solutions with different molecular weight and different concentration. We found that the separation performance of the small RNA fragments (<1000 nt) was improved with the increase of polymer concentration, whereas the separation performance for the large ones (>4000 nt) deteriorated in PEG/PEO solutions when the concentration was above 1.0%/0.6%, respectively. By double logarithmic plot of mobility and RNA fragment size, we revealed three migration regimes for RNA in PEG (300-500k) and PEO (4,000k). Moreover, we calculated the smallest resolvable nucleotide length (N min) from the resolution length analysis. PMID:25933347

  7. Polyethylene glycol assisted growth of Sn-doped ZnO nanorod arrays prepared via sol-gel immersion method

    NASA Astrophysics Data System (ADS)

    Ismail, A. S.; Mamat, M. H.; Malek, M. F.; Saidi, S. A.; Yusoff, M. M.; Mohamed, R.; Sin, N. D. Md; Suriani, A. B.; Rusop, M.

    2018-05-01

    Tin-doped zinc oxide (SZO) nanorod films at different concentrations of polyethylene glycol (PEG) were successfully deposited on zinc oxide (ZnO) seeded layer catalyst using sol-gel immersion method. The morphology of the samples were characterized using field emission scanning electron microscopy (FESEM), optical properties using UV-Vis spectrophotometer and electrical properties using I-V measurement system. The current-voltage (I-V) characteristics displayed that 5 wt % sample produced the highest conductivity.

  8. Polymer Coatings Reduce Electro-osmosis

    NASA Technical Reports Server (NTRS)

    Herren, Blair J.; Snyder, Robert; Shafer, Steven G.; Harris, J. Milton; Van Alstine, James M.

    1989-01-01

    Poly(ethylene glycol) film controls electrostatic potential. Electro-osmosis in quartz or glass chambers reduced or reversed by coating inside surface of chambers with monomacromolecular layers of poly(ethylene glycol). Stable over long times. Electrostatic potential across surface of untreated glass or plastic chamber used in electro-phoresis is negative and attracts cations in aqueous electrolyte. Cations solvated, entrains flow of electrolyte migrating toward cathode. Electro-osmotic flow interferes with desired electrophoresis of particles suspended in electrolyte. Polymer coats nontoxic, transparent, and neutral, advantageous for use in electrophoresis.

  9. Liquid Viscosity and Density Measurement with Flexural-Plate-Wave Sensors

    DTIC Science & Technology

    1996-04-01

    capillary-viscometer-measured viscosity in Fig. 4. "The data from solutions of poly(ethylene glycol), having average molecular weights 3350 and 15,000...have seen similar results for the FPW-measured viscosity of salmon-sperm DNA solutions. 25 glycerol WA " PEG 3,350 H-4 . e! 2 PEG 15,000 IK- ,,,," HEC...number of aqueous solutions of the polymers poly(ethylene glycol) ( PEG ) and hydroxyethyl cellulose (HEC). The response of the FPW sensor (vertical axis

  10. Effect of the conditions of isolation on the physicochemical properties of human serum albumin in the norm and with pathology

    NASA Astrophysics Data System (ADS)

    Ivanov, A. I.; Zhbankov, R. G.; Korolenko, E. A.; Korolik, E. V.; Meleshchenko, L. A.; Sarnatskaya, V. V.; Nikolaev, V. G.; Nikolaichik, V. V.; Yushko, L. A.

    1997-01-01

    Differential scanning calorimetry and IR spectrosocopy were used to investigate the effect of the procedure of isolation of human serum albumin on its physicochemical characteristics. It is shown that fractionation of blood plasma with ethylene glycol followed by ion exchange chromatography can be used to obtain albumin of normal donors that is similar to the albumin in the nonfractionated plasma according to melting thermograms. Endotherms of human serum albumin samples that were obtained by affinity chromatography and preparative electrophoresis are bimodal, unlike the monophasic for albumin obtained by polyethylene glycol precipitation. These changes result from a higher content of nonetherified fatty acids in the albumin samples obtained by affinity chromatography and from modification of the secondary protein structure in the samples obtained by electrophoresis. Analysis of melting thermograms of serum albumin from patients with uremia, chronic hepatitis, and peritonitis shows that fractionation of blood with polyethylene glycol preserves the thermodynamic characteristics of the various pathological serum albumins to the greatest extent. The present results demonstrate the advantage of polyethylene glycol fractionation for isolation of native preparations of normal and “pathological” human serum albumin.

  11. Thermodynamics of single polyethylene and polybutylene glycols with hydrogen-bonding ends: A transition from looped to open conformations

    NASA Astrophysics Data System (ADS)

    Lee, Eunsang; Paul, Wolfgang

    2018-02-01

    A variety of linear polymer precursors with hydrogen bonding motifs at both ends enable us to design supramolecular polymer systems with tailored macroscopic properties including self-healing. In this study, we investigate thermodynamic properties of single polyethylene and polybutylene glycols with hydrogen bonding motifs. In this context, we first build a coarse-grained model of building blocks of the supramolecular polymer system based on all-atom molecular structures. The density of states of the single precursor is obtained using the stochastic approximation Monte Carlo method. Constructing canonical partition functions from the density of states, we find the transition from looped to open conformations at transition temperatures which are non-monotonously changing with an increasing degree of polymerization due to the competition between chain stiffness and loop-forming entropy penalty. In the complete range of chain length under investigation, a coexistence of the looped and open morphologies at the transition temperature is shown regardless of whether the transition is first-order-like or continuous. Polyethylene and polybutylene glycols show similar behavior in all the thermodynamic properties but the transition temperature of the more flexible polybutylene glycol is shown to change more gradually.

  12. Effect of silane coupling agents on the chemical and physical properties of photocrosslinked poly(dimethylsiloxane) dimethacrylate/poly(ethylene glycol) diacrylate hydrogel

    NASA Astrophysics Data System (ADS)

    Lim, K. W.; Hamid, Z. A. A.

    2017-07-01

    Inorganic-organic hydrogels based on dimethacrylated polydimethylsiloxane (PDMSMA) and diacrylated poly(ethylene glycol) (PEGDA) macromers were prepared via photocrosslinking method. Silane coupling agent was incorporated into the hydrogel formulations to overcome the phase incompatibility. Pure PEGDA (0:100) hydrogels showed the highest value of ESR %, while pure PDMSMA (100:0) hydrogels showed no swelling as we expected. Inclusion of more hydrophobic domains resulted in a lower value of ESR %, i.e. in 75:25 hybrid hydrogels. Beside, we had noticed 50:50 and 75:25 hybrid hydrogels disintegrate during swelling period. However, their integrity was improved and sustained after the coupling agent was added. Similarly, the value of E* for the hybrid hydrogels showed an increment after the coupling agent was incorporated, and this is in a good agreement with the SEM micrograph which display an improved interfacial adhesion.

  13. Poly(ethylene glycol) and cyclodextrin-grafted chitosan: from methodologies to preparation and potential biotechnological applications

    NASA Astrophysics Data System (ADS)

    Campos, Estefânia V. R.; Oliveira, Jhones L.; Fraceto, Leonardo F.

    2017-11-01

    Chitosan, a polyaminosaccharide obtained by alkaline deacetylation of chitin, possesses useful properties including biodegradability, biocompatibility, low toxicity, and good miscibility with other polymers. It is extensively used in many applications in biology, medicine, agriculture, environmental protection, and the food and pharmaceutical industries. The amino and hydroxyl groups present in the chitosan backbone provide positions for modifications that are influenced by factors such as the molecular weight, viscosity, and type of chitosan, as well as the reaction conditions. The modification of chitosan by chemical methods is of interest because the basic chitosan skeleton is not modified and the process results in new or improved properties of the material. Among the chitosan derivatives, cyclodextrin-grafted chitosan and poly(ethylene glycol)-grafted chitosan are excellent candidates for a range of biomedical, environmental decontamination, and industrial purposes. This work discusses modifications including chitosan with attached cyclodextrin and poly(ethylene glycol), and the main applications of these chitosan derivatives in the biomedical field.

  14. Hydrogels of poly(ethylene glycol): mechanical characterization and release of a model drug.

    PubMed

    Iza, M; Stoianovici, G; Viora, L; Grossiord, J L; Couarraze, G

    1998-03-02

    Thermosensitive polymer networks were synthesized from poly(ethylene glycol), hexamethylene diisocyanate and 1,2,6-hexanetriol in stoichiometric proportions. By varying the amount of 1,2,6-hexanetriol and the molar mass of the poly(ethylene glycol), a wide range of networks with different crosslinking densities was prepared. The networks obtained were characterized by the temperature dependence of their degree of equilibrium swelling in water and by their Young's moduli. For each network, the molecular weight between crosslinks was estimated. The structure of the hydrogels was analysed with respect to scaling laws, and it was found that the results obtained with PEG 1500 and PEG 6000 hydrogels are in agreement with theoretical predictions, whereas those obtained with PEG 400 hydrogels are in disagreement. The release properties of PEG hydrogels were studied by the determination of the diffusion coefficient for acebutolol chlorhydrate and by an analysis of the effect of temperature on these coefficients. Finally, these release properties were correlated with the swelling and structural properties of the hydrogels.

  15. Poly(ethylene glycol) and Cyclodextrin-Grafted Chitosan: From Methodologies to Preparation and Potential Biotechnological Applications

    PubMed Central

    Campos, Estefânia V. R.; Oliveira, Jhones L.; Fraceto, Leonardo F.

    2017-01-01

    Chitosan, a polyaminosaccharide obtained by alkaline deacetylation of chitin, possesses useful properties including biodegradability, biocompatibility, low toxicity, and good miscibility with other polymers. It is extensively used in many applications in biology, medicine, agriculture, environmental protection, and the food and pharmaceutical industries. The amino and hydroxyl groups present in the chitosan backbone provide positions for modifications that are influenced by factors such as the molecular weight, viscosity, and type of chitosan, as well as the reaction conditions. The modification of chitosan by chemical methods is of interest because the basic chitosan skeleton is not modified and the process results in new or improved properties of the material. Among the chitosan derivatives, cyclodextrin-grafted chitosan and poly(ethylene glycol)-grafted chitosan are excellent candidates for a range of biomedical, environmental decontamination, and industrial purposes. This work discusses modifications including chitosan with attached cyclodextrin and poly(ethylene glycol), and the main applications of these chitosan derivatives in the biomedical field. PMID:29164107

  16. Monolayers of derivatized poly(l-lysine)-grafted poly(ethylene glycol) on metal oxides as a class of biomolecular interfaces

    PubMed Central

    Ruiz-Taylor, L. A.; Martin, T. L.; Zaugg, F. G.; Witte, K.; Indermuhle, P.; Nock, S.; Wagner, P.

    2001-01-01

    We report on the design and characterization of a class of biomolecular interfaces based on derivatized poly(l-lysine)-grafted poly(ethylene glycol) copolymers adsorbed on negatively charged surfaces. As a model system, we synthesized biotin-derivatized poly(l-lysine)-grafted poly(ethylene glycol) copolymers, PLL-g-[(PEGm)(1−x) (PEG-biotin)x], where x varies from 0 to 1. Monolayers were produced on titanium dioxide substrates and characterized by x-ray photoelectron spectroscopy. The specific biorecognition properties of these biotinylated surfaces were investigated with the use of radiolabeled streptavidin alone and within complex protein mixtures. The PLL-g-PEG-biotin monolayers specifically capture streptavidin, even from a complex protein mixture, while still preventing nonspecific adsorption of other proteins. This streptavidin layer can subsequently capture biotinylated proteins. Finally, with the use of microfluidic networks and protein arraying, we demonstrate the potential of this class of biomolecular interfaces for applications based on protein patterning. PMID:11158560

  17. Radiation-induced graft copolymerization of poly(ethylene glycol) monomethacrylate onto deoxycholate-chitosan nanoparticles as a drug carrier

    NASA Astrophysics Data System (ADS)

    Pasanphan, Wanvimol; Rattanawongwiboon, Thitirat; Rimdusit, Pakjira; Piroonpan, Thananchai

    2014-01-01

    Poly(ethylene glycol) monomethacrylate-grafted-deoxycholate chitosan nanoparticles (PEGMA-g-DCCSNPs) were successfully prepared by radiation-induced graft copolymerization. The hydrophilic poly(ethylene glycol) monomethacrylate was grafted onto deoxycholate-chitosan in an aqueous system. The radiation-absorbed dose is an important parameter on degree of grafting, shell thickness and particle size of PEGMA-g-DCCSNPs. Owing to their amphiphilic architecture, PEGMA-g-DCCSNPs self-assembled into spherical core-shell nanoparticles in aqueous media. The particle size of PEGMA-g-DCCSNPs measured by TEM varied in the range of 70-130 nm depending on the degree of grafting as well as the irradiation dose. Berberine (BBR) as a model drug was encapsulated into the PEGMA-g-DCCSNPs. Drug release study revealed that the BBR drug was slowly released from PEGMA-g-DCCSNPs at a mostly constant rate of 10-20% in PBS buffer (pH 7.4) at 37 °C over a period of 23 days.

  18. Poly(ethylene glycol) and Cyclodextrin-Grafted Chitosan: From Methodologies to Preparation and Potential Biotechnological Applications.

    PubMed

    Campos, Estefânia V R; Oliveira, Jhones L; Fraceto, Leonardo F

    2017-01-01

    Chitosan, a polyaminosaccharide obtained by alkaline deacetylation of chitin, possesses useful properties including biodegradability, biocompatibility, low toxicity, and good miscibility with other polymers. It is extensively used in many applications in biology, medicine, agriculture, environmental protection, and the food and pharmaceutical industries. The amino and hydroxyl groups present in the chitosan backbone provide positions for modifications that are influenced by factors such as the molecular weight, viscosity, and type of chitosan, as well as the reaction conditions. The modification of chitosan by chemical methods is of interest because the basic chitosan skeleton is not modified and the process results in new or improved properties of the material. Among the chitosan derivatives, cyclodextrin-grafted chitosan and poly(ethylene glycol)-grafted chitosan are excellent candidates for a range of biomedical, environmental decontamination, and industrial purposes. This work discusses modifications including chitosan with attached cyclodextrin and poly(ethylene glycol), and the main applications of these chitosan derivatives in the biomedical field.

  19. Separation and quantitation of polyethylene glycols 400 and 3350 from human urine by high-performance liquid chromatography.

    PubMed

    Ryan, C M; Yarmush, M L; Tompkins, R G

    1992-04-01

    Polyethylene glycol 3350 (PEG 3350) is useful as an orally administered probe to measure in vivo intestinal permeability to macromolecules. Previous methods to detect polyethylene glycol (PEG) excreted in the urine have been hampered by inherent inaccuracies associated with liquid-liquid extraction and turbidimetric analysis. For accurate quantitation by previous methods, radioactive labels were required. This paper describes a method to separate and quantitate PEG 3350 and PEG 400 in human urine that is independent of radioactive labels and is accurate in clinical practice. The method uses sized regenerated cellulose membranes and mixed ion-exchange resin for sample preparation and high-performance liquid chromatography with refractive index detection for analysis. The 24-h excretion for normal individuals after an oral dose of 40 g of PEG 3350 and 5 g of PEG 400 was 0.12 +/- 0.04% of the original dose of PEG 3350 and 26.3 +/- 5.1% of the original dose of PEG 400.

  20. Identification of polypropylene glycols and polyethylene glycol carboxylates in flowback and produced water from hydraulic fracturing.

    PubMed

    Thurman, E Michael; Ferrer, Imma; Rosenblum, James; Linden, Karl; Ryan, Joseph N

    2017-02-05

    The purpose of the study was to separate and identify the unknown surfactants present in flowback and produced water from oil and gas wells in the Denver-Julesburg Basin (Niobrara Formation) in Weld County, Colorado, USA. Weld County has been drilled extensively during the last five years for oil and gas between 7000-8000 feet below land-surface. Polypropylene glycols (PPGs) and polyethylene glycols carboxylates (PEG-Cs) were found for the first time in these flowback and produced water samples. These ethoxylated surfactants may be used as friction reducers, clay stabilizers, and surfactants. Ultrahigh-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (UHPLC/QTOF-MS) was used to separate and identify the different classes of PPGs, PEG-Cs, and their isomers. The Kendrick mass scale was applied along with mass spectrometry/mass spectrometry (MS-MS) with accurate mass for rapid and unequivocal identification. The PPGs and their isomers occur at the ppm concentration range and may be useful as "fingerprints" of hydraulic-fracturing. Comparing these detections to the compounds used in the fracturing process from FracFocus 3.0 (https://fracfocus.org), it appears that both PPGs and polyethylene glycols (PEGs) are commonly named as additives, but the PEG-Cs have not been reported. The PEG-Cs may be trace impurities or degradation products of PEGs. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Effect of temperature and aging time on the rheological behavior of aqueous poly(ethylene glycol)/Laponite RD dispersions.

    PubMed

    Morariu, Simona; Bercea, Maria

    2012-01-12

    The viscoelastic properties of 2% poly(ethylene glycol) aqueous solutions containing Laponite RD from 1% to 4% were investigated by oscillatory and flow measurements in the temperature range of 15-40 °C. The enhancement of the clay content from mixture causes the increase of the viscoelastic moduli and the change of the flow from liquid-like behavior (Maxwellian fluid) to a solid-like one at a set temperature. The longest relaxation times (τ(1)) of the mixtures with low clay concentrations (1% and 2%) are not affected by changes in temperature unlike the samples having high content of clay at which τ(1) increases above 30 °C and below 17.5 °C. The characteristic behavior of the mixtures with the high clay concentration could be explained by considering the effect of Brownian motion on the network structure formed in these dispersions as well as by the poor solubility of poly(ethylene glycol) in water at high temperatures. The flow activation energy was determined and discussed. An abrupt increase of the flow activation energy was evidenced between 2% and 3% Laponite RD. The rheological measurements carried out at different rest times showed a decrease of the gelation time from 1 week to 2 h when the clay concentration increases from 2% to 4%. The aging kinetics of poly(ethylene glycol)/Laponite RD/water mixtures, investigated at 25 °C, revealed the increase of the viscosity-rate kinetic constant by increasing the clay concentration.

  2. Multiarm-polyethylene glycol-polyglutamic acid peptide dendrimer: Design, synthesis, and dissolving thrombus.

    PubMed

    Zhang, Shao-Fei; Lü, Shaoyu; Gao, Chunmei; Yang, Jiandong; Yan, Xiang; Li, Tao; Wen, Na; Huang, Mengjie; Liu, Mingzhu

    2018-06-01

    Thrombotic events affect many individuals in a number of ways, all of which can cause significant morbidity and mortality. Nattokinase (NK), as a novel thrombolytic drug, has been used for thrombolytic therapy. It not only possesses plasminogen activator activity, but also directly digests fibrin through limited proteolysis. However, it may undergo inactivation and denaturation in the harsh external environment. In this study, a multiarm-polyethylene glycol-polyglutamic acid peptide dendrimer was fabricated and used as a carrier for NK protection and delivery. Different arm numbers of polyethylene glycol-polyglutamic acid peptide dendrimers (x-PEG(G 3 ) x , x = 2, 4, 6, 8) were designed, prepared, and characterized by 1 H NMR and FTIR. Then, x-PEG(G 3 ) x were loaded with NK to form nanocomposites. Their size and morphology were determined by dynamic light scattering and transmission electron microscopy. Enzyme activity was evaluated via UV-Vis absorbance spectra, fluorescence spectra, circular dichroism spectra, and zeta potential measurements. The study reveals that the obtained x-PEG(G 3 ) x /NK nanocomposites possess high enzyme activity. In addition, the nanocomposites show increased viability of rat macrophage cells, and excellent thrombolysis ability in vitro and in vivo. This work establishes a multiarm-polyethylene glycol-polyglutamic acid peptide dendrimer with potential application in NK carrier and thrombolytic therapy. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1687-1696, 2018. © 2018 Wiley Periodicals, Inc.

  3. Photodynamic therapy of tumors with pyropheophorbide-a-loaded polyethylene glycol-poly(lactic-co-glycolic acid) nanoparticles.

    PubMed

    Liu, Hui; Zhao, Mei; Wang, Jin; Pang, Mingpei; Wu, Zhenzhou; Zhao, Liqing; Yin, Zhinan; Hong, Zhangyong

    Photodynamic therapy (PDT) has many advantages in treating cancers, but the lack of ideal photosensitizers continues to be a major limitation restricting the clinical utility of PDT. This study aimed to overcome this obstacle by generating pyropheophorbide- a -loaded polyethylene glycol-poly(lactic- co -glycolic acid) nanoparticles (NPs) for efficient tumor-targeted PDT. The fabricated NPs were efficiently internalized in the mitochondrion by cancer cells, and they efficiently killed cancer cells in a dose-dependent manner when activated with light. Systemically delivered NPs were highly enriched in tumor sites, and completely ablated the tumors in a xenograft KB tumor mouse model when illuminated with 680 nm light (156 mW/cm 2 , 10 minutes). The results suggested that this tumor-specific NP-delivery system for pyropheophorbide- a has the potential to be used in tumor-targeted PDT.

  4. Synthesis and characterization of amphiphilic block polymer poly(ethylene glycol)-poly(propylene carbonate)-poly(ethylene glycol) for drug delivery.

    PubMed

    Li, Hongchun; Niu, Yongsheng

    2018-08-01

    A novel amphiphilic block polymer poly(ethylene glycol)-poly(propylene carbonate)-poly(ethylene glycol) (PEG-PPC-PEG) was synthesized via the dicyclohexylcarbodiimide condensation reaction of double PEG-bis-amine and HOOC-PPC-COOH. The obtained copolymer was characterized by NMR to determine its structure. Using the PEG-PPC-PEG as the carrier and using doxorubicin (DOX) as a model drug, DOX-loaded nanoparticles with core shell structure were synthesized by self-assembly in water. The nanoparticles properties such as particle size, drug loading, encapsulation efficiency (EE) and drug release behavior were investigated as a function of the hydrophobic block length of PPC segments and compared with each other. The results showed that the EE was up to 88.8%. Nanoparticles were found to have a certain effect on the controlled release of DOX. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Extraction processes and solvents for recovery of cesium, strontium, rare earth elements, technetium and actinides from liquid radioactive waste

    DOEpatents

    Zaitsev, Boris N.; Esimantovskiy, Vyacheslav M.; Lazarev, Leonard N.; Dzekun, Evgeniy G.; Romanovskiy, Valeriy N.; Todd, Terry A.; Brewer, Ken N.; Herbst, Ronald S.; Law, Jack D.

    2001-01-01

    Cesium and strontium are extracted from aqueous acidic radioactive waste containing rare earth elements, technetium and actinides, by contacting the waste with a composition of a complex organoboron compound and polyethylene glycol in an organofluorine diluent mixture. In a preferred embodiment the complex organoboron compound is chlorinated cobalt dicarbollide, the polyethylene glycol has the formula RC.sub.6 H.sub.4 (OCH.sub.2 CH.sub.2).sub.n OH, and the organofluorine diluent is a mixture of bis-tetrafluoropropyl ether of diethylene glycol with at least one of bis-tetrafluoropropyl ether of ethylene glycol and bis-tetrafluoropropyl formal. The rare earths, technetium and the actinides (especially uranium, plutonium and americium), are extracted from the aqueous phase using a phosphine oxide in a hydrocarbon diluent, and reextracted from the resulting organic phase into an aqueous phase by using a suitable strip reagent.

  6. Release mechanisms of acetaminophen from polyethylene oxide/polyethylene glycol matrix tablets utilizing magnetic resonance imaging.

    PubMed

    Tajiri, Tomokazu; Morita, Shigeaki; Sakamoto, Ryosaku; Suzuki, Masazumi; Yamanashi, Shigeyuki; Ozaki, Yukihiro; Kitamura, Satoshi

    2010-08-16

    Release mechanism of acetaminophen (AAP) from extended-release tablets of hydrogel polymer matrices containing polyethylene oxide (PEO) and polyethylene glycol (PEG) were achieved using flow-through cell with magnetic resonance imaging (MRI). The hydrogel forming abilities are observed characteristically and the layer thickness which is corresponding to the diffusion length of AAP has a good correlation with the drug release profiles. In addition, polymeric erosion contribution to AAP releasing from hydrogel matrix tablets was directly quantified using size-exclusion chromatography (SEC). The matrix erosion profile indicates that the PEG erosion kinetic depends primarily on the composition ratio of PEG to PEO. The present study has confirmed that the combination of in situ MRI and SEC should be well suited to investigate the drug release mechanisms of hydrogel matrix such as PEO/PEG. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  7. Preparation and evaluation of gelling granules to improve oral administration.

    PubMed

    Ito, Ikumi; Ito, Akihiko; Unezaki, Sakae

    2015-06-01

    We investigated the preparation of oral granules that are solid when stored and that will swell and gel via water absorption, to address problems experienced by patients when taking medication. Important physical properties of gelling granules include elasticity that is normally smooth, quick water absorption and swelling properties that allow easy swallowing. We selected gelatin (GEL), succinylated gelatin (SUC-GEL) and ι-carrageenan (CAR) as matrix polymers that can undergo gelation at room temperature or at cold temperatures. Saccharide and polyethylene glycol (PEG) were added to prepare the experimental granules. The best matrix gelling granule was SUC-GEL. When xylitol (XYL), sorbitol (SOR) and maltitol (MAL) were added, elasticity was improved, and PEG improved the granule's water absorption behavior, which is an important element involved in gelation. The best granules were prepared by selecting SUC-GEL as the matrix and adding a small amount of PEG and XYL in amounts equal to that of SUC-GEL.

  8. Formation of low charge state ions of synthetic polymers using quaternary ammonium compounds.

    PubMed

    Nasioudis, Andreas; Joyce, William F; van Velde, Jan W; Heeren, Ron M A; van den Brink, Oscar F

    2010-07-01

    Factors such as high polymer dispersity and variation in elemental composition (of copolymers) often complicate the electrospray ionization mass spectrometry (ESI-MS) analysis of synthetic polymers with high molar mass. In the experiments described in this study, quaternary ammonium compounds were observed to facilitate the production of low charge state pseudomolecular ions when added to the spray solution for ESI-MS. This approach was then used for the ESI time-of-flight mass spectrometry (TOF-MS) analysis of synthetic polymers. Hexadecyltrimethylammonium chloride permitted the successful analysis of poly(ethylene glycol) of 2-40 kDa, poly(propylene glycol) and poly(tetramethylene glycol) oligomers. Increasing the quaternary ammonium compounds' concentration results in the production of low charge state pseudomolecular ions. A comparison of structurally different quaternary ammonium compounds showed that the best performance is expected from large molecules with specific charge localization, which leaves the charge available for interactions. The applicability of the method for the MS analysis of other polymeric systems was also studied. In the case of poly(tetramethylene glycol), the method not only shifted the distributions to higher m/z values but also allowed the detection of high molecular weight material that was not observed without addition of the modifier to the spray solution.

  9. Spectrofluorimetric determination of hydrogen peroxide with 2-hydroxy-1-naphthaldehyde salicyloylhydrazone (HNSH) as the substrate for horseradish peroxidase (HRP).

    PubMed

    Tang, Bo; Wang, Yan; Sun, Ying; Shen, Han Xi

    2002-01-01

    The oxidation reaction of HNSH with H2O2 under the catalysis of HRP was studied in detail. The possible reaction mechanism was discussed. Under optimum experimental conditions, the oxidized product of HNSH had excitation and emission maxima at 296 and 414 nm, respectively. A study to prove the existence of -O-O-H in polyethylene glycols was carried out. The proposed method was successfully applied to the determination of -O-O-H in polyethylene glycols.

  10. Non-invasive control of influence of polyethylene glycol on transport function of fluorescent colored liposomal nanoparticles

    NASA Astrophysics Data System (ADS)

    Stelmashchuk, O.; Zherebtsov, E.; Zherebtsova, A.; Kuznetsova, E.; Vinokurov, A.; Dunaev, A.; Mamoshin, A.; Snimshchikova, I.; Borsukov, A.; Bykov, A.; Meglinski, I.

    2017-03-01

    The studies were carried out on groups of clinically healthy mice line of outbred CD-1 stock. The model animals were divided into 2 groups and received experimental liposomal formulations. Using the method of fluorescence spectroscopy, we investigated the effectiveness of penetration into the circulatory system of fluorescently stained liposomes with polyethylene glycol (PEG) and without PEG when administered orally. Fluorescence channel with a fiber probe series of multifunctional laser non-invasive diagnostic system "LAKK-M" (SPE "LAZMA" Ltd, Russia) was used as the measuring equipment.

  11. Ionic conductivity and dielectric permittivity of polymer electrolyte plasticized with polyethylene glycol

    NASA Astrophysics Data System (ADS)

    Das, S.; Ghosh, A.

    2016-05-01

    We have studied ionic conductivity and dielectric permittivity of PEO-LiClO4 solid polymer electrolyte plasticized with polyethylene glycol (PEG). The temperature dependence of the ionic conductivity has been well interpreted using Vogel-Tamman-Fulcher equation. The maximum dielectric constant is observed for 30 wt. % of PEG content. To get further insights into the ion dynamics, the complex dielectric permittivity has been studied with Havriliak-Negami function. The variation of relaxation time with inverse temperature obtained from HN formalism follows VTF nature.

  12. Reactive molecular simulation on the calcium silicate hydrates/polyethylene glycol composites

    NASA Astrophysics Data System (ADS)

    Zhou, Yang; Hou, Dongshuai; Jiang, Jinyang; She, Wei; Yu, Jiao

    2017-11-01

    Calcium silicate hydrates (C-S-H) may potentially exhibit extraordinary performance when modified by polymers, in which way the properties of cement-based materials can be improved from the genetic level. In this molecular dynamics simulation of the interaction between C-S-H and polyethylene glycol, apart from the H bond network connection in the interface, another chemical adsorption was observed. Calcium of C-S-H broke the Csbnd O bond of PEG and formed a new Casbnd C connection, which created a stronger link between the organic and inorganic phases.

  13. Process for recovering chaotropic anions from an aqueous solution also containing other ions

    DOEpatents

    Rogers, Robin; Horwitz, E. Philip; Bond, Andrew H.

    1999-01-01

    A solid/liquid process for the separation and recovery of chaotropic anions from an aqueous solution is disclosed. The solid support comprises separation particles having surface-bonded poly(ethylene glycol) groups, whereas the aqueous solution from which the chaotropic anions are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved salt (lyotrope). A solid/liquid phase admixture of separation particles containing bound chaotropic anions in such an aqueous solution is also contemplated, as is a chromatography apparatus containing that solid/liquid phase admixture.

  14. Process for recovering chaotropic anions from an aqueous solution also containing other ions

    DOEpatents

    Rogers, R.; Horwitz, E.P.; Bond, A.H.

    1999-03-30

    A solid/liquid process for the separation and recovery of chaotropic anions from an aqueous solution is disclosed. The solid support comprises separation particles having surface-bonded poly(ethylene glycol) groups, whereas the aqueous solution from which the chaotropic anions are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved salt (lyotrope). A solid/liquid phase admixture of separation particles containing bound chaotropic anions in such an aqueous solution is also contemplated, as is a chromatography apparatus containing that solid/liquid phase admixture. 19 figs.

  15. [Study of the effect of surface-active agents on living cells, used as component parts in microemulsions, based on their chemical structures and critical micelle-formative concentration (CMC)].

    PubMed

    Ujhelyi, Zoltán; Vecsernyés, Miklós; Bácskay, Ildikó

    2013-01-01

    The aim of this study was to examine the cellular effects of two nonionic amphiphilic tenside groups and their mixtures on human Caco-2 cell monolayers as dependent upon their chemical structures and physicochemical properties. The first group of polyethylene glycol esters is represented by Polysorbates and Labrasol alone and in blends, while the members of the second group:Capryol 90, Capryol PGMC, Lauroglycol 90 and Lauroglycol FCC were used as propylene glycol esters. They are increasingly used in SMEDDS as recent tensides or co-tensides to increase the solubility of hydrophobic drug. Critical micelle concentration was measured by determination of surface tension. CMC refers to the ability of solubilization of surfactants. Cytotoxicity tests were performed on Caco-2 cell monolayers by MTT and LDH methods. Caco-2 cell monolayers are convenient and reliable in vitro models of the gastrointestinal tract. Paracellular permeability was examined with Lucifer yellow assays. The integrity of cell monolayers was observed by TransEpithelial Electrical Resistance (TEER) measurements. Tight junction alterations effected by the surfactants were also characterized as evidence for paracellular pathway. Changes in sub cellular localization of the tight junction proteins: ZO-1, Claudin-land beta-cathenin, were examined by confocal laser scanning microscopy.The results of cytotoxicity assays were in agreement and showed significant differences among the cytotoxic properties of surfactants in a concentration-dependent manner. Polysorbates 20, 60, 80 are the most toxic compounds. In the case of Labrasol, the degree of esterification and lack of sorbit component decreased cytotoxicity. If the hydrophyl head was changed from polyethylene glycol to propylene glycol, the main determined factor of cytotoxicity was the monoester content and the length of carbon chain. In our CMC experiments, we found that only Labrasol showed expressed cytotoxicity above the CMC. It refers to good ability of micelle solubilization of Labrasol. In our paracellular transport experiments each of polyethylene glycol surfactants (Polysorbates and Labrasol) altered TEER values but propylene glycol esters did not modify the monolayer integrity. Polyethylene glycol esters alone and in blends (0.05% Labrasol--0.001% Polysorbates 20, 60, 80) were able to increase Lucifer yellow permeability significantly below the IC50 concentration. On the other hand Labrasol and Polysorbates 20 have expressed effect on tight junctions of Caco-2 monolayer. It could be concluded that polyethylene glycol ester-type tensides were able to enhance the paracellular permeability by the redistribution of junctional proteins. Our results might ensure useful data for selection of suitable tensides, co-tensides and tenside mixtures for SMEDDS formulations.

  16. The effect on colon visualization during colonoscopy of the addition of simethicone to polyethylene glycol-electrolyte solution: a randomized single-blind study.

    PubMed

    Matro, Rebecca; Tupchong, Keegan; Daskalakis, Constantine; Gordon, Victoria; Katz, Leo; Kastenberg, David

    2012-11-29

    Colonic bubbles associated with polyethylene glycol-electrolyte solution (PEG-ELS) are common and obscure mucosal visualization. This study aimed to determine whether adding simethicone decreases the incidence of bubbles. Prospective, single-blind, randomized comparison of split dose PEG-ELS vs. PEG-ELS+simethicone (PEG-S) for outpatient colonoscopy. Bubble severity for colonic segments was assessed on withdrawal as A=no/minimal bubbles, B=moderate bubbles/interfere with detecting 5 mm polyp, C=severe bubbles/interfere with detecting 10 mm polyp. Primary end point was Grade B or C bubbles in any colon segment. Secondary end points were cleansing quality, incidence and severity of side effects, and polyp detection. One hundred and thirty nine patients enrolled; 13 withdrew before colonoscopy. Of 123 patients evaluated, 62 took PEG-S and 61 PEG-ELS. The incidence of grade B or C bubbles was much lower with PEG-S compared with PEG-ELS (2% vs. 38%; P=0.001). Overall cleansing (excellent or good) quality was not significantly different for either the whole colon (89% PEG-ELS, 94% of PEG-S, P=0.529) or right colon (88% PEG-ELS, 94% PEG-S, P=0.365). More PEG-S patients had excellent rather than good preps (whole colon 53% vs. 28%, P=0.004; right colon 53% vs. 35%, P=0.044). Need for any flushing was less with PEG-S (38% vs. 70%, P=0.001). The groups were not significantly different with respect to total procedure and withdrawal times, incidence or severity of side effects, or number of polyps/patient or adenomas/patient. Adding simethicone to PEG-ELS effectively eliminates bubbles, substantially reduces the need for flushing, and results in more excellent preparations.

  17. The Effect on Colon Visualization During Colonoscopy of the Addition of Simethicone to Polyethylene Glycol-Electrolyte Solution: A Randomized Single-Blind Study

    PubMed Central

    Matro, Rebecca; Tupchong, Keegan; Daskalakis, Constantine; Gordon, Victoria; Katz, Leo; Kastenberg, David

    2012-01-01

    OBJECTIVES: Colonic bubbles associated with polyethylene glycol-electrolyte solution (PEG-ELS) are common and obscure mucosal visualization. This study aimed to determine whether adding simethicone decreases the incidence of bubbles. METHODS: Prospective, single-blind, randomized comparison of split dose PEG-ELS vs. PEG-ELS+simethicone (PEG-S) for outpatient colonoscopy. Bubble severity for colonic segments was assessed on withdrawal as A=no/minimal bubbles, B=moderate bubbles/interfere with detecting 5 mm polyp, C=severe bubbles/interfere with detecting 10 mm polyp. Primary end point was Grade B or C bubbles in any colon segment. Secondary end points were cleansing quality, incidence and severity of side effects, and polyp detection. RESULTS: One hundred and thirty nine patients enrolled; 13 withdrew before colonoscopy. Of 123 patients evaluated, 62 took PEG-S and 61 PEG-ELS. The incidence of grade B or C bubbles was much lower with PEG-S compared with PEG-ELS (2% vs. 38% P=0.001). Overall cleansing (excellent or good) quality was not significantly different for either the whole colon (89% PEG-ELS, 94% of PEG-S, P=0.529) or right colon (88% PEG-ELS, 94% PEG-S, P=0.365). More PEG-S patients had excellent rather than good preps (whole colon 53% vs. 28%, P=0.004; right colon 53% vs. 35%, P=0.044). Need for any flushing was less with PEG-S (38% vs. 70%, P=0.001). The groups were not significantly different with respect to total procedure and withdrawal times, incidence or severity of side effects, or number of polyps/patient or adenomas/patient. CONCLUSIONS: Adding simethicone to PEG-ELS effectively eliminates bubbles, substantially reduces the need for flushing, and results in more excellent preparations. PMID:23238113

  18. Folic-Acid-Targeted Self-Assembling Supramolecular Carrier for Gene Delivery.

    PubMed

    Liao, Rongqiang; Yi, Shouhui; Liu, Manshuo; Jin, Wenling; Yang, Bo

    2015-07-27

    A targeting gene carrier for cancer-specific delivery was successfully developed through a "multilayer bricks-mortar" strategy. The gene carrier was composed of adamantane-functionalized folic acid (FA-AD), an adamantane-functionalized poly(ethylene glycol) derivative (PEG-AD), and β-cyclodextrin-grafted low-molecular-weight branched polyethylenimine (PEI-CD). Carriers produced by two different self-assembly schemes, involving either precomplexation of the PEI-CD with the FA-AD and PEG-AD before pDNA condensation (Method A) or pDNA condensation with the PEI-CD prior to addition of the FA-AD and PEG-AD to engage host-guest complexation (Method B) were investigated for their ability to compact pDNA into nanoparticles. Cell viability studies show that the material produced by the Method A assembly scheme has lower cytotoxicity than branched PEI 25 kDa (PEI-25KD) and that the transfection efficiency is maintained. These findings suggest that the gene carrier, based on multivalent host-guest interactions, could be an effective, targeted, and low-toxicity carrier for delivering nucleic acid to target cells. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Small bowel cleansing for capsule endoscopy in paediatric patients: a prospective randomized single-blind study.

    PubMed

    Oliva, Salvatore; Cucchiara, Salvatore; Spada, Cristiano; Hassan, Cesare; Ferrari, Federica; Civitelli, Fortunata; Pagliaro, Giuseppe; Di Nardo, Giovanni

    2014-01-01

    Small bowel cleansing by capsule endoscopy has never been addressed in children. Randomized controlled trial to evaluate the effect of five bowel preparation regimens on the mucosal visibility surface (as percentage of visualized surface area). Group A: a clear liquid diet for 12 h on the day before; Group B: high volume polyethylene glycol (50 mL/kg, up to 2Lt/die); Group C: low volume polyethylene glycol (25 mL/kg up to 1Lt/die); Group D: 20 mL (376 mg) of oral simethicone; Group E: 25 mL/kg (up to 1Lt/die) of polyethylene glycol solution plus 20 mL (376 mg) of oral simethicone. Overall, 198 patients (53% male, median age 13 years) were enrolled. Preparation regimen visualization scores were 14.1 ± 4.2, 18.9 ± 5.1, 17.8 ± 5.5, 14.9 ± 4.8 and 20.9 ± 4.6 in groups A, B, C, D and E, respectively (P < 0.01). Positive findings were found in 172 cases (87%), but no significant differences were observed in the diagnostic yield and tolerability. Interobserver agreement, k = 0.89 (95% CI 0.83 ± 0.71). This is the first report in children that supports the use of 25 mL/kg (up to 1Lt/die) of polyethylene glycol solution plus 20 mL (376 mg) of oral simethicone as the preparation of choice for capsule endoscopy. Copyright © 2013 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  20. Water and UV degradable lactic acid polymers

    DOEpatents

    Bonsignore, P.V.; Coleman, R.D.

    1994-11-01

    A water and UV light degradable copolymer of monomers of lactic acid and a modifying monomer were selected from the class consisting of ethylene and polyethylene glycols, propylene and polypropylene glycols, P-dioxanone, 1,5 dioxepan-2-one, 1,4 -oxathialan-2-one, 1,4-dioxide and mixtures. These copolymers are useful for waste disposal and agricultural purposes. Also disclosed is a water degradable blend of polylactic acid or modified polylactic acid and high molecular weight polyethylene oxide where the high molecular weight polyethylene oxide is present in the range of from about 2% by weight to about 50% by weight, suitable for films. A method of applying an active material selected from the class of seeds, seedlings, pesticides, herbicides, fertilizers and mixtures to an agricultural site is also disclosed.

  1. Water and UV degradable lactic acid polymers

    DOEpatents

    Bonsignore, Patrick V.; Coleman, Robert D.

    1994-01-01

    A water and UV light degradable copolymer of monomers of lactic acid and a modifying monomer selected from the class consisting of ethylene and polyethylene glycols, propylene and polypropylene glycols, P-dioxanone, 1,5 dioxepan-2-one, 1,4 -oxathialan-2-one, 1,4-dioxide and mixtures thereof. These copolymers are useful for waste disposal and agricultural purposes. Also disclosed is a water degradable blend of polylactic acid or modified polylactic acid and high molecular weight polyethylene oxide wherein the high molecular weight polyethylene oxide is present in the range of from about 2% by weight to about 50% by weight, suitable for films. A method of applying an active material selected from the class of seeds, seedlings, pesticides, herbicides, fertilizers and mixtures thereof to an agricultural site is also disclosed.

  2. Mechanical, Rheological, and Bioactivity Properties of Ultra High-Molecular-Weight Polyethylene Bioactive Composites Containing Polyethylene Glycol and Hydroxyapatite

    PubMed Central

    Ahmad, Mazatusziha; Wahit, Mat Uzir; Abdul Kadir, Mohammed Rafiq; Mohd Dahlan, Khairul Zaman

    2012-01-01

    Ultrahigh-molecular-weight polyethylene/high-density polyethylene (UHMWPE/HDPE) blends prepared using polyethylene glycol PEG as the processing aid and hydroxyapatite (HA) as the reinforcing filler were found to be highly processable using conventional melt blending technique. It was demonstrated that PEG reduced the melt viscosity of UHMWPE/HDPE blend significantly, thus improving the extrudability. The mechanical and bioactive properties were improved with incorporation of HA. Inclusion of HA from 10 to 50 phr resulted in a progressive increase in flexural strength and modulus of the composites. The strength increment is due to the improvement on surface contact between the irregular shape of HA and polymer matrix by formation of mechanical interlock. The HA particles were homogenously distributed even at higher percentage showed improvement in wetting ability between the polymer matrix and HA. The inclusion of HA enhanced the bioactivity properties of the composite by the formation of calcium phosphate (Ca-P) precipitates on the composite surface as proven from SEM and XRD analysis. PMID:22666129

  3. Effect of molecular weight of polyethylene glycol on the rheological properties of fumed silica-polyethylene glycol shear thickening fluid

    NASA Astrophysics Data System (ADS)

    Singh, Mansi; Verma, Sanjeev K.; Biswas, Ipsita; Mehta, Rajeev

    2018-05-01

    The steady-shear viscosity and dynamic visco-elastic behavior of suspensions of 20 wt% fumed silica-polyethylene glycol (PEG200) shear thickening fluid (STF) with different concentrations of various molecular weight PEG (4600, 6000 and 10000) has been studied. The results demonstrate that with an increase in the molecular weight of dispersing medium, the shear thickening parameters are significantly enhanced. In steady-state rheology, addition of PEG6000 as an additive results in high shear thickening at both low and high temperatures whereas in dynamic state, PEG4600 gives high values of all dynamic parameters. Additionally, long polymer can interconnect several particles, acting as cross-links which explain the mechanism of the enhancement in viscosity. Interestingly, compositions having PEG10000 as additive exhibits shear thinning rheology. Long polymer chains increases hydrodynamic forces thus aggregation of particles increases. Also, the results demonstrate the effect of high molecular weight PEGs on the elasticity and stability of the STF, which is important with regard to high impact resisting applications.

  4. Isoniazid release from suppositories compounded with selected bases.

    PubMed

    Hudson, Kristofer C; Asbill, C Scott; Webster, Andrew A

    2007-01-01

    There is an increasing need for an alternative route of isoniazid adminstration for prophylaxis and treatment of tuberculosis in children. The purpose of this study is to evaluate the in vitro release of isoniazid from extemporaneously compounded isoniazid suppositories with a goal of optimizing the suppository dosage form for this indication. Suppositories were compounded using three different base formulations (cocoa butter, Witepsol H15 Base F, and a combination of polyethylene glycols 3350, 1000, and 400). The release profiles of six compounded suppositories with isoniazid (100 mg) were tested with a United States Pharmacopeial Convention-approved dissolution apparatus. Isoniazid concentrations at predetermined time points were determined using high-performance liquid chromatographic analysis. The results show that drug release from the water-solutble base (mixed polyethylene glycols) was significantly greater than that from the lipophilic bases (cocoa butter and Witepsol H15). The percentage of isoniazid release form the polyethylene glycol suppository formulation (70 +/- 1.4 mg/mL) was greater than that from the cocoa butter (55 +/- 1.1 mg/mL) and Witepsol H15 Base F (18 +/- 0.36 mg/mL) suppository formulations.

  5. Separation of polyethylene glycols and amino-terminated polyethylene glycols by high-performance liquid chromatography under near critical conditions.

    PubMed

    Wei, Y-Z; Zhuo, R-X; Jiang, X-L

    2016-05-20

    The separation and characterization of polyethylene glycols (PEGs) and amino-substituted derivatives on common silica-based reversed-phase packing columns using isocratic elution is described. This separation is achieved by liquid chromatography under the near critical conditions (LCCC), based on the number of amino functional end groups without obvious effect of molar mass for PEGs. The mobile phase is acetonitrile in water with an optimal ammonium acetate buffer. The separation mechanism of PEG and amino-substituted PEG under the near LCCC on silica-based packing columns is confirmed to be ion-exchange interaction. Under the LCCC of PEG backbone, with fine tune of buffer concentration, the retention factor ratios for benzylamine and phenol in buffered mobile phases, α(benzylamine/phenol)-values, were used to assess the ion-exchange capacity on silica-based reversed-phase packing columns. To the best of our knowledge, this is the first report on separation of amino-functional PEGs independent of the molar mass by isocratic elution using common C18 or phenyl reversed-phase packing columns. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. The bundling of actin with polyethylene glycol 8000 in the presence and absence of gelsolin.

    PubMed Central

    Goverman, J; Schick, L A; Newman, J

    1996-01-01

    Actin filament and bundle formation occur in the cytosol under conditions of very high total macromolecular concentration. In this study we have utilized the inert molecule polyethylene glycol 8000 (PEG) as a means of simulating crowded conditions in vitro. Column-purified Ca-actin was polymerized in the absence and presence of gelsolin (to regulate mean filament lengths between 50 and 5000 mers) and PEG (2-8%) using various concentrations of KCl and/or 2 mM divalent cations. Bundling was characterized by the scattered light intensity and mean diffusion coefficients obtained from dynamic light scattering, as well as by fluorescence and phase-contrast microscopy. The minimum concentration of KCl required for bundling decreases both with increasing concentration of PEG at a fixed mean filament length, and with decreasing filament length at a fixed concentration of PEG. In the absence of divalent cation, bundling is reversible on dilution, as determined by intensity levels, diffusion coefficients, and microscopy. However, with either 2 mM Mg2+ or Ca2+ added, bundling is irreversible under conditions of higher PEG concentrations or longer filaments, indicating that osmotic pressure effects cannot fully explain actin bundling with PEG. Weaker divalent cation-binding sites on actin as well as disulfide bonds appear to be involved in the irreversible bundling. Images FIGURE 7 PMID:8874022

  7. Entry of (/sup 3/H)water and (1,2-/sup 14/C)polyethylene glycol 4000 into normal and cystic fibrosis salivary mucus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lukie, B.E.

    1983-03-01

    This investigation was performed to compare the entry of (/sup 3/H)water and (/sup 14/C)PEG into samples of salivary mucus from patients with CF and normal subjects. A solution containing both radioisotopes was added to samples and salivary mucus and mixed, and entry of each into mucus was determined by their dilution in the supernatant at 1, 2, 4, and 24 hr. (/sup 3/H)water rapidly entered and equilibrated with the water content of both normal and CF mucus. (/sup 14/C)PEG entered mucus more slowly than (/sup 3/H)water and by 24 hr had entered at a ratio of only 0.794 +/- 0.108more » and 0.766 +/- 0.039 of the water space accessible to (/sup 3/H)water in normal and CF mucus, respectively. The mechanisms responsible for the partial exclusion of the large polyethylene glycol molecule were not explored but may reflect restriction of access to a portion of mucus water. Thus water entry and solute exclusion, both determinants of permeability, were unaltered in CF mucus, which fact provides evidence against the presence of a generalized defect of mucus permeability in this disease. The techniques developed for this study may be adaptable to the study of the permeability properties of mucus from other sources and other gels.« less

  8. Entry of (/sup 3/H)water and (1,2-/sup 14/C)polyethylene glycol 4000 into normal and cystic fibrosis salivary mucus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lukie, B.E.

    1983-03-01

    This investigation was performed to compare the entry of (/sup 3/H)water and (/sup 14/C)PEG into samples of salivary mucus from patients with CF and normal subjects. A solution containing both radioisotopes was added to samples of salivary mucus and mixed, and entry of each into mucus was determined by their dilution in the supernatant at 1, 2, 4, and 24 hr. (/sup 3/H)water rapidly entered and equilibrated with the water content of both normal and CF mucus. (/sup 14/C)PEG entered mucus more slowly than (/sup 3/H)water and by 24 hr had entered at a ratio of only 0.794 +/- 0.108more » and 0.766 +/- 0.039 of the water space accessible to (/sup 3/H)water in normal and CF mucus, respectively. The mechanisms responsible for the partial exclusion of the large polyethylene glycol molecule were not explored but may reflect steric restriction of access to a portion of mucus water. Thus water entry and solute exclusion, both determinants of permeability, were unaltered in CF mucus, which fact provides evidence against the presence of a generalized defect of mucus permeability in this disease. The techniques developed for this study may be adaptable to the study of the permeability properties of mucus from other sources and other gels.« less

  9. CL-20/DNB co-crystal based PBX with PEG: molecular dynamics simulation

    NASA Astrophysics Data System (ADS)

    Zhang, Jiang; Gao, Pei; Xiao, Ji Jun; Zhao, Feng; Xiao, He Ming

    2016-12-01

    Molecular dynamics simulation was carried out for CL-20/DNB co-crystal based PBX (polymer-bonded explosive) blended with polymer PEG (polyethylene glycol). In this paper, the miscibility of the PBX models is investigated through the calculated binding energy. Pair correlation function (PCF) analysis is applied to study the interaction of the interface structures in the PBX models. The mechanical properties of PBXs are also discussed to understand the change of the mechanical properties after adding the polymer. Moreover, the calculated diffusion coefficients of the interfacial explosive molecules are used to discuss the dispersal ability of CL-20 and DNB molecules in the interface layer.

  10. Comparison of retention models for polymers 1. Poly(ethylene glycol)s.

    PubMed

    Bashir, Mubasher A; Radke, Wolfgang

    2006-10-27

    The suitability of three different retention models to predict the retention times of poly(ethylene glycol)s (PEGs) in gradient and isocratic chromatography was investigated. The models investigated were the linear (LSSM) and the quadratic solvent strength model (QSSM). In addition, a model describing the retention behaviour of polymers was extended to account for gradient elution (PM). It was found that all models are suited to properly predict gradient retention volumes provided the extraction of the analyte specific parameters is performed from gradient experiments as well. The LSSM and QSSM on principle cannot describe retention behaviour under critical or SEC conditions. Since the PM is designed to cover all three modes of polymer chromatography, it is therefore superior to the other models. However, the determination of the analyte specific parameters, which are needed to calibrate the retention behaviour, strongly depend on the suitable selection of initial experiments. A useful strategy for a purposeful selection of these calibration experiments is proposed.

  11. [Study on optimization of formulation of Danggui Liuhuang effervescent granules].

    PubMed

    Zheng, Ping; Meng, Li-Juan; Sun, Guo-Ping; Wang, Wen-Zhong

    2011-03-01

    To optimize the formulation of Danggui Liuhuang effervescent granules. By means of quadratic regression rotation-orthogonal combination design, the effect of the proper proportion between citric acid and sodium bicarbonate, as well as the proper quantity of polyethylene glycol 6000 and sodium cyclamate on the dissolubility and pH of effervescent granules was studied. The best formulation was as follows: citric acid: sodium bicarbonate = 0.75: 1, the percentage of polyethylene glycol 6000 and cyclamate was 3.25% and 0.89%, respectively. The dissolubility and pH of the effervescent granules are better and the taste is satisfactory.

  12. Isolation and preliminary characterization of circulating immune complexes from rabbits with experimental syphilis.

    PubMed Central

    Baughn, R E; Musher, D M

    1983-01-01

    Immune complexes isolated from sera of rabbits with experimental, disseminated syphilis were found to have sedimentation coefficients greater than 19s. By radioimmunoblot assays, materials precipitated with 2.5% polyethylene glycol or chromatographed on DEAE-Affi-Gel Blue were found to contain albumin, C3, immunoglobulin M (IgM), IgG, and treponemal antigen(s), whereas control materials contained only albumin and IgG. When polyethylene glycol precipitation of immune complexes from syphilitic rabbits was followed by immobilization on protein A and acid elution, radioimmunoblots detected only IgG and treponemal antigen(s). Images PMID:6358025

  13. Influence of polymerization conditions on the refractive index of poly(ethylene glycol) diacrylate (PEGDA) hydrogels

    NASA Astrophysics Data System (ADS)

    Zhang, Zhi Feng; Ma, Xinxian; Wang, Haibin; Ye, Fei

    2018-04-01

    This paper studies the influences of fabrication parameters on the optical properties of poly(ethylene glycol) diacrylate(PEGDA) hydrogels during polymerization, including the irradiation intensity, irradiation time, photoinitiator concentration, and water content. The refractive index of PEGDA hydrogels polymerized under various conditions is measured, with the results shown to be valuable for future research applying PEGDA hydrogels as optical materials. In addition, it is found that the photoinitiator concentration used can be as low as 1.0 wt%, which is severalfold lower than that previously reported, making PEGDA hydrogels more desirable for bioapplications.

  14. Polyethylene Glycol Propionaldehydes

    NASA Technical Reports Server (NTRS)

    Harris, Joe M.; Sedaghat-Herati, Mohammad R.; Karr, Laurel J.

    1992-01-01

    New class of compounds derived from polyethylene glycol (PEG's) namely, PEG-propionaldehydes, offers two important advantages over other classes of PEG aldehyde derivatives: compounds exhibit selective chemical reactivity toward amino groups and are stable in aqueous environment. PEG's and derivatives used to couple variety of other molecules, such as, to tether protein molecules to surfaces. Biotechnical and biomedical applications include partitioning of two phases in aqueous media; immobilization of such proteins as enzymes, antibodies, and antigens; modification of drugs; and preparation of protein-rejecting surfaces. In addition, surfaces coated with PEG's and derivatives used to control wetting and electroosmosis. Another potential application, coupling to aminated surfaces.

  15. Simethicone to prevent colonic bubbles during CT colonography performed with polyethylene glycol lavage and iohexol tagging: a randomized clinical trial.

    PubMed

    Hong, Gil-Sun; Park, Seong Ho; Kim, Bohyun; Lee, Ju Hee; Kim, Jin Cheon; Yu, Chang Sik; Baek, Seunghee; Lee, Jong Seok; Kim, Hyun Jin

    2015-04-01

    The purpose of this study was to determine whether the occurrence of numerous colonic bubbles during CT colonography (CTC) performed with polyethylene glycol cleansing and oral iohexol fecal/fluid tagging could be prevented by use of simethicone. Adults with suspected colonic neoplasia who had been randomly assigned to control and simethicone intervention groups underwent CTC after cleansing with 4 L of polyethylene glycol, tagging with 50 mL of 350 mg I/mL oral iohexol, and without (control) or with (intervention) oral administration of 200 mg of simethicone. Colonic segments in the control and intervention groups were evaluated for amount of colonic bubbles during CTC. A 6-point grading system was used in which 0 indicated no bubbles and 5 indicated that more than three fourths of the air-distended mucosa was covered with bubbles. The primary endpoint was a per-patient colonic bubble grade, derived as an average of the segmental grades. Eighty adults with suspected colonic neoplasia were randomly assigned to the control (40 patients) and simethicone intervention (40 patients) groups. A total of 659 colonic segments in the control group and 689 segments in the intervention group were evaluated for amount of colonic bubbles during CTC. The per-patient colonic bubble score was significantly lower in the simethicone intervention group than in the control group. The mean score was 0.0±0.1 (SD) versus 1.2±0.8 (p<0.001; 95% CI for the mean difference, -1.4 to -1.0). In the intervention group, 673 (97.7%) segments were grade 0, and 16 (2.3%) were grade 1. In contrast, in the control group, 226 (34.3%) segments were grade 0; 173 (26.3%), grade 1; 175 (26.6%), grade 2; 45 (6.8%), grade 3; 23 (3.5%), grade 4; and 17 (2.6%), grade 5. The colonic bubbles associated with fecal/fluid tagging with iohexol can be successfully prevented by adding simethicone to the colonic preparation.

  16. Extrusion foaming of protein-based thermoplastic and polyethylene blends

    NASA Astrophysics Data System (ADS)

    Gavin, Chanelle; Lay, Mark C.; Verbeek, Casparus J. R.

    2016-03-01

    Currently the extrusion foamability of Novatein® Thermoplastic Protein (NTP) is being investigated at the University of Waikato in collaboration with the Biopolymer Network Ltd (NZ). NTP has been developed from bloodmeal (>86 wt% protein), a co-product of the meat industry, by adding denaturants and plasticisers (tri-ethylene glycol and water) allowing it to be extruded and injection moulded. NTP alone does not readily foam when sodium bicarbonate is used as a chemical blowing agent as its extensional viscosity is too high. The thermoplastic properties of NTP were modified by blending it with different weight fractions of linear low density polyethylene (LLDPE) and polyethylene grafted maleic anhydride (PE-g-MAH) compatibiliser. Extrusion foaming was conducted in two ways, firstly using the existing water content in the material as the blowing agent and secondly by adding sodium bicarbonate. When processed in a twin screw extruder (L/D 25 and 10 mm die) the material readily expanded due to the internal moisture content alone, with a conditioned expansion ratio of up to ± 0.13. Cell structure was non-uniform exhibiting a broad range cell sizes at various stages of formation with some coalescence. The cell size reduced through the addition of sodium bicarbonate, overall more cells were observed and the structure was more uniform, however ruptured cells were also visible on the extrudate skin. Increasing die temperature and introducing water cooling reduced cell size, but the increased die temperature resulted in surface degradation.

  17. Separation of no-carrier-added rhenium from bulk tantalum by the sodium malonate-PEG aqueous biphasic system.

    PubMed

    Dutta, Binita; Lahiri, Susanta; Tomar, B S

    2014-02-01

    The aqueous biphasic system (ABS) involving sodium malonate-polyethylene glycol (PEG) phases has been applied for the first time for separation of no-carrier-added (183)Re (T1/2=70 d) from α-particle irradiated bulk tantalum target. The various ABS conditions were applied for investigating the separation by varying pH, temperature, PEG-molecular weight, concentration of salt. The extraction pattern was hardly affected by change in pH and the molecular weight of PEG. One step separation of nca (183)Re from Ta was achieved at the optimal conditions of (i) 50% (w/w) PEG-4000-2 M sodium malonate, 40 °C and (ii) 50% (w/w) PEG-4000-3 M sodium malonate, room temperature (27 °C). © 2013 Published by Elsevier Ltd.

  18. 21 CFR 172.275 - Synthetic paraffin and succinic derivatives.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Synthetic paraffin and succinic derivatives. 172... succinic derivatives. Synthetic paraffin and succinic derivatives identified in this section may be safely... acid derivatives of isopropyl alcohol, polyethylene glycol, and polypropylene glycol. It consists of a...

  19. 21 CFR 172.275 - Synthetic paraffin and succinic derivatives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Synthetic paraffin and succinic derivatives. 172... succinic derivatives. Synthetic paraffin and succinic derivatives identified in this section may be safely... acid derivatives of isopropyl alcohol, polyethylene glycol, and polypropylene glycol. It consists of a...

  20. Star-shaped poly(oligoethylene glycol) copolymer-based gels: Thermo-responsive behaviour and bioapplicability for risedronate intranasal delivery.

    PubMed

    Soliman, Mahmoud E; Elmowafy, Enas; Casettari, Luca; Alexander, Cameron

    2018-05-30

    The aim of this work was to obtain an intranasal delivery system with improved mechanical and mucoadhesive properties that could provide prolonged retention time for the delivery of risedronate (RS). For this, novel in situ forming gels comprising thermo-responsive star-shaped polymers, utilizing either polyethylene glycol methyl ether (PEGMA-ME 188, Mn 188) or polyethylene glycol ethyl ether (PEGMA-EE 246, Mn 246), with polyethylene glycol methyl ether (PEGMA-ME 475, Mn 475), were synthesized and characterized. RS was trapped in the selected gel-forming solutions at a concentration of 0.2% w/v. The pH, rheological properties, in vitro drug release, ex vivo permeation as well as mucoadhesion were also examined. MTT assays were conducted to verify nasal tolerability of the developed formulations. Initial in vivo studies were carried out to evaluate anti-osteoporotic activity in a glucocorticoid induced osteoporosis model in rats. The results showed successful development of thermo-sensitive formulations with favorable mechanical properties at 37 °C, which formed non-irritant, mucoadhesive porous networks, facilitating nasal RS delivery. Moreover, sustained release of RS, augmented permeability and marked anti-osteoporotic efficacy as compared to intranasal (IN) and intravenous (IV) RS solutions were realized. The combined results show that the in situ gels should have promising application as nasal drug delivery systems. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Efficacy of morning-only 4 liter sulfa free polyethylene glycol vs 2 liter polyethylene glycol with ascorbic acid for afternoon colonoscopy

    PubMed Central

    Rivas, John M; Perez, Alejandro; Hernandez, Marlow; Schneider, Alison; Castro, Fernando J

    2014-01-01

    AIM: To compare the bowel cleansing efficacy of same day ingestion of 4-L sulfa-free polyethylene glycol (4-L SF-PEG) vs 2-L polyethylene glycol solution with ascorbic acid (2-L PEG + Asc) in patients undergoing afternoon colonoscopy. METHODS: 206 patients (mean age 56.7 years, 61% male) undergoing outpatient screening or surveillance colonoscopies were prospectively randomized to receive either 4-L SF-PEG (n = 104) or 2-L PEG + Asc solution (n = 102). Colonoscopies were performed by two blinded endoscopists. Bowel preparation was graded using the Ottawa scale. Each participant completed a satisfaction and side effect survey. RESULTS: There was no difference in patient demographics amongst groups. 4-L SF-PEG resulted in better Ottawa scores compared to 2-L PEG + Asc, 4.2 vs 4.9 (P = 0.0186); left colon: 1.33 vs 1.57 respectively (P = 0.0224), right colon: 1.38 vs 1.63 respectively (P = 0.0097). No difference in Ottawa scores was found for the mid colon or amount of fluid. Patient satisfaction was similar for both arms but those assigned to 4-L SF-PEG reported less bloating: 23.1% vs 11.5% (P = 0.0235). Overall polyp detection, adenomatous polyp and advanced adenoma detection rates were similar between the two groups. CONCLUSION: Morning only 4-L SF-PEG provided superior cleansing with less bloating as compared to 2-L PEG + Asc bowel preparation for afternoon colonoscopy. Thus, future studies evaluating efficacy of morning only preparation for afternoon colonoscopy should use 4-L SF-PEG as the standard comparator. PMID:25132784

  2. Long-term hepatotoxicity of polyethylene-glycol functionalized multi-walled carbon nanotubes in mice

    NASA Astrophysics Data System (ADS)

    Zhang, Danying; Deng, Xiaoyong; Ji, Zongfei; Shen, Xizhong; Dong, Ling; Wu, Minghong; Gu, Taoying; Liu, Yuanfang

    2010-04-01

    The toxicity of polyethylene-glycol functionalized (PEGylated) multi-walled carbon nanotubes (MWCNTs) and non-PEGylated MWCNTs in vivo was evaluated and compared. Mice were exposed to MWCNTs by intravenous injection. The activity level of glutathione, superoxide dismutase and gene expression in liver, as well as some biochemical parameters and the tumor necrosis factor alpha level in blood were measured over 2 months. The pathological and electron micrographic observations of liver evidently indicate that the damage caused by non-PEGylated MWCNTs is slightly more severe than that of PEGylated MWCNTs, which means that PEGylation can partly, but not substantially, improve the in vivo biocompatibility of MWCNTs.

  3. Performance of cellulose acetate membrane with different additives for palm oil mill effluent (POME) liquid waste treatment

    NASA Astrophysics Data System (ADS)

    Aprilia, N. A. S.; Fauzi; Azmi, N.; Najwan, N.; Amin, A.

    2018-03-01

    Performance of cellulose acetate membrane for treatment of POME liquid has studied with different additives. Cellulose acetate membranes were prepared with different additive ie formamide and polyethylene glycol and used acetone as solvent. The function of formamide and polyethylene glycol (PEG) is to increase the porosity of the membrane surface. Performance of the membrane were included SEM, FT-IR and coefficient permeability. Membrane performance has been performed for percent rejection of total suspended solid (TSS) and turbidity of POME liquid waste. Cellulose acetate with formamide shows an increased percentage of rejection in removing TSS and turbidity than cellulose acetate with PEG.

  4. Aspects of Solvent Chemistry for Calcium Hydroxide Medicaments

    PubMed Central

    Athanassiadis, Basil

    2017-01-01

    Calcium hydroxide pastes have been used in endodontics since 1947. Most current calcium hydroxide endodontic pastes use water as the vehicle, which limits the dissolution of calcium hydroxide that can be achieved and, thereby, the maximum pH that can be achieved within the root canal system. Using polyethylene glycol as a solvent, rather than water, can achieve an increase in hydroxyl ions release compared to water or saline. By adopting non-aqueous solvents such as the polyethylene glycols (PEG), greater dissolution and faster hydroxyl ion release can be achieved, leading to enhanced antimicrobial actions, and other improvements in performance and biocompatibility. PMID:29065542

  5. Dynamic adsorption of mixtures of Rhodamine B, Pb (II), Cu (II) and Zn(II) ions on composites chitosan-silica-polyethylene glycol membrane

    NASA Astrophysics Data System (ADS)

    Mahatmanti, F. W.; Rengga, W. D. P.; Kusumastuti, E.; Nuryono

    2018-04-01

    The adsorption of a solution mixture of Rhodamine B, Pb (II), Cu (II) and Zn(II) was studied using dynamic methods employing chitosan-silica-polyethylene glycol (Ch/Si/P) composite membrane as an adsorptive membrane. The composite Ch/Si/P membrane was prepared by mixing a chitosan-based membrane with silica isolated from rice husk ash (ASP) and polyethylene glycol (PEG) as a plasticizer. The resultant composite membrane was a stronger and more flexible membrane than the original chitosan-based membrane as indicated by the maximum percentage of elongation (20.5 %) and minimum Young’s Modulus (80.5 MPa). The composite membrane also showed increased mechanical and hydrophilic properties compared to the chitosan membranes. The membrane was used as adsorption membrane for Pb (II), Cu (II), Cd (II) ions and Rhodamine B dyes in a dynamic system where the permeation and selectivity were determined. The permeation of the components was observed to be in the following order: Rhodamine B > Cd (II) > Pb (II) > Cu (II) whereas the selectivity was shown to decrease the order of Cu (II) > Pb (II) > Cd (II) > Rhodamine B.

  6. Solvent-like ligand-coated ultrasmall cadmium selenide nanocrystals: strong electronic coupling in a self-organized assembly.

    PubMed

    Lawrence, Katie N; Johnson, Merrell A; Dolai, Sukanta; Kumbhar, Amar; Sardar, Rajesh

    2015-07-21

    Strong inter-nanocrystal electronic coupling is a prerequisite for delocalization of exciton wave functions and high conductivity. We report 170 meV electronic coupling energy of short chain poly(ethylene glycol) thiolate-coated ultrasmall (<2.5 nm in diameter) CdSe semiconductor nanocrystals (SNCs) in solution. Cryo-transmission electron microscopy analysis showed the formation of a pearl-necklace assembly of nanocrystals in solution with regular inter-nanocrystal spacing. The electronic coupling was studied as a function of CdSe nanocrystal size where the smallest nanocrystals exhibited the largest coupling energy. The electronic coupling in spin-cast thin-film (<200 nm in thickness) of poly(ethylene glycol) thiolate-coated CdSe SNCs was studied as a function of annealing temperature, where an unprecedentedly large, ∼400 meV coupling energy was observed for 1.6 nm diameter SNCs, which were coated with a thin layer of poly(ethylene glycol) thiolates. Small-angle X-ray scattering measurements showed that CdSe SNCs maintained an order array inside the films. The strong electronic coupling of SNCs in a self-organized film could facilitate the large-scale production of highly efficient electronic materials for advanced optoelectronic device application.

  7. Plasmid DNA partitioning and separation using poly(ethylene glycol)/poly(acrylate)/salt aqueous two-phase systems.

    PubMed

    Johansson, Hans-Olof; Matos, Tiago; Luz, Juliana S; Feitosa, Eloi; Oliveira, Carla C; Pessoa, Adalberto; Bülow, Leif; Tjerneld, Folke

    2012-04-13

    Phase diagrams of poly(ethylene glycol)/polyacrylate/Na(2)SO(4) systems have been investigated with respect to polymer size and pH. Plasmid DNA from Escherichia coli can depending on pH and polymer molecular weight be directed to a poly(ethylene glycol) or to a polyacrylate-rich phase in an aqueous two-phase system formed by these polymers. Bovine serum albumin (BSA) and E. coli homogenate proteins can be directed opposite to the plasmid partitioning in these systems. Two bioseparation processes have been developed where in the final step the pDNA is partitioned to a salt-rich phase giving a total process yield of 60-70%. In one of them the pDNA is partitioned between the polyacrylate and PEG-phases in order to remove proteins. In a more simplified process the plasmid is partitioned to a PEG-phase and back-extracted into a Na(2)SO(4)-rich phase. The novel polyacrylate/PEG system allows a strong change of the partitioning between the phases with relatively small changes in composition or pH. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. The effectiveness of simethicone in improving visibility during colonoscopy.

    PubMed

    Park, Jae Jun; Lee, Sang Kil; Jang, Jae Young; Kim, Hyo Jong; Kim, Nam Hoon

    2009-01-01

    In colonoscopy examination, luminal visibility is frequently limited due to intraluminal bubbles. In present study was evaluated factors affecting bubble formation and the effects of simethicone in preventing bubble formation during colonoscopy. Consecutive patients (n=164) who received polyethylene glycol or sodium phosphate for bowel preparation were prospectively enrolled. Before colonoscopy, 57 patients took 80 mg simethicone after ingestion of bowel preparation solution and 107 did not to determine whether simethicone decreased bubble formation. Intraluminal gas bubbles were assessed and graded as follows: 0, minimal or none; 1, covering less than half the lumen; 2, covering at least half the lumen or the entire circumference. Grade 2 bubbles were regarded as significant, limiting visibility. Sodium phosphate preparation tended to have more bubbles than the polyethylene glycol. Significant bubbles were more likely to occur in males than females (p = 0.020). Significant bubbles were noted in 34.6% of patients without simethicone and 7% of patients with simethicone. Simethicone significantly lowered the incidence of bubbles during colonoscopy when given after a preparation solution (p < 0.05), The present study findings indicate that taking simethicone after an oral polyethylene glycol or sodium phosphate preparation can improve colonic visibility by diminishing colonic bubbles.

  9. Peptide multifunctionalized gold nanorods decrease toxicity of β-amyloid peptide in a Caenorhabditis elegans model of Alzheimer's disease.

    PubMed

    Morales-Zavala, Francisco; Arriagada, Hector; Hassan, Natalia; Velasco, Carolina; Riveros, Ana; Álvarez, Alejandra R; Minniti, Alicia N; Rojas-Silva, Ximena; Muñoz, Luis L; Vasquez, Rodrigo; Rodriguez, Katherine; Sanchez-Navarro, Macarena; Giralt, Ernest; Araya, Eyleen; Aldunate, Rebeca; Kogan, Marcelo J

    2017-10-01

    The properties of nanometric materials make nanotechnology a promising platform for tackling problems of contemporary medicine. In this work, gold nanorods were synthetized and stabilized with polyethylene glycols and modified with two kinds of peptides. The D1 peptide that recognizes toxic aggregates of Aβ, a peptide involved in Alzheimer's disease (AD); and the Angiopep 2 that can be used to deliver nanorods to the mammalian central nervous system. The nanoconjugates were characterized using absorption spectrophotometry, dynamic light scattering, and transmission electron microscopy, among other techniques. We determined that the nanoconjugate does not affect neuronal viability; it penetrates the cells, and decreases aggregation of Aβ peptide in vitro. We also showed that when we apply our nanosystem to a Caenorhabditis elegans AD model, the toxicity of aggregated Aβ peptide is decreased. This work may contribute to the development of therapies for AD based on metallic nanoparticles. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. BULK SYNTHESIS OF SILVER NANORODS IN POLY(ETHYLENE GLYCOL) USING MICROWAVE IRRADIATION

    EPA Science Inventory

    Microwave-assisted (MW), surfactantless, greener approach to bulk synthesis of silver nanorods employing poly (ethylene glycol) (PEG) is described. An aqueous solution of silver nitrate (AgNO-3,- 0.1 M, 4 mL) and 4 mL of PEG (molecular weight 300) were mixed at room temperature t...

  11. Analytical mass spectrometry of poly(ethylene glycol) additives in artists' acrylic emulsion media, artists' paints, and microsamples from acrylic paintings using MALDI-MS and nanospray-ESI-MS

    NASA Astrophysics Data System (ADS)

    Hoogland, F. G.; Boon, J. J.

    2009-07-01

    Poly(ethylene glycol) (PEG) compounds in artists' acrylic emulsion paint products from different paint manufacturers, ranging from base emulsions (Rohm and Haas, Röhm and Scott Bader), to modified emulsions and complete paints (Rowney, Winsor and Newton, Golden, Liquitex, Lascaux), were characterised with a newly developed mass spectrometric method which combines data from Matrix assisted laser desorption/ionisation mass spectrometry (MALDI-MS) and nano-electrospray ionisation mass spectrometry (nano-ESI-MS(MS)). MALDI-MS was used for the determination of the molar mass distribution (MMD) and calculation of the molar mass averages (Mw and Mn), the polydispersity index (D) and the relative amount of a specific distribution if multiple PEGs were present. Electrospray ionisation mass spectrometry was used for the end-group analysis. Three different classes of polymers was found being PEG, polypropylene glycol (PPG) and a block copolymer of polyethylene glycol/polypropylene glycol (PEG/PPG) with molar mass averages ranging from 400 to 4200 Da. PEG compounds with a nonylphenyl or an octylphenyl hydrophobic end-group are most common. The hydrophilic end-groups observed are hydroxide and/or sulphate. Water extracts of microsamples from a palette by David Hockney dating from 1970 and samples paintings by Patrick Caulfield (1936-2005) and John Hoyland (born in 1934) were investigated with the same technique. Although some artist paint manufacturers use the same specific base emulsions to make their paints, the composition of the PEG compounds present in the water extracts of the palette and paintings samples made it possible, in some cases, to suggest a specific brand of paint used by the artist.

  12. Directed aggregation of carbon nanotube on curved surfaces by polymer induced depletion attraction

    NASA Astrophysics Data System (ADS)

    Lee, Hsin-Chieh; Jiang, Hong-Ren

    2017-12-01

    In this study, we show that by chemically grafting macromolecule, polyethylene glycol (PEG), onto CNTs, PEG-CNTs become dispersible in an aqueous solution with tunable depletion interactions with each other. The aggregation of the PEG-CNTs can be controlled by adding PEG polymers into the solution. PEG-CNTs not only aggregate with each other but also tend to aggregate on curved surfaces. Due to this property, we show that PEG-CNTs can be directed to aggregate on particles and patterned surfaces. Depletion interaction induced aggregation of PEG-CNTs may provide a method to place PEG-CNTs on a specific position for different applications ranging from biomedical to industrial usages.

  13. Cytoprotective function of heme oxygenase 1 induced by a nitrated cyclic nucleotide formed during murine salmonellosis.

    PubMed

    Zaki, Mohammad Hasan; Fujii, Shigemoto; Okamoto, Tatsuya; Islam, Sabrina; Khan, Shahzada; Ahmed, Khandaker Ahtesham; Sawa, Tomohiro; Akaike, Takaaki

    2009-03-15

    Signaling mechanisms of NO-mediated host defense are yet to be elucidated. In this study, we report a unique signal pathway for cytoprotection during Salmonella infection that involves heme oxygenase 1 (HO-1) induced by a nitrated cyclic nucleotide, 8-nitroguanosine 3',5'-cyclic monophosphate (8-nitro-cGMP). Wild-type C57BL/6 mice and C57BL/6 mice lacking inducible NO synthase (iNOS) were infected with Salmonella enterica serovar Typhimurium LT2. HO-1 was markedly up-regulated during the infection, the level being significantly higher in wild-type mice than in iNOS-deficient mice. HO-1 up-regulation was associated with 8-nitro-cGMP formation detected immunohistochemically in Salmonella-infected mouse liver and peritoneal macrophages. 8-Nitro-cGMP either exogenously added or formed endogenously induced HO-1 in cultured macrophages infected with Salmonella. HO-1 inhibition by polyethylene glycol-conjugated zinc-protoporphyrin IX impaired intracellular killing of bacteria in mouse liver and in both RAW 264 cells and peritoneal macrophages. Infection-associated apoptosis was also markedly increased in polyethylene glycol-conjugated zinc-protoporphyrin IX-treated mouse liver cells and cultured macrophages. This effect of HO-1 inhibition was further confirmed by using HO-1 short interfering RNA in peritoneal macrophages. Our results suggest that HO-1 induced by NO-mediated 8-nitro-cGMP formation contributes, via its potent cytoprotective function, to host defense during murine salmonellosis.

  14. A Micro-Polyethylene Glycol Precipitation Assay as a Relative Solubility Screening Tool for Monoclonal Antibody Design and Formulation Development.

    PubMed

    Toprani, Vishal M; Joshi, Sangeeta B; Kueltzo, Lisa A; Schwartz, Richard M; Middaugh, C Russell; Volkin, David B

    2016-08-01

    Adequate protein solubility is an important prerequisite for development, manufacture, and administration of biotherapeutic drug candidates, especially for high-concentration protein formulations. A previously established method for determining the relative apparent solubility (thermodynamic activity) of proteins using polyethylene glycol (PEG) precipitation is adapted for screening and comparing monoclonal antibody (mAb) candidates where only limited quantities (≤1 mg) are available. This micro-PEG assay is used to evaluate various broadly neutralizing mAb candidates to HIV-1 viral spike (gp120 and gp41 glycoproteins). Using ∼1 mg of VRC01-WT mAb per assay, the precision of the micro-PEG assay was established. A series of 7 different broadly neutralizing mAbs to the HIV-1 viral spike proteins were compared by curve shape (%PEG vs. protein concentration), %PEGmidpoint determinations, and extrapolated apparent solubility values. Numerous formulation conditions were then evaluated for their relative effects on the VRC01-WT mAb. The PEGmidpt and apparent solubility values of VRC01-WT mAb decreased as the solution pH increased and increased as NaCl and arginine were added. A final optimization of the micro-PEG assay established that amounts as low as 0.1-0.2 mg can be used. Thus, the micro-PEG assay has significant potential as a relative solubility screening tool during candidate selection and early formulation development. Copyright © 2016 American Pharmacists Association®. All rights reserved.

  15. Reduction of Streptococcus mutans adherence and dental biofilm formation by surface treatment with phosphorylated polyethylene glycol.

    PubMed

    Shimotoyodome, Akira; Koudate, Takashi; Kobayashi, Hisataka; Nakamura, Junji; Tokimitsu, Ichiro; Hase, Tadashi; Inoue, Takashi; Matsukubo, Takashi; Takaesu, Yoshinori

    2007-10-01

    Initial attachment of the cariogenic Streptococcus mutans onto dental enamel is largely promoted by the adsorption of specific salivary proteins on enamel surface. Some phosphorylated salivary proteins were found to reduce S. mutans adhesion by competitively inhibiting the adsorption of S. mutans-binding salivary glycoproteins to hydroxyapatite (HA). The aim of this study was to develop antiadherence compounds for preventing dental biofilm development. We synthesized phosphorylated polyethylene glycol (PEG) derivatives and examined the possibility of surface pretreatment with them for preventing S. mutans adhesion in vitro and dental biofilm formation in vivo. Pretreatment of the HA surface with methacryloyloxydecyl phosphate (MDP)-PEG prior to saliva incubation hydrophilized the surface and thereby reduced salivary protein adsorption and saliva-promoted bacterial attachment to HA. However, when MDP-PEG was added to the saliva-pretreated HA (S-HA) surface, its inhibitory effect on bacterial binding was completely diminished. S. mutans adhesion onto S-HA was successfully reduced by treatment of the surface with pyrophosphate (PP), which desorbs salivary components from S-HA. Treatment of S-HA surfaces with MDP-PEG plus PP completely inhibited saliva-promoted S. mutans adhesion even when followed by additional saliva treatment. Finally, mouthwash with MDP-PEG plus PP prevented de novo biofilm development after thorough teeth cleaning in humans compared to either water or PP alone. We conclude that MDP-PEG plus PP has the potential for use as an antiadherence agent that prevents dental biofilm development.

  16. Concentration of seeded simian rotavirus SA-11 from potable waters by using talc-celite layers and hydroextraction.

    PubMed

    Ramia, S; Sattar, S A

    1980-03-01

    There is mounting evidence for the waterborne transmission of diarrhea caused by rotaviruses. As a result, proper techniques are required for their recovery from samples of incriminated water. The combined efficiency of the talc-Celite technique and polyethylene glycol 6000 hydroextraction was, therefore, tested for this purpose, using Simian rotavirus SA-11 and MA-104 cells. Conditioning of the dechlorinated tap water samples was carried out by pH adjustment to 6.0 and the addition of Earle balanced salt solution to a final concentration of 1:100. Passage of a 1-liter volume of such a conditioned sample through a layer containing a mixture of talc (300 mg) and Celite 503 (100 mg) led to the adsorption of nearly 93% of the added SA-11 plaque-forming units. For the recovery of the layer-adsorbed virus, 3% beef extract and 1x tryptose phosphate broth were found to be superior to a variety of other eluents tested. When we tested 100-liter sample volumes, layers containing 1.2 g of talc and 0.4 g of Celite were employed. Virus elution was carried out with 100 ml of tryptose phosphate broth. The eluate was concentrated 10-fold by overnight (4 degrees C) hydroextraction with polyethylene glycol. With a total input virus of 7.0 x 10(5) and 1.4 x 10(2) plaque-forming units, the recoveries were about 71 and 59%, respectively.

  17. PHENANTHROLINE-STABILIZED PALLADIUM NANOPARTICLES IN POLYETHYLENE GLYCOL—AN ACTIVE AND RECYCLABLE CATALYST SYSTEM FOR THE SELECTIVE HYDROGENATION OF OLEFINS USING MOLECULAR HYDROGEN

    EPA Science Inventory

    1,10-Phenanthroline-stabilized palladium nanoparticles dispersed in a polyethylene glycol (PEG) matrix is synthesized which is found to be a stable and active catalyst for the selective hydrogenation of olefins using molecular hydrogen under mild reaction conditions. A variety of...

  18. Poly(ethylene glycol) analogs grafted with low molecular weight poly(ethylene imine) as non-viral gene vectors.

    PubMed

    Zhang, Zhenfang; Yang, Cuihong; Duan, Yajun; Wang, Yanming; Liu, Jianfeng; Wang, Lianyong; Kong, Deling

    2010-07-01

    A novel class of non-viral gene vectors consisting of low molecular weight poly(ethylene imine) (PEI) (molecular weight 800 Da) grafted onto degradable linear poly(ethylene glycol) (PEG) analogs was synthesized. First, a Michael addition reaction between poly(ethylene glycol) diacrylates (PEGDA) (molecular weight 258 Da) and d,l-dithiothreitol (DTT) was carried out to generate a linear polymer (PEG-DTT) having a terminal thiol, methacrylate and pendant hydroxyl functional groups. Five PEG-DTT analogs were synthesized by varying the molar ratio of diacrylates to thiols from 1.2:1 to 1:1.2. Then PEI (800 Da) was grafted onto the main chain of the PEG-DTTs using 1,1'-carbonyldiimidazole as the linker. The above reaction gave rise to a new class of non-viral gene vectors, (PEG-DTT)-g-PEI copolymers, which can effectively complex DNA to form nanoparticles. The molecular weights and structures of the copolymers were characterized by gel permeation chromatography, (1)H nuclear magnetic resonance and Fourier transform infrared spectroscopy. The size of the nanoparticles was<200 nm and the surface charge of the nanoparticles, expressed as the zeta potential, was between+20 and+40 mV. Cytotoxicity assays showed that the copolymers exhibited much lower cytotoxicities than high molecular weight PEI (25 kDa). Transfection was performed in cultured HeLa, HepG2, MCF-7 and COS-7 cells. The copolymers showed higher transfection efficiencies than PEI (25 kDa) tested in four cell lines. The presence of serum (up to 30%) had no inhibitory effect on the transfection efficiency. These results indicate that this new class of non-viral gene vectors may be a promising gene carrier that is worth further investigation. Copyright 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  19. Preparation of Single-Stranded Bacteriophage M13 DNA by Precipitation with Polyethylene Glycol.

    PubMed

    Green, Michael R; Sambrook, Joseph

    2017-11-01

    Bacteriophage M13 single-stranded DNA is prepared from virus particles secreted by infected bacteria into the surrounding medium. Several methods are available to purify the polymorphic filamentous particles. In this protocol, the particles are concentrated by precipitation with polyethylene glycol (PEG) in the presence of high salt. Subsequent extraction with phenol releases the single-stranded DNA, which is then collected by precipitation with ethanol. The resulting preparation is pure enough to be used as a template for DNA sequencing. A yield of 5-10 µg of single-stranded DNA/mL of infected cells may be expected from recombinant bacteriophages bearing inserts of 300-1000 nt. © 2017 Cold Spring Harbor Laboratory Press.

  20. Optical emission spectroscopy as a tool for the biodistribution investigation of cobalt-ferrite nanoparticles in mice

    NASA Astrophysics Data System (ADS)

    Kückelhaus, S.; Tedesco, A. C.; Oliveira, D. M.; Morais, P. C.; Boaventura, G. R.; Lacava, Z. G. M.

    2005-05-01

    This study reports on the biodistribution investigation of two magnetic samples both based on cobalt-ferrite nanoparticles, a magnetic fluid sample (CoMF) and a stealth magnetoliposome polyethylene glycol-monolaurate (PEG-ML). Morphology observations and iron and cobalt concentrations were evaluated after treatment of mice upon intravenous injection. Both magnetic samples had an extended distribution throughout all investigated organs. CoMF was quickly eliminated mainly by the fecal via whereas PEG-ML was retained longer in the circulation and slowly eliminated. These differences are probably due to the presence of polyethylene glycol on the PEG-ML surface, recognized to be responsible for the internalization delay of nanoparticles.

  1. Poly(ethylene glycol)-[60]Fullerene-Based Materials for Perovskite Solar Cells with Improved Moisture Resistance and Reduced Hysteresis.

    PubMed

    Collavini, Silvia; Saliba, Michael; Tress, Wolfgang R; Holzhey, Philippe J; Völker, Sebastian F; Domanski, Konrad; Turren-Cruz, Silver H; Ummadisingu, Amita; Zakeeruddin, Shaik M; Hagfeldt, Anders; Grätzel, Michael; Delgado, Juan L

    2018-03-22

    A series of [60]fullerenes covalently functionalized with the polymer poly(ethylene glycol) is presented. These new [60]fullerene-based materials have been incorporated as additives in CH 3 NH 3 PbI 3 (MAPbI 3 ), the most common organic-inorganic perovskite used in perovskite solar cells. The extensive photovoltaic study performed by using these materials shows several beneficial effects on the performance of these cells, including a reduction in hysteresis and an increased stability against moisture, whereby the solar cells retain up to 97 % of their initial power conversion efficiency in an ambient atmosphere. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Allergic reaction to polyethylene glycol in a painter.

    PubMed

    Antolin-Amerigo, D; Sánchez-González, M J; Barbarroja-Escudero, J; Rodríguez-Rodríguez, M; Álvarez-Perea, A; Alvarez-Mon, M

    2015-08-01

    We report a case of a male painter who visited our outpatient clinic after developing a distinct skin reaction 15 min after the ingestion of a laxative solution containing polyethylene glycol (PEG) prior to colonoscopy. He described suffering from the same skin reaction when he was previously exposed to paints that contained PEG-4000. An exposure challenge test with pure PEG-4000, simulating his workplace conditions, elicited a generalized urticarial reaction. Allergy to PEG should be considered in painters who develop urticarial or other systemic symptoms after handling PEG-containing products. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Process for recovering pertechnetate ions from an aqueous solution also containing other ions

    DOEpatents

    Rogers, Robin; Horwitz, E. Philip; Bond, Andrew H.

    1997-01-01

    A solid/liquid process for the separation and recovery of TcO.sub.4.sup.-1 ions from an aqueous solution is disclosed. The solid support comprises separation particles having surface-bonded poly(ethylene glycol) groups; whereas the aqueous solution from which the TcO.sub.4.sup.-1 ions are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved salt. A solid/liquid phase admixture of separation particles containing bound TcO.sub.4.sup.-1 ions in such an aqueous solution that is free from MoO.sub.4.sup.-2 ions is also contemplated, as is a chromatography apparatus containing that solid/liquid phase admixture.

  4. Synthesis, characterization and hydrolytic degradation study of polyetheresteramide copolymers based on epsilon-caprolactone, 6-aminocaproic acid, and poly(ethylene glycol).

    PubMed

    Liu, CaiBing; Qian, ZhiYong; Jia, WenJuan; Huang, MeiJuan; Chao, GuoTao; Gong, ChangYang; Deng, HongXin; Wen, YanJun; Yang, JinLiang; Gou, MaLing; Tu, MingJing

    2007-10-01

    In this paper, a new kind of biodegradable aliphatic polyetheresteramide copolymers (PEEA) based on epsilon-caprolactone, 6-aminocaproic acid, and poly(ethylene glycol) (PEG) were synthesized by melt polymerization method. The obtained copolymers were characterized by 1H-NMR. The thermal properties of PEEA copolymers were studied by DSC and TGA/DTA under nitrogen atmosphere. The water absorption and hydrolytic degradation behavior was also studied in detail. With the increase in PEG content or the decrease in caprolactone content, the water absorption of the copolymers increased accordingly. For the hydrolytic degradation behavior, with the increase in PEG content or caprolactone content, the degradation rate increased then.

  5. Effects of Polyethylene Glycol and Citric Acid on Preparation and Hydrodechlorination Activity of Molybdenum Phosphide

    NASA Astrophysics Data System (ADS)

    Liu, Xiaomeng; Lu, Shaoxiang; Xu, Hanghui; Ren, Lili

    2018-07-01

    Molybdenum phosphide (MoP), modified by polyethylene glycol (PEG) and citric acid (CA), exhibited 2 to 3 times superior activity than the MoP modified by CA alone. And the optimal activity temperature was reduced from 500 to 450oC. The catalyst was fully characterized by a variety of techniques including X-ray diffraction (XRD), N2 adsorption-desorption isotherm, scanning electron microscopy (SEM), transmission electron microscopy (TEM). The results showed that the addition of PEG and CA increased the surface area of MoP and decreased the particle size of MoP. Furthermore, the reaction mechanism also has been discussed by combining the activity data and characterization results.

  6. A retention index system for comprehensive two-dimensional gas chromatography using polyethylene glycols.

    PubMed

    Veenaas, Cathrin; Haglund, Peter

    2018-02-09

    The characterization and identification of compounds in complex real-world samples is quite difficult and new concepts and workflows are highly desirable. Retention indices (RIs) are widely used in gas chromatography (GC) to support the identification of unknown compounds. Several attempts have been made to introduce a similar concept for the second dimension in comprehensive two-dimensional (2D) GC (GC × GC) but, an easily applicable and robust system remains elusive. In the present study, a new RI system for GC × GC was developed. Polyethylene glycols (PEGs) were used in combination with a simple linear regression, with n-alkanes as reference points for virtually unretained compounds and PEG homologs as reference compounds for second-dimension RIs (PEG- 2 I). The n-alkanes were assigned a PEG- 2 I of zero and the distance between consecutive PEG homologs from PEG-2 (diethylene glycol) and higher were assigned a PEG- 2 I value of 10. We used ethylene glycol and PEG-2 through PEG-10 as reference compounds, thereby covering a PEG- 2 I range from 20.0 for ethylene glycol, over 50.0 for diethylene glycol (PEG-2) to 130.0 for decaethylene glycol (PEG-10); additional PEGs can be added to cover a wider polarity range. The PEG- 2 I system was initially evaluated using a 30 m × 0.25 mm non-polar (5% phenyl, 0.25 μm film thickness) first-dimension column and a 1.6 m × 0.18 mm polar (50% phenyl, 0.18 μm film thickness) second-dimension column. This system was validated for use with non-polar first-dimension columns and a semi-polar (50% phenyl) second-dimension column, and exhibited robustness to changes in the carrier gas flow velocity, oven temperature ramping rate, and secondary oven temperature offset. An average relative standard deviation of 2.7%, equal to a 95% confidence interval of 1.27 PEG- 2 I units, was obtained for the PEG- 2 I values of 72 environmental pollutants. Additionally, the system was found to be applicable over a wide range of boiling points (in the current case, from n-heptane to n-dotriacontane (C 7 -C 32 )) and can be used with various column dimensions. Changing the second-dimension column to either a narrower 0.1 mm column or a wider 0.25 mm column, yielded similar 95%-percentiles to that of the 0.18 mm column, differing by only 3.20 and 2.80 PEG- 2 I units, respectively. Moreover, methods for improving the system were suggested. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Simultaneous effects of tocopheryl polyethylene glycol succinate (TPGS) on local hair growth promotion and systemic absorption of topically applied minoxidil in a mouse model.

    PubMed

    Chen, Chien-Ho; Sheu, Ming-Thau; Wu, An-Bang; Lin, Keng-Ping; Ho, Hsiu-O

    2005-12-08

    In this study, topical minoxidil solutions supplemented with TPGS in cosolvent systems of various compositions consisting of water, alcohol, and polyethylene glycol 400 were designed to evaluate the efficacy of promoting hair growth after topical application and the safety in terms of the amount of minoxidil absorbed through the skin into the circulation using C57BL/6J mice as a model. The commercial product of 2% Regaine) was used as the positive control. The role, which sulfotransferase activity plays in hair growth with treatment using minoxidil, was determined as well. The results revealed that the addition of 0.5% TPGS was able to enhance the proliferation of hair, but an increase in the amount of TPGS to 2% led to deterioration in the enhancement of hair growth. At the higher added amount (2.0%) of TPGS, the promotion of hair growth was slightly reduced for both cosolvent formulations F1 (100% water) and F3 (100% PEG 400), whereas it was reduced to a greater extent for the cosolvent formulations F8-F10. In comparison, the influences of cosolvent compositions with TPGS amounts of 0.0 and 2.0% on the promotion of hair growth were similar. On the contrary, variability in the promotion of hair growth by different solvent formulations was minimal when the added amount of TPGS was 0.5%. In general, a relationship between hair growth and sulfotransferase activities after topical application of 2% Regaine and minoxidil formulations containing various amounts of TPGS was not demonstrated. Plasma concentrations of minoxidil with 2% Regaine were found to be greater than those of 2% minoxidil in those cosolvent formulations containing various amounts of TPGS, while showing insignificant differences among those 10 cosolvent formulations with a fixed amount of TPGS. A tendency for the plasma concentration of minoxidil to increase after the topical administration of minoxidil formulations containing the higher amount of TPGS (2%) was noted.

  8. Simethicone improves bowel cleansing with low-volume polyethylene glycol: a multicenter randomized trial.

    PubMed

    Zhang, Shenghong; Zheng, Danping; Wang, Jinping; Wu, Jianwei; Lei, Pingguang; Luo, Qi; Wang, Liping; Zhang, Beiping; Wang, Hong; Cui, Yi; Chen, Minhu

    2018-04-01

     For bowel preparation, using a reduced volume of polyethylene glycol (PEG) solution without influencing its effectiveness would be preferable. While simethicone shows great potential as an adjunctive agent, data on its use are limited. We aimed to clarify whether simethicone added to low-volume PEG solution improved bowel cleansing. PATIENTS AND METHODS : Consecutive adult patients registered for colonoscopy were recruited from seven medical centers in South China between 15 April and 15 July 2015 and prospectively randomized into two groups: 2 L PEG (conventional group) and 2 L PEG plus simethicone (simethicone group). The primary endpoint was the effectiveness of bowel cleansing according to the Boston Bowel Preparation Scale (BBPS). Secondary endpoints included cecal intubation time, adenoma detection rate (ADR), patient safety and compliance, and adverse events. RESULTS : We included 290 and 289 patients in the conventional and simethicone groups, respectively, for analysis. The proportion with acceptable bowel cleansing (BBPS ≥ 6) was significantly higher in the simethicone group than in the conventional group (88.2 % vs. 76.6 %; P  < 0.001). The mean (SD) BBPS score was significantly lower in the conventional group (6.5 [1.8] vs. 7.3 [1.7]; P  < 0.001), as was the bubble score (2.5 [0.7] vs. 2.8 [0.5]; P  < 0.001). The average cecal intubation time was significantly shorter in the simethicone group (6.3 [3.1] vs. 7.5 [5.1] minutes; P  < 0.001). The ADR in the right colon was higher in the simethicone group than in the conventional group (16.6 % vs. 10.3 %; P  = 0.03). Safety and compliance, including the taste, smell, and dosage of PEG, were similar for both groups.  Simethicone added to low-volume PEG solution improves bowel-cleansing efficacy, with similar safety and compliance, shorter cecal intubation time, and higher ADR. © Georg Thieme Verlag KG Stuttgart · New York.

  9. Influence of different surfactants on the physicochemical properties of elastic liposomes.

    PubMed

    Barbosa, R M; Severino, P; Preté, P S C; Santana, M H A

    2017-05-01

    Elastic liposomes are capable to improve drug transport through the skin by acting as penetration enhancers due to the high fluidity and elasticity of the liposome membranes. Therefore, elastic liposomes were prepared and characterized to facilitate the transdermal transport of bioactive molecules. Liposomes consisted of dimyristoylphosphatidylcholine (DMPC) as the structural component, with different surfactants derived from lauric acid as elastic components: C 12 E 5 (polyoxyethylene-5-lauryl ether), PEG4L (polyethyleneglycol-4-lauryl ester), PEG4DL (polyethylene glycol-4-dilauryl ester), PEG8L (polyethylene glycol-8-lauryl ester) and PEG8DL (polyethylene glycol-8-dilauryl ester). The elastic liposomes were characterized in terms of their phospholipid content, mean diameter, size distribution, elasticity and stability during storage, as well as their ability to incorporate surfactant and permeate through 50 nm pore size membranes. The results showed that the phospholipid phase transition temperature, the fluidity of the lipid bilayer resulting from incorporation of the surfactant and the preservation of particle integrity were factors determining the performance of the elastic liposomes in permeating through nanoporous membranes. The best results were obtained using DMPC combined with the surfactants PEG8L or PEG8DL. The findings demonstrate the potential of using elastic liposomes for transdermal administration of drugs.

  10. Identification of Poly(ethylene glycol) and Poly(ethylene glycol)-Based Detergents Using Peptide Search Engines.

    PubMed

    Ahmadi, Shiva; Winter, Dominic

    2018-06-05

    Poly(ethylene glycol) (PEG) is one of the most common polymer contaminations in mass spectrometry (MS) samples. At present, the detection of PEG and other polymers relies largely on manual inspection of raw data, which is laborious and frequently difficult due to sample complexity and retention characteristics of polymer species in reversed-phase chromatography. We developed a new strategy for the automated identification of PEG molecules from tandem mass spectrometry (MS/MS) data using protein identification algorithms in combination with a database containing "PEG-proteins". Through definition of variable modifications, we extend the approach for the identification of commonly used PEG-based detergents. We exemplify the identification of different types of polymers by static nanoelectrospray tandem mass spectrometry (nanoESI-MS/MS) analysis of pure detergent solutions and data analysis using Mascot. Analysis of liquid chromatography-tandem mass spectrometry (LC-MS/MS) runs of a PEG-contaminated sample by Mascot identified 806 PEG spectra originating from four PEG species using a defined set of modifications covering PEG and common PEG-based detergents. Further characterization of the sample for unidentified PEG species using error-tolerant and mass-tolerant searches resulted in identification of 3409 and 3187 PEG-related MS/MS spectra, respectively. We further demonstrate the applicability of the strategy for Protein Pilot and MaxQuant.

  11. The behavior of peroxisomes in vitro: mammalian peroxisomes are osmotically sensitive particles.

    PubMed

    Antonenkov, Vasily D; Sormunen, Raija T; Hiltunen, J Kalervo

    2004-12-01

    It has been known for a long time that mammalian peroxisomes are extremely fragile in vitro. Changes in the morphological appearance and leakage of proteins from purified particles demonstrate that peroxisomes are damaged during isolation. However, some properties of purified peroxisomes, e.g., the latency of catalase, imply that their membranes are not disrupted. In the current study, we tried to ascertain the mechanism of this unusual behavior of peroxisomes in vitro. Biochemical and morphological examination of isolated peroxisomes subjected to sonication or to freezing and thawing showed that the membrane of the particles seals after disruption, restoring permeability properties. Transient damage of the membrane leads to the formation of peroxisomal "ghosts" containing nucleoid but nearly devoid of matrix proteins. The rate of leakage of matrix proteins from broken particles depended inversely on their molecular size. The effect of polyethylene glycols on peroxisomal integrity indicated that these particles are osmotically sensitive. Peroxisomes suffered an osmotic lysis during isolation that was resistant to commonly used low-molecular-mass osmoprotectors, e.g., sucrose. Damage to peroxisomes was partially prevented by applying more "bulky" osmoprotectors, e.g., polyethylene glycol 1500. A method was developed for the isolation of highly purified and nearly intact peroxisomes from rat liver by using polyethylene glycol 1500 as an osmoprotector.

  12. Novel pH responsive polymethacrylic acid-chitosan-polyethylene glycol nanoparticles for oral peptide delivery.

    PubMed

    Sajeesh, S; Sharma, Chandra P

    2006-02-01

    In present study, novel pH sensitive polymethacrylic acid-chitosan-polyethylene glycol (PCP) nanoparticles were prepared under mild aqueous conditions via polyelectrolyte complexation. Free radical polymerization of methacrylic acid (MAA) was carried out in presence of chitosan (CS) and polyethylene glycol (PEG) using a water-soluble initiator and particles were obtained spontaneously during polymerization without using organic solvents or surfactants/steric stabilizers. Dried particles were analyzed by scanning electron microscopy (SEM) and particles dispersed in phosphate buffer (pH 7.0) were visualized under transmission electron microscope (TEM). SEM studies indicated that PCP particles have an aggregated and irregular morphology, however, TEM revealed that these aggregated particles were composed of smaller fragments with size less than 1 micron. Insulin and bovine serum albumin (BSA) as model proteins were incorporated into the nanoparticles by diffusion filling method and their in vitro release characteristics were evaluated at pH 1.2 and 7.4. PCP nanoparticles exhibited good protein encapsulation efficiency and pH responsive release profile was observed under in vitro conditions. Trypsin inhibitory effect of these PCP nanoparticles was studied using casein substrate and these particles displayed lesser inhibitory effect than reference polymer carbopol. Preliminary investigation suggests that these particles can serve as good candidate for oral peptide delivery. Copyright 2005 Wiley Periodicals, Inc.

  13. Nanoformulation of D-α-tocopheryl polyethylene glycol 1000 succinate-b-poly(ε-caprolactone-ran-glycolide) diblock copolymer for breast cancer therapy.

    PubMed

    Huang, Laiqiang; Chen, Hongbo; Zheng, Yi; Song, Xiaosong; Liu, Ranyi; Liu, Kexin; Zeng, Xiaowei; Mei, Lin

    2011-10-01

    The purpose of this research was to develop formulation of docetaxel-loaded biodegradable TPGS-b-(PCL-ran-PGA) nanoparticles for breast cancer chemotherapy. A novel diblock copolymer, d-α-tocopheryl polyethylene glycol 1000 succinate-b-poly(ε-caprolactone-ran-glycolide) [TPGS-b-(PCL-ran-PGA)], was synthesized from ε-caprolactone, glycolide and d-α-tocopheryl polyethylene glycol 1000 succinate by ring-opening polymerization using stannous octoate as catalyst. The obtained copolymers were characterized by (1)H NMR, GPC and TGA. The docetaxel-loaded TPGS-b-(PCL-ran-PGA) nanoparticles were prepared and characterized. The data showed that the fluorescence TPGS-b-(PCL-ran-PGA) nanoparticles could be internalized by MCF-7 cells. The TPGS-b-(PCL-ran-PGA) nanoparticles achieved significantly higher level of cytotoxicity than commercial Taxotere®. MCF-7 xenograft tumor model on SCID mice showed that docetaxel formulated in the TPGS-b-(PCL-ran-PGA) nanoparticles could effectively inhibit the growth of tumor over a longer period of time than Taxotere® at the same dose. In conclusion, the TPGS-b-(PCL-ran-PGA) copolymer could be acted as a novel and potential biologically active polymeric material for nanoformulation in breast cancer chemotherapy. This journal is © The Royal Society of Chemistry 2011

  14. Facile synthesis of thiol-polyethylene glycol functionalized magnetic titania nanomaterials for highly efficient enrichment of N-linked glycopeptides.

    PubMed

    Wang, Jiawen; Yao, Jizong; Sun, Nianrong; Deng, Chunhui

    2017-08-25

    As protein N-glycosylation involved in generation and development of various cancers and diseases, it is vital to capture glycopeptides from complex biological samples for biomarker discovery. In this work, by taking advantages of the interaction between titania and thiol groups, thiol-polyethylene glycol functionalized magnetic titania nanomaterials (denoted as Fe 3 O 4 @TiO 2 @PEG) were firstly fabricated as an excellent hydrophilic adsorbent of N-linked glycopeptides. On one hand, the special interaction of titanium-thiol makes the synthetic manipulation simple and provides a new idea for design and synthesis of novel nanomaterials; on the other hand, strong magnetic response could realize rapid separation and the outstanding hydrophilicity of polyethylene glycol makes Fe 3 O 4 @TiO 2 @PEG nanomaterials show superior performance for glycopeptides enrichment with ultralow limit of detection (0.1mol/μL) and high selectivity (1:100). As a result, 24 and 33 glycopeptides enriched from HRP and IgG digests were identified respectively by MALDI-TOF MS, and 300 glycopeptides corresponding to 106 glycoproteins were recognized from merely 2μL human serum, indicating a great potential of Fe 3 O 4 @TiO 2 @PEG nanomaterials for glycoproteomic research. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Effect of polyethylene glycol 4000 supplementation on the performance of yearling male Pedi goats fed dietary mixture levels of Acacia karroo leaf meal and Setaria verticillata grass hay.

    PubMed

    Brown, David; Ng'ambi, Jones W

    2017-06-01

    Eighteen yearling male Pedi goats weighing 21.7 ± 3.1 kg were used in a 42-day trial in a 2 (Acacia karroo leaf meal levels) × 3 (levels of PEG 4000) factorial arrangement in a completely randomized design to determine PEG 4000 supplementation levels for optimal productivity of indigenous Pedi goats fed different mixture levels of A. karroo leaf meal and Setaria verticillata (L.) P.Beauv. grass hay. Each goat was supplemented with 0, 23 or 30 g of PEG 4000 per day in addition to dietary mixture of A. karroo and S. verticillata hay. Polyethylene glycol 4000 supplementation had no effect (P > 0.05) on nutrient intake of goats. However, a diet × PEG (P < 0.05) was observed for intake of all nutrients studied. Dry matter, OM, NDF and ADF intakes per goat were optimized at PEG 4000 supplementation levels of 19.62, 19.62, 19.61 and 19.53 g/goat/day, respectively, for diets containing 20% A. karroo leaf meal. Polyethylene glycol 4000 supplementation had no effect (P > 0.05) on the apparent digestibility of all nutrients. The dietary inclusion level of A. karroo leaf meal at 20% improved (P < 0.05) DM, OM, CP, NDF and ADF digestibility of goats. Crude protein digestibility was optimized at a PEG 4000 supplementation level of 15.78 g/goat/day. Dietary mixture level and PEG 4000 supplementation had no effect (P > 0.05) on final weights of Pedi goats. Similar results were observed for blood urea and glucose concentrations of yearling male Pedi goats. However, daily body weight gain was higher (P < 0.05) in goats fed 50% A. karroo leaf meal than those on 20% inclusion level. Polyethylene glycol 4000 has potential to improve the feeding value of tanninifeorus A. karroo leaf meal.

  16. Boron-based nanostructures: Synthesis, functionalization, and characterization

    NASA Astrophysics Data System (ADS)

    Bedasso, Eyrusalam Kifyalew

    Boron-based nanostructures have not been explored in detail; however, these structures have the potential to revolutionize many fields including electronics and biomedicine. The research discussed in this dissertation focuses on synthesis, functionalization, and characterization of boron-based zero-dimensional nanostructures (core/shell and nanoparticles) and one-dimensional nanostructures (nanorods). The first project investigates the synthesis and functionalization of boron-based core/shell nanoparticles. Two boron-containing core/shell nanoparticles, namely boron/iron oxide and boron/silica, were synthesized. Initially, boron nanoparticles with a diameter between 10-100 nm were prepared by decomposition of nido-decaborane (B10H14) followed by formation of a core/shell structure. The core/shell structures were prepared using the appropriate precursor, iron source and silica source, for the shell in the presence of boron nanoparticles. The formation of core/shell nanostructures was confirmed using high resolution TEM. Then, the core/shell nanoparticles underwent a surface modification. Boron/iron oxide core/shell nanoparticles were functionalized with oleic acid, citric acid, amine-terminated polyethylene glycol, folic acid, and dopamine, and boron/silica core/shell nanoparticles were modified with 3-(amino propyl) triethoxy silane, 3-(2-aminoethyleamino)propyltrimethoxysilane), citric acid, folic acid, amine-terminated polyethylene glycol, and O-(2-Carboxyethyl)polyethylene glycol. A UV-Vis and ATR-FTIR analysis established the success of surface modification. The cytotoxicity of water-soluble core/shell nanoparticles was studied in triple negative breast cancer cell line MDA-MB-231 and the result showed the compounds are not toxic. The second project highlights optimization of reaction conditions for the synthesis of boron nanorods. This synthesis, done via reduction of boron oxide with molten lithium, was studied to produce boron nanorods without any contamination and with a uniform size distribution. Various reaction parameters such as temperature, reaction time, and sonication were altered to find the optimal reaction conditions. Once these conditions were determined, boron nanorods were produced then functionalized with amine-terminated polyethylene glycol.

  17. Minocycline enhances the mesenchymal stromal/stem cell pro-healing phenotype in triple antimicrobial-loaded hydrogels.

    PubMed

    Guerra, Alberto Daniel; Rose, Warren E; Hematti, Peiman; Kao, W John

    2017-03-15

    Mesenchymal stromal/stem cells (MSCs) have demonstrated pro-healing properties including an anti-inflammatory cytokine profile and the promotion of angiogenesis via expression of growth factors in pre-clinical models. MSCs encapsulated in poly(ethylene glycol) diacrylate (PEGdA) and thiolated gelatin poly(ethylene glycol) (Gel-PEG-Cys) crosslinked hydrogels have led to controlled cellular presentation at wound sites with favorable wound healing outcomes. However, the therapeutic potential of MSC-loaded hydrogels may be limited by non-specific protein adsorption on the delivery matrix that could facilitate the initial adhesion of microorganisms and subsequent virulent biofilm formation. Antimicrobials loaded concurrently in the hydrogels with MSCs could reduce microbial bioburden and promote healing, but the antimicrobial effect on the MSC wound healing capacity and the antibacterial efficacy of the hydrogels is unknown. We demonstrate that minocycline specifically induces a favorable change in MSC migration capacity, proliferation, gene expression, extracellular matrix (ECM) attachment, and adhesion molecule and growth factor release with subsequent increased angiogenesis. We then demonstrate that hydrogels loaded with MSCs, minocycline, vancomycin, and linezolid can significantly decrease bacterial bioburden. Our study suggests that minocycline can serve as a dual mechanism for the regenerative capacity of MSCs and the reduction of bioburden in triple antimicrobial-loaded hydrogels. Wound healing is a complex biological process that can be hindered by bacterial infection, excessive inflammation, and inadequate microvasculature. In this study, we develop a new formulation of poly(ethylene glycol) diacrylate and thiolated gelatin poly(ethylene glycol) crosslinked hydrogels loaded with minocycline, vancomycin, linezolid, and mesenchymal stromal/stem cells that induces a favorable wound healing phenotype in mesenchymal stromal/stem cells and prevents bacterial bioburden on the hydrogel. This combinatorial approach to biomaterial development has the potential to impact wound healing for contaminated full thickness cutaneous wounds. Copyright © 2017. Published by Elsevier Ltd.

  18. Effect of solubilizing agents on mupirocin loading into and release from PEGylated nanoliposomes.

    PubMed

    Cern, Ahuva; Nativ-Roth, Einat; Goldblum, Amiram; Barenholz, Yechezkel

    2014-07-01

    Mupirocin was identified by quantitative structure property relationship models as a good candidate for remote liposomal loading. Mupirocin is an antibiotic that is currently restricted to topical administration because of rapid hydrolysis in vivo to its inactive metabolite. Formulating mupirocin in PEGylated nanoliposomes may potentially expand its use to parenteral administration by protecting it from degradation in the circulation and target it (by the enhanced permeability effect) to the infected tissue. Mupirocin is slightly soluble in aqueous medium and its solubility can be increased using solubilizing agents. The effect of the solubilizing agents on mupirocin remote loading was studied when the solubilizing agents were added to the drug loading solution. Propylene glycol was found to increase mupirocin loading, whereas polyethylene glycol 400 showed no effect. Hydroxypropyl-β-cyclodextrin (HPCD) showed a concentration-dependent effect on mupirocin loading; using the optimal HPCD concentration increased loading, but higher concentrations inhibited it. The inclusion of HPCD in the liposome aqueous phase while forming the liposomes resulted in increased drug loading and substantially inhibited drug release in serum. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  19. 21 CFR 178.3750 - Polyethylene glycol (mean molecular weight 200-9,500).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... conditions: (a) The additive is an addition polymer of ethylene oxide and water with a mean molecular weight of 200 to 9,500. (b) It contains no more than 0.2 percent total by weight of ethylene and diethylene... ethylene and diethylene glycols if its mean molecular weight is below 350, when tested by the analytical...

  20. Biodegradable mucus-penetrating nanoparticles composed of diblock copolymers of polyethylene glycol and poly(lactic-co-glycolic acid)

    PubMed Central

    Yu, Tao; Wang, Ying-Ying; Yang, Ming; Schneider, Craig; Zhong, Weixi; Pulicare, Sarah; Choi, Woo-Jin; Mert, Olcay; Fu, Jie; Lai, Samuel K.; Hanes, Justin

    2013-01-01

    Mucus secretions coating entry points to the human body that are not covered by skin efficiently trap and clear conventional drug carriers, limiting controlled drug delivery at mucosal surfaces. To overcome this challenge, we recently engineered nanoparticles that readily penetrate a variety of human mucus secretions, which we termed mucus-penetrating particles (MPP). Here, we report a new biodegradable MPP formulation based on diblock copolymers of poly(lactic-co-glycolic acid) and poly(ethylene glycol) (PLGA-PEG). PLGA-PEG nanoparticles prepared by a solvent diffusion method rapidly diffused through fresh, undiluted human cervicovaginal mucus (CVM) with an average speed only eightfold lower than their theoretical speed in water. In contrast, PLGA nanoparticles were slowed more than 12,000-fold in the same CVM secretions. Based on the measured diffusivities, as much as 75% of the PLGA-PEG nanoparticles are expected to penetrate a 10-μm-thick mucus layer within 30 min, whereas virtually no PLGA nanoparticles are expected to do so over the same duration. These results encourage further development of PLGA-PEG nanoparticles as mucus-penetrating drug carriers for improved drug and gene delivery to mucosal surfaces. PMID:24205449

  1. Poly(ethylene glycol)-based ionic liquids: properties and uses as alternative solvents in organic synthesis and catalysis.

    PubMed

    Cecchini, Martina Maya; Charnay, Clarence; De Angelis, Francesco; Lamaty, Frédéric; Martinez, Jean; Colacino, Evelina

    2014-01-01

    PEG-based ionic liquids are a new appealing group of solvents making the link between two distinct but very similar fluids: ionic liquids and poly(ethylene glycol)s. They find applications across a range of innumerable disciplines in science, technology, and engineering. In the last years, the possibility to use these as alternative solvents for organic synthesis and catalysis has been increasingly explored. This Review highlights strategies for their synthesis, their physical properties (critical point, glass transition temperature, density, rheological properties), and their application in reactions catalyzed by metals (such as Pd, Cu, W, or Rh) or as organic solvent (for example for multicomponent reactions, organocatalysis, CO2 transformation) with special emphasis on their toxicity, environmental impact, and biodegradability. These aspects, very often neglected, need to be considered in addition to the green criteria usually considered to establish ecofriendly processes. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Immobilization of yeast cells with ionic hydrogel carriers by adhesion-multiplication.

    PubMed

    Zhaoxin, L; Fujimura, T

    2000-12-01

    The mixture of an ionic monomer, 2-acrylamido 2-methylpropanesulfonic acid (TBAS), and a series of poly(ethylene glycol) dimethacrylate (nG) monomers were copolymerized with 60Co gamma-rays, and the produced ionic hydrogel polymers were used for immobilization of yeast cells. The cells were adhered onto the surface of the hydrogel polymers and intruded into the interior of the polymers with growing. The immobilized yeast cells with these hydrogel polymers had higher ethanol productivity than that of free cells. The yield of ethanol with poly(TBAS-14G) carrier was the highest and increased by 3.5 times compared to the free cells. It was found that the ethanol yield increased with the increase of glycol number in poly(ethylene glycol) dimethacrylate. The state of the immobilized cells was observed with microscope, and it was also found that the difference in the ethanol productivity is mainly due to the difference in the internal structure and properties of polymer carrier, such as surface charge, hydrophilicity, and swelling ability of polymer carrier.

  3. Bolstering Components of the Immune Response Compromised by Prior Exposure to Adenovirus: Guided Formulation Development for a Nasal Ebola Vaccine

    PubMed Central

    2014-01-01

    The severity and longevity of the current Ebola outbreak highlight the need for a fast-acting yet long-lasting vaccine for at-risk populations (medical personnel and rural villagers) where repeated prime-boost regimens are not feasible. While recombinant adenovirus (rAd)-based vaccines have conferred full protection against multiple strains of Ebola after a single immunization, their efficacy is impaired by pre-existing immunity (PEI) to adenovirus. To address this important issue, a panel of formulations was evaluated by an in vitro assay for their ability to protect rAd from neutralization. An amphiphilic polymer (F16, FW ∼39,000) significantly improved transgene expression in the presence of anti-Ad neutralizing antibodies (NAB) at concentrations of 5 times the 50% neutralizing dose (ND50). In vivo performance of rAd in F16 was compared with unformulated virus, virus modified with poly(ethylene) glycol (PEG), and virus incorporated into poly(lactic-co-glycolic) acid (PLGA) polymeric beads. Histochemical analysis of lung tissue revealed that F16 promoted strong levels of transgene expression in naive mice and those that were exposed to adenovirus in the nasal cavity 28 days prior to immunization. Multiparameter flow cytometry revealed that F16 induced significantly more polyfunctional antigen-specific CD8+ T cells simultaneously producing IFN-γ, IL-2, and TNF-α than other test formulations. These effects were not compromised by PEI. Data from formulations that provided partial protection from challenge consistently identified specific immunological requirements necessary for protection. This approach may be useful for development of formulations for other vaccine platforms that also employ ubiquitous pathogens as carriers like the influenza virus. PMID:25549696

  4. Hyperbranched PEGmethacrylate linear pDMAEMA block copolymer as an efficient non-viral gene delivery vector.

    PubMed

    Mathew, Asha; Cao, Hongliang; Collin, Estelle; Wang, Wenxin; Pandit, Abhay

    2012-09-15

    A unique hyperbranched polymeric system with a linear poly-2-dimethylaminoethyl methacrylate (pDMAEMA) block and a hyperbranched polyethylene glycol methyl ether methacrylate (PEGMEMA) and ethylene dimethacrylate (EGDMA) block was designed and synthesized via deactivation enhanced atom transfer radical polymerisation (DE-ATRP) for efficient gene delivery. Using this unique structure, with a linear pDMAEMA block, which efficiently binds to plasmid DNA (pDNA) and hyperbranched polyethylene glycol (PEG) based block as a protective shell, we were able to maintain high transfection levels without sacrificing cellular viability even at high doses. The transfection capability and cytotoxicity of the polymers over a range of pDNA concentration were analysed and the results were compared to commercially available transfection vectors such as polyethylene imine (branched PEI, 25 kDa), partially degraded poly(amido amine)dendrimer (dPAMAM; commercial name: SuperFect(®)) in fibroblasts and adipose tissue derived stem cells (ADSCs). Copyright © 2012 Elsevier B.V. All rights reserved.

  5. The effect of EGDMA on tensile and thermal properties of irradiated low density polyethylene/sepiolite nanocomposites

    NASA Astrophysics Data System (ADS)

    Ghazali, Siti Nadia Aini; Mohamad, Zurina; Majid, Rohah A.; Appadu, Sivanesan

    2017-07-01

    This study presents the influence of ethylene glycol dimethacrylate (EGDMA) as a crosslinking agent through electron beam crosslinking process. Therefore, the effects of EGDMA on irradiated low density polyethylene/sepiolite (LDPE/SEP) nanocomposites on the tensile and thermal properties at 4 part per hundred resin (phr) sepiolite were investigated. The LDPE/SEP nanocomposites were prepared by melt mixing using twin screw extruder at 160 ˚C with a screw speed of 50 rpm. The nanocomposites were then undergone injection moulding process followed by irradiated using 2 MeV electron beam machine at doses ranging from 0 to 200 kGy in the air at ambient temperature. It was found that the tensile strength and Young's modulus were slightly increased with the presence of co-agent. The sample containing 4 phr sepiolite at 200 kGy showed 9% increase in tensile strength when EGDMA was added. However, the result of thermogravimetry analysis (TGA) showed some reduction in thermal stability of nanocomposites on 100 kGy irradiation dose. EGDMA had reduced the optimum irradiation dose without having any adverse effect on tensile and thermal properties.

  6. Long-term efficacy of polyethylene glycol 3350 for the treatment of chronic constipation in children with and without encopresis.

    PubMed

    Pashankar, Dinesh S; Bishop, Warren P; Loening-Baucke, Vera

    2003-01-01

    Seventy-four children (43 with chronic constipation, 31 with constipation and encopresis) treated with polyethylene glycol 3350 (PEG) for longer than 3 months were studied to assess long-term efficacy. The mean duration of PEG therapy was 8.4 months (range, 3-30). Weekly stool frequency, stool consistency, and symptoms associated with constipation improved significantly with PEG therapy in all 74 patients. In 31 children with encopresis, soiling ceased completely in 16 patients and frequency of soiling decreased significantly in all others. The average effective long-term dose of PEG was 0.7 g/kg/day. Long-term PEG therapy is effective for the treatment of chronic constipation with and without encopresis in children.

  7. Insertion Testing of Polyethylene Glycol Microneedle Array into Cultured Human Skin with Biaxial Tension

    NASA Astrophysics Data System (ADS)

    Takano, Naoki; Tachikawa, Hiroto; Miyano, Takaya; Nishiyabu, Kazuaki

    Aiming at the practical use of polyethylene glycol (PEG) microneedles for transdermal drug delivery system (DDS), a testing apparatus for their insertion into cultured human skin has been developed. To simulate the variety of conditions of human skin, biaxial tension can be applied to the cultured human skin. An adopted testing scheme to apply and control the biaxial tension is similar to the deep-draw forming technique. An attention was also paid to the short-time setup of small, thin and wet cultured skin. One dimensional array with four needles was inserted and influence of tension was discussed. It was found that tension, deflection of skin during insertion and original curvature of skin are the important parameters for microneedles array design.

  8. Preparative purification of polyethylene glycol derivatives with polystyrene-divinylbenzene beads as chromatographic packing.

    PubMed

    Yu, Pengzhan; Li, Xingqi; Li, Xiunan; Lu, Xiuling; Ma, Guanghui; Su, Zhiguo

    2007-10-15

    A clear and powerful chromatographic approach to purify polyethylene glycol derivatives at a preparative scale was reported, which was based on the polystyrene-divinylbenzene beads with ethanol/water as eluants. The validity of this method was verified with the reaction mixture of mPEG-Glu and mPEG propionaldehyde diethylacetal (ALD-PEG) as the model. The target products were one-step achieved with the purity of >99% on the polymer resins column at gram scale. The method developed was free from such disadvantages as utility of toxic solvent and narrow application scope, which was combined with conventional approaches. The method developed provided an appealing and attractive alternative methods for purification of PEG derivatives at a preparative scale.

  9. Water and UV degradable lactic acid polymers

    DOEpatents

    Bonsignore, Patrick V.; Coleman, Robert D.

    1996-01-01

    A water and UV light degradable copolymer of monomers of lactic acid and a modifying monomer selected from the class consisting of ethylene glycol, propylene glycol, P-dioxanone, 1,5 dioxepan-2-one, 1,4-oxathialan-2-one, 1,4-dioxide and mixtures thereof. These copolymers are useful for waste disposal and agricultural purposes. Also disclosed is a water degradable blend of polylactic acid or modified polylactic acid and high molecular weight polyethylene oxide wherein the high molecular weight polyethylene oxide is present in the range of from about 2 by weight to about 50% by weight, suitable for films. A method of applying an active material selected from the class of seeds, seedlings, pesticides, herbicides, fertilizers and mixtures thereof to an agricultural site is also disclosed.

  10. Process for recovering pertechnetate ions from an aqueous solution also containing other ions

    DOEpatents

    Rogers, R.; Horwitz, E.P.; Bond, A.H.

    1997-02-18

    A solid/liquid process for the separation and recovery of TcO{sub 4}{sup {minus}1} ions from an aqueous solution is disclosed. The solid support comprises separation particles having surface-bonded poly(ethylene glycol) groups; whereas the aqueous solution from which the TcO{sub 4}{sup {minus}1} ions are separated contains a poly(ethylene glycol) liquid/liquid biphase-forming amount of a dissolved salt. A solid/liquid phase admixture of separation particles containing bound TcO{sub 4}{sup {minus}1} ions in such an aqueous solution that is free from MoO{sub 4}{sup {minus}2} ions is also contemplated, as is a chromatography apparatus containing that solid/liquid phase admixture. 15 figs.

  11. Thiolated polyethylene oxide as a non-fouling element for nano-patterned bio-devices

    NASA Astrophysics Data System (ADS)

    Lisboa, Patrícia; Valsesia, Andrea; Colpo, Pascal; Gilliland, Douglas; Ceccone, Giacomo; Papadopoulou-Bouraoui, Andri; Rauscher, Hubert; Reniero, Fabiano; Guillou, Claude; Rossi, François

    2007-03-01

    This work describes the synthesis of a thiolated polyethylene oxide that self-assembles on gold to create a non-fouling surface. Thiolated polyethylene oxide was synthesised by reacting 16-mercaptohexadecanoic acid with polyethylene glycol mono methyl ether. The coverage of the thiolated polyethylene oxide on gold was studied by cyclic voltammetry, and the modified surfaces were characterised by X-ray photoelectron spectroscopy and ellipsometry. Protein resistance was assessed using quartz crystal microbalance. Results showed a non-fouling character produced by the thiolated polyethylene oxide. The synthesised product was used as the passivation layer on nano-patterned surfaces consisting of arrayed nano-spots, fabricated by plasma based colloidal lithography. The specific adsorption of anti-bovine serum albumin in the mercaptohexadecanoic acid spots was verified by atomic force microscopy.

  12. Gold nanorod linking to control plasmonic properties in solution and polymer nanocomposites.

    PubMed

    Ferrier, Robert C; Lee, Hyun-Su; Hore, Michael J A; Caporizzo, Matthew; Eckmann, David M; Composto, Russell J

    2014-02-25

    A novel, solution-based method is presented to prepare bifunctional gold nanorods (B-NRs), assemble B-NRs end-to-end in various solvents, and disperse linked B-NRs in a polymer matrix. The B-NRs have poly(ethylene glycol) grafted along its long axis and cysteine adsorbed to its ends. By controlling cysteine coverage, bifunctional ligands or polymer can be end-grafted to the AuNRs. Here, two dithiol ligands (C6DT and C9DT) are used to link the B-NRs in organic solvents. With increasing incubation time, the nanorod chain length increases linearly as the longitudinal surface plasmon resonance shifts toward lower adsorption wavelengths (i.e., red shift). Analogous to step-growth polymerization, the polydispersity in chain length also increases. Upon adding poly(ethylene glycol) or poly(methyl methacrylate) to chloroform solution with linked B-NR, the nanorod chains are shown to retain end-to-end linking upon spin-casting into PEO or PMMA films. Using quartz crystal microbalance with dissipation (QCM-D), the mechanism of nanorod linking is investigated on planar gold surfaces. At submonolayer coverage of cysteine, C6DT molecules can insert between cysteines and reach an areal density of 3.4 molecules per nm(2). To mimic the linking of Au NRs, this planar surface is exposed to cysteine-coated Au nanoparticles, which graft at 7 NPs per μm(2). This solution-based method to prepare, assemble, and disperse Au nanorods is applicable to other nanorod systems (e.g., CdSe) and presents a new strategy to assemble anisotropic particles in organic solvents and polymer coatings.

  13. Gold Nanorod Linking to Control Plasmonic Properties in Solution and Polymer Nanocomposites

    PubMed Central

    2015-01-01

    A novel, solution-based method is presented to prepare bifunctional gold nanorods (B-NRs), assemble B-NRs end-to-end in various solvents, and disperse linked B-NRs in a polymer matrix. The B-NRs have poly(ethylene glycol) grafted along its long axis and cysteine adsorbed to its ends. By controlling cysteine coverage, bifunctional ligands or polymer can be end-grafted to the AuNRs. Here, two dithiol ligands (C6DT and C9DT) are used to link the B-NRs in organic solvents. With increasing incubation time, the nanorod chain length increases linearly as the longitudinal surface plasmon resonance shifts toward lower adsorption wavelengths (i.e., red shift). Analogous to step-growth polymerization, the polydispersity in chain length also increases. Upon adding poly(ethylene glycol) or poly(methyl methacrylate) to chloroform solution with linked B-NR, the nanorod chains are shown to retain end-to-end linking upon spin-casting into PEO or PMMA films. Using quartz crystal microbalance with dissipation (QCM-D), the mechanism of nanorod linking is investigated on planar gold surfaces. At submonolayer coverage of cysteine, C6DT molecules can insert between cysteines and reach an areal density of 3.4 molecules per nm2. To mimic the linking of Au NRs, this planar surface is exposed to cysteine-coated Au nanoparticles, which graft at 7 NPs per μm2. This solution-based method to prepare, assemble, and disperse Au nanorods is applicable to other nanorod systems (e.g., CdSe) and presents a new strategy to assemble anisotropic particles in organic solvents and polymer coatings. PMID:24483622

  14. The effect of the processing and formulation parameters on the size of nanoparticles based on block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide) with and without hydrolytically sensitive groups.

    PubMed

    Neradovic, D; Soga, O; Van Nostrum, C F; Hennink, W E

    2004-05-01

    Block copolymers of poly(ethylene glycol) (PEG) as a hydrophilic block and N-isopropylacrylamide (PNIPAAm) or poly (NIPAAm-co-N-(2-hydroxypropyl) methacrylamide-dilactate) (poly(NIPAAm-co-HPMAm-dilactate)) as a thermosensitive block, are able to self-assemble in water into nanoparticles above the cloud point (CP) of the thermosensitive block. The influence of processing and the formulation parameters on the size of the nanoparticles was studied using dynamic light scattering. PNIPAAm-b-PEG 2000 polymers were not suitable for the formation of small and stable particles. Block copolymers with PEG 5000 and 10000 formed relatively small and stable particles in aqueous solutions at temperatures above the CP of the thermosensitive block. Their size decreased with increasing molecular weight of the thermosensitive block, decreasing polymer concentration and using water instead of phosphate buffered saline as solvent. Extrusion and ultrasonication were inefficient methods to size down the polymeric nanoparticles. The heating rate of the polymer solutions was a dominant factor for the size of the nanoparticles. When an aqueous polymer solution was slowly heated through the CP, rather large particles (> or = 200 nm) were formed. Regardless the polymer composition, small nanoparticles (50-70 nm) with a narrow size distribution were formed, when a small volume of an aqueous polymer solution below the CP was added to a large volume of heated water. In this way the thermosensitive block copolymers rapidly pass their CP ('heat shock' procedure), resulting in small and stable nanoparticles.

  15. Preparation and therapeutic evaluation of (188)Re-thermogelling emulsion in rat model of hepatocellular carcinoma.

    PubMed

    Shih, Ying-Hsia; Lin, Xi-Zhang; Yeh, Chung-Hsin; Peng, Cheng-Liang; Shieh, Ming-Jium; Lin, Wuu-Jyh; Luo, Tsai-Yueh

    2014-01-01

    Radiolabeled Lipiodol(®) (Guerbet, Villepinte, France) is routinely used in hepatoma therapy. The temperature-sensitive hydrogel polyethylene glycol-b-poly-DL-lactic acid-co-glycolic acid-b-polyethylene glycol triblock copolymer is used as an embolic agent and sustained drug release system. This study attempted to combine the polyethylene glycol-b-poly-DL-lactic acid-co-glycolic acid-b-polyethylene glycol hydrogel and radio-labeled Lipiodol to form a new radio-thermogelling emulsion, rhenium-188-N,N'-1,2-ethanediylbis-L-cysteine diethyl-ester dihydrochloride-Lipiodol/hydrogel ((188)Re-ELH). The therapeutic potential of (188)Re-ELH was evaluated in a rodent hepatoma model. Rhenium-188 chelated with N,N'-1,2-ethanediylbis-L-cysteine diethyl-ester dihydrochloride was extracted with Lipiodol to obtain rhenium-188-N,N'-1,2-ethanediylbis-L-cysteine diethyl-ester dihydrochloride-Lipiodol ((188)Re-EL), which was blended with the hydrogel in equal volumes to develop (188)Re-ELH. The (188)Re-ELH phase stability was evaluated at different temperatures. Biodistribution patterns and micro-single-photon emission computed tomography/computed tomography images in Sprague Dawley rats implanted with the rat hepatoma cell line N1-S1 were observed after in situ tumoral injection of ~3.7 MBq (188)Re-ELH. The therapeutic potential of (188)Re-EL (48.58±3.86 MBq/0.1 mL, n=12) was evaluated in a 2-month survival study using the same animal model. The therapeutic effects of (188)Re-ELH (25.52±4.64 MBq/0.1 mL, n=12) were evaluated and compared with those of (188)Re-EL. The responses were assessed by changes in tumor size and survival rates. The (188)Re-ELH emulsion was stable in the gel form at 25°C-35°C for >52 hours. Biodistribution data and micro-single-photon emission computed tomography/computed tomography images of the (188)Re-ELH group indicated that most activity was selectively observed in hepatomas. Long-term (188)Re-ELH studies have demonstrated protracted reductions in tumor volumes and positive effects on the survival rates (75%) of N1-S1 hepatoma-bearing rats. Conversely, the 2-month survival rate was 13% in the control sham group. Therapeutic responses differed significantly between the two groups (P<0.005). Thus, the hydrogel enhanced the injection stability of (188)Re-EL in an animal hepatoma model. Given the synergistic results, direct (188)Re-ELH intratumoral injection is a potential therapeutic alternative for hepatoma treatment.

  16. Preparation and therapeutic evaluation of 188Re-thermogelling emulsion in rat model of hepatocellular carcinoma

    PubMed Central

    Shih, Ying-Hsia; Lin, Xi-Zhang; Yeh, Chung-Hsin; Peng, Cheng-Liang; Shieh, Ming-Jium; Lin, Wuu-Jyh; Luo, Tsai-Yueh

    2014-01-01

    Radiolabeled Lipiodol® (Guerbet, Villepinte, France) is routinely used in hepatoma therapy. The temperature-sensitive hydrogel polyethylene glycol-b-poly-DL-lactic acid-co-glycolic acid-b-polyethylene glycol triblock copolymer is used as an embolic agent and sustained drug release system. This study attempted to combine the polyethylene glycol-b-poly-DL-lactic acid-co-glycolic acid-b-polyethylene glycol hydrogel and radio-labeled Lipiodol to form a new radio-thermogelling emulsion, rhenium-188–N,N’-1,2-ethanediylbis-L-cysteine diethyl-ester dihydrochloride–Lipiodol/hydrogel (188Re-ELH). The therapeutic potential of 188Re-ELH was evaluated in a rodent hepatoma model. Rhenium-188 chelated with N,N’-1,2-ethanediylbis-L-cysteine diethyl-ester dihydrochloride was extracted with Lipiodol to obtain rhenium-188–N,N’-1,2-ethanediylbis-L-cysteine diethyl-ester dihydrochloride–Lipiodol (188Re-EL), which was blended with the hydrogel in equal volumes to develop 188Re-ELH. The 188Re-ELH phase stability was evaluated at different temperatures. Biodistribution patterns and micro-single-photon emission computed tomography/computed tomography images in Sprague Dawley rats implanted with the rat hepatoma cell line N1-S1 were observed after in situ tumoral injection of ~3.7 MBq 188Re-ELH. The therapeutic potential of 188Re-EL (48.58±3.86 MBq/0.1 mL, n=12) was evaluated in a 2-month survival study using the same animal model. The therapeutic effects of 188Re-ELH (25.52±4.64 MBq/0.1 mL, n=12) were evaluated and compared with those of 188Re-EL. The responses were assessed by changes in tumor size and survival rates. The 188Re-ELH emulsion was stable in the gel form at 25°C–35°C for >52 hours. Biodistribution data and micro-single-photon emission computed tomography/computed tomography images of the 188Re-ELH group indicated that most activity was selectively observed in hepatomas. Long-term 188Re-ELH studies have demonstrated protracted reductions in tumor volumes and positive effects on the survival rates (75%) of N1-S1 hepatoma-bearing rats. Conversely, the 2-month survival rate was 13% in the control sham group. Therapeutic responses differed significantly between the two groups (P<0.005). Thus, the hydrogel enhanced the injection stability of 188Re-EL in an animal hepatoma model. Given the synergistic results, direct 188Re-ELH intratumoral injection is a potential therapeutic alternative for hepatoma treatment. PMID:25214783

  17. Multicolor Electrochromic Displays Exploratory Development

    DTIC Science & Technology

    1989-07-01

    Electrodes with PEG Plasticizers in KCI ...................... 42 6. Electrodes in KCI-AMPS and KCI-PolyAMPS Electrolytes .. 43 7. Orange/Blue Cycling...ethylene glycol) ( PEG ) preparations with average molecular weights of 300 and 3350 were from J.T. Baker Chemical Co. 3. Conductive Substrates Most of...crystallization of the dye. Poly(ethylene glycols) of molecular weights 300 and 3350 were introduced by incorporating them in the IM KCI electrolyte

  18. Utilization of Triton X-100 and polyethylene glycols during surfactant-mediated biodegradation of diesel fuel.

    PubMed

    Wyrwas, Bogdan; Chrzanowski, Łukasz; Ławniczak, Łukasz; Szulc, Alicja; Cyplik, Paweł; Białas, Wojciech; Szymański, Andrzej; Hołderna-Odachowska, Aleksandra

    2011-12-15

    The hypothesis regarding preferential biodegradation of surfactants applied for enhancement of microbial hydrocarbons degradation was studied. At first the microbial degradation of sole Triton X-100 by soil isolated hydrocarbon degrading bacterial consortium was confirmed under both full and limited aeration with nitrate as an electron acceptor. Triton X-100 (600 mg/l) was utilized twice as fast for aerobic conditions (t(1/2)=10.3h), compared to anaerobic conditions (t(1/2)=21.8h). HPLC/ESI-MS analysis revealed the preferential biodegradation trends in both components classes of commercial Triton X-100 (alkylphenol ethoxylates) as well as polyethylene glycols. The obtained results suggest that the observed changes in the degree of ethoxylation for polyethylene glycol homologues occurred as a consequence of the 'central fission' mechanism during Triton X-100 biodegradation. Subsequent experiments with Triton X-100 at approx. CMC concentration (150 mg/l) and diesel oil supported our initial hypothesis that the surfactant would become the preferred carbon source even for hydrocarbon degrading bacteria. Regardless of aeration regimes Triton X-100 was utilized within 48-72 h. Efficiency of diesel oil degradation was decreased in the presence of surfactant for aerobic conditions by approx. 25% reaching 60 instead of 80% noted for experiments without surfactant. No surfactant influence was observed for anaerobic conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Combined Magnesium/Polyethylene Glycol Facilitates the Neuroprotective Effects of Magnesium in Traumatic Brain Injury at a Reduced Magnesium Dose.

    PubMed

    Busingye, Diana S; Turner, Renée J; Vink, Robert

    2016-10-01

    While a number of studies have shown that free magnesium (Mg) decline is a feature of traumatic brain injury (TBI), poor central penetration of Mg has potentially limited clinical translation. This study examines whether polyethylene glycol (PEG) facilitates central penetration of Mg after TBI, increasing neuroprotection while simultaneously reducing the dose requirements for Mg. Rats were exposed to diffuse TBI and administered intravenous MgCl2 either alone (254 μmol/kg or 25.4 μmol/kg) or in combination with PEG (1 g/kg PEG) at 30-min postinjury. Vehicle-treated (saline or PEG) and sham animals served as controls. All animals were subsequently assessed for blood-brain barrier permeability and edema at 5 h, and functional outcome for 1 week postinjury. Optimal dose (254 μmol/kg) MgCl2 or Mg PEG significantly improved all outcome parameters compared to vehicle or PEG controls. Intravenous administration of 10% MgCl2 alone (25.4 μmol/kg) had no beneficial effect on any of the outcome parameters, whereas 10% Mg in PEG had the same beneficial effects as optimal dose Mg administration. Polyethylene glycol facilitates central penetration of Mg following TBI, reducing the concentration of Mg required to confer neuroprotection while simultaneously reducing the risks associated with high peripheral Mg concentration. © 2016 John Wiley & Sons Ltd.

  20. Feasibility of a novel low-volume and sodium phosphate-free bowel preparation regimen for colon capsule endoscopy.

    PubMed

    Zhou, Jieqiong; Tang, Xiaowei; Wang, Jing; Chen, Zhenyu; Wang, Xinying; Jiang, Bo

    2017-08-01

    Bowel preparation regimens for colon capsule endoscopy are not yet standardized since they are not well optimized. The aim of the present study was to evaluate the feasibility of a novel low-volume and sodium phosphate-free bowel preparation regimen for colon capsule endoscopy. A total of 31 patients were prospectively enrolled. In the novel regimen, on the day prior to examination, a low-fiber diet was permitted, 5 mg mosapride citrate was administered twice (1 h prior to lunch and supper) and 1 l polyethylene glycol was administered in the evening. On the day of the examination, an additional 1 l polyethylene glycol, 5 mg mosapride citrate and 200 mg simethicone were administered before capsule ingestion. Polyethylene glycol booster (0.5 l) was administered twice, at 1 and 4 h following capsule ingestion. Colon cleansing levels, ileocecal valve transit time and completion rate were evaluated. A total of 29 patients were included in the final analysis, 90% of whom achieved adequate preparation of the overall colon. Ileocecal valve transit time was 2.35±0.82 h and completion rate was 79.3%. The results revealed that the novel low-volume and sodium phosphate-free bowel preparation regimen for colon capsule endoscopy was feasible, with adequate colon cleansing and completion rates, and has the potential to be used as an alternative regimen.

  1. Use of 5'-γ-ferrocenyl adenosine triphosphate (Fc-ATP) bioconjugates having poly(ethylene glycol) spacers in kinase-catalyzed phosphorylations.

    PubMed

    Martić, Sanela; Rains, Meghan K; Freeman, Daniel; Kraatz, Heinz-Bernhard

    2011-08-17

    The 5'-γ-ferrocenyl adenosine triphosphate (Fc-ATP) bioconjugates (3 and 4), containing the poly(ethylene glycol) spacers, were synthesized and compared to a hydrophobic analogue as co-substrates for the following protein kinases: sarcoma related kinase (Src), cyclin-dependent kinase (CDK), casein kinase II (CK2α), and protein kinase A (PKA). Electrochemical kinase assays indicate that the hydrophobic Fc-ATP analogue was an optimal co-substrate for which K(M) values were determined to be in the 30-200 μM range, depending on the particular protein kinase. The luminescence kinase assay demonstrated the kinase utility for all Fc-ATP conjugates, which is in line with the electrochemical data. Moreover, Fc-ATP bioconjugates exhibit competitive behavior with respect to ATP. Relatively poor performance of the polar Fc-ATP bioconjugates as co-substrates for protein kinases was presumably due to the additional H-bonding and electrostatic interactions of the poly(ethylene glycol) linkers of Fc-ATP with the kinase catalytic site and the target peptides. Phosphorylation of the full-length protein, His-tagged pro-caspase-3, was demonstrated through Fc-phosphoamide transfer to the Ser residues of the surface-bound protein by electrochemical means. These results suggest that electrochemical detection of the peptide and protein Fc-phosphorylation via tailored Fc-ATP co-substrates may be useful for probing protein-protein interactions.

  2. Production of mono- and di-carboxylated polyethylene glycols as a factor obstacle to the successful ozonation-assisted biodegradation of ethoxylated compounds.

    PubMed

    Nakai, Satoshi; Okuda, Tetsuji; Nishijima, Wataru; Okada, Mitsumasa

    2015-10-01

    Ozonation is believed to improve the biodegradability of organic compounds. In the present study, degradation of nonylphenol ethoxylates (NPEOs) was monitored in hybrid treatment systems consisting of ozonation and microbial degradation processes. We found that ozonation of NPEOs decreased, rather than increased, the biodegradability under certain conditions. The timing of ozonation was a definitive factor in determining whether ozonation increased or decreased the biodegradation rates of NPEOs. Initial ozonation of NPEOs prior to biodegradation reduced the rate of dissolved organic carbon (DOC) removal during the subsequent 14 d of biodegradation, whereas intermediate ozonation at the 9th day of biodegradation improved subsequent DOC removal during 14 d of NPEO biodegradation. Furthermore, reduction of DOC removal was also observed, when initial ozonation prior to biodegradation was subjected to cetyl alcohol ethoxylates. The production of less biodegradable intermediates, such as mono- and dicarboxylated polyethylene glycols (MCPEGs and DCPEGs), was responsible for the negative effect of ozonation on biodegradability of NPEOs. DCPEGs and MCPEGs were produced by biodegradation of polyethylene glycols (PEGs) that were ozonolysis products of the NPEOs, and the biodegradability of DCPEGs and MCPEGs was less than that of the precursor PEGs. The results indicate that, if the target chemicals contain ethoxy chains, production of PEGs may be one of the important factors when ozonation is considered. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Acoustic, Thermal and Molecular Interactions of Polyethylene Glycol (2000, 3000, 6000)

    NASA Astrophysics Data System (ADS)

    Venkatramanan, K.; Padmanaban, R.; Arumugam, V.

    Polyethylene Glycol (PEG) is a condensation polymer of ethylene oxide and water. PEG find its application as emulsifying agents, detergents, soaps, plasticizers, ointments, etc. Though the chemical and physical properties of PEG are known, still because of their uses in day to day life, it becomes necessary to study few physical properties like ultrasonic velocity, viscosity and hence adiabatic compressibility, free length, etc. In the present study, an attempt has been made to compute the activation energy and hence to analyse the molecular interactions of aqueous solutions of Polyethylene Glycol of molar mass 2000, 3000 and 6000 at different concentrations (2%, 4%, 6%, 8% and 10%) at different temperatures (303K, 308K, 313K, 318K) by determining relative viscosity, ultrasonic velocity and density. Various parameters like adiabatic compressibility, viscous relaxation time, inter molecular free length, free volume, internal pressure, etc are calculated at 303K and the results are discussed in the light of polymer-solvent interaction. This study helps to understand the behavior of macro-molecules with respect to changing concentration and temperature. Furthermore, viscosity and activation energy results are correlated to understand the increased entanglement of the polymer chains due to the increase in the concentration of a polymer solution that leads to an increase in viscosity and an increase in the activation energy of viscous flow.

  4. The "New Polyethylene Glycol Dilemma": Polyethylene Glycol Impurities and Their Paradox Role in mAb Crystallization.

    PubMed

    Hildebrandt, Christian; Joos, Lea; Saedler, Rainer; Winter, Gerhard

    2015-06-01

    Polyethylene glycols (PEG) represent the most successful and frequently applied class of excipients used for protein crystallization. PEG auto-oxidation and formation of impurities such as peroxides and formaldehydes that foster protein drug degradation is known. However, their effect on mAb crystallization has not been studied in detail before. During the present study, a model IgG1 antibody (mAb1) was crystallized in PEG solutions. Aggregate formation was observed during crystallization and storage that was ascribed to PEG degradation products. Reduction of peroxide and formaldehyde levels prior to crystallization by vacuum and freeze-drying was investigated for its effect on protein degradation. Vacuum drying was superior in removal of peroxides but inferior in reducing formaldehyde residues. Consequently, double purification allowed extensive removal of both impurities. Applying of purified PEG led to 50% lower aggregate fractions. Surprisingly, PEG double purification or addition of methionine prior to crystallization prevented crystal formation. With increased PEG concentration or spiking with peroxides and formaldehydes, crystal formation could be recovered again. With these results, we demonstrate that minimum amounts of oxidizing impurities and thus in consequence chemically altered proteins are vital to initiate mAb1 crystallization. The present study calls PEG as good precipitant for therapeutic biopharmaceuticals into question. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  5. A novel self-assembled nanoparticle platform based on pectin-eight-arm polyethylene glycol-drug conjugates for co-delivery of anticancer drugs.

    PubMed

    Liu, Yanxue; Liu, Kefeng; Li, Xiaomin; Xiao, Shangzhen; Zheng, Dan; Zhu, Pengbo; Li, Chunxiao; Liu, Jing; He, Jing; Lei, Jiandu; Wang, Luying

    2018-05-01

    The application of non-toxic carriers to increase drug loading, multi-drug delivery, and extremely small size of nano-drugs to construct a tremendous transmission system is the goal for all researchers to be pursued. The proposal of natural pectin nano-platform for delivery of multiple drugs is critical for biomedical research, especially a particle size of below 100nm with high yield. Here we design a new core-shell structure pectin-eight-arm polyethylene glycol-ursolic acid/hydrooxycampothecin nanoparticle (Pec-8PUH NPs) through a special self-assembly method for stabilizing and dispersing particles, improving water-solubility, and achieving drug controlled release. The obtained Pec-8PUH NPs possessed appropriate size (~91nm), drug-loaded efficiency and encapsulation efficiency through the regulation of eight-arm polyethylene glycol. In addition, Pec-8PUH NPs could enhance cell cytotoxicity, shorten blood retention time (7.3-fold UA, 7.2-fold HCPT) and more effective cellular uptake than free drugs, which exhibited an obvious synergistic effect of UA and HCPT by the co-delivery. 4T1 tumor-bearing mice also showed a higher survival rate than free UA and free HCPT. The result further shows that this novel drug delivery system has a promising potential for anti-cancer combination therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Microporous Poly(L-Lactic Acid) Membranes Fabricated by Polyethylene Glycol Solvent-Cast/Particulate Leaching Technique

    PubMed Central

    Selvam, Shivaram; Chang, Wenji V.; Nakamura, Tamako; Samant, Deedar M.; Thomas, Padmaja B.; Trousdale, Melvin D.; Mircheff, Austin K.; Schechter, Joel E.

    2009-01-01

    With the eventual goal of developing a tissue-engineered tear secretory system, we found that primary lacrimal gland acinar cells grown on solid poly(L-lactic acid) (PLLA) supports expressed the best histiotypic morphology. However, to be able to perform vectorial transport functions, epithelia must be supported by a permeable substratum. In the present study, we describe the use of a solvent-cast/particulate leaching technique to fabricate microporous PLLA membranes (mpPLLAm) from PLLA/polyethylene glycol blends. Scanning electron microscopy revealed pores on both the air-cured (∼4 μm) and glass-cured sides (<2 μm) of the mpPLLAm. Diffusion studies were performed with mpPLLAm fabricated from 57.1% PLLA/42.9% polyethylene glycol blends to confirm the presence of channelized pores. The data reveal that glucose, L-tryptophan, and dextran (a high molecular weight glucose polymer) readily permeate mpPLLAm. Diffusion of the immunoglobulin G through the mpPLLAm decreased with time, suggesting the possible adsorption and occlusion of the pores. Cells cultured on the mpPLLAm (57.1/42.9 wt%) grew to subconfluent monolayers but retained histiotypic morphological and physiological characteristics of lacrimal acinar cells in vivo. Our results suggest that mpPLLAm fabricated using this technique may be useful as a scaffold for a bioartificial lacrimal gland device. PMID:19260769

  7. Polyethylene glycol inhibits intestinal neoplasia and induces epithelial apoptosis in Apc(min) mice.

    PubMed

    Roy, Hemant K; Gulizia, James; DiBaise, John K; Karolski, William J; Ansari, Sajid; Madugula, Madhavi; Hart, John; Bissonnette, Marc; Wali, Ramesh K

    2004-11-08

    Efficacy of a safe and clinically utilized polyethylene glycol formulation (PEG-3350) to suppress intestinal tumors was investigated in the Apc(min) mouse-model of experimental carcinogenesis. Furthermore, based on our previous finding on the induction of apoptosis in HT-29 cells by PEG, we evaluated its ability to stimulate epithelial cell apoptosis in both Apc(min) mouse as well as AOM-treated rat as a potential molecular mechanism of chemoprevention. Twenty-two Apc(min) mice were randomized equally to PEG or vehicle (control) supplementation. Tumors were scored and uninvolved intestinal mucosal apoptosis was assayed using a modified terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) assay and by immunohistochemical detection of cleaved caspase-3. Supplementation of Apc(min) mice with 10% PEG 3350 (in drinking water) resulted in a 48% (P<0.05) reduction in intestinal tumor burden and induced 2-3 fold increase in mucosal apoptosis. Dietary supplementation of polyethylene glycol (5%) also stimulated colonic mucosal apoptosis 4-5 fold in AOM-treated rats, the regimen that we previously reported to reduce tumor burden by 76% (P<0.05). In summary, we demonstrate, for the first time, that PEG does protect against Apc(min) mouse tumorigenesis. The correlation between pro-apoptotic actions and chemopreventive efficacy of PEG in these models strongly implicates induction of apoptosis as one of the impending mechanisms of chemoprevention.

  8. Laser textured Co-Cr-Mo alloy stored chitosan/poly(ethylene glycol) composite applied on artificial joints lubrication.

    PubMed

    Lu, Hailin; Ren, Shanshan; Guo, Junde; Li, Yue; Li, Jianhui; Dong, Guangneng

    2017-09-01

    Arthroplasty brings the wear problems because of body fluid has poor performance as lubricant. Lubricant which is used in artificial joints will rapidly degrade and be absorbed by human body after injecting. To prolong the lubricant's effectiveness, this study prepared chitosan/poly(ethylene glycol) (CS/PEG) and textures to play a role in joint lubrication and wear protection. Chitosan (CS) and poly(ethylene glycol) which have biocompatibility and biodegradability properties can be used in human body. The tribological results shown that CS/PEG sol has excellent performance when this sol was composed by 2wt% CS and 30wt% PEG, the average friction coefficient below 0.016 under the condition of 30-90N load (pressure 4.2-12.6MPa). In this study, CS/PEG was added in the texture of artificial joints, then the surfaces of the CS/PEG formed gel via NaOH solidification effect. The CS/PEG gel film could prevent the CS/PEG sol from diluting in body fluid. Meanwhile, FT-IR, XRD, UV/vis and Raman spectra revealed that CS associated with PEG via hydrogen bond effect may form a particular structure, which leaded the good tribological performance. This study provides a new, simple and green approach to enhance tribological performances of artificial joints. Copyright © 2017. Published by Elsevier B.V.

  9. Formulation of polylactide-co-glycolic acid nanospheres for encapsulation and sustained release of poly(ethylene imine)-poly(ethylene glycol) copolymers complexed to oligonucleotides

    PubMed Central

    Sirsi, Shashank R; Schray, Rebecca C; Wheatley, Margaret A; Lutz, Gordon J

    2009-01-01

    Antisense oligonucleotides (AOs) have been shown to induce dystrophin expression in muscles cells of patients with Duchenne Muscular Dystrophy (DMD) and in the mdx mouse, the murine model of DMD. However, ineffective delivery of AOs limits their therapeutic potential. Copolymers of cationic poly(ethylene imine) (PEI) and non-ionic poly(ethylene glycol) (PEG) form stable nanoparticles when complexed with AOs, but the positive surface charge on the resultant PEG-PEI-AO nanoparticles limits their biodistribution. We adapted a modified double emulsion procedure for encapsulating PEG-PEI-AO polyplexes into degradable polylactide-co-glycolic acid (PLGA) nanospheres. Formulation parameters were varied including PLGA molecular weight, ester end-capping, and sonication energy/volume. Our results showed successful encapsulation of PEG-PEI-AO within PLGA nanospheres with average diameters ranging from 215 to 240 nm. Encapsulation efficiency ranged from 60 to 100%, and zeta potential measurements confirmed shielding of the PEG-PEI-AO cationic charge. Kinetic measurements of 17 kDa PLGA showed a rapid burst release of about 20% of the PEG-PEI-AO, followed by sustained release of up to 65% over three weeks. To evaluate functionality, PEG-PEI-AO polyplexes were loaded into PLGA nanospheres using an AO that is known to induce dystrophin expression in dystrophic mdx mice. Intramuscular injections of this compound into mdx mice resulted in over 300 dystrophin-positive muscle fibers distributed throughout the muscle cross-sections, approximately 3.4 times greater than for injections of AO alone. We conclude that PLGA nanospheres are effective compounds for the sustained release of PEG-PEI-AO polyplexes in skeletal muscle and concomitant expression of dystrophin, and may have translational potential in treating DMD. PMID:19351396

  10. Polyethylene glycol-based ultrasound-assisted extraction of magnolol and honokiol from Cortex Magnoliae Officinalis.

    PubMed

    He, Lei; Fan, Tao; Hu, Jianguo; Zhang, Lijin

    2015-01-01

    In this study, a kind of green solvent named polyethylene glycol (PEG) was developed for the ultrasound-assisted extraction (UAE) of magnolol and honokiol from Cortex Magnoliae Officinalis. The effects of PEG molecular weight, PEG concentration, sample size, pH, ultrasonic power and extraction time on the extraction of magnolol and honokiol were investigated to optimise the extraction conditions. Under the optimal extraction conditions, the PEG-based UAE supplied higher extraction efficiencies of magnolol and honokiol than the ethanol-based UAE and traditional ethanol-reflux extraction. Furthermore, the correlation coefficient (R(2)), repeatability (relative standard deviation, n = 6) and recovery confirmed the validation of the proposed extraction method, which were 0.9993-0.9996, 3.1-4.6% and 92.3-106.8%, respectively.

  11. Breakdown of the Stokes-Einstein Relation for the Rotational Diffusivity of Polymer Grafted Nanoparticles in Polymer Melts.

    PubMed

    Maldonado-Camargo, Lorena; Rinaldi, Carlos

    2016-11-09

    We report observations of breakdown of the Stokes-Einstein relation for the rotational diffusivity of polymer-grafted spherical nanoparticles in polymer melts. The rotational diffusivity of magnetic nanoparticles coated with poly(ethylene glycol) dispersed in poly(ethylene glycol) melts was determined through dynamic magnetic susceptibility measurements of the collective rotation of the magnetic nanoparticles due to imposed time-varying magnetic torques. These measurements clearly demonstrate the existence of a critical molecular weight for the melt polymer, below which the Stokes-Einstein relation accurately describes the rotational diffusivity of the polymer-grafted nanoparticles and above which the Stokes-Einstein relation ceases to apply. This critical molecular weight was found to correspond to a chain contour length that approximates the hydrodynamic diameter of the nanoparticles.

  12. Assessment of a method for measuring serum thyroxine by radioimmunoassay, with use of polyethylene glycol precipitation. [/sup 125/I tracer technique

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Farid, N.R.; Kennedy, C.

    We assessed the efficacy of a new thyroxine radioimmunoassay kit (Abbott) in which polyethylene glycol is used to separate bound from free hormone. Mean serum thyroxine was 88 +- 15 (+-SD) ..mu..g/liter for 96 normal persons. Results for hypothyroid and hyperthyroid persons were clearly separated from those for normal individuals. Women taking oral contraceptive preparations showed variable increases in their serum thyroxine values. The coefficient of variation ranged from 1 to 3% within assay and from 5.4 to 11% among different assays. Excellent parallelism was demonstrated between thyroxine values estimated by this method and those obtained either by competitive proteinmore » binding or by a separate radioimmunoassay for the hormone.« less

  13. Diagnostic of protein crystallization by dynamic light scattering; an application to an aminoacyl-tRNA synthetase

    NASA Astrophysics Data System (ADS)

    Mikol, Vincent; Vincendon, Pascale; Eriani, Gilbert; Hirsch, Ernest; Giegé, Richard

    1991-03-01

    The apparent hydrodynamic radius of a truncated form of baker's yeast aspartyl-tRNA synthetase has been measured in various precipitating agent solutions as a function of the protein concentration by dynamic light scattering. In solvents containing ammonium sulfate or 2-methyl-2,4-pentanediol as the precipitating agent the protein remains essentially monodisperse, whereas in the presence of polyethylene glycol interactions and aggregations between protein molecules are detected before reaching supersaturation. These data are indications of possible crystallizations of the protein by the two former precipitants and no crystallization by the latter one. Crystallization experiments indeed have shown that the truncated synthetase crystallizes in the presence of ammonium sulfate and that no crystals grow in solvents containing polyethylene glycol.

  14. The Osmotic Potential of Polyethylene Glycol 6000 1

    PubMed Central

    Michel, Burlyn E.; Kaufmann, Merrill R.

    1973-01-01

    Osmotic potential (ψs) of aqueous solutions of polyethylene glycol 6000 (PEG-6000) was curvilinearly related to concentration. At given concentrations, ψs increased linearly with temperature. The effects of concentration and temperature on ψs of PEG-6000 solutions differ from those for most salts and sugars and apparently are related to structural changes in the PEG polymer. Measurements of ψs with thermocouple psychrometers are more negative than those with a vapor pressure osmometer, with the psychrometer probably giving the more nearly correct ψs for bulk solutions. An empirical equation permits calculation of ψs from known concentrations of PEG-6000 over a temperature range of 15 to 35 C. Viscometery and gravimetric analysis are convenient methods by which the concentrations of PEG-6000 solutions may be measured. PMID:16658439

  15. The osmotic potential of polyethylene glycol 6000.

    PubMed

    Michel, B E; Kaufmann, M R

    1973-05-01

    Osmotic potential (psi(s)) of aqueous solutions of polyethylene glycol 6000 (PEG-6000) was curvilinearly related to concentration. At given concentrations, psi(s) increased linearly with temperature. The effects of concentration and temperature on psi(s) of PEG-6000 solutions differ from those for most salts and sugars and apparently are related to structural changes in the PEG polymer. Measurements of psi(s) with thermocouple psychrometers are more negative than those with a vapor pressure osmometer, with the psychrometer probably giving the more nearly correct psi(s) for bulk solutions. An empirical equation permits calculation of psi(s) from known concentrations of PEG-6000 over a temperature range of 15 to 35 C. Viscometery and gravimetric analysis are convenient methods by which the concentrations of PEG-6000 solutions may be measured.

  16. Catechol-grafted poly(ethylene glycol) for PEGylation on versatile substrates.

    PubMed

    Lee, Hyukjin; Lee, Kang Dae; Pyo, Kyung Bo; Park, Sung Young; Lee, Haeshin

    2010-03-16

    We report on catechol-grafted poly(ethylene) glycol (PEG-g-catechol) for the preparation of nonfouling surfaces on versatile substrates including adhesion-resistant PTFE. PEG-g-catechol was prepared by the step-growth polymerization of PEO to which dopamine, a mussel-derived adhesive molecule, was conjugated. The immersion of substrates into an aqueous solution of PEG-g-catechol resulted in robust PEGylation on versatile surfaces of noble metals, oxides, and synthetic polymers. Surface PEGylation was unambiguously confirmed by various surface analytical tools such as ellipsometry, goniometry, infrared spectroscopy, and X-ray photoelectron spectroscopy. Contrary to existing PEG derivatives that are difficult-to-modify synthetic polymer surfaces, PEG-g-catechol can be considered to be a new class of PEGs for the facile surface PEGylation of various types of surfaces.

  17. Crystallization and preliminary X-ray analysis of gamma-glutamyltranspeptidase from Escherichia coli K-12.

    PubMed

    Kumagai, H; Nohara, S; Suzuki, H; Hashimoto, W; Yamamoto, K; Sakai, H; Sakabe, K; Fukuyama, K; Sakabe, N

    1993-12-20

    gamma-Glutamyltranspeptidase (EC 2.3.2.2) from Escherichia coli K-12 has been purified and crystallized by means of vapor diffusion in hanging drops. Two kinds of crystals on cell dimensions were found for X-ray diffraction analysis, one from ammonium sulfate and the other from polyethylene glycol 6000 as precipitants. The crystals of the orthorhombic form grown in the presence of 15% polyethylene glycol and 20 mM sodium acetate buffer were chosen for further analysis. The crystals belonged to space group P2(1)2(1)2(1), with cell dimensions of a = 128.1, b = 129.9 and c = 79.2 A, and two molecules constitute an asymmetric unit. These crystals diffracted to 2.0 A resolution and were suitable for X-ray crystallographic studies.

  18. Polyethylene-Glycol-Mediated Self-Assembly of Magnetite Nanoparticles at the Liquid/Vapor Interface

    DOE PAGES

    Vaknin, David; Wang, Wenjie; Islam, Farhan; ...

    2018-03-23

    It is shown that magnetite nanoparticles (MagNPs) grafted with polyethylene glycol (PEG) self-assemble and short-range-order as 2D films at surfaces of aqueous suspensions by manipulating salt concentrations. Synchrotron X-ray reflectivity and grazing-incidence small angle X-ray scattering studies reveal that K 2CO 3 induces the migration of the PEG-MagNPs to the liquid/vapor interface to form a Gibbs layer of monoparticle in thickness. As the salt concentration and/or nanoparticle concentration increase, the surface-adsorbed nanoparticles become more organized. And further increase in salt concentration leads to the growth of an additional incomplete nanoparticle layer contiguous to the first one at the vapor/liquid interfacemore » that remains intact.« less

  19. Simulation of polyethylene glycol and calcium-mediated membrane fusion

    NASA Astrophysics Data System (ADS)

    Pannuzzo, Martina; De Jong, Djurre H.; Raudino, Antonio; Marrink, Siewert J.

    2014-03-01

    We report on the mechanism of membrane fusion mediated by polyethylene glycol (PEG) and Ca2+ by means of a coarse-grained molecular dynamics simulation approach. Our data provide a detailed view on the role of cations and polymer in modulating the interaction between negatively charged apposed membranes. The PEG chains cause a reduction of the inter-lamellar distance and cause an increase in concentration of divalent cations. When thermally driven fluctuations bring the membranes at close contact, a switch from cis to trans Ca2+-lipid complexes stabilizes a focal contact acting as a nucleation site for further expansion of the adhesion region. Flipping of lipid tails induces subsequent stalk formation. Together, our results provide a molecular explanation for the synergistic effect of Ca2+ and PEG on membrane fusion.

  20. Water and UV degradable lactic acid polymers

    DOEpatents

    Bonsignore, P.V.; Coleman, R.D.

    1996-10-08

    A water and UV light degradable copolymer is described made from monomers of lactic acid and a modifying monomer selected from the class consisting of ethylene glycol, propylene glycol, P-dioxanone, 1,5 dioxepan-2-one, 1,4-oxathialan-2-one, 1,4-dioxide and mixtures thereof. These copolymers are useful for waste disposal and agricultural purposes. Also disclosed is a water degradable blend of polylactic acid or modified polylactic acid and high molecular weight polyethylene oxide wherein the high molecular weight polyethylene oxide is present in the range of from about 2 by weight to about 50% by weight, suitable for films. A method of applying an active material selected from the class of seeds, seedlings, pesticides, herbicides, fertilizers and mixtures thereof to an agricultural site is also disclosed.

  1. Size fractionation of double-stranded DNA by precipitation with polyethylene glycol

    PubMed Central

    Lis, John T.; Schleif, Robert

    1975-01-01

    We show that DNA molecules of differing molecular mass are separable by selective precipitation with polyethylene glycol (PEG†). Higher molecular mass DNA precipitates at lower PEG concentrations than lower molecular mass DNA. Double-stranded DNA can be fractionated at least in the range of 3 × 107 to 1 × 105 daltons. The effects of PEG concentration, sodium chloride concentration, DNA concentration, pH, divalent ions, precipitation time, and centrifugal force have been determined. These studies show PEG precipitation offers a size fractionation method for DNA which is convenient, of high capacity, and applicable over a wide range of conditions. However, resolution is not high and separation of two species approaches 100% only if they differ in molecular mass by at least a factor of two. Images PMID:236548

  2. Amino acids and peptides. XXXII: A bifunctional poly(ethylene glycol) hybrid of fibronectin-related peptides.

    PubMed

    Maeda, M; Izuno, Y; Kawasaki, K; Kaneda, Y; Mu, Y; Tsutsumi, Y; Lem, K W; Mayumi, T

    1997-12-18

    An amino acid type poly(ethylene glycol) (aaPPEG) was prepared and its application to a drug carrier was examined. The peptides, Arg-Gly-Asp (RGD) and Glu-Ile-Leu-Asp-Val (EILDV) which were reported as active fragments of Fibronectin (a cell adhesion protein), were conjugated with aaPEG (molecular weight, 10,000). The hybrid, RGD-aaPEG-EILDV, was prepared by a combination of the solid-phase method and the solution method. Antiadhesive activity of the peptides was not lost by its hybrid formation with the large aaPEG molecule. A mixture of RGD (0.43 mmol) and EILDV (0.43 mmol) did not demonstrate an antiadhesive effect, but the hybrid containing 0.43 mmol of each peptide did exhibit this effect.

  3. Hansen solubility parameters for polyethylene glycols by inverse gas chromatography.

    PubMed

    Adamska, Katarzyna; Voelkel, Adam

    2006-11-03

    Inverse gas chromatography (IGC) has been applied to determine solubility parameter and its components for nonionic surfactants--polyethylene glycols (PEG) of different molecular weight. Flory-Huggins interaction parameter (chi) and solubility parameter (delta(2)) were calculated according to DiPaola-Baranyi and Guillet method from experimentally collected retention data for the series of carefully selected test solutes. The Hansen's three-dimensional solubility parameters concept was applied to determine components (delta(d), delta(p), delta(h)) of corrected solubility parameter (delta(T)). The molecular weight and temperature of measurement influence the solubility parameter data, estimated from the slope, intercept and total solubility parameter. The solubility parameters calculated from the intercept are lower than those calculated from the slope. Temperature and structural dependences of the entopic factor (chi(S)) are presented and discussed.

  4. Polyethylene-Glycol-Mediated Self-Assembly of Magnetite Nanoparticles at the Liquid/Vapor Interface

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vaknin, David; Wang, Wenjie; Islam, Farhan

    It is shown that magnetite nanoparticles (MagNPs) grafted with polyethylene glycol (PEG) self-assemble and short-range-order as 2D films at surfaces of aqueous suspensions by manipulating salt concentrations. Synchrotron X-ray reflectivity and grazing-incidence small angle X-ray scattering studies reveal that K 2CO 3 induces the migration of the PEG-MagNPs to the liquid/vapor interface to form a Gibbs layer of monoparticle in thickness. As the salt concentration and/or nanoparticle concentration increase, the surface-adsorbed nanoparticles become more organized. And further increase in salt concentration leads to the growth of an additional incomplete nanoparticle layer contiguous to the first one at the vapor/liquid interfacemore » that remains intact.« less

  5. Cell separation by immunoaffinity partitioning with polyethylene glycol-modified Protein A in aqueous polymer two-phase systems

    NASA Technical Reports Server (NTRS)

    Karr, Laurel J.; Van Alstine, James M.; Snyder, Robert S.; Shafer, Steven G.; Harris, J. Milton

    1988-01-01

    Previous work has shown that polyethylene glycol (PEG)-bound antibodies can be used as affinity ligands in PEG-dextran two-phase systems to provide selective partitioning of cells to the PEG-rich phase. In the present work it is shown that immunoaffinity partitioning can be simplified by use of PEG-modified Protein A which complexes with unmodified antibody and cells and shifts their partitioning into the PEG-rich phase, thus eliminating the need to prepare a PEG-modified antibody for each cell type. In addition, the paper provides a more rigorous test of the original technique with PEG-bound antibodies by showing that it is effective at shifting the partitioning of either cell type of a mixture of two cell populations.

  6. Management of constipation in palliative care patients undergoing opioid therapy: is polyethylene glycol an option?

    PubMed

    Wirz, Stefan; Klaschik, Eberhard

    2005-01-01

    This study assessed the efficacy of laxative use for treatment of constipation in patients receiving opioid therapy, with special attention to polyethylene glycol 3350/electrolyte solution (PEG-ES). Computerized data from 206 patients were analyzed using descriptive statistics. Subgroups were analyzed using confirmatory statistics. Constipation occurred in 42.7 percent of patients. Laxatives were administered to 74.3 percent of these patients using a standardized step scheme, with good results in 78.4 percent. As a therapy for constipation, the combined administration of PEG-ES, sodium picosulphate, and liquid paraffin proved most effective, although statistical analysis yielded no significance. Early use of PEG-ES using a step scheme holds promise for treatment of opioid-related constipation in palliative care patients, although further investigation is warranted.

  7. Ethylene Glycol - Polyethylene Glycol (EG-PEG) Mixtures: Infrared Spectra Wavelet Cross-Correlation Analysis.

    PubMed

    Caccamo, Maria Teresa; Magazù, Salvatore

    2017-03-01

    Infrared spectra were collected on mixtures of ethylene glycol (EG) and polyethylene glycol 600 (PEG600) as a function of weight fraction from pure EG to pure PEG600. In this paper, it will be shown that while the OH vibrational contribution drastically reduces its center frequency from 3450 cm -1 to 3300 cm -1 in the weight fraction range 0-25%, the displacement of the mixture spectral features of the mixtures from ideal behavior, i.e., in the absence of interaction, shows the presence of a non-ideal mixing process. Furthermore, wavelet cross-correlation analysis of the registered pairs of spectra and of the intramolecular O-H stretching contributions reveals how the addition of a small amount of pure EG to PEG600 dramatically influences the structural properties of the polymeric matrix, owing to an increase the intermolecular connectivity. In particular, the wavelet cross-correlation parameters, evaluated between each pair of the registered data as a function of weight fraction, in a linear-logarithmic plot, reveals an inflection point for a weight fraction of about 25% of EG, which confirms that, within the three-dimensional networks of hydrogen-bonded EG-PEG600 molecules, a key role is played by EG in determining an increase in the hydrogen-bond network density.

  8. Vapor pressures of a homologous series of polyethylene glycols as a reference data set for validating vapor pressure measurement techniques.

    NASA Astrophysics Data System (ADS)

    Krieger, Ulrich; Marcolli, Claudia; Siegrist, Franziska

    2015-04-01

    The production of secondary organic aerosol (SOA) by gas-to-particle partitioning is generally represented by an equilibrium partitioning model. A key physical parameter which governs gas-particle partitioning is the pure component vapor pressure, which is difficult to measure for low- and semivolatile compounds. For typical atmospheric compounds like e.g. citric acid or tartaric acid, vapor pressures have been reported in the literature which differ by up to six orders of magnitude [Huisman et al., 2013]. Here, we report vapor pressures of a homologous series of polyethylene glycols (triethylene glycol to octaethylene glycol) determined by measuring the evaporation rate of single, levitated aerosol particles in an electrodynamic balance. We propose to use those as a reference data set for validating different vapor pressure measurement techniques. With each addition of a (O-CH2-CH2)-group the vapor pressure is lowered by about one order of magnitude which makes it easy to detect the lower limit of vapor pressures accessible with a particular technique down to a pressure of 10-8 Pa at room temperature. Reference: Huisman, A. J., Krieger, U. K., Zuend, A., Marcolli, C., and Peter, T., Atmos. Chem. Phys., 13, 6647-6662, 2013.

  9. Polyethylene Glycol 3350

    MedlinePlus

    ... is in a class of medications called osmotic laxatives. It works by causing water to be retained ... 8 ounces (240 milliliters) of water, juice, soda, coffee, or tea. Stir to dissolve the powder. Drink ...

  10. Glycols modulate terminator stem stability and ligand-dependency of a glycine riboswitch.

    PubMed

    Hamachi, Kokoro; Hayashi, Hikari; Shimamura, Miyuki; Yamaji, Yuiha; Kaneko, Ai; Fujisawa, Aruma; Umehara, Takuya; Tamura, Koji

    2013-08-01

    The Bacillus subtilis glycine riboswitch comprises tandem glycine-binding aptamers and a putative terminator stem followed by the gcvT operon. Gene expression is regulated via the sensing of glycine. However, we found that the riboswitch behaves in a "glycine-independent" manner in the presence of polyethylene glycol (PEG) and ethylene glycol. The effect is related to the formation of a terminator stem within the expression platform under such conditions. The results revealed that increasing PEG stabilized the structure of the terminator stem. By contrast, the addition of ethylene glycol destabilized the terminator stem. PEG and ethylene glycol have opposite effects on transcription as well as on stable terminator stem formation. The glycine-independency of the riboswitch and the effects of such glycols might shed light on the evolution of riboswitches. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  11. 40 CFR 721.4040 - Glycols, polyethylene-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium salt. 721.4040 Section 721.4040 Protection of...-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium salt. (a) Chemical..., polyethylene-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetramethyl butyl)phenyl ether, sodium salt (P-90-1565) is...

  12. Molecular dynamics studies of polyethylene oxide and polyethylene glycol: hydrodynamic radius and shape anisotropy.

    PubMed

    Lee, Hwankyu; Venable, Richard M; Mackerell, Alexander D; Pastor, Richard W

    2008-08-01

    A revision (C35r) to the CHARMM ether force field is shown to reproduce experimentally observed conformational populations of dimethoxyethane. Molecular dynamics simulations of 9, 18, 27, and 36-mers of polyethylene oxide (PEO) and 27-mers of polyethylene glycol (PEG) in water based on C35r yield a persistence length lambda = 3.7 A, in quantitative agreement with experimentally obtained values of 3.7 A for PEO and 3.8 A for PEG; agreement with experimental values for hydrodynamic radii of comparably sized PEG is also excellent. The exponent upsilon relating the radius of gyration and molecular weight (R(g) proportional, variantM(w)(upsilon)) of PEO from the simulations equals 0.515 +/- 0.023, consistent with experimental observations that low molecular weight PEG behaves as an ideal chain. The shape anisotropy of hydrated PEO is 2.59:1.44:1.00. The dimension of the middle length for each of the polymers nearly equals the hydrodynamic radius R(h)obtained from diffusion measurements in solution. This explains the correspondence of R(h) and R(p), the pore radius of membrane channels: a polymer such as PEG diffuses with its long axis parallel to the membrane channel, and passes through the channel without substantial distortion.

  13. Strong Stretching of Poly(ethylene glycol) Brushes Mediated by Ionic Liquid Solvation.

    PubMed

    Han, Mengwei; Espinosa-Marzal, Rosa M

    2017-09-07

    We have measured forces between mica surfaces coated with a poly(ethylene glycol) (PEG) brush solvated by a vacuum-dry ionic liquid, 1-ethyl-3-methyl imidazolium bis(trifluoromethylsulfonyl)imide, with a surface forces apparatus. At high grafting density, the solvation mediated by the ionic liquid causes the brush to stretch twice as much as in water. Modeling of the steric repulsion indicates that PEG behaves as a polyelectrolyte; the hydrogen bonding between ethylene glycol and the imidazolium cation seems to effectively charge the polymer brush, which justifies the strong stretching. Importantly, under strong polymer compression, solvation layers are squeezed out at a higher rate than for the neat ionic liquid. We propose that the thermal fluctuations of the PEG chains, larger in the brush than in the mushroom configuration, maintain the fluidity of the ionic liquid under strong compression, in contrast to the solid-like squeezing-out behavior of the neat ionic liquid. This is the first experimental study of the behavior of a polymer brush solvated by an ionic liquid under nanoconfinement.

  14. Polyethylene glycol-conjugated chondroitin sulfate A derivative nanoparticles for tumor-targeted delivery of anticancer drugs.

    PubMed

    Lee, Jae-Young; Park, Ju-Hwan; Lee, Jeong-Jun; Lee, Song Yi; Chung, Suk-Jae; Cho, Hyun-Jong; Kim, Dae-Duk

    2016-10-20

    Polyethylene glycol (PEG)-decorated chondroitin sulfate A-deoxycholic acid (CSD) nanoparticles (NPs) were fabricated for the selective delivery of doxorubicin (DOX) to ovarian cancer. CSD-PEG was synthesized via amide bond formation between the NH2 group of methoxypolyethylene glycol amine and the COOH group of CSD. CSD-PEG/DOX NPs with a 247nm mean diameter, negative zeta potential, and >90% drug encapsulation efficiency were prepared. Sustained and pH-dependent DOX release profiles from CSD-PEG NPs were observed in dissolution tests. Endocytosis of NPs by SKOV-3 cells (CD44 receptor-positive human ovarian cancer cells), based on the CSA-CD44 receptor interaction, was determined by flow cytometry and confocal laser scanning microscopy (CLSM) studies. PEGylation of NPs also resulted in reduced drug clearance (CL) in vivo and improved relative bioavailability, compared to non-PEGylated NPs, as determined by the pharmacokinetic study performed after intravenous administration in rats. Developed CSD-PEG NPs can be a promising delivery vehicle for the therapy of CD44 receptor-expressing ovarian cancers. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Creating low-impedance tetrodes by electroplating with additives

    PubMed Central

    Ferguson, John E.; Boldt, Chris; Redish, A. David

    2011-01-01

    A tetrode is a bundle of four microwires that can record from multiple neurons simultaneously in the brain of a freely moving animal. Tetrodes are usually electroplated to reduce impedances from 2-3 MΩ to 200-500 kΩ (measured at 1 kHz), which increases the signal-to-noise ratio and allows for the recording of small amplitude signals. Tetrodes with even lower impedances could improve neural recordings but cannot be made using standard electroplating methods without shorting. We were able to electroplate tetrodes to 30-70 kΩ by adding polyethylene glycol (PEG) or multi-walled carbon nanotube (MWCNT) solutions to a commercial gold-plating solution. The MWCNTs and PEG acted as inhibitors in the electroplating process and created large-surface-area, low-impedance coatings on the tetrode tips. PMID:21379404

  16. Cast-In-Situ, Large-Sized Monolithic Silica Xerogel Prepared in Aqueous System.

    PubMed

    Ding, Wenhui; Wang, Xiaodong; Chen, Dong; Li, Tiemin; Shen, Jun

    2018-05-15

    This paper reports the preparation of cast-in-situ, large-sized monolithic silica xerogels by a two-step acid⁻base catalyzed approach under ambient pressure drying. Low-cost industrial silica sol and deionized water were used as the silicon source and the solvent, respectively. Hexadecetyltrimethylammonium bromide (CTAB) was used as a modification agent. Different amounts of polyethylene glycol 400 (PEG400) was added as a pore-forming agent. The prepared silica xerogels under ambient pressure drying have a mesoporous structure with a low density of 221 mg·cm -3 and a thermal conductivity of 0.0428 W·m -1 ·K -1 . The low-cost and facile preparation process, as well as the superior performance of the monolithic silica xerogels make it a promising candidate for industrial thermal insulation materials.

  17. Pegylation of Magnetically Oriented Lipid Bilayers

    NASA Astrophysics Data System (ADS)

    King, Valencia; Parker, Margaret; Howard, Kathleen P.

    2000-01-01

    We report NMR data for magnetically oriented phospholipid bilayers which have been doped with a lipid derivatized with a polyethylene glycol polymer headgroup to stabilize samples against aggregation. 13C, 31P, and 2H NMR data indicate that the incorporation of PEG2000-PE (1% molar to DMPC) does not interfere with the orientation properties of bicelles prepared at 25% w/v with or without the presence of lanthanide. Bicelles prepared at 10% w/v are also shown to orient when PEG2000-PE is added. The addition of PEG2000-PE to cholesterol-containing, lanthanide-flipped bicelles is shown to inhibit sample phase separation and improve spectral quality. Furthermore, the addition of PEG2000-PE to high w/v bicelles (40% w/v) is demonstrated to lead to an increase in overall sample order.

  18. A prospective audit of the efficacy, safety, and acceptability of low-volume polyethylene glycol (2 L) versus standard volume polyethylene glycol (4 L) versus magnesium citrate plus stimulant laxative as bowel preparation for colonoscopy.

    PubMed

    Kelly, Nicholas Michael; Rodgers, Colin; Patterson, Neil; Jacob, Sudheer George; Mainie, Inder

    2012-08-01

    High-quality video colonoscopy requires adequate preparation of the bowel to ensure both adequate procedure completion rates and polyp detection rates. We sought to examine our practice to determine which bowel preparation cleansed most effectively in our patients. A prospective audit of the efficacy, safety, and acceptability of low-volume polyethylene glycol (2-L Moviprep; Norgine Pharmaceuticals) versus standard volume polyethylene glycol (4-L KleanPrep; Norgine Pharmaceuticals) versus magnesium citrate (Citramag; Sanochemia UK Ltd.) plus stimulant laxative as bowel preparation for colonoscopy. District General Hospital. Patients attending for day case colonoscopy. Not applicable. Overall cleansing grades of preparations used: patient compliance, taste, and acceptability. A prospective audit of patient experience of taking bowel preparation and blinded colonic scoring assessment of bowel cleansing of each of the tested regimes. A total of 258 (female,138; 53.5%) patients were recruited, 91 in the KleanPrep group (F:45, 49.5%), 86 patients in the Moviprep group (female, 45; 52.3%), and 81 in the Senna/Citramag group (female, 44; 54.3%). Significantly more patients were unable to take the prescribed dose of KleanPrep when compared with the other 2 regimes (19.6%; P<0.0001 vs. Moviprep; P<0.0001 vs. Senna/Citramag). A total of 45.65% of patients reported KleanPrep as tasting unpleasant. This was significantly more than both Moviprep (10.47%; P=0.008) and Senna/Citramag (9.88%; P<0.0001). The overall cleansing efficacy across the 3 groups (those with grades A or B) was 73.9%, 74.5%, and 86.5% for KleanPrep, Moviprep, and Senna/Citramag, respectively. In this series Senna/Citramag proved significantly better at bowel cleansing than KleanPrep (P<0.05) and it showed a trend toward better cleansing when compared with Moviprep (P=0.08). Nonrandomized trial. Split-dosing regime for morning and afternoon lists may have confounded results. In summary, low-volume PEG (Moviprep) and Senna/Citramag combination were better tolerated than large volume PEG with Senna/Citramag providing superior mucosal cleansing.

  19. Restoration of motor function after operative reconstruction of the acutely transected spinal cord in the canine model.

    PubMed

    Liu, Zehan; Ren, Shuai; Fu, Kuang; Wu, Qiong; Wu, Jun; Hou, Liting; Pan, Hong; Sun, Linlin; Zhang, Jian; Wang, Bingjian; Miao, Qing; Sun, Guiyin; Bonicalzi, Vincenzo; Canavero, Sergio; Ren, Xiaoping

    2018-05-01

    Cephalosomatic anastomosis or what has been called a "head transplantation" requires full reconnection of the respective transected ends of the spinal cords. The GEMINI spinal cord fusion protocol has been developed for this reason. Here, we report the first randomized, controlled study of the GEMINI protocol in large animals. We conducted a randomized, controlled study of a complete transection of the spinal cord at the level of T10 in dogs at Harbin Medical University, Harbin, China. These dogs were followed for up to 8 weeks postoperatively by assessments of recovery of motor function, somato-sensory evoked potentials, and diffusion tensor imaging using magnetic resonance imaging. A total of 12 dogs were subjected to operative exposure of the dorsal aspect of the spinal cord after laminectomy and longitudinal durotomy followed by a very sharp, controlled, full-thickness, complete transection of the spinal cord at T10. The fusogen, polyethylene glycol, was applied topically to the site of the spinal cord transection in 7 of 12 dogs; 0.9% NaCl saline was applied to the site of transection in the remaining 5 control dogs. Dogs were selected randomly to receive polyethylene glycol or saline. All polyethylene glycol-treated dogs reacquired a substantial amount of motor function versus none in controls over these first 2 months as assessed on the 20-point (0-19), canine, Basso-Beattie-Bresnahan rating scale (P<.006). Somatosensory evoked potentials confirmed restoration of electrical conduction cranially across the site of spinal cord transection which improved over time. Diffusion tensor imaging, a magnetic resonance permutation that assesses the integrity of nerve fibers and cells, showed restitution of the transected spinal cord with polyethylene glycol treatment (at-injury level difference: P<.02). A sharply and fully transected spinal cord at the level of T10 can be reconstructed with restoration of many aspects of electrical continuity in large animals following the GEMINI spinal cord fusion protocol, with objective evidence of motor recovery and of electrical continuity across the site of transection, opening the way to the first cephalosomatic anastomosis. (Surgery 2017;160:XXX-XXX.). Copyright © 2017. Published by Elsevier Inc.

  20. Facile modulation of cell adhesion to a poly(ethylene glycol) diacrylate film with incorporation of polystyrene nano-spheres.

    PubMed

    Yang, Wenguang; Yu, Haibo; Li, Gongxin; Wang, Yuechao; Liu, Lianqing

    2016-12-01

    Poly(ethylene glycol) diacrylate (PEGDA) is a common hydrogel that has been actively investigated for various tissue engineering applications owing to its biocompatibility and excellent mechanical properties. However, the native PEGDA films are known for their bio-inertness which can hinder cell adhesion, thereby limiting their applications in tissue engineering and biomedicine. Recently, nano composite technology has become a particularly hot topic, and has led to the development of new methods for delivering desired properties to nanomaterials. In this study, we added polystyrene nano-spheres (PS) into a PEGDA solution to synthesize a nano-composite film and evaluated its characteristics. The experimental results showed that addition of the nanospheres to the PEGDA film not only resulted in modification of the mechanical properties and surface morphology but further improved the adhesion of cells on the film. The tensile modulus showed clear dependence on the addition of PS, which enhanced the mechanical properties of the PEGDA-PS film. We attribute the high stiffness of the hybrid hydrogel to the formation of additional cross-links between polymeric chains and the nano-sphere surface in the network. The effect of PS on cell adhesion and proliferation was evaluated in L929 mouse fibroblast cells that were seeded on the surface of various PEGDA-PS films. Cells density increased with a larger PS concentration, and the cells displayed a spreading morphology on the hybrid films, which promoted cell proliferation. Impressively, cellular stiffness could also be modulated simply by tuning the concentration of nano-spheres. Our results indicate that the addition of PS can effectively tailor the physical and biological properties of PEGDA as well as the mechanical properties of cells, with benefits for biomedical and biotechnological applications.

  1. Rapid and sensitive sandwich enzyme-linked immunosorbent assay for detection of staphylococcal enterotoxin B in cheese.

    PubMed Central

    Morissette, C; Goulet, J; Lamoureux, G

    1991-01-01

    A rapid and sensitive screening sandwich enzyme-linked immunosorbent assay (ELISA) was developed for the detection of staphylococcal enterotoxin B (SEB) in cheese by using a highly avid anti-SEB antibody (Ab) as the capture Ab (CAb) and as the biotinylated Ab conjugate. The glutaraldehyde fixation method for the immobilization of CAb on polystyrene dipsticks was superior to the adsorption fixation and the adsorption-glutaraldehyde fixation methods. The glutaraldehyde fixation method resulted in a higher surface-saturating CAb concentration as evaluated by the peroxidase saturation technique and by the ability of the CAb-coated dipstick to discriminate between positive and negative controls (index of discrimination). Of nine blocking agents used alone or in pairs, lysine-human serum albumin, bovine serum albumin, human serum albumin, and gelatin effectively saturated available sites on the CAb-coated dipsticks without causing interference with the antigen-Ab reactions. The addition of 1% polyethylene glycol to the diluent of the biotinylated anti-SEB Ab conjugate improved the detection of SEB. A concentration of 4% polyethylene glycol allowed a 5-min reaction time for the streptavidin-biotin-horseradish peroxidase conjugate. Cheddar cheese homogenate reduced the sensitivity of the SEB assay; however, the sensitivity was restored when 1.6% (wt/vol) of either a nonionic detergent (Mega-9) or two zwitterionic detergents (Zwittergent 3-10 and 3-12 detergent) was added to the diluent. By using the rapid sandwich ELISA, a minimum of 0.5 to 1.0 ng of SEB per ml was detected within 45 min. The whole procedure for the analysis of the cheddar cheese samples was completed within 1 h.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2039234

  2. Effect of Synthetic High Density Lipoproteins Modification with Polyethylene Glycol on Pharmacokinetics and Pharmacodynamics.

    PubMed

    Li, Dan; Fawaz, Maria V; Morin, Emily E; Ming, Ran; Sviridov, Denis; Tang, Jie; Ackermann, Rose; Olsen, Karl; Remaley, Alan T; Schwendeman, Anna

    2018-01-02

    Synthetic high density lipoprotein nanoparticles (sHDLs) capable of mobilizing excess cholesterol from atherosclerotic arteries and delivering it to the liver for elimination have been shown to reduce plaque burden in patients. Unfortunately, sHDLs have a narrow therapeutic index and relative to the endogenous HDL shorter circulation half-life. Surface modification with polyethylene glycol (PEG) was investigated for its potential to extend sHDL circulation in vivo. Various amounts (2.5, 5, and 10%) and different chain lengths (2 and 5 kDa) of PEG-modified lipids were incorporated in sHDL's lipid membrane. Incorporating PEG did not reduce the ability of sHDL to facilitate cholesterol efflux, nor did it inhibit cholesterol uptake by the liver cells. By either adding more PEG or using PEG of longer chain lengths, the circulation half-life was extended. Addition of PEG also increased the area under the curve for the phospholipid component of sHDL (p < 0.05), but not for the apolipoprotein A-I peptide component of sHDL, suggesting sHDL is remodeled by endogenous lipoproteins in vivo. The extended phospholipid circulation led to a higher mobilization of plasma free cholesterol, a biomarker for facilitation of reverse cholesterol transport. The area under the cholesterol mobilization increased about 2-4-fold (p < 0.05), with greater increases observed for longer PEG chains and higher molar percentages of incorporated PEGylated lipids. Mobilized cholesterol was associated primarily with the HDL fraction, led to a transient increase in VLDL cholesterol, and returned to baseline 24 h postdose. Overall, PEGylation of sHDL led to beneficial changes in sHDL particle pharmacokinetic and pharmacodynamic behaviors.

  3. Polyethylene glycol-electrolyte solution (PEG-ES)

    MedlinePlus

    ... electrolytes to prevent dehydration and other serious side effects that may be caused by fluid loss as ... to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in ...

  4. Gd@C82 metallofullerenes for neutron capture therapy—fullerene solubilization by poly(ethylene glycol)-block-poly(2-(N, N-diethylamino)ethyl methacrylate) and resultant efficacy in vitro

    PubMed Central

    Horiguchi, Yukichi; Kudo, Shinpei; Nagasaki, Yukio

    2011-01-01

    Poly(ethylene glycol)-block-poly(2-(N,N-diethylamino)ethyl methacrylate) (PEG-b-PAMA) was found to solubilize fullerenes such as C60, and this technique was applied to metallofullerenes. Gd@C82 was easily dissolved in water in the presence of PEG-b-PAMA without any covalent derivatization, forming a transparent complex about 20–30 nm in diameter. Low cytotoxicity was confirmed in vitro. Neutron irradiation of cultured cells (colon-26 adenocarcinoma) with Gd@C82-PEG-b-PAMA-complexed nanoparticles showed effective cytotoxicity, indicating the effective emission of gamma rays and internal conversion electrons produced from the neutron capture reaction of Gd. This result suggests a potentially valuable approach to gadolinium-based neutron capture therapy. PMID:27877415

  5. In vitro and in vivo evaluation of latex condoms using a two-phase nonoxynol 9 system.

    PubMed

    Rodgers-Neame, N; Duncan, S F; Bradley, E L; Blackwell, R E

    1985-06-01

    In vitro studies were carried out that indicated that a lubricant system consisting of 0.45 +/- 0.1 ml of silicon fluid containing 6.6% +/- 0.5% by volume of nonoxynol 9 and a spermicidal cream consisting of 0.45 +/- 0.1 ml made up of 63.4% polyethylene glycol 400 and 30.0% polyethylene glycol 3350 containing 6.6% +/- 0.5% nonoxynol 9 was effective in reducing sperm motility and viability. This system was tested in vivo with the use of simulated rupture techniques and was found to be equally as effective. Double-blind preference studies were carried out in vivo which showed that the condom system is convenient and comfortable to use, nonirritating to the vagina or urethral mucosa, and esthetically pleasing to the young, reproductive-age population.

  6. Pterygium removal using a polyethylene glycol hydrogel adherent ocular bandage.

    PubMed

    Hirst, Lawrence W

    2013-06-01

    To describe the result of using a polyethylene glycol hydrogel contact lens (ReSure; Ocular Therapeutix, Inc, Bedford, MA) as a protective bandage over denuded areas of Tenons after pterygium removal. Five sequential patients underwent pterygium removal with a conjunctival autograft and painting of bare Tenons in the area of the graft retrieval with a biodegradable polymer, and these patients were followed for 1 year for immediate postoperative pain, epithelial healing, and long-term conjunctival scarring. All patients showed prolonged persistence of the polymer for up to 8 to 10 weeks with resultant increased conjunctival inflammation and scarring with no evidence of decreased postoperative pain. This hydrogel polymer seems to cause prolonged inflammation and resultant scarring when used over extended areas of Tenons, and it has no role in reducing pain after pterygium surgery.

  7. PEGylated anticancer-carbon nanotubes complex targeting mitochondria of lung cancer cells

    NASA Astrophysics Data System (ADS)

    Kim, Sang-Woo; Lee, Yeon Kyung; Lee, Jong Yeon; Hong, Jeong Hee; Khang, Dongwoo

    2017-11-01

    Although activating apoptosis in cancer cells by targeting the mitochondria is an effective strategy for cancer therapy, insufficient targeting of the mitochondria in cancer cells restricts the availability in clinical treatment. Here, we report on a polyethylene glycol-coated carbon nanotube (CNT)-ABT737 nanodrug that improves the mitochondrial targeting of lung cancer cells. The polyethylene glycol-coated CNT-ABT737 nanodrug internalized into the early endosomes via macropinocytosis and clathrin-mediated endocytosis in advance of early endosomal escape and delivered into the mitochondria. Cytosol release of the nanodrug led to apoptosis of lung cancer cells by abruption of the mitochondrial membrane potential, inducing Bcl-2-mediated apoptosis and generating intracellular reactive oxygen species. As such, this study provides an effective strategy for increasing the anti-lung cancer efficacy by increasing mitochondria accumulation rate of cytosol released anticancer nanodrugs.

  8. Synthesis and characterization of polyethylene glycol mediated silver nanoparticles by the green method.

    PubMed

    Shameli, Kamyar; Ahmad, Mansor Bin; Jazayeri, Seyed Davoud; Sedaghat, Sajjad; Shabanzadeh, Parvaneh; Jahangirian, Hossein; Mahdavi, Mahnaz; Abdollahi, Yadollah

    2012-01-01

    The roles of green chemistry in nanotechnology and nanoscience fields are very significant in the synthesis of diverse nanomaterials. Herein, we report a green chemistry method for synthesized colloidal silver nanoparticles (Ag NPs) in polymeric media. The colloidal Ag NPs were synthesized in an aqueous solution using silver nitrate, polyethylene glycol (PEG), and β-D-glucose as a silver precursor, stabilizer, and reducing agent, respectively. The properties of synthesized colloidal Ag NPs were studied at different reaction times. The ultraviolet-visible spectra were in excellent agreement with the obtained nanostructure studies performed by transmission electron microscopy (TEM) and their size distributions. The Ag NPs were characterized by utilizing X-ray diffraction (XRD), zeta potential measurements and Fourier transform infrared (FT-IR). The use of green chemistry reagents, such as glucose, provides green and economic features to this work.

  9. Anaphylactic reaction to polyethylene-glycol conjugated-asparaginase: premedication and desensitization may not be sufficient.

    PubMed

    Sahiner, Umit M; Yavuz, S Tolga; Gökce, Muge; Buyuktiryaki, Betul; Altan, Ilhan; Aytac, Selin; Tuncer, Murat; Tuncer, Ayfer; Sackesen, Cansin

    2013-08-01

    In hypersensitive reactions to native L-asparaginase, either premedication and desensitization or substitution with polyethylene glycol conjugated asparaginase (PEG-ASP) is preferred. Anaphylaxis with PEG-ASP is rare. An 8-year-old girl and a 2.5-year-old boy, both diagnosed as having acute lymphoblastic leukemia, presented with native L-asparaginase hypersensitivity and substitution with PEG-ASP was preferred. They received a premedication (methylprednisolone, hydroxyzine and ranitidine) followed by desensitization with PEG-ASP infusion. Both patients developed anaphylaxis with peg-asparaginase. These are the first reported cases of anaphylactic reaction to PEG-ASP, despite the application of both premedication and desensitization. Anaphylaxis with PEG-ASP is very rare and premedication and desensitization protocols may not prevent these hypersensitive reactions. © 2013 The Authors. Pediatrics International © 2013 Japan Pediatric Society.

  10. Novel Shape-Stabilized Phase Change Materials Composed of Polyethylene Glycol/Nonsurfactant-Templated Mesoporous Silica: Preparation and Thermal Properties

    NASA Astrophysics Data System (ADS)

    Chen, Yan; Zhu, Yingying; Wang, Jinbao; Lv, Mengjiao; Zhang, Xiongjie; Gao, Junkai; Zhang, Zijun; Lei, Hao

    2017-12-01

    A novel shape-stabilized phase change material (PEG/TAMS), fabricated using tannic acid-templated mesoporous silica (TAMS) as a support for polyethylene glycol, was developed for thermal energy storage. The method used to synthesize TAMS was simple, cost effective, environmentally friendly, and free of surfactant. The characterization results indicated that PEG was physically absorbed to TAMS and that TAMS had no influence on the crystal structure of PEG. According to the TGA thermograms, PEG/TAMS has excellent thermal stability and can be applied over a wide temperature range. Additionally, the differential scanning calorimetry results suggested that PEG/TAMS has good thermal properties and that its fusion and solidification enthalpies reached 114.7 J/g and 102.4 J/g, respectively. The results indicated that PEG/TAMS has great potential for practical applications.

  11. Poly(ethylene glycol)/chitosan/sodium glycerophosphate gel replaced the joint capsule with slow-release lubricant after joint surgery.

    PubMed

    Lu, Hailin; Ren, Shanshan; Li, Xing; Guo, Junde; Dong, Guangneng; Li, Jianhui; Gao, Li

    2018-08-01

    Body fluid is normally the only lubricant after joint replacement surgery, but wear problems have occurred because body fluid has poor lubrication ability. However, traditional lubricant would be diluted by body fluids and then absorbed by the human body. Therefore, an injectable gel with the ability to slow-release lubricant was designed to replace the joint capsule. The proposed gel, poly(ethylene glycol)/chitosan/sodium glycerophosphate (PEG/CS/GP) composite gel was then tested. The tribology results showed that the PEG/CS/GP gel had excellent slow-release properties, especially under pressure, and the PEG played an important role in improving the gel's rheological and mechanical properties. Moreover, this study revealed that the release solution had a good lubrication effect because the PEG and GP could crosslink via the hydrogen bond effect.

  12. Effect of O/W process parameters on Crataegus azarolus L nanocapsule properties.

    PubMed

    Esmaeili, Akbar; Rahnamoun, Soraya; Sharifnia, Fariba

    2013-05-29

    Nanocapsules have many applications in the drug, cosmetic, fragrance, and food industries. In this study, Crataegus azarolus L. nanocapsules were prepared by a modified emulsion diffusion technique. In this technique a shell was first made from the polyester triblock copolymer poly(ethylene glycol)-poly(butylene adipate)-poly(ethylene glycol) (PEG-PBA-PEG) and then olive oil was set as the core of the nanocapsule by a method known as the polymer deposition solvent evaporation method. Varying amounts of C. azarolus extract, polymer, and olive oil were mixed in acetone and then added to water on a shaker. Finally, the acetone was removed by vacuuming. The size of the prepared nanocapsules were measured with a particle size analysis report (PSAR) and identified by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR). Our experiments showed that the size of the nanocapsules depends on the preparation conditions, i.e., the ratio of polymer to oil and concentrations of polymer and plant extract. A ratio of 1:0.25 polymer to oil was shown to be more suitable for the formation of smaller nanocapsules of C. azarolus.

  13. Effect of O/W process parameters on Crataegus azarolus L nanocapsule properties

    PubMed Central

    2013-01-01

    Background Nanocapsules have many applications in the drug, cosmetic, fragrance, and food industries. In this study, Crataegus azarolus L. nanocapsules were prepared by a modified emulsion diffusion technique. Methods In this technique a shell was first made from the polyester triblock copolymer poly(ethylene glycol)-poly(butylene adipate)-poly(ethylene glycol) (PEG-PBA-PEG) and then olive oil was set as the core of the nanocapsule by a method known as the polymer deposition solvent evaporation method. Varying amounts of C. azarolus extract, polymer, and olive oil were mixed in acetone and then added to water on a shaker. Finally, the acetone was removed by vacuuming. Results The size of the prepared nanocapsules were measured with a particle size analysis report (PSAR) and identified by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR). Conclusions Our experiments showed that the size of the nanocapsules depends on the preparation conditions, i.e., the ratio of polymer to oil and concentrations of polymer and plant extract. A ratio of 1:0.25 polymer to oil was shown to be more suitable for the formation of smaller nanocapsules of C. azarolus. PMID:23718829

  14. Optimization of Serine Protease Purification from Mango (Mangifera indica cv. Chokanan) Peel in Polyethylene Glycol/Dextran Aqueous Two Phase System

    PubMed Central

    Mehrnoush, Amid; Mustafa, Shuhaimi; Sarker, Md. Zaidul Islam; Yazid, Abdul Manap Mohd

    2012-01-01

    Mango peel is a good source of protease but remains an industrial waste. This study focuses on the optimization of polyethylene glycol (PEG)/dextran-based aqueous two-phase system (ATPS) to purify serine protease from mango peel. The activity of serine protease in different phase systems was studied and then the possible relationship between the purification variables, namely polyethylene glycol molecular weight (PEG, 4000–12,000 g·mol−1), tie line length (−3.42–35.27%), NaCl (−2.5–11.5%) and pH (4.5–10.5) on the enzymatic properties of purified enzyme was investigated. The most significant effect of PEG was on the efficiency of serine protease purification. Also, there was a significant increase in the partition coefficient with the addition of 4.5% of NaCl to the system. This could be due to the high hydrophobicity of serine protease compared to protein contaminates. The optimum conditions to achieve high partition coefficient (84.2) purification factor (14.37) and yield (97.3%) of serine protease were obtained in the presence of 8000 g·mol−1 of PEG, 17.2% of tie line length and 4.5% of NaCl at pH 7.5. The enzymatic properties of purified serine protease using PEG/dextran ATPS showed that the enzyme could be purified at a high purification factor and yield with easy scale-up and fast processing. PMID:22489172

  15. Optimization of serine protease purification from mango (Mangifera indica cv. Chokanan) peel in polyethylene glycol/dextran aqueous two phase system.

    PubMed

    Mehrnoush, Amid; Mustafa, Shuhaimi; Sarker, Md Zaidul Islam; Yazid, Abdul Manap Mohd

    2012-01-01

    Mango peel is a good source of protease but remains an industrial waste. This study focuses on the optimization of polyethylene glycol (PEG)/dextran-based aqueous two-phase system (ATPS) to purify serine protease from mango peel. The activity of serine protease in different phase systems was studied and then the possible relationship between the purification variables, namely polyethylene glycol molecular weight (PEG, 4000-12,000 g·mol(-1)), tie line length (-3.42-35.27%), NaCl (-2.5-11.5%) and pH (4.5-10.5) on the enzymatic properties of purified enzyme was investigated. The most significant effect of PEG was on the efficiency of serine protease purification. Also, there was a significant increase in the partition coefficient with the addition of 4.5% of NaCl to the system. This could be due to the high hydrophobicity of serine protease compared to protein contaminates. The optimum conditions to achieve high partition coefficient (84.2) purification factor (14.37) and yield (97.3%) of serine protease were obtained in the presence of 8000 g·mol(-1) of PEG, 17.2% of tie line length and 4.5% of NaCl at pH 7.5. The enzymatic properties of purified serine protease using PEG/dextran ATPS showed that the enzyme could be purified at a high purification factor and yield with easy scale-up and fast processing.

  16. Combined low-volume polyethylene glycol solution plus stimulant laxatives versus standard-volume polyethylene glycol solution: A prospective, randomized study of colon cleansing before colonoscopy

    PubMed Central

    Hookey, Lawrence C; Depew, William T; Vanner, Stephen J

    2006-01-01

    INTRODUCTION The effectiveness of polyethylene glycol solutions (PEG) for colon cleansing is often limited by the inability of patients to drink adequate portions of the 4 L solution. The aim of the present study was to determine whether a reduced volume of PEG combined with stimulant laxatives would be better tolerated and as or more effective than the standard dose. METHODS Patients undergoing outpatient colonoscopy were randomly assigned to receive either low-volume PEG plus sennosides (120 mg oral sennosides syrup followed by 2 L PEG) or the standard volume preparation (4 L PEG). The subjects rated the tolerability of the preparations and their symptoms. Colonoscopists were blind to the colonic cleansing preparation and graded the cleansing efficacy using a validated tool (the Ottawa scale). RESULTS The low-volume PEG plus sennosides preparation was significantly better tolerated than the standard large volume PEG (P<0.001) but was less efficacious (P=0.03). Thirty-eight per cent of patients in the large volume PEG group were unable to finish the preparation, compared with only 6% in the reduced volume group. There were no adverse events reported. CONCLUSIONS Although the low-volume PEG plus sennosides preparation was better tolerated, it was not as effective as standard large-volume PEG. However, in view of the significant difference in tolerance, further research investigating possible improvements in the reduced-volume regimen seems warranted. PMID:16482236

  17. Uptake of Semivolatile Secondary Organic Aerosol Formed from α-Pinene into Nonvolatile Polyethylene Glycol Probe Particles.

    PubMed

    Ye, Penglin; Ding, Xiang; Ye, Qing; Robinson, Ellis S; Donahue, Neil M

    2016-03-10

    Semivolatile organic compounds (SVOCs) play an essential role in secondary organic aerosol (SOA) formation, chemical aging, and mixing of organic aerosol (OA) from different sources. Polyethylene glycol (PEG400) particles are liquid, polar, and nearly nonvolatile; they provide a new vehicle to study the interaction between SVOCs with OA. With a unique fragment ion C4H9O2(+) (m/z 89), PEG400 can be easily separated from α-pinene SOA in aerosol mass spectra. By injecting separately prepared PEG probe particles into a chamber containing SOA coated on ammonium sulfate seeds, we show that a substantial pool of SVOCs exists in equilibrium with the original SOA particles. Quantitative findings are based on bulk mass spectra, size-dependent composition, and the evolution of individual particle mass spectra, which we use to separate the two particle populations. We observed a larger fraction of SVOC vapors with increased amounts of reacted α-pinene. For the same amount of reacted α-pinene, the SOA formed from α-pinene oxidized by OH radicals had a higher fraction of SOA vapors than SOA formed by α-pinene ozonolysis. Compared to the PEG400 probe particles, we observed a lower mass fraction of SVOCs in poly(ethylene glycol) dimethyl ether (MePEG500) probe particles under otherwise identical conditions; this may be due to the lower polarity of the MePEG500 or caused by esterification reactions between the PEG400 and organic acids in the SOA.

  18. Neurite extension and neuronal differentiation of human induced pluripotent stem cell derived neural stem cells on polyethylene glycol hydrogels containing a continuous Young's Modulus gradient.

    PubMed

    Mosley, Matthew C; Lim, Hyun Ju; Chen, Jing; Yang, Yueh-Hsun; Li, Shenglan; Liu, Ying; Smith Callahan, Laura A

    2017-03-01

    Mechanotransduction in neural cells involves multiple signaling pathways that are not fully understood. Differences in lineage and maturation state are suggested causes for conflicting reports on neural cell mechanosensitivity. To optimize matrices for use in stem cell therapy treatments transplanting human induced pluripotent stem cell derived neural stem cells (hNSC) into lesions after spinal cord injury, the effects of Young's Modulus changes on hNSC behavior must be understood. The present study utilizes polyethylene glycol hydrogels containing a continuous gradient in Young's modulus to examine changes in the Young's Modulus of the culture substrate on hNSC neurite extension and neural differentiation. Changes in the Young's Modulus of the polyethylene glycol hydrogels was found to affect neurite extension and cellular organization on the matrices. hNSC cultured on 907 Pa hydrogels were found to extend longer neurites than hNSC cultured on other tested Young's Moduli hydrogels. The gene expression of β tubulin III and microtubule-associated protein 2 in hNSC was affected by changes in the Young's Modulus of the hydrogel. The combinatory method approach used in the present study demonstrates that hNSC are mechanosensitive and the matrix Young's Modulus should be a design consideration for hNSC transplant applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 824-833, 2017. © 2016 Wiley Periodicals, Inc.

  19. Nanoparticles of Poly(Lactide-Co-Glycolide)-d-a-Tocopheryl Polyethylene Glycol 1000 Succinate Random Copolymer for Cancer Treatment

    NASA Astrophysics Data System (ADS)

    Ma, Yuandong; Zheng, Yi; Liu, Kexin; Tian, Ge; Tian, Yan; Xu, Lei; Yan, Fei; Huang, Laiqiang; Mei, Lin

    2010-07-01

    Cancer is the leading cause of death worldwide. Nanomaterials and nanotechnologies could provide potential solutions. In this research, a novel biodegradable poly(lactide-co-glycolide)-d-a-tocopheryl polyethylene glycol 1000 succinate (PLGA-TPGS) random copolymer was synthesized from lactide, glycolide and d-a-tocopheryl polyethylene glycol 1000 succinate (TPGS) by ring-opening polymerization using stannous octoate as catalyst. The obtained random copolymers were characterized by 1H NMR, FTIR, GPC and TGA. The docetaxel-loaded nanoparticles made of PLGA-TPGS copolymer were prepared by a modified solvent extraction/evaporation method. The nanoparticles were then characterized by various state-of-the-art techniques. The results revealed that the size of PLGA-TPGS nanoparticles was around 250 nm. The docetaxel-loaded PLGA-TPGS nanoparticles could achieve much faster drug release in comparison with PLGA nanoparticles. In vitro cellular uptakes of such nanoparticles were investigated by CLSM, demonstrating the fluorescence PLGA-TPGS nanoparticles could be internalized by human cervix carcinoma cells (HeLa). The results also indicated that PLGA-TPGS-based nanoparticles were biocompatible, and the docetaxel-loaded PLGA-TPGS nanoparticles had significant cytotoxicity against Hela cells. The cytotoxicity against HeLa cells for PLGA-TPGS nanoparticles was in time- and concentration-dependent manner. In conclusion, PLGA-TPGS random copolymer could be acted as a novel and promising biocompatible polymeric matrix material applicable to nanoparticle-based drug delivery system for cancer chemotherapy.

  20. Dual-Functional Polyethylene Glycol-b-polyhexanide Surface Coating with in Vitro and in Vivo Antimicrobial and Antifouling Activities.

    PubMed

    Zhi, Zelun; Su, Yajuan; Xi, Yuewei; Tian, Liang; Xu, Miao; Wang, Qianqian; Padidan, Sara; Li, Peng; Huang, Wei

    2017-03-29

    In recent years, microbial colonization on the surface of biomedical implants/devices has become a severe threat to human health. Herein, surface-immobilized guanidine derivative block copolymers create an antimicrobial and antifouling dual-functional coating. We report the preparation of an antimicrobial and antifouling block copolymer by the conjugation of polyhexanide (PHMB) with either allyl glycidyl ether or allyloxy polyethylene glycol (APEG; MW 1200 and 2400). The allyl glycidyl ether modified PHMB (A-PHMB) and allyloxy polyethylene glycol 1200/2400 modified PHMB (APEG 1200/2400 -PHMB) copolymers were grafted onto a silicone rubber surface as a bottlebrush-like coating, respectively, using a plasma-UV-assisted surface-initiated polymerization. Both A-PHMB and APEG 1200/2400 -PHMB coatings exhibited excellent broad-spectrum antimicrobial properties against Gram-negative/positive bacteria and fungi. The APEG 2400 -PHMB coating displayed an improved antibiofilm as well as antifouling properties and a long reusable cycle, compared with two other coatings, due to its abundant PEG blocks among those copolymers. Also, the APEG 2400 -PHMB-coated silicone coupons were biocompatible toward mammalian cells, as revealed by in vitro hemocompatibile and cytotoxic assays. An in vivo study showed a significant decline of Escherichia coli colonies with a 5-log reduction, indicating the APEG 2400 -PHMB coating surface worked effectively in the rodent subcutaneous infection model. This PHMB-based block copolymer coating is believed to be an effective strategy to prevent biomaterial-associated infections.

  1. [Study on self-microemulsifying membrane controlled-release drop pill of hawthorn leaves flavonoids].

    PubMed

    Wang, Jin-Xuan; Huang, Hong-Zhang; Li, Ning; Gao, Chong-Kai

    2014-03-01

    To prepare the hawthorn leaves flavonoids self-microemulsifying membrane controlled-release coated drop pill, and to study its release rate in vitro and pharmacokinetics study in vivo. In order to improve the dissolution of hawthorn leaves flavonoids, self-microemulsifying technology was used to prepare the hawthorn leaves flavonoids self-microemulsion. Hawthorn leaves flavonoids self-microemulsifying drop pill was prepared with the PEG 6000. Studies were made on the in vitro release of flavonoids from hawthorn leaves self-micro-emulsifying membrane-moderated coated drop pills and the in vivo pharmacokinetic in rats. The prescription of flavonoids from hawthorn leaves self-micro-emulsifying drop pills was 0.25 g of flavonoids from hawthorn leaves, 0.25 g of iodophenyl maleimide, 0.375 g of polyethylene glycol 400, 0.375 g of cremophor RH 40 and 2 g of polyethylene glycol 6000. The optimized prescription was 4 g of ethyl cellulose 20, 0.64 g of polyethylene glycol 400, 1.8 g of diethyl phthalate, and the weight of coating materials increased by 3.5%. Flavonoids from hawthorn leaves self-micro-emulsifying membrane-moderated coated drop pills complied with the design of sustained-release in 12 h in terms of in vitro release and in vivo pharmacokinetic parameters in rats, and its bioavailability was 2.47 times of quick-release drop pills. Slightly soluble flavonoids from hawthorn leaves could be made into sustained-release preparations by the self-micro-emulsifying and coating technology.

  2. Fabrication of biodegradable micelles with sheddable poly(ethylene glycol) shells as the carrier of 7-ethyl-10-hydroxy-camptothecin.

    PubMed

    Guo, Qian; Luo, Ping; Luo, Yu; Du, Fang; Lu, Wei; Liu, Shiyuan; Huang, Jin; Yu, Jiahui

    2012-12-01

    Biodegradable micelles with sheddable poly(ethylene glycol) shells were fabricated based on poly(ethylene glycol)-block-poly(γ-benzyl L-glutamate) (mPEG-SS-PBLG) diblock copolymer and applied as the carrier of 7-ethyl-10-hydroxy-camptothecin (SN-38) in order to enhance its solubility and stability in aqueous media. The diblock polymer was designed to have the hydrophilic PEG moiety and hydrophobic PBLG moiety linked by biodegradable disulfide bond, so in reducing environment the PEG shells can be detached. The polymer was able to form the micelles of nano-scale in aqueous media, suggesting their passive targeting potential to tumor tissue. Water-insoluble antitumor drug, SN-38, was easily encapsulated into mPEG-SS-PBLG nanomicelles by lyophilization method. When setting theoretical drug loading content at 10 wt%, the drug encapsulation efficiency (EE) was assayed as 73.5%. Owing to the disulfide bond in mPEG-SS-PBLG, intense release of SN-38 occurred in the presence of dithiothreitol (DTT) at the concentration of simulating the intracellular condition, however, micelles showed gradual release of SN-38 in the absence of DTT. Also, the mPEG-SS-PBLG micelles effectively protected the active lactone ring of SN-38 from hydrolysis under physiological condition. Compared with free SN-38, SN-38-loaded nanomicelles showed essentially decreased cytotoxicity against L929 cell line in 24h, bare mPEG-SS-PBLG nanomicelles showed almost non-toxicity. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Regulating the surface poly(ethylene glycol) density of polymeric nanoparticles and evaluating its role in drug delivery in vivo.

    PubMed

    Du, Xiao-Jiao; Wang, Ji-Long; Liu, Wei-Wei; Yang, Jin-Xian; Sun, Chun-Yang; Sun, Rong; Li, Hong-Jun; Shen, Song; Luo, Ying-Li; Ye, Xiao-Dong; Zhu, Yan-Hua; Yang, Xian-Zhu; Wang, Jun

    2015-11-01

    Poly(ethylene glycol) (PEG) is usually used to protect nanoparticles from rapid clearance in blood. The effects are highly dependent on the surface PEG density of nanoparticles. However, there lacks a detailed and informative study in PEG density and in vivo drug delivery due to the critical techniques to precisely control the surface PEG density when maintaining other nano-properties. Here, we regulated the polymeric nanoparticles' size and surface PEG density by incorporating poly(ε-caprolactone) (PCL) homopolymer into poly(ethylene glycol)-block-poly(ε-caprolactone) (PEG-PCL) and adjusting the mass ratio of PCL to PEG-PCL during the nanoparticles preparation. We further developed a library of polymeric nanoparticles with different but controllable sizes and surface PEG densities by changing the molecular weight of the PCL block in PEG-PCL and tuning the molar ratio of repeating units of PCL (CL) to that of PEG (EG). We thus obtained a group of nanoparticles with variable surface PEG densities but with other nano-properties identical, and investigated the effects of surface PEG densities on the biological behaviors of nanoparticles in mice. We found that, high surface PEG density made the nanoparticles resistant to absorption of serum protein and uptake by macrophages, leading to a greater accumulation of nanoparticles in tumor tissue, which recuperated the defects of decreased internalization by tumor cells, resulting in superior antitumor efficacy when carrying docetaxel. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Polyethylene glycol grafted polyethylene: a versatile platform for nonmigratory active packaging applications.

    PubMed

    Barish, Jeffrey A; Goddard, Julie M

    2011-01-01

    Nonmigratory active packaging, in which bioactive components are tethered to the package, offers the potential to reduce the need for additives in food products while maintaining safety and quality. A challenge in developing nonmigratory active packaging materials is the loss of biomolecular activity that can occur when biomolecules are immobilized. In this work, we describe a method in which a biocompatible polymer (polyethylene glycol, PEG) is grafted from the surface of ozone-treated low-density polyethylene (LDPE) resulting in a surface functionalized polyethylene to which a range of amine-terminated bioactive molecules can be immobilized. Free radical graft polymerization is used to graft PEG onto the LDPE surface, followed by immobilization of ethylenediamine onto the PEG tether. Ethylenediamine was used to demonstrate that amine-terminated molecules could be covalently attached to the PEG-grafted film. Changes in surface chemistry and topography were measured by attenuated total reflectance Fourier transform infrared spectroscopy, contact angle, atomic force microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. We demonstrate the ability to graft PEG onto the surface of polymer packaging films by free radical graft polymerization, and to covalently link an amine-terminated molecule to the PEG tether, demonstrating that amine-terminated bioactive compounds (such as peptides, enzymes, and some antimicrobials) can be immobilized onto PEG-grafted LDPE in the development of nonmigratory active packaging.   Nonmigratory active packaging offers the potential for improving food safety and quality while minimizing the migration of the active agent into food. In this paper, we describe a technique to modify polyethylene packaging films such that active agents can be covalently immobilized by a biocompatible tether. Such a technique can be adapted to a number of applications such as antimicrobial, antioxidant, or immobilized enzyme active packaging. © 2011 Institute of Food Technologists®

  5. Polar stationary phases based on poly(oligo ethylene glycol)diacrylates for capillary gas chromatography

    NASA Astrophysics Data System (ADS)

    Shiryaeva, V. E.; Popova, T. P.; Korolev, A. A.; Kanat'eva, A. Yu.; Kurganov, A. A.

    2017-08-01

    New stationary phases for capillary columns in GC are synthesized and studied. The phases are prepared by depositing oligo(ethylene glycol)diacrylates on the column walls and subsequent polymerization (crosslinking) in the presence of peroxide initiators. It is shown that stationary phases based on monomers with molecular weights of 10 kDa or higher exhibit separation properties similar to those of conventional stationary phases based on polyethylene glycol (PEG); however, their thermal stability is higher because they have a higher degree of crosslinking and a more ordered structure of the crosslinked polymers than the respective parameters of phases based on native PEG.

  6. Biodegradable Poly (Lactic-co-Glycolic Acid)-Polyethylene Glycol Nanocapsules: An Efficient Carrier for Improved Solubility, Bioavailability, and Anticancer Property of Lutein.

    PubMed

    Arunkumar, Ranganathan; Prashanth, Keelara Veerappa Harish; Manabe, Yuki; Hirata, Takashi; Sugawara, Tatsuya; Dharmesh, Shylaja Mallaiah; Baskaran, Vallikannan

    2015-06-01

    Lutein bioavailability is limited because of its poor aqueous solubility. In this study, lutein-poly (lactic-co-glycolic acid) (PLGA)-polyethylene glycol (PEG) nanocapsules were prepared to improve the solubility, bioavailability, and anticancer property of lutein. The scanning electron microscopy and dynamic light scattering examination revealed that the nanocapsules are smooth and spherical with size ranging from 80 to 500 nm (mean = 200 nm). In vitro lutein release profile from nanocapsules showed controlled sustainable release (66%) up to 72 h. Aqueous solubility of lutein nanocapsules was much higher by 735-fold than the lutein. Fourier transform infrared spectroscopy analyses showed no chemical interaction among PLGA, PEG, and lutein, indicating possible weak intermolecular forces like hydrogen bonds. X-ray diffraction revealed lutein is distributed in a disordered amorphous state in nanocapsules. Postprandial plasma kinetics (area under the curve) of an oral dose of lutein from nanocapsules was higher by 5.4-fold compared with that of micellar lutein (control). The antiproliferative effect of lutein from nanocapsules (IC50 value, 10.9 μM) was higher (43.6%) than the lutein (IC50 value, 25 μM). Results suggest that PLGA-PEG nanocapsule is an efficient carrier for enhancing hydrophilicity, bioavailability, and anticancer property of lipophilic molecules such as lutein. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  7. Hierarchical porous silicon carbide with controlled micropores and mesopores for electric double layer capacitors

    NASA Astrophysics Data System (ADS)

    Kim, Myeongjin; Oh, Ilgeun; Kim, Jooheon

    2015-05-01

    Three-dimensional hierarchical micro and mesoporous silicon carbide spheres (MMPSiC) are prepared by the template method and carbonization reaction via the aerosol spray drying method. The mesopores are generated by the self-assembly of the structure-directing agents, whereas the micropores are derived from the partial evaporation of Si atoms during carbonization. To investigate the effect of mesopore size on electrochemical performance, three types of MMPSiC with different mesopore size were fabricated by using three different structure directing agents (cetyltriethylammonium bromide (CTAB), Polyethylene glycol hexadecyl ether (Brij56), and Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123)). The MMPSiC electrode prepared with Brij56 exhibits the highest charge storage capacity with a specific capacitance of 253.7 F g-1 at a scan rate of 5 mV s-1 and 87.9% rate performance from 5 to 500 mV s-1 in 1 M Na2SO4 aqueous electrolyte. The outstanding electrochemical performance might be because of the ideal mesopore size, which effectively reduces the resistant pathways for ion diffusion in the pores and provides a large accessible surface area for ion transport/charge storage. These encouraging results demonstrate that the MMPSiC prepared with Brij56 is a promising candidate for high performance electrode materials for supercapacitors.

  8. Assessment of toxicity and tolerability of a combination vehicle; 5% Pharmasolve, 45% Propylene glycol and 50% Polyethylene glycol 400 in rats following repeated intravenous administration.

    PubMed

    Pandey, Santosh Kumar; Goyal, Vinod Kumar; Nalge, Prashant; Are, Purnachander; Vincent, Sthevaan; Nirogi, Ramakrishna

    2017-12-01

    The selection of a suitable vehicle for administration of NCEs in non-clinical studies is always a challenge for poorly soluble compounds. Challenge is increased if the dose formulation is intended for intravenous (i.v.) administration where isotonic, biologically compatible pH and solution form is an absolute requirement. Vehicle toxicity and tolerability data are not readily available for a number of combination vehicles therefore, an i.v. tolerability studies was planned in rats with 5% v/v Pharmasolve (NMP), 45% v/v Propylene glycol (PG) and 50% v/v Polyethylene glycol (PEG) 400 combination, at dose volume of 0.5, 1, 2 and 5 mL/kg body weight for 28 days. The vehicle combination was administered via lateral tail vein and effects on clinical signs, body weights, feed consumption, clinical pathology and histopathology were evaluated. Clinical signs of toxicity like tremors, convulsions and death were noticed at 5 mL/kg during the course of the study. At 2 mL/kg, injection site injury without systemic toxicity was noticed. In conclusion, 1 mL/kg of a combination vehicle of 5% NMP, 45% PG and 55% PEG 400 can be administered intravenously once-a-day up to 28 days without any discomfort or injury to rats. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Effects of polyethylene glycol and a synthetic ice blocker during vitrification of immature porcine oocytes on survival and subsequent embryo development.

    PubMed

    Santos, Elisa Caroline da Silva; Somfai, Tamas; Appeltant, Ruth; Dang-Nguyen, Thanh Quang; Noguchi, Junko; Kaneko, Hiroyuki; Kikuchi, Kazuhiro

    2017-08-01

    We evaluated the effects of polyethylene glycol (PEG) and Supercool X-1000 (SC) as supplements during the vitrification of immature cumulus-enclosed porcine oocytes in a solution based on 17.5% ethylene glycol + 17.5% propylene glycol. After warming, the oocytes were subjected to in vitro maturation, fertilization and embryo culture. In Experiment 1, equilibration and vitrification solutions were supplemented with or without 2% (w/v) PEG (PEG+ and PEG-, respectively). The survival rate, cleavage and blastocyst development were similar between PEG+ and PEG- groups; however, all values were lower than those in the non-vitrified control. In Experiment 2, vitrification solution was supplemented with or without 1% (v/v) SC (SC+ and SC-, respectively). The percentages of survival and blastocyst development were similar between SC+ and SC- groups but lower than those in the non-vitrified control. The percentage of cleavage in the SC- group was significantly lower than the control and the SC+ groups, which were in turn similar to one another. In both experiments, the cell numbers in blastocysts were not significantly different among the non-vitrified and vitrified groups. In conclusion, PEG did not improve oocyte survival and embryo development, whereas SC improved the ability of surviving oocytes to cleave but not to develop into blastocysts. © 2016 Japanese Society of Animal Science.

  10. Biologically engineered protein-graft-poly(ethylene glycol) hydrogels: A cell-adhesive and plasmin-degradable biosynthetic material for tissue repair

    NASA Astrophysics Data System (ADS)

    Halstenberg, Sven

    2002-01-01

    The goal of the research presented in this dissertation was to create a biomimetic artificial material that exhibits functions of extracellular matrix relevant for improved nerve regeneration. Neural adhesion peptides were photoimmobilized on highly crosslinked poly(ethylene glycol)-based substrates that were otherwise non-adhesive. Neurons adhered in two-dimensional patterns for eleven hours, but no neurites extended. To enable neurite extension and nerve regeneration in three dimensions, and to address the need for specifically cell adhesive and cell degradable materials for clinical applications in tissue repair in general, an artificial protein was recombinantly expressed and purified that consisted of a repeating amino acid sequence based on fibrinogen and anti-thrombin III. The recombinant protein contained integrin-binding RGD sites, plasmin degradation sites, heparin binding sites, and six thiol-containing cysteine residues as grafting sites for poly(ethylene glycol) diacrylate via Michael-type conjugate addition. The resulting protein-graft-poly(ethylene glycol)acrylates were crosslinked by photopolymerization to form hydrogels. Although three-dimensional, RGD mediated and serine protease-dependent ingrowth of human fibroblasts into protein-graft-poly(ethylene glycol) hydrogels occurred, only surface neurite outgrowth was observed from chick dorsal root ganglia. Axonal outgrowth depended on the concentration of matrix-bound heparin, suggesting that improved mechanical strength of the hydrogels and possible immobilization of neuroactive factors due to the presence of heparin promoted neurite outgrowth. Together, the above results show that specific biological functions can be harnessed by protein-graft-poly(ethylene glycol) hydrogels to serve as matrices for tissue repair and regeneration. In particular, the two design objectives, specific cell adhesion and degradability by cell-associated proteases, were fulfilled by the material. In the future, this and similar artificial protein-graft-poly(ethylene glycol) materials with varying protein elements for improved wound healing might serve as biosynthetic implant materials or wound dressings that degrade in synchrony with the formation of a variety of target tissues.

  11. Effects of polyalkylene glycols and fatty acid soaps on properties of synthetic lubricating-cooling fluids

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stulii, A.A.

    1983-01-01

    The lack of any effect of the polyalkylene glycols on the series of properties of the fatty acid soaps was confirmed by replacing the PEG-35 in the synthetic lubricating-cooling fluid (LCF) by a polyethylene glycol with a molecular weight of 400 or 6000, a propylene oxide oligomer with a molecular weight of 700, or a copolymer of ethylene and propylene oxides (Pluronic 44, Pluriol PE-6400, Hydropol 200). Attempts to select surfactants and optimal concentrations in synthetic LCFs based on polyalkylene glycols. Indicates that of the studied soaps, those of the most interest are the triethanolamine soaps of individual C/sub 6/-C/submore » 10/ fatty acids and commercial mixed C/sub 7/-C/sub 9/ synthetic fatty acids. Finds that the polyalkylene glycols and the indicated soaps supplement each other, imparting the required set of properties to the LCF.« less

  12. Molecular mechanism of gelation with ethylene glycol added to a solution of polyacrylonitrile in dimethylsulfoxide

    NASA Astrophysics Data System (ADS)

    Vettegren', V. I.; Machalaba, N. N.; Zharov, V. B.; Kulik, V. B.; Savitskii, A. V.

    2011-06-01

    The mechanism of solidifying a solution of polyacrylonitrile (PAN) in dimethylsulfoxide (DMSO) into which ethylene glycol is added is studied by the method of Raman spectroscopy. In the absence of ethylene glycol, DMSO molecules produce dipole-dipole bonds to PAN molecules. Upon adding ethylene glycol, DMSO molecules form hydrogen bonds with it and a line at 1000 cm-1 appears in the Raman spectrum, which is assigned to the valence vibrations of S=O bonds involved in the hydrogen bonds. After DMSO is removed, ethylene glycol molecules produce hydrogen bonds with two neighboring PAN molecules, giving rise to a band at 2264 cm-1, which is assigned to the valence vibrations of C≡N bonds involved in these hydrogen bonds. A high-viscosity gel consisting of PAN molecules arises in which these molecules are bonded to each other through ethylene glycol molecules.

  13. Eco-friendly polyethylene glycol promoted Michael addition reactions of α,β-unsaturated carbonyl compounds

    EPA Science Inventory

    Abstract- Intra- and inter-nucleophilic addition reactions of different unsaturated compounds were found to be highly effective without any additives in PEG-400 as a recyclable reaction medium under neutral conditions.

  14. Polyethylene glycol (PEG) assisted size-controlled SnO{sub 2} nanoparticles by sol-gel process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tripathi, P., E-mail: ptrip71@yahoo.com; Ahmed, Ateeq; Ali, Tinku

    2016-05-23

    Tetragonal phase tin oxide (SnO{sub 2}) nanoparticles have been synthesized by sol–gel method using SnCl{sub 4}.5H{sub 2}O and polyethylene glycol (PEG) of different concentration. The phase, size and purity of the final products are characterized by X-ray diffraction (XRD). The morphology is confirmed by scanning electron microscopy (SEM) analysis. There exists relationship between the concentration of PEG and particle size of SnO{sub 2} nanoparticles. Increase in concentration of PEG caused the reduction of particle size of tin oxide nanoparticles. The results suggest that the concentration of PEG plays a significant role in determining the size of SnO{sub 2} nanoparticles synthesizedmore » via this method. The optical property of the product has been explored by Ultraviolet (UV-visible) and Fourier Transform Infrared (FTIR) spectroscopic techniques.« less

  15. Hydrophilicity improvement in polyphenylsulfone nanofibrous filtration membranes through addition of polyethylene glycol

    NASA Astrophysics Data System (ADS)

    Kiani, Shirin; Mousavi, Seyed Mahmoud; Shahtahmassebi, Nasser; Saljoughi, Ehsan

    2015-12-01

    Novel hydrophilic polyphenylsulfone (PPSU) nanofibrous membrane was prepared by electrospinning of the PPSU solution blended with polyethylene glycol 400 (PEG 400). The influence of the PEG concentration on the membrane characteristics was studied using scanning electron microscopy (SEM), water contact angle measurement, and tensile test. Filtration performance of the membranes was investigated by measurement of pure water flux (PWF) and determination of the rejection values of the pollution indices during treatment of canned beans production wastewater. According to the results, blending the PPSU solution with 10 wt.% PEG 400 resulted in formation of a nanofibrous membrane with high porosity and increased mechanical strength which exhibited a low water contact angle of 8.9° and high water flux of 7920 L/m2h. Flux recovery of the mentioned membrane which was assessed by filtration of a solution containing bovine serum albumin (BSA) was 83% indicating a noticeable antifouling property.

  16. Precise measurement of the self-diffusion coefficient for poly(ethylene glycol) in aqueous solution using uniform oligomers

    NASA Astrophysics Data System (ADS)

    Shimada, Kayori; Kato, Haruhisa; Saito, Takeshi; Matsuyama, Shigetomo; Kinugasa, Shinichi

    2005-06-01

    Uniform poly(ethylene glycol) (PEG) oligomers, with a degree of polymerization n =1-40, were separated by preparative supercritical fluid chromatography from commercial monodispersed samples. Diffusion coefficients, D, for separated uniform PEG oligomers were measured in dilute solutions of deuterium oxide (D2O) at 30 ° C, using pulsed-field gradient nuclear magnetic resonance. The measured D for each molecular weight was extrapolated to infinite dilution. Diffusion coefficients obtained at infinite dilution follow the scaling behavior of Zimm-type diffusion, even in the lower molecular weight range. Molecular-dynamics simulations for PEG in H2O also showed this scaling behavior, and reproduced close hydrodynamic interactions between PEG and water. These findings suggest that diffusion of PEG in water is dominated by hydrodynamic interaction over a wide molecular weight range, including at low molecular weights around 1000.

  17. Enhanced hepatic differentiation of human amniotic epithelial cells on polyethylene glycol-linked multiwalled carbon nanotube-coated hydrogels.

    PubMed

    Zhao, Chunyan; Lin, Jamie Siqi; Choolani, Mahesh; Dan, Yock Young; Pastorin, Giorgia; Ho, Han Kiat

    2018-04-26

    Polyethylene glycol-linked multiwalled carbon nanotube-coated poly-acrylamide hydrogel (CNT-PA) was customized to mimic human liver stiffness and nanostructured surface in liver cells for modulating differentiation of human amniotic epithelial cells (hAECs) into functional hepatocyte-like cells (HLCs) in vitro. This composite of CNT-PA matrix enhanced the hepatic differentiation of hAECs into HLCs with suppression of pluripotent markers and up-regulation of hepatic markers at both transcript and protein levels. Furthermore, the HLCs on CNT-PA demonstrated hepatocytic functions in terms of albumin secretion, higher uptake of indocyanine green, and comparable CYP3A4 enzymatic function and inducibility when matched against HepG2 cells. Taken together, CNT-PA provides an efficient and scalable platform for the expansion of HLCs from hAECs and could be explored further for downstream development. Copyright © 2018 John Wiley & Sons, Ltd.

  18. Biodegradable and thermosensitive monomethoxy poly(ethylene glycol)-poly(lactic acid) hydrogel as a barrier for prevention of post-operative abdominal adhesion.

    PubMed

    Fu, Shao Zhi; Li, Zhi; Fan, Jun Ming; Meng, Xiao Hang; Shi, Kun; Qu, Ying; Yang, Ling Lin; Wu, Jing Bo; Fan, Juan; Luot, Feng; Qian, Zhi Yong

    2014-03-01

    Post-operative peritoneal adhesions are serious consequences of abdominal or pelvic surgery and cause severe bowel obstruction, chronic pelvic pain and infertility. In this study, a novel nano-hydrogel system based on a monomethoxy poly(ethylene glycol)-poly(lactic acid) (MPEG-PLA) di-block copolymer was studied for its ability to prevent abdominal adhesion in rats. The MPEG-PLA hydrogel at a concentration of 40% (w/v) was injected and was able to adhere to defect sites at body temperature. The ability of the hydrogel to inhibit adhesion of post-operative tissues was evaluated by utilizing a rat model of abdominal sidewall-cecum abrasion. It was possible to heal wounded tissue through regeneration of neo-peritoneal tissues ten days after surgery. Our data showed that this hydrogel system is equally as effective as current commercialized anti-adhesive products.

  19. Virioplankton 'pegylation': use of PEG (polyethylene glycol) to concentrate and purify viruses in pelagic ecosystems.

    PubMed

    Colombet, J; Robin, A; Lavie, L; Bettarel, Y; Cauchie, H M; Sime-Ngando, T

    2007-12-01

    We have described the use of Polyethylene glycol (PEG) for the precipitation of natural communities of aquatic viruses, and its comparison with the usual concentration method based on ultracentrifugation. Experimental samples were obtained from different freshwater ecosystems whose trophic status varied. Based on transmission electron microscope observations and counting of phage-shaped particles, our results showed that the greatest recovery efficiency for all ecosystems was obtained when we used the PEG protocol. On average, this protocol allowed the recovery of >2-fold more viruses, compared to ultracentrifugation. In addition, the diversity of virioplankton, based on genomic size profiling using pulsed field gel electrophoresis, was higher and better discriminated when we used the PEG method. We conclude that pegylation offers a valid, simple and cheaper alternative method to ultracentrifugation, for the concentration and the purification of pelagic viruses.

  20. One pot synthesis of highly luminescent polyethylene glycol anchored carbon dots functionalized with a nuclear localization signal peptide for cell nucleus imaging.

    PubMed

    Yang, Lei; Jiang, Weihua; Qiu, Lipeng; Jiang, Xuewei; Zuo, Daiying; Wang, Dongkai; Yang, Li

    2015-04-14

    Strong blue fluorescent polyethylene glycol (PEG) anchored carbon nitride dots (CDs@PEG) with a high quantum yield (QY) of 75.8% have been synthesized by a one step hydrothermal treatment. CDs with a diameter of ca. 6 nm are well dispersed in water and present a graphite-like structure. Photoluminescence (PL) studies reveal that CDs display excitation-dependent behavior and are stable under various test conditions. Based on the as-prepared CDs, we designed novel cell nucleus targeting imaging carbon dots functionalized with a nuclear localization signal (NLS) peptide. The favourable biocompatibilities of CDs and NLS modified CDs (NLS-CDs) are confirmed by in vitro cytotoxicity assays. Importantly, intracellular localization experiments in MCF7 and A549 cells demonstrate that NLS-CDs could be internalized in the nucleus and show blue light, which indicates that CDs may serve as cell nucleus imaging probes.

  1. Adsorption of polyethylene glycol (PEG) onto cellulose nano-crystals to improve its dispersity.

    PubMed

    Cheng, Dong; Wen, Yangbing; Wang, Lijuan; An, Xingye; Zhu, Xuhai; Ni, Yonghao

    2015-06-05

    In this work, the adsorption of polyethylene glycol (PEG) onto cellulose nano-crystals (CNC) was investigated for preparing re-dispersible dried CNC. Results showed that the re-dispersity of CNC in water can be significantly enhanced using a PEG1000 dosage of 5wt% (based on the dry weight of CNC). The elemental analysis confirmed the adsorption of PEG onto the CNC surface. Transmission electron microscopy (TEM) was used to characterize the dry powder and indicated that the irreversible agglomeration of CNC after drying was essentially eliminated based on the PEG adsorption concept. Thermo-gravimetric analysis (TGA) and X-ray diffraction (XRD) suggested that CNC crystallinity and thermal stability were not affected by the adsorption of PEG. Thus, the adsorption of PEG has great potential for producing re-dispersible powder CNC. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Photodynamic therapy of tumors with pyropheophorbide-a-loaded polyethylene glycol–poly(lactic-co-glycolic acid) nanoparticles

    PubMed Central

    Liu, Hui; Zhao, Mei; Wang, Jin; Pang, Mingpei; Wu, Zhenzhou; Zhao, Liqing; Yin, Zhinan; Hong, Zhangyong

    2016-01-01

    Photodynamic therapy (PDT) has many advantages in treating cancers, but the lack of ideal photosensitizers continues to be a major limitation restricting the clinical utility of PDT. This study aimed to overcome this obstacle by generating pyropheophorbide-a-loaded polyethylene glycol–poly(lactic-co-glycolic acid) nanoparticles (NPs) for efficient tumor-targeted PDT. The fabricated NPs were efficiently internalized in the mitochondrion by cancer cells, and they efficiently killed cancer cells in a dose-dependent manner when activated with light. Systemically delivered NPs were highly enriched in tumor sites, and completely ablated the tumors in a xenograft KB tumor mouse model when illuminated with 680 nm light (156 mW/cm2, 10 minutes). The results suggested that this tumor-specific NP-delivery system for pyropheophorbide-a has the potential to be used in tumor-targeted PDT. PMID:27729788

  3. Effect of Temperature on the Physico-Chemical Properties of a Room Temperature Ionic Liquid (1-Methyl-3-pentylimidazolium Hexafluorophosphate) with Polyethylene Glycol Oligomer

    PubMed Central

    Wu, Tzi-Yi; Chen, Bor-Kuan; Hao, Lin; Peng, Yu-Chun; Sun, I-Wen

    2011-01-01

    A systematic study of the effect of composition on the thermo-physical properties of the binary mixtures of 1-methyl-3-pentyl imidazolium hexafluorophosphate [MPI][PF6] with poly(ethylene glycol) (PEG) [Mw = 400] is presented. The excess molar volume, refractive index deviation, viscosity deviation, and surface tension deviation values were calculated from these experimental density, ρ, refractive index, n, viscosity, η, and surface tension, γ, over the whole concentration range, respectively. The excess molar volumes are negative and continue to become increasingly negative with increasing temperature; whereas the viscosity and surface tension deviation are negative and become less negative with increasing temperature. The surface thermodynamic functions, such as surface entropy, enthalpy, as well as standard molar entropy, Parachor, and molar enthalpy of vaporization for pure ionic liquid, have been derived from the temperature dependence of the surface tension values. PMID:21731460

  4. Effects of La0.2Ce0.6Eu0.2F3 nanocrystals capped with polyethylene glycol on human pancreatic cancer cells in vitro

    NASA Astrophysics Data System (ADS)

    Withers, Nathan J.; Glazener, Natasha N.; Rivera, Antonio C.; Akins, Brian A.; Armijo, Leisha M.; Plumley, John B.; Cook, Nathaniel C.; Sugar, Jacqueline M.; Chan, Rana; Brandt, Yekaterina I.; Smolyakov, Gennady A.; Heintz, Philip H.; Osiński, Marek

    2013-02-01

    Lanthanide fluoride colloidal nanocrystals offer a way to improve the diagnosis and treatment of cancer through the enhanced absorption of ionizing radiation, in addition to providing visible luminescence. In order to explore this possibility, tests with a kilovoltage therapy unit manufactured by the Universal X-Ray Company were performed to estimate the energy sensitivity of this technique. La0.2Ce0.6Eu0.2F3 nanocrystals capped with polyethylene glycol of molecular weight 6000 were synthesized, suspended in deionized water, and made tolerant to biological ionic pressures by incubation with fetal bovine serum. These nanocrystals were characterized by dynamic light scattering, muffle furnace ashing, and photoluminescence spectroscopy. Clonogenic assays were performed on the cells to assay the cytotoxicity and radiotoxicity of the nanocrystals on the human pancreatic cancer cell line PANC-1, purchased from ATCC.

  5. High Performance Solid Polymer Electrolytes for Rechargeable Batteries: A Self-Catalyzed Strategy toward Facile Synthesis.

    PubMed

    Cui, Yanyan; Liang, Xinmiao; Chai, Jingchao; Cui, Zili; Wang, Qinglei; He, Weisheng; Liu, Xiaochen; Liu, Zhihong; Cui, Guanglei; Feng, Jiwen

    2017-11-01

    It is urgent to seek high performance solid polymer electrolytes (SPEs) via a facile chemistry and simple process. The lithium salts are composed of complex anions that are stabilized by a Lewis acid agent. This Lewis acid can initiate the ring opening polymerization. Herein, a self-catalyzed strategy toward facile synthesis of crosslinked poly(ethylene glycol) diglycidyl ether-based solid polymer electrolyte (C-PEGDE) is presented. It is manifested that the poly(ethylene glycol) diglycidyl ether-based solid polymer electrolyte possesses a superior electrochemical stability window up to 4.5 V versus Li/Li + and considerable ionic conductivity of 8.9 × 10 -5 S cm -1 at ambient temperature. Moreover, the LiFePO 4 /C-PEGDE/Li batteries deliver stable charge/discharge profiles and considerable rate capability. It is demonstrated that this self-catalyzed strategy can be a very effective approach for high performance solid polymer electrolytes.

  6. Arginine-glycine-aspartic acid-polyethylene glycol-polyamidoamine dendrimer conjugate improves liver-cell aggregation and function in 3-D spheroid culture.

    PubMed

    Chen, Zhanfei; Lian, Fen; Wang, Xiaoqian; Chen, Yanling; Tang, Nanhong

    The polyamidoamine (PAMAM) dendrimer, a type of macromolecule material, has been used in spheroidal cell culture and drug delivery in recent years. However, PAMAM is not involved in the study of hepatic cell-spheroid culture or its biological activity, particularly in detoxification function. Here, we constructed a PAMAM-dendrimer conjugate decorated by an integrin ligand: arginine-glycine-aspartic acid (RGD) peptide. Our studies demonstrate that RGD-polyethylene glycol (PEG)-PAMAM conjugates can promote singly floating hepatic cells to aggregate together in a sphere-like growth with a weak reactive oxygen species. Moreover, RGD-PEG-PAMAM conjugates can activate the AKT-MAPK pathway in hepatic cells to promote cell proliferation and improve basic function and ammonia metabolism. Together, our data support the hepatocyte sphere treated by RGD-PEG-PAMAM conjugates as a potential source of hepatic cells for a biological artificial liver system.

  7. Synthesis of Higher Alcohols via Syngas on Cu/Zn/Si Catalysts. Effect of Polyethylene Glycol Content

    NASA Astrophysics Data System (ADS)

    Cui, Rong-Ji; Yan, Xing; Fan, Jin-Chuan; Huang, Wei

    2018-05-01

    Cu/Zn/Si catalysts with different polyethylene glycol (PEG) content were prepared by a complete liquid-phase method, and characterized by XRD, H2-TPR, N2-adsorption, and XPS. The influence of PEG content on the higher alcohols synthesis from syngas was investigated. The results showed that addition of PEG can influence the texture and surface properties of the catalysts, and therefore affect their activity and product distribution. With an increase in PEG content, BET surface area, Cu crystallite size and surface active ingredient content of the catalysts first increased and then decreased, the CO conversion had similar variation tendency. However, the pore volume and pore diameter of the catalyst increased, and the binding energy of the active component and the content of Cu2O decreased, which resulted in higher catalyst selectivity towards higher alcohols. The highest C2+OH selectivity in total alcohols was 60.6 wt %.

  8. Molecular dynamics study of the structure and interparticle interactions of polyethylene glycol-conjugated PAMAM dendrimers.

    PubMed

    Lee, Hwankyu; Larson, Ronald G

    2009-10-08

    We performed molecular dynamics (MD) simulations of one or two copies of polyethylene glycol of molecular weight 550 (PEG550) and 5000 (PEG5000) daltons, conjugated to generation 3 (G3) to 5 (G5) polyamidoamine (PAMAM) dendrimers with explicit water using a coarse-grained model. We found the radii of gyration of these dendrimer-PEG molecules to be close to those measured in experiments by Hedden and Bauer (Hedden , R. C. ; Bauer , B. J. Macromolecules 2003 , 36 , 1829.). Densely grafted PEG ligands (>50% of the dendrimer surface) extend like brushes, with layer thickness in agreement with theory for starlike polymers. Two dendrimer-PEG complexes in the box drift away from each other, indicating that no aggregation is induced by either short or long PEG chains, conflicting with a recent view that the cytotoxicity of some PEGylated particles might be due to particle aggregation for long PEG lengths.

  9. Lubiprostone: clinical applications beyond constipation.

    PubMed

    Kapoor, Shailendra

    2009-03-07

    In comparison to polyethylene glycol, lubiprostone offers other advantages and is increasingly being used as an adjunctive agent in diagnostic as well as management strategies not only in gastroenterology, but in other fields. For instance, lubiprostone exerts beneficial effects in cystic fibrosis tissues. It augments the chloride secretion in these cells by activating non-cystic fibrosis transmembrane regulator (CFTR) secretion of chloride by afflicted respiratory epithelia. Lubiprostone also seems to improve visualization of the gastrointestinal tract during procedures such as colonoscopy. This is especially true if the lubiprostone is administered prior to bowel cleansing with agents such as polyethylene glycol electrolyte (PEG-E). Lubiprostone also enhances and stimulates contraction in colonic as well as gastric muscles and may thus further contribute as a prokinetic agent. Besides these effects, lubiprostone also causes hyperpolarization in other tissues such as uterine muscle cells. This may prove to be of significant clinical benefit in the management of uterine pathologies in the near future.

  10. Lubiprostone: Clinical applications beyond constipation

    PubMed Central

    Kapoor, Shailendra

    2009-01-01

    In comparison to polyethylene glycol, lubiprostone offers other advantages and is increasingly being used as an adjunctive agent in diagnostic as well as management strategies not only in gastroenterology, but in other fields. For instance, lubiprostone exerts beneficial effects in cystic fibrosis tissues. It augmernts the chloride secretion in these cells by activating non-cystic fibrosis transmembrane regulator (CFTR) secretion of chloride by afflicted respiratory epithelia. Lubiprostone also seems to improve visualization of the gastrointestinal tract during procedures such as colonoscopy. This is especially true if the lubiprostone is administered prior to bowel cleansing with agents such as polyethylene glycol electrolyte (PEG-E). Lubiprostone also enhances and stimulates contraction in colonic as well as gastric muscles and may thus further contribute as a prokinetic agent. Besides these effects, lubiprostone also causes hyperpolarization in other tissues such as uterine muscle cells. This may prove to be of significant clinical benefit in the management of uterine pathologies in the near future. PMID:19266613

  11. Multiphoton microscopy guides neurotrophin modification with poly(ethylene glycol) to enhance interstitial diffusion

    NASA Astrophysics Data System (ADS)

    Stroh, Mark; Zipfel, Warren R.; Williams, Rebecca M.; Ma, Shu Chin; Webb, Watt W.; Saltzman, W. Mark

    2004-07-01

    Brain-derived neurotrophic factor (BDNF) is a promising therapeutic agent for the treatment of neurodegenerative diseases. However, the limited distribution of this molecule after administration into the brain tissue considerably hampers its efficacy. Here, we show how multiphoton microscopy of fluorescently tagged BDNF in brain-tissue slices provides a useful and rapid screening method for examining the diffusion of large molecules in tissues, and for studying the effects of chemical modifications-for example, conjugating with polyethylene glycol (PEG)-on the diffusion constant. This single variable, obtained by monitoring short-term diffusion in real time, can be effectively used for rational drug design. In this study on fluorescently tagged BDNF and BDNF-PEG, we identify slow diffusion as a major contributing factor to the limited penetration of BDNF, and demonstrate how chemical modification can be used to overcome this barrier.

  12. Physiologically based pharmacokinetic modeling of polyethylene glycol-coated polyacrylamide nanoparticles in rats.

    PubMed

    Li, Dingsheng; Johanson, Gunnar; Emond, Claude; Carlander, Ulrika; Philbert, Martin; Jolliet, Olivier

    2014-08-01

    Nanoparticles' health risks depend on their biodistribution in the body. Phagocytosis may greatly affect this distribution but has not yet explicitly accounted for in whole body pharmacokinetic models. Here, we present a physiologically based pharmacokinetic model that includes phagocytosis of nanoparticles to explore the biodistribution of intravenously injected polyethylene glycol-coated polyacrylamide nanoparticles in rats. The model explains 97% of the observed variation in nanoparticles amounts across organs. According to the model, phagocytizing cells quickly capture nanoparticles until their saturation and thereby constitute a major reservoir in richly perfused organs (spleen, liver, bone marrow, lungs, heart and kidneys), storing 83% of the nanoparticles found in these organs 120 h after injection. Key determinants of the nanoparticles biodistribution are the uptake capacities of phagocytizing cells in organs, the partitioning between tissue and blood, and the permeability between capillary blood and tissues. This framework can be extended to other types of nanoparticles by adapting these determinants.

  13. Water structure in polyethylene glycols for preservation of wooden artefacts. A NIR-FT-Raman spectroscopic investigation

    NASA Astrophysics Data System (ADS)

    Christensen, M.; Nielsen, O. F.; Jensen, P.; Schnell, U.

    2005-02-01

    The interaction between polyethylene glycol (PEG) and water in mixtures has been investigated with a particular emphasis on the existence of 'free' water with a tetragonal bulk-like water structure. PEG is used in museum preservation of wooden objects, where free water must be avoided due to the danger of further microbial growth, contractile capillary forces and aqueous transport in wooden archaeological artefacts. A NIR-FT-Raman instrument with excitation at 1064 nm was used for this investigation. The OH stretch region around 3200 cm-1 shows changes in intensity with changing water content and the R(νbar)-function was applied in order to observe free water in the 100-300 cm-1 region. Mixtures of PEG and water were investigated with water contents ranging from 0 to 90% volume. It was found that free water appears around 28-32% volume in a PEG 600 mixture.

  14. Synthesis, self-assembly, and drug-loading capacity of well-defined cyclodextrin-centered drug-conjugated amphiphilic A(14)B(7) Miktoarm star copolymers based on poly(epsilon-caprolactone) and poly(ethylene glycol).

    PubMed

    Gou, Peng-Fei; Zhu, Wei-Pu; Shen, Zhi-Quan

    2010-04-12

    Novel drug-conjugated amphiphilic A(14)B(7) miktoarm star copolymers composed of 14 poly(epsilon-caprolactone) (PCL) arms and 7 poly(ethylene glycol) (PEG) arms with beta-cyclodextrin (beta-CD) as core moiety were synthesized by the combination of controlled ring-opening polymerization (CROP) and "click" chemistry. (1)H NMR, FT-IR, and SEC-MALLS analyses confirmed the well-defined A(14)B(7) miktoarm star architecture. These amphiphilic miktoarm star copolymers could self-assemble into multimorphological aggregates in aqueous solution, which were characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Moreover, the drug-loading efficiency and drug-encapsulation efficiency of the drug-conjugated miktoarm star copolymers were higher than those of the corresponding non-drug-conjugated miktoarm star copolymers.

  15. Solubility of Naproxen in Polyethylene Glycol 200 + Water Mixtures at Various Temperatures

    PubMed Central

    Panahi-Azar, Vahid; Soltanpour, Shahla; Martinez, Fleming; Jouyban, Abolghasem

    2015-01-01

    The solubility of naproxen in binary mixtures of polyethylene glycol 200 (PEG 200) + water at the temperature range from 298.0 K to 318.0 K were reported. The combinations of Jouyban-Acree model + van’t Hoff and Jouyban-Acree model + partial solubility parameters were used to predict the solubility of naproxen in PEG 200 + water mixtures at different temperatures. Combination of Jouyban-Acree model with van’t Hoff equation can be used to predict solubility in PEG 200 + water with only four solubility data in mono-solvents. The obtained solubility calculation errors vary from ~ 17 % up to 35 % depend on the number of required input data. Non-linear enthalpy-entropy compensation was found for naproxen in the investigated solvent system and the Jouyban−Acree model provides reasonably accurate mathematical descriptions of the thermodynamic data of naproxen in the investigated binary solvent systems. PMID:26664370

  16. Synthesis of silver nanoparticles in melts of amphiphilic polyesters

    NASA Astrophysics Data System (ADS)

    Vasylyev, S.; Damm, C.; Segets, D.; Hanisch, M.; Taccardi, N.; Wasserscheid, P.; Peukert, W.

    2013-03-01

    The current work presents a one-step procedure for the synthesis of amphiphilic silver nanoparticles suitable for production of silver-filled polymeric materials. This solvent free synthesis via reduction of Tollens’ reagent as silver precursor in melts of amphiphilic polyesters consisting of hydrophilic poly(ethylene glycol) blocks and hydrophobic alkyl chains allows the production of silver nanoparticles without any by-product formation. This makes them especially interesting for the production of medical devices with antimicrobial properties. In this article the influences of the chain length of the hydrophobic block in the amphiphilic polyesters and the process temperature on the particle size distribution (PSD) and the stability of the particles against agglomeration are discussed. According to the results of spectroscopic and viscosimetric investigations the silver precursor is reduced to elemental silver nanoparticles by a single electron transfer process from the poly(ethylene glycol) chain to the silver ion.

  17. Optimization of PEG-based extraction of polysaccharides from Dendrobium nobile Lindl. and bioactivity study.

    PubMed

    Zhang, Yi; Wang, Hongxin; Wang, Peng; Ma, ChaoYang; He, GuoHua; Rahman, Md Ramim Tanver

    2016-11-01

    Polyethylene glycol (PEG) as a green solvent was employed to extract polysaccharide. The optimal conditions for PEG-based ultrasonic extraction of Dendrobium nobile Lindl. polysaccharide (JCP) were determined by response surface methodology. Under the optimal conditions: extraction temperature of 58.5°C; ultrasound power of 193W, and the concentration of polyethylene glycol-200 (PEG-200) solution of 45%, the highest JCP yield was obtained as 15.23±0.57%, which was close to the predicted yield, 15.57%. UV and FT-IR analysis revealed the general characteristic absorption peaks of both JCP with water extraction (JCP w ) and PEG-200 solvent extraction (JCP p ). Thermal analysis of both JCPs was performed with Thermal Gravimetric Analyzer (TGA) and Differential Scanning Calorimeter (DSC). Antioxidant activities of two polysaccharides were also compared and no significant difference in vitro was obtained. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Fabrication of anti-protein-fouling poly(ethylene glycol) microfluidic chip electrophoresis by sandwich photolithography

    PubMed Central

    Cong, Hailin; Xu, Xiaodan; Yu, Bing; Liu, Huwei

    2016-01-01

    Microfluidic chip electrophoresis (MCE) is a powerful separation tool for biomacromolecule analysis. However, adsorption of biomacromolecules, particularly proteins onto microfluidic channels severely degrades the separation performance of MCE. In this paper, an anti-protein-fouling MCE was fabricated using a novel sandwich photolithography of poly(ethylene glycol) (PEG) prepolymers. Photopatterned microchannel with a minimum resolution of 10 μm was achieved. After equipped with a conventional online electrochemical detector, the device enabled baseline separation of bovine serum albumin, lysozyme (Lys), and cytochrome c (Cyt-c) in 53 s under a voltage of 200 V. Compared with a traditional polydimethylsiloxane MCE made by soft lithography, the PEG MCE made by the sandwich photolithography not only eliminated the need of a master mold and the additional modification process of the microchannel but also showed excellent anti-protein-fouling properties for protein separation. PMID:27493702

  19. Molar mass fractionation in aqueous two-phase polymer solutions of dextran and poly(ethylene glycol).

    PubMed

    Zhao, Ziliang; Li, Qi; Ji, Xiangling; Dimova, Rumiana; Lipowsky, Reinhard; Liu, Yonggang

    2016-06-24

    Dextran and poly(ethylene glycol) (PEG) in phase separated aqueous two-phase systems (ATPSs) of these two polymers, with a broad molar mass distribution for dextran and a narrow molar mass distribution for PEG, were separated and quantified by gel permeation chromatography (GPC). Tie lines constructed by GPC method are in excellent agreement with those established by the previously reported approach based on density measurements of the phases. The fractionation of dextran during phase separation of ATPS leads to the redistribution of dextran of different chain lengths between the two phases. The degree of fractionation for dextran decays exponentially as a function of chain length. The average separation parameters, for both dextran and PEG, show a crossover from mean field behavior to Ising model behavior, as the critical point is approached. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Urticaria due to polyethylene glycol-3350 and electrolytes for oral solution in a patient with jejunal nodular lymphoid hyperplasia.

    PubMed

    Zhang, Hongfeng; Henry, Winoah A; Chen, Lea Ann; Khashab, Mouen A

    2015-01-01

    Both jejunal nodular lymphoid hyperplasia (NLH) and polyethylene glycol (PEG)-3350 hypersensitivity are extremely rare. We describe a 30-year-old female who had previously taken a PEG-3350 bowel preparation without adverse effects, and presented for evaluation of chronic diarrhea. An upper and lower gastrointestinal endoscopy, and small bowel series were scheduled. PEG-3350 and electrolytes for oral solution was prescribed for bowel cleansing. During consumption of the bowel preparation she developed urticarial hypersensitivity. An alternative bowel preparation was used. Colonoscopy and upper endoscopy were normal, but small bowel series revealed innumerable sand-like lucencies in the jejunum. NLH was confirmed on biopsy from antegrade enteroscopy. This is the first case report on the pathological jejunal NLH in association with the PEG-3350 urticarial hypersensitivity. The potential pathophysiological etiology of this association is discussed.

  1. Urticaria due to polyethylene glycol-3350 and electrolytes for oral solution in a patient with jejunal nodular lymphoid hyperplasia

    PubMed Central

    Zhang, Hongfeng; Henry, Winoah A.; Chen, Lea Ann; Khashab, Mouen A.

    2015-01-01

    Both jejunal nodular lymphoid hyperplasia (NLH) and polyethylene glycol (PEG)-3350 hypersensitivity are extremely rare. We describe a 30-year-old female who had previously taken a PEG-3350 bowel preparation without adverse effects, and presented for evaluation of chronic diarrhea. An upper and lower gastrointestinal endoscopy, and small bowel series were scheduled. PEG-3350 and electrolytes for oral solution was prescribed for bowel cleansing. During consumption of the bowel preparation she developed urticarial hypersensitivity. An alternative bowel preparation was used. Colonoscopy and upper endoscopy were normal, but small bowel series revealed innumerable sand-like lucencies in the jejunum. NLH was confirmed on biopsy from antegrade enteroscopy. This is the first case report on the pathological jejunal NLH in association with the PEG-3350 urticarial hypersensitivity. The potential pathophysiological etiology of this association is discussed. PMID:25608714

  2. Poly(ethylene glycol)s in Semidilute Regime: Radius of Gyration in the Bulk and Partitioning into a Nanopore

    DOE PAGES

    Gurnev, Philip A.; Stanley, Christopher B.; Aksoyoglu, M. Alphan; ...

    2017-03-09

    In this work, using two approaches, small-angle neutron scattering (SANS) from bulk solutions and nanopore conductance-fluctuation analysis, we studied structural and dynamic features of poly(ethylene glycol) (PEG) water/salt solutions in the dilute and semidilute regimes. SANS measurements on PEG 3400 at the zero-average contrast yielded the single chain radius of gyration (R g) over 1–30 wt %. We observed a small but statistically reliable decrease in R g with increasing PEG concentration: at 30 wt % the chain contracts by a factor of 0.94. Analyzing conductance fluctuations of the α-hemolysin nanopore in the mixtures of PEG 200 with PEG 3400,more » we demonstrated that polymer partitioning into the nanopore is mostly due to PEG 200. Specifically, for a 1:1 wt/wt mixture the smaller polymer dominates to the extent that only about 1/25 of the nanopore volume is taken by the larger polymer. In conclusion, these findings advance our conceptual and quantitative understanding of nanopore polymer partitioning; they also support the main assumptions of the recent “polymers-pushing-polymers” model.« less

  3. Synthesis and characterization of poly(L-alanine)-block-poly(ethylene glycol) monomethyl ether as amphiphilic biodegradable co-polymers.

    PubMed

    Zhang, Guolin; Ma, Jianbiao; Li, Yanhong; Wang, Yinong

    2003-01-01

    Di-block co-polymers of poly(L-alanine) with poly(ethylene glycol) monomethyl ether (MPEG) were synthesized as amphiphilic biodegradable co-polymers. The ring-opening polymerization of N-carboxy-L-alanine anhydride (NCA) in dichloromethane was initiated by amino-terminated poly(ethylene glycol) monomethyl ether (MPEG-NH2, M(n) = 2000) to afford poly(L-alanine)-block-MPEG. The weight ratio of two blocks in the co-polymers could be altered by adjusting the feeding ratio of NCA to MPEG-NH2. Their chemical structures were characterized on the basis of infrared spectrometry and nuclear magnetic resonance. According to circular dichroism measurement, the poly(L-alanine) chain on the co-polymers in an aqueous medium had a alpha-helix conformation. Two melting points from MPEG block and poly(L-alanine), respectively, could be observed in differential scanning calorimetry curves of the co-polymers, suggesting that a micro-domain phase separation appeared in their bulky states. The co-polymers could take up some water and the capacity was dependent on the ratio of poly(L-alanine) block to MPEG. Such co-polymers might be useful in drug-delivery systems and other biomedical applications.

  4. Difference of carboxybetaine and oligo(ethylene glycol) moieties in altering hydrophobic interactions: a molecular simulation study.

    PubMed

    Shao, Qing; White, Andrew D; Jiang, Shaoyi

    2014-01-09

    Polycarboxybetaine and poly(ethylene glycol) materials resist nonspecific protein adsorption but differ in influencing biological functions such as enzymatic activity. To investigate this difference, we studied the influence of carboxybetaine and oligo(ethylene glycol) moieties on hydrophobic interactions using molecular simulations. We employed a model system composed of two non-polar plates and studied the potential of mean force of plate-plate association in carboxybetaine, (ethylene glycol)4, and (ethylene glycol)2 solutions using well-tempered metadynamics simulations. Water, trimethylamine N-oxide, and urea solutions were used as reference systems. We analyzed the variation of the potential of mean force in various solutions to study how carboxybetaine and oligo(ethylene glycol) moieties influence the hydrophobic interactions. To study the origin of their influence, we analyzed the normalized distributions of moieties and water molecules using molecular dynamics simulations. The simulation results showed that oligo(ethylene glycol) moieties repel water molecules away from the non-polar plates and weaken the hydrophobic interactions. Carboxybetaine moieties do not repel water molecules away from the plates and therefore do not influence the hydrophobic interactions.

  5. Optimization Properties of Environmentally Friendly Paper Coating Based Starch-Polyethylene glycol (PEG) Mixture

    NASA Astrophysics Data System (ADS)

    Galih Saputri, Diani; Khairuddin; Dwi Nurhayati, Nanik; Pham, Trinh

    2017-11-01

    The use of starch as biodegradable base material for packaging application was of great interest as an environmentally friendly alternative to the present use of polyethylene and polyvinyl chloride. However, starch tended to be brittle and had a lack of stability due to exposure to water. Several aproaches have been done to improve shellac properties including through chemical modification, mixing with polymers, clays, and plasticizers. The present study related to optimization of starch properties when mixing with polyethylene glycol (PEG) coated on the paper. The aim was to obtain the temperature and mixing time between starch and PEG so produced composites with optimal barrier properties. The composites of PEG/starch 10 % w/w were prepared using solvent casting and coated on paper surface, and dried in the oven for 12 hours at 40°C. Water Vapour Transmitter Rate (WVTR) (Payne cup method) showed that 70°C was the optimum temperature when mixing time was 30 minutes. Moreover, it showed that the optimum mixing time was 30 minutes when mixing temperature was 80 and 70 °C. Fourier Transform Infra Red (FTIR) showed a strong interaction between PEG400 and starch.

  6. Controlled-Release Personal Use Arthropod Repellent Formulation. Phase 3

    DTIC Science & Technology

    1987-08-26

    Polyethylene Glycol (200) Glyceryl Monotallowate (Varonic L1420) 54.2 lbs. Glyceryl Stearate/ Sodium Lauryl Sulfate (Lexemul AS) 129.3 lbs. Propylene... Sulfate 6-0 Xr ________ (Le.ernul AS) - 0.65__ * 13W00 Cetyl Palmitate (W,xenol 816) 2,600 Xg. Ci Zq! 167 2.2___ 10026 Poyproplen Gycol (15) Stenryl...1 Stearate7Sodium lAu 1l Sulfate T- 4fIa- TW _ - ________ Lex emul AS)__________ ____ _______ 2.41 11315 /Prop lene Glycol D1 cap" lateDf~caerate

  7. DELIVERY OF THERAPEUTIC PROTEINS

    PubMed Central

    Pisal, Dipak S.; Kosloski, Matthew P.; Balu-Iyer, Sathy V.

    2009-01-01

    The safety and efficacy of protein therapeutics are limited by three interrelated pharmaceutical issues, in vitro and in vivo instability, immunogenicity and shorter half-lives. Novel drug modifications for overcoming these issues are under investigation and include covalent attachment of poly(ethylene glycol) (PEG), polysialic acid, or glycolic acid, as well as developing new formulations containing nanoparticulate or colloidal systems (e.g. liposomes, polymeric microspheres, polymeric nanoparticles). Such strategies have the potential to develop as next generation protein therapeutics. This review includes a general discussion on these delivery approaches. PMID:20049941

  8. Synthesis and characterization of CdSe/ZnS quantum dots conjugated with poly (ethylene glycol) diamine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bharti, Shivani; Tripathi, S. K., E-mail: surya@pu.ac.in; Kaur, Gurvir

    2015-08-28

    Bio-functionalization or surface modification is an important technique to obtain biocompatibility in semiconductor nanoparticles for biomedical applications. In this study semiconductor core/shell quantum dots of CdSe/ZnS have been prepared by chemical reduction method and then further PEGylated using Poly(ethylene glycol) diamine of M{sub w} 2000. They were characterized by UV-vis spectroscopy & Fourier transform infrared spectroscopy. The results reveals the successful PEGylation of CdSe/ZnS quantum dots.

  9. Colloidal Stability of Gold Nanoparticles Coated with Multithiol-Poly(ethylene glycol) Ligands: Importance of Structural Constraints of the Sulfur Anchoring Groups

    DTIC Science & Technology

    2013-08-13

    21-45 Citric acid has been the most commonly used ligand when negatively charged surfaces or a rather loose ligand shell is required for further...biomolecules in biological serum (e.g., proteins, peptides, nucleic acids ); (5) resistance to heat treatments (e.g., >80 °C for DNA hybridization).6-8, 16...demonstrated by a variety of thiol-based ligands such as mercaptopropionic acid ,36 glutathione,37 thiol-terminated poly(ethylene glycol) (PEG-SH), 19

  10. Poly(ethylene glycol)-Mediated Collagen Gel Mechanics Regulates Cellular Phenotypes in a Microchanneled Matrix.

    PubMed

    Rich, Max H; Lee, Min Kyung; Ballance, William C; Boppart, Marni; Kong, Hyunjoon

    2017-08-14

    For the past few decades, efforts have been extensively made to reproduce tissue of interests for various uses including fundamental bioscience studies, clinical treatments, and even soft robotic systems. In these studies, cells are often cultured in micropores introduced in a provisional matrix despite that bulk rigidity may negatively affect cellular differentiation involved in tissue formation. To this end, we hypothesized that suspending cells within a soft fibrous matrix that is encapsulated within the microchannels of a provisional matrix would allow us to mediate effects of the matrix rigidity on cells and, in turn, to increase the cell differentiation level. We examined this hypothesis by filling microchannels interpenetrating alginate matrices with collagen gels of controlled elastic moduli (i.e., 125 to 1 Pa). Myoblasts used as a model predifferentiated cell were suspended within the collagen gels. The elastic modulus of the collagen gels was decreased through the addition of poly(ethylene glycol) during the gel preparation. Myoblasts loaded in the collagen gel exhibited a higher myogenic differentiation level than those adhered to the collagen-coated microchannel wall. Furthermore, the collagen gel softened by poly(ethylene glycol) further increased the volume of the multinucleated myofibers. The role of collagen gel softness on cell differentiation became more significant when the bulk elastic modulus of the alginate matrix was tuned to be close to that of muscle tissue (i.e., 11 kPa). We believe that the results of this study would be useful to understanding phenotypic activities of a wide array of cells involved in tissue development and regeneration.

  11. A polymeric prodrug of 5-fluorouracil-1-acetic acid using a multi-hydroxyl polyethylene glycol derivative as the drug carrier.

    PubMed

    Li, Man; Liang, Zhen; Sun, Xun; Gong, Tao; Zhang, Zhirong

    2014-01-01

    Macromolecular prodrugs obtained by covalently conjugating small molecular drugs with polymeric carriers were proven to accomplish controlled and sustained release of the therapeutic agents in vitro and in vivo. Polyethylene glycol (PEG) has been extensively used due to its low toxicity, low immunogenicity and high biocompatibility. However, for linear PEG macromolecules, the number of available hydroxyl groups for drug coupling does not change with the length of polymeric chain, which limits the application of PEG for drug conjugation purposes. To increase the drug loading and prolong the retention time of 5-fluorouracil (5-Fu), a macromolecular prodrug of 5-Fu, 5-fluorouracil-1 acid-PAE derivative (5-FA-PAE) was synthesized and tested for the antitumor activity in vivo. PEG with a molecular weight of 38 kDa was selected to synthesize the multi-hydroxyl polyethylene glycol derivative (PAE) through an addition reaction. 5-fluorouracil-1 acetic acid (5-FA), a 5-Fu derivative was coupled with PEG derivatives via ester bond to form a macromolecular prodrug, 5-FA-PAE. The in vitro drug release, pharmacokinetics, in vivo distribution and antitumor effect of the prodrug were investigated, respectively. The PEG-based prodrug obtained in this study possessed an exceedingly high 5-FA loading efficiency of 10.58%, much higher than the maximum drug loading efficiency of unmodified PEG with the same molecular weight, which was 0.98% theoretically. Furthermore, 5-FA-PAE exhibited suitable sustained release in tumors. This study provides a new approach for the development of the delivery to tumors of anticancer agents with PEG derivatives.

  12. Hepatocyte-targeting gene transfer mediated by galactosylated poly(ethylene glycol)-graft-polyethylenimine derivative

    PubMed Central

    Wang, Yuqiang; Su, Jing; Cai, Wenwei; Lu, Ping; Yuan, Lifen; Jin, Tuo; Chen, Shuyan; Sheng, Jing

    2013-01-01

    Biscarbamate cross-linked polyethylenimine derivative (PEI-Et) has been reported as a novel nonviral vector for efficient and safe gene transfer in our previous work. However, it had no cell-specificity. To achieve specific delivery of genes to hepatocytes, galactosylated poly(ethylene glycol)-graft-polyethylenimine derivative (GPE) was prepared through modification of PEI-Et with poly(ethylene glycol) and lactobionic acid, bearing a galactose group as a hepatocyte-targeting moiety. The composition of GPE was characterized by proton nuclear magnetic resonance. The weight-average molecular weight of GPE measured with a gel permeation chromatography instrument was 9489 Da, with a polydispersity of 1.44. GPE could effectively condense plasmid DNA (pDNA) into nanoparticles. Gel retardation assay showed that GPE/pDNA complexes were completely formed at weigh ratios (w/w) over 3. The particle size of GPE/pDNA complexes was 79–100 nm and zeta potential was 6–15 mV, values which were appropriate for cellular uptake. The morphology of GPE/pDNA complexes under atomic force microscopy appeared spherical and uniform in size, with diameters of 53–65 nm. GPE displayed much higher transfection efficiency than commercially available PEI 25 kDa in BRL-3A cell lines. Importantly, GPE showed good hepatocyte specificity. Also, the polymer exhibited significantly lower cytotoxicity compared to PEI 25 kDa at the same concentration or weight ratio in BRL-3A cell lines. To sum up, our results indicated that GPE might carry great potential in safe and efficient hepatocyte-targeting gene delivery. PMID:23576866

  13. 2-Litre polyethylene glycol-citrate-simethicone plus bisacodyl versus 4-litre polyethylene glycol as preparation for colonoscopy in chronic constipation.

    PubMed

    Parente, Fabrizio; Vailati, Cristian; Bargiggia, Stefano; Manes, Gianpiero; Fontana, Paola; Masci, Enzo; Arena, Monica; Spinzi, Giancarlo; Baccarin, Alessandra; Mazzoleni, Giorgia; Testoni, Pier Alberto

    2015-10-01

    Chronic constipation is a risk factor of inadequate bowel preparation for colonoscopy; however, no large clinical trials have been performed in this subgroup of patients. To compare bowel cleansing efficacy, tolerability and acceptability of 2-L polyethylene-glycol-citrate-simethicone (PEG-CS) plus 2-day bisacodyl (reinforced regimen) vs. 4-L PEG in patients with chronic constipation undergoing colonoscopy. Randomized, observer-blind, parallel group study. Adult outpatients undergoing colonoscopy were randomly allocated to 2-L PEG-CS/bisacodyl or 4-L PEG, taken as split regimens before colonoscopy. Quality of bowel preparation was assessed by the Ottawa Bowel Cleansing Scale (OBCS). The amount of foam/bubble interfering with colonic visualization was also measured. 400 patients were enrolled. There was no significant difference in successful cleansing (OBCS score ≤6): 80.2% in the 2-L PEG-CS/bisacodyl vs. 81.4% in the 4-L PEG group. Significantly more patients taking 2L PEG-CS/bisacodyl showed no or minimal foam/bubbles in all colonic segments (80% vs. 63%; p<0.001). 2-L PEG-CS/bisacodyl was significantly more acceptable for ease of administration (p<0.001), willingness to repeat (p<0.001) and showed better compliance (p=0.002). Split 2-L PEG-CS plus bisacodyl was not superior to split 4-L PEG for colonoscopy bowel cleansing in patients with chronic constipation; however, it performed better than the standard regimen in terms of colonic mucosa visualization, patient acceptance and compliance. Copyright © 2015 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  14. Vorinostat with sustained exposure and high solubility in poly(ethylene glycol)-b-poly(DL-lactic acid) micelle nanocarriers: characterization and effects on pharmacokinetics in rat serum and urine.

    PubMed

    Mohamed, Elham A; Zhao, Yunqi; Meshali, Mahasen M; Remsberg, Connie M; Borg, Thanaa M; Foda, Abdel Monem M; Takemoto, Jody K; Sayre, Casey L; Martinez, Stephanie E; Davies, Neal M; Forrest, M Laird

    2012-10-01

    The histone deacetylase inhibitor suberoylanilide hydroxamic acid, known as vorinostat, is a promising anticancer drug with a unique mode of action; however, it is plagued by low water solubility, low permeability, and suboptimal pharmacokinetics. In this study, poly(ethylene glycol)-b-poly(DL-lactic acid) (PEG-b-PLA) micelles of vorinostat were developed. Vorinostat's pharmacokinetics in rats was investigated after intravenous (i.v.) (10 mg/kg) and oral (p.o.) (50 mg/kg) micellar administrations and compared with a conventional polyethylene glycol 400 solution and methylcellulose suspension. The micelles increased the aqueous solubility of vorinostat from 0.2 to 8.15 ± 0.60 and 10.24 ± 0.92 mg/mL at drug to nanocarrier ratios of 1:10 and 1:15, respectively. Micelles had nanoscopic mean diameters of 75.67 ± 7.57 and 87.33 ± 8.62 nm for 1:10 and 1:15 micelles, respectively, with drug loading capacities of 9.93 ± 0.21% and 6.91 ± 1.19%, and encapsulation efficiencies of 42.74 ± 1.67% and 73.29 ± 4.78%, respectively. The micelles provided sustained exposure and improved pharmacokinetics characterized by a significant increase in serum half-life, area under curve, and mean residence time. The micelles reduced vorinostat clearance particularly after i.v. dosing. Thus, PEG-b-PLA micelles significantly improved the p.o. and i.v. pharmacokinetics and bioavailability of vorinostat, which warrants further investigation. Copyright © 2012 Wiley Periodicals, Inc.

  15. Spectroscopic characterization of PET glycolysis and surface molecular orientation of polymers

    NASA Astrophysics Data System (ADS)

    Weir, Michael David

    This dissertation seeks to develop novel polymer characterization techniques using UV and fluorescence spectroscopy. The first portion of the dissertation consists of monitoring the glycolytic depolymerization of poly(ethylene terephthalate), PET, using UV and fluorescence spectroscopy. The primary product of the glycolysis of PET is bis(hydroxyethyl) tereplithalate (BHET), along with other low molecular weight oligomers (degree of polymerization = 1--3). The UV absorption of the glycolized products occurs at 287 nm and is associated with the pi → pi* transition of the tereplithalate moiety. This absorption band shows a linear increase with reaction time that corresponds to an increase in the concentration of glycolized products. BHET was selected as a model compound to represent the glycolized products and was used to calculate the concentration of glycolized products. When using excitation wavelengths of 300 nm and 340 nm, fluorescence emission spectra of the glycolized products were observed at 350 nm and 380 nm respectively. These emission bands also showed an increase in intensity corresponding to the concentration increase. Again, BHET was used as a model compound to simulate and calculate the concentration of the glycolized products. We determined the overall reaction to be second order and that the reaction rate is strongly dependent on the glycol concentration; an increase in the glycol concentration results in an increase in the reaction rate. The second portion of this dissertation consists of the characterization of surface molecular orientation of poly(ethylene terephthalate) (PET) and Kaptono films by UV reflection dichroism using a specular reflection accessory and a bifurcated fiber optic. The UV reflection peaks for PET and Kapton RTM occur at 257 nm and 310 nm respectively. The orientation function and dichroic ratio calculated using both specular reflection and the fiber optic agreed well with each other. Additionally, correct placement of the polarizer is essential in producing good results. When placed at either the source or detector side of the fiber, there was no evidence of orientation seen. However, placement at the common end shows good agreement with the results from the specular reflection accessory. These different results are a manifestation of the polarization/depolarization characteristics of the fiber optic.

  16. Accurate quantification of hydration number for polyethylene glycol molecules

    NASA Astrophysics Data System (ADS)

    Guo, Wei; Zhao, Lishan; Gao, Xin; Cao, Zexian; Wang, Qiang

    2018-05-01

    Not Available Project supported by the National Natural Science Foundation of China (Grant Nos. 11474325 and 11290161) and the Knowledge Innovation Project of Chinese Academy of Sciences on Water Science Research (Grant No. KJZD-EW-M03).

  17. Injectible bodily prosthetics employing methacrylic copolymer gels

    DOEpatents

    Mallapragada, Surya K.; Anderson, Brian C.

    2007-02-27

    The present invention provides novel block copolymers as structural supplements for injectible bodily prosthetics employed in medical or cosmetic procedures. The invention also includes the use of such block copolymers as nucleus pulposus replacement materials for the treatment of degenerative disc disorders and spinal injuries. The copolymers are constructed by polymerization of a tertiary amine methacrylate with either a (poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) polymer, such as the commercially available Pluronic.RTM. polymers, or a poly(ethylene glycol) methyl ether polymer.

  18. pH-sensitive methacrylic copolymer gels and the production thereof

    DOEpatents

    Mallapragada, Surya K [Ames, IA; Anderson, Brian C [Lake Bluff, IA

    2007-05-15

    The present invention provides novel gel forming methacrylic blocking copolymers that exhibit cationic pH-sensitive behavior as well as good water solubility. The copolymers are constructed by polymerization of a tertiary amine methacrylate with either a (poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) polymer, such as the commercially available Pluronic.RTM. polymers, or a poly(ethylene glycol)methyl ether polymer. The polymers may be used for drug and gene delivery, protein separation, as structural supplements, and more.

  19. Engineering biofunctional magnetic nanoparticles for biotechnological applications

    NASA Astrophysics Data System (ADS)

    Moros, Maria; Pelaz, Beatriz; López-Larrubia, Pilar; García-Martin, Maria L.; Grazú, Valeria; de La Fuente, Jesus M.

    2010-09-01

    Synthesis and characterization of magnetic nanoparticles with excellent size control are showed here. Their functionalization using an amphiphilic polymer is also described. This strategy allows the stabilization of magnetic nanoparticles in aqueous solvents and in addition, the polymer shell serves as a platform to incorporate relevant biomolecules, such as poly(ethylene glycol) and a number of carbohydrates. Nanoparticles functionalized with carbohydrates show the ability to avoid unspecific interactions between proteins present in the working medium and the nanoparticles, so can be used as an alternative to poly(ethylene glycol) molecules. Results confirm these nanoparticles as excellent contrast agents for magnetic resonance imaging. Changes in the spin-spin transversal relaxation times of the surrounding water protons due to nanoparticle aggregation demonstrates the bioactivity of these nanoparticles functionalized with carbohydrates. To finish with, nanoparticle toxicity is evaluated by means of MTT assay. The obtained results clearly indicate that these nanoparticles are excellent candidates for their further application in nanomedicine or nanobiotechnology.Synthesis and characterization of magnetic nanoparticles with excellent size control are showed here. Their functionalization using an amphiphilic polymer is also described. This strategy allows the stabilization of magnetic nanoparticles in aqueous solvents and in addition, the polymer shell serves as a platform to incorporate relevant biomolecules, such as poly(ethylene glycol) and a number of carbohydrates. Nanoparticles functionalized with carbohydrates show the ability to avoid unspecific interactions between proteins present in the working medium and the nanoparticles, so can be used as an alternative to poly(ethylene glycol) molecules. Results confirm these nanoparticles as excellent contrast agents for magnetic resonance imaging. Changes in the spin-spin transversal relaxation times of the surrounding water protons due to nanoparticle aggregation demonstrates the bioactivity of these nanoparticles functionalized with carbohydrates. To finish with, nanoparticle toxicity is evaluated by means of MTT assay. The obtained results clearly indicate that these nanoparticles are excellent candidates for their further application in nanomedicine or nanobiotechnology. Electronic supplementary information (ESI) available: Chemical, physical and magnetic characterization; R2 maps; stability of NPs at different conditions; size of glucose NPs in the presence of Concanavalin A; MTT assays of the samples are shown in figures S1-S10. Table S1 represents the hydrodynamic size of PMAO NPs after being washed with different solvents. See DOI: 10.1039/c0nr00104j

  20. Enzyme-catalyzed modifications of polysaccharides and poly(ethylene glycol)

    USDA-ARS?s Scientific Manuscript database

    Polysaccharides are used extensively in various industrial applications, such as food, adhesives, coatings, construction, paper, pharmaceuticals, and personal care. Many polysaccharide structures need to be modified in order to improve their end-use properties; these are mostly done through chemica...

  1. DECONTAMINATION OF STRUCTURES AND DEBRIS AT SUPERFUND SITES

    EPA Science Inventory

    Two building decontamination technologies were demonstrated and evaluated: a method for in situ degradation of PCB's requiring application of an alkali metal/polyethylene glycolate mixture directly on concrete surfaces; and a shotblasting technique using steel shot to cut away co...

  2. Liposomes as potential masking agents in sport doping. Part 2: Detection of liposome-entrapped haemoglobin by flow cytofluorimetry.

    PubMed

    Esposito, Simone; Colicchia, Sonia; de la Torre, Xavier; Donati, Francesco; Mazzarino, Monica; Botrè, Francesco

    2017-02-01

    This work presents an analytical procedure for the identification and characterization of liposome-entrapped haemoglobins, based on flow cytofluorimetry. Flow cytofluorimetric detection is carried out following labelling by two distinct fluorescent reagents, an anti-haemoglobin antibody, fluorescein isothiocyanate conjugated, and an anti-poly(ethylene glycol) antibody, streptavidin-phycoerythrin conjugated. This experimental strategy allows the detection of liposome-entrapped haemoglobins in aqueous media, including plasma; the efficacy of the proposed approach has been verified on whole blood samples added with the liposomal formulation (ex-vivo). Additionally, the proposed technique allows the characterization of several key parameters in the study of liposomal haemoglobins, including, for instance (1) the determination of the degree of haemoglobin entrapment by liposomes; (2) the poly(ethylene glycol) insertion efficiency; and (3) the evaluation of liposome-entrapped haemoglobins stability following storage at 4 °C, allowing to follow both the process of haemoglobin loss from liposomes and the liposome degradation. The procedure is proposed for the detection and characterization of liposome-entrapped haemoglobin formulations to control their misuse in sport, but is also suggested for further applications in biological and clinical laboratory investigations. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  3. Wood Technology: Techniques, Processes, and Products

    ERIC Educational Resources Information Center

    Oatman, Olan

    1975-01-01

    Seven areas of wood technology illustrates applicable techniques, processes, and products for an industrial arts woodworking curriculum. They are: wood lamination; PEG (polyethylene glycol) diffusion processes; wood flour and/or particle molding; production product of industry; WPC (wood-plastic-composition) process; residential construction; and…

  4. Transformation of Streptococcus lactis Protoplasts by Plasmid DNA †

    PubMed Central

    Kondo, Jeffery K.; McKay, Larry L.

    1982-01-01

    Polyethylene glycol-treated protoplasts prepared from Streptococcus lactis LM3302, a lactose-negative (Lac−) derivative of S. lactis ML3, were transformed to lactose-fermenting ability by a transductionally shortened plasmid (pLM2103) coding for lactose utilization. Images PMID:16346019

  5. Effect of Co-Solutes on Template-Directed Nonenzymatic Copying of RNA

    NASA Astrophysics Data System (ADS)

    Bapat, N. V.; Rajamani, S.

    2017-07-01

    Given the heterogeneous nature of the prebiotic milieu, we report here, the effect of presence of lipid vesicles and Polyethylene Glycol (PEG) as co-solutes on the rate and accuracy of enzyme-free template-directed RNA primer extension reactions.

  6. Effect of Branched Gap Synthesis Parameters on Mechanical Properties of Rocket Propellants

    DTIC Science & Technology

    1995-12-01

    modulus hydroxyl functionality glycidyl azide polymer hexanetriol hydroxy-terminated polybutadiene isophorone diisocyanate hydroxyl equivalent... hexanetriol (HT), glycerol and polyethylene glycol (PEG) with MW 600. The reaction was carried out with one polyol or a blend of two polyols and

  7. PEG-nanotube liquid crystals as templates for construction of surfactant-free gold nanorods.

    PubMed

    Kameta, Naohiro; Shiroishi, Hidenobu

    2018-05-03

    Lyotropic liquid crystals, in which nanotubes coated with polyethylene glycol were aligned side-by-side in aqueous dispersions, acted as templates for the construction of surfactant-free gold nanorods with controllable diameters, functionalizable surfaces, and tunable optical properties.

  8. Molecular simulation of fibronectin adsorption onto polyurethane surfaces

    USDA-ARS?s Scientific Manuscript database

    Polyethylene glycol-based polyurethanes have been widely used in biomedical applications, however are prone to swelling. A natural polyol, castor oil can be incorporated into these polyurethanes to control the degree of the swelling, which alters mechanical properties and protein adsorption characte...

  9. 21 CFR 73.2180 - Guaiazulene.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2180 Guaiazulene. (a) Identity. (1) The color additive... cosmetic use may contain the following diluent: Polyethylene glycol-40 castor oil (PEG-40 castor oil... applied cosmetics in amounts consistent with good manufacturing practice. (d) Labeling. The label of the...

  10. 21 CFR 73.2180 - Guaiazulene.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2180 Guaiazulene. (a) Identity. (1) The color additive... cosmetic use may contain the following diluent: Polyethylene glycol-40 castor oil (PEG-40 castor oil... applied cosmetics in amounts consistent with good manufacturing practice. (d) Labeling. The label of the...

  11. 21 CFR 73.2180 - Guaiazulene.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2180 Guaiazulene. (a) Identity. (1) The color additive... cosmetic use may contain the following diluent: Polyethylene glycol-40 castor oil (PEG-40 castor oil... applied cosmetics in amounts consistent with good manufacturing practice. (d) Labeling. The label of the...

  12. 21 CFR 73.2180 - Guaiazulene.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2180 Guaiazulene. (a) Identity. (1) The color additive... cosmetic use may contain the following diluent: Polyethylene glycol-40 castor oil (PEG-40 castor oil... applied cosmetics in amounts consistent with good manufacturing practice. (d) Labeling. The label of the...

  13. Chemical composition and the nutritive value of pistachio epicarp (in situ degradation and in vitro gas production techniques).

    PubMed

    Bakhshizadeh, Somayeh; Taghizadeh, Akbar; Janmohammadi, Hossein; Alijani, Sadegh

    2014-01-01

    The nutritive value of pistachio epicarp (PE) was evaluated by in situ and in vitro techniques. Chemical analysis indicated that PE was high in crude protein (11.30%) and low in neutral detergent fiber (26.20%). Total phenols, total tannins, condensed tannins and hydrolysable tannins contents in PE were 8.29%, 4.48%, 0.49% and 3.79%, respectively. Ruminal dry matter and crude protein degradation after 48 hr incubation were 75.21% and 82.52%, respectively. The gas production volume at 48 hr for PE was 122.47 mL g(-1)DM. As a whole, adding polyethylene glycol (PEG) to PE increased (p < 0.05) gas production volumes, organic matter digestibility and the metabolizable energy that illustrated inhibitory effect of phenolics on rumen microbial fermentation and the positive influence of PEG on digestion PE. The results showed that PE possessed potentials to being used as feed supplements.

  14. High throughput microencapsulation of Bacillus subtilis in semi-permeable biodegradable polymersomes for selenium remediation.

    PubMed

    Barlow, Jacob; Gozzi, Kevin; Kelley, Chase P; Geilich, Benjamin M; Webster, Thomas J; Chai, Yunrong; Sridhar, Srinivas; van de Ven, Anne L

    2017-01-01

    Encapsulating bacteria within constrained microenvironments can promote the manifestation of specialized behaviors. Using double-emulsion droplet-generating microfluidic synthesis, live Bacillus subtilis bacteria were encapsulated in a semi-permeable membrane composed of poly(ethylene glycol)-b-poly(D,L-lactic acid) (mPEG-PDLLA). This polymer membrane was sufficiently permeable to permit exponential bacterial growth, metabolite-induced gene expression, and rapid biofilm growth. The biodegradable microparticles retained structural integrity for several days and could be successfully degraded with time or sustained bacterial activity. Microencapsulated B. subtilis successfully captured and contained sodium selenite added outside the polymersomes, converting the selenite into elemental selenium nanoparticles that were selectively retained inside the polymer membrane. This remediation of selenium using polymersomes has high potential for reducing the toxicity of environmental selenium contamination, as well as allowing selenium to be harvested from areas not amenable to conventional waste or water treatment.

  15. pH-sensitive oncolytic adenovirus hybrid targeting acidic tumor microenvironment and angiogenesis

    PubMed Central

    Choi, Joung-Woo; Jung, Soo-Jung; Kasala, Dayananda; Hwang, June Kyu; Hu, Jun; Bae, You Han; Yun, Chae-Ok

    2015-01-01

    Although oncolytic adenoviruses (Ads) are an attractive option for cancer gene therapy, the intravenous administration of naked Ad still encounters unfavorable host responses, non-specific interactions, and heterogeneity in targeted cancer cells. To overcome these obstacles and achieve specific targeting of the tumor microenvironment, Ad was coated with the pH-sensitive block copolymer, methoxy poly(ethylene glycol)-b-poly(l-histidine-co-l-phenylalanine) (PEGbPHF). The physicochemical properties of the generated nanocomplex, Ad/PEGbPHF, were assessed. At pH 6.4, GFP-expressing Ad/PEGbPHF induced significantly higher GFP expression than naked Ad in both coxsackie and adenovirus receptor (CAR)-positive and -negative cells. To assess the therapeutic efficacy of the Ad/PEGbPHF complex platform, an oncolytic Ad expressing VEGF promoter-targeting transcriptional repressor (KOX) was used to form complexes. At pH 6.4, KOX/PEGbPHF significantly suppressed VEGF gene expression, cancer cell migration, vessel sprouting, and cancer cell killing effect compared to naked KOX or KOX/PEGbPHF at pH 7.4, demonstrating that KOX/PEGbPHF can overcome the lack of CAR that is frequently observed in tumor tissues. The antitumor activity of KOX/PEGbPHF systemically administered to a tumor xenograft model was significantly higher than that of naked KOX. Furthermore, KOX/PEGbPHF showed lower hepatic toxicity and did not induce an innate immune response against Ad. Altogether, these results demonstrate that pH-sensitive polymer-coated Ad complex significantly increases net positive charge upon exposure to hypoxic tumor microenvironment, allowing passive targeting to the tumor tissue. It may offer superior potential for systemic therapy, due to its improved tumor selectivity, increased therapeutic efficacy, and lower toxicity compared to naked KOX. PMID:25575865

  16. Experimental Study on the Efficacy of Site-Specific PEGylated Human Serum Albumins in Resuscitation From Hemorrhagic Shock.

    PubMed

    Song, Xinlei; Zhang, Shu; Cheng, Yanna; Zhao, Ting; Lian, Qianqian; Lu, Lu; Wang, Fengshan

    2016-11-01

    To evaluate the resuscitative efficacy and the effect on reperfusion injury of two site-specific PEGylated human serum albumins modified with linear or branched PEG20kDa, compared with saline, 8% human serum albumin and 25% human serum albumin, in a hemorrhagic shock model. Laboratory. Male Wistar rats. Prospective study. Rats were bled to hemorrhagic hypovolemic shock and resuscitated with different resuscitation fluids. The mean arterial pressure and blood gas variables were measured. Hemorheology analysis was performed to evaluate the influence of resuscitation on RBCs and blood viscosity. The microvascular state was indirectly characterized in terms of monocyte chemotactic protein-1 and endothelial nitric oxide synthase that related to shear stress and vasodilation, respectively. The levels of inflammation-related factors and apoptosis-related proteins were used to evaluate the reperfusion injury in lungs. The results showed that PEGylated human serum albumin could improve the level of mean arterial pressure and blood gas variables more effectively at the end of resuscitation. poly(ethylene glycol) modification was able to increase the viscosity of human serum albumin to the level of effectively enhancing the expression of monocyte chemotactic protein-1 and endothelial nitric oxide synthase, which could promote microvascular perfusion. The hyperosmotic resuscitative agents including both 25% human serum albumin and PEGylated human serum albumins could greatly attenuate lung injury. No significant therapeutic advantages but some disadvantages were found for Y shaped poly(ethylene glycol) modification over linear poly(ethylene glycol) modification, such as causing the decrease of erythrocyte deformability. Linear high molecular weight site-specific PEGylated human serum albumin is recommended to be used as a hyperosmotic resuscitative agent.

  17. Simultaneous small-angle neutron scattering and Fourier transform infrared spectroscopic measurements on cocrystals of syndiotactic polystyrene with polyethylene glycol dimethyl ethers.

    PubMed

    Kaneko, Fumitoshi; Seto, Naoki; Sato, Shuma; Radulescu, Aurel; Schiavone, Maria Maddalena; Allgaier, Jürgen; Ute, Koichi

    2016-10-01

    Syndiotactic polystyrene (sPS) is a crystalline polymer which has a unique property; it is able to form cocrystals with a wide range of chemical compounds, in which the guest molecules are confined in the vacancies of the host sPS crystalline region. Recently, it has been found that even polyethylene glycol oligomers with a molecular weight of more than several hundreds can be introduced into the sPS crystalline region. It is quite important to know how such a long-chain molecule is stored in the host sPS lattice. To tackle this issue, a new simultaneous measurement method combing small-angle neutron scattering and Fourier transform infrared spectroscopy (SANS/FTIR), which has been recently developed by the authors, was applied to an sPS cocrystal with polyethylene glycol dimethyl ether with a molecular weight of 500 (PEGDME500). The temperature-dependent changes of the SANS profile and FTIR spectrum were followed from room temperature up to 413 K for a one-dimensionally oriented SANS/PEGDME500 cocrystal sample. The intensity of the reflections due to the stacking of crystalline lamellae showed a significant temperature dependence. The two-dimensional pattern in the high Q region of SANS also changed depending on temperature. The combined information obtained by SANS and FTIR suggested that PEGDME500 molecules are distributed in both the crystalline and amorphous regions in the low-temperature region close to room temperature, but they are predominantly included in the amorphous region in the high-temperature region. It was also suggested by the two-dimensional SANS profile that PEGDME500 molecules in the crystalline region have an elongated structure along the thickness direction of the crystalline lamellae.

  18. Role of lipid phase separations and membrane hydration in phospholipid vesicle fusion.

    PubMed

    Hoekstra, D

    1982-06-08

    The relationship between lipid phase separation and fusion of small unilamellar phosphatidylserine-containing vesicles was investigated. The kinetics of phase separation were monitored by following the increase of self-quenching of the fluorescent phospholipid analogue N-(7-nitro-2,1,3-benzoxadiazol-4-yl)phosphatidylethanolamine, which occurs when the local concentration of the probe increases upon Ca2+-induced phase separation in phosphatidylserine (PS) bilayers [Hoekstra, D. (1982) Biochemistry 21, 1055-1061]. Fusion was determined by using the resonance energy transfer fusion assay [Struck, D. K., Hoekstra, D., & Pagano, R. E. (1981) Biochemistry 20, 4093-4099], which monitors the mixing of fluorescent lipid donor and acceptor molecules, resulting in an increase in energy transfer efficiency. The results show that in the presence of Ca2+, fusion proceeds much more rapidly (t 1/2 less than 5 s) than the process of phase separation (T 1/2 congruent to 1 min). Mg2+ also induced fusion, albeit at higher concentrations than Ca2+. Mg2+-induced phase separation were not detected, however. Subthreshold concentrations of Ca2+ (0.5 mM) or Mg2+ (2 mM) induced extensive fusion of PS-containing vesicles in poly(ethylene glycol) containing media. This effect did not appear to be a poly(ethylene glycol)-facilitated enhancement of cation binding to the bilayer, and consequently Ca2+-induced phase separation was not observed. The results suggest that macroscopic phase separation may facilitate but does not induced the fusion process and is therefore, not directly involved in the actual fusion mechanism. The fusion experiments performed in the presence of poly(ethylene glycol) suggest that the degree of bilayer dehydration and the creation of "point defects" in the bilayer without rigorous structural rearrangements in the membrane are dominant factors in the initial fusion events.

  19. Covalently immobilized platelet-derived growth factor-BB promotes angiogenesis in biomimetic poly(ethylene glycol) hydrogels

    PubMed Central

    Saik, Jennifer E.; Gould, Daniel J.; Watkins, Emily M.; Dickinson, Mary E.; West, Jennifer L.

    2011-01-01

    The field of tissue engineering is severely limited by a lack of microvascularization in tissue engineered constructs. Biomimetic poly(ethylene glycol) hydrogels containing covalently immobilized platelet-derived growth factor BB (PDGF-BB) were developed to promote angiogenesis. Poly(ethylene glycol) hydrogels resist protein absorption and subsequent non-specific cell adhesion, thus providing a “blank slate”, which can be modified through the incorporation of cell adhesive ligands and growth factors. PDGF-BB is a key angiogenic protein able to support neovessel stabilization by inducing functional anastomoses and recruiting pericytes. Due to the widespread effects of PDGF in the body and a half-life of only 30 min in circulating blood, immobilization of PDGF-BB may be necessary. In this work bioactive, covalently immobilized PDGF-BB was shown to induce tubulogenesis on two-dimensional modified surfaces, migration in three-dimensional (3D) degradable hydrogels and angiogenesis in a mouse cornea micro-pocket angiogenesis assay. Covalently immobilized PDGF-BB was also used in combination with covalently immobilized fibroblast growth factor-2, which led to significantly increased endothelial cell migration in 3D degradable hydrogels compared with the presentation of each factor alone. When a co-culture of endothelial cells and mouse pericyte precursor 10T1/2 cells was seeded onto modified surfaces tubule formation was independent of surface modifications with covalently immobilized growth factors. Furthermore, the combination of soluble PDGF-BB and immobilized PDGF-BB induced a more robust vascular response compared with soluble PDGF-BB alone when implanted into an in vivo mouse cornea micropocket angiogenesis assay. Based on these results, we believe bioactive hydrogels can be tailored to improve the formation of functional microvasculature for tissue engineering. PMID:20801242

  20. Crystalline polyoxometalate (POM)–polyethylene glycol (PEG) composites aimed as non-humidified intermediate-temperature proton conductors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsuboi, Masaki; Hibino, Mitsuhiro; Mizuno, Noritaka

    2016-02-15

    Crystalline polyoxometalate (POM)–polyethylene glycol (PEG) composites aimed as non-humidified intermediate-temperature proton conductors were synthesized and characterized by single crystal and powder XRD, solid state MASNMR, and TG-DTA measurements. Among the POM–PEG composites, Cs{sub 2.7}H{sub 0.3}[PW{sub 12}O{sub 40}]·1.2PEG1000 (CsHPW-PEG1000) possessed one-dimensional channels with diameters of ca. 6 and 8 Å, where PEG probably resided, and showed the best performance as a proton conductor (1.2×10{sup −5} S cm{sup −1} at 443 K). Proton conductivities of POM–PEG composites decreased by the increase in molecular weights of PEG (CsHPW-PEG12,000) or anion charges (CsHSiW-PEG1000). Variable contact time {sup 13}C-CP (cross polarization) MASNMR revealed that localmore » mobility (i.e., segmental motion) of PEG is related to the trends in proton conductivities. These results show that amount of acidic protons (H{sup +}) is not the primary factor in proton conduction and that segmental motion of PEG assists the proton hopping among POMs in the crystal lattice of POM–PEG composites. - Graphical abstract: Non-humidified intermediate-temperature proton conduction in crystalline polyoxometalate (POM)–polyethylene (PEG) composites are assisted by the segmental motion of PEG. - Highlights: • Crystalline polyoxometalate–polyethlene glycol (PEG) composites were synthesized. • CsHPW-PEG1000 possessed one-dimensional channels and showed the highest proton conductivity. • {sup 13}C CPMASNMR revealed that segmental motion of PEG is related to the proton conduction.« less

  1. Effectiveness of senna vs polyethylene glycol as laxative therapy in children with constipation related to anorectal malformation.

    PubMed

    Santos-Jasso, Karla Alejandra; Arredondo-García, José Luis; Maza-Vallejos, Jorge; Lezama-Del Valle, Pablo

    2017-01-01

    Constipation is present in 80% of children with corrected anorectal malformations, usually associated to rectal dilation and hypomotility. Osmotic laxatives are routinely used for idiopathic constipation. Senna is a stimulant laxative that produces contractions improving colonic motility without affecting the stool consistency. We designed this trial to study the effectiveness of Senna versus polyethylene glycol for the treatment of constipation in children with anorectal malformation. A randomized controlled crossover design clinical trial, including a washout period, was conducted, including children with corrected anorectal malformations with fecal continence and constipation. The sample size was calculated for proportions (n=28) according to available data for Senna. Effectiveness of laxative therapy was measured with a three variable construct: 1) daily bowel movement, 2) fecal soiling, 3) a "clean" abdominal x-ray. Data analysis included descriptive statistics and a Fisher's exact test for the outcome variable (effectiveness). The study was terminated early because the interim analysis showed a clear benefit toward Senna (p = 0.026). The sample showed a normal statistical distribution for the variables age and presence of megarectum. The maximum daily dose of Senna (sennosides A and B) was 38.7mg and 17g for polyethylene glycol. No adverse effects were identified. Therapy with Senna should be the laxative treatment of choice as part of a bowel management program in children with repaired anorectal malformations and constipation, since the stimulation of colonic propulsion waves could lead to stool evacuation without modification of its consistency which can affect fecal continence. I - randomized controlled trial with adequate statistical power. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Differences in taste between three polyethylene glycol preparations: a randomized double-blind study

    PubMed Central

    Lam, Tze J; Mulder, Chris JJ; Felt-Bersma, Richelle JF

    2011-01-01

    Background and aim Patients suffering from chronic constipation require long-term, regular therapy with laxatives. Literature regarding patient preference and acceptance in polyethylene glycol preparations is scarce. Therefore, this research aimed to identify preference between the three polyethylene glycol 3350, namely Molaxole®, Movicol®, and Laxtra Orange®. Furthermore, taste is one of the most important factors leading to patients’ adherence, particularly when the treatment lasts for a long time. Methods In this randomized, cross-over double-blind study, 100 volunteers were recruited by advertisement. The volunteers were invited to taste the preparations and grade the taste using a five-point hedonic scale (extremely poor taste [1] to extremely good taste [5]). The volunteers were then asked to choose the most palatable preparation. Results One hundred volunteers with a mean age of 35 years (range 20–61) were randomized (76 females). Molaxole®, Movicol®, and Laxtra Orange® had a mean hedonic score of 2.76 (SD: 0.82), 2.81 (SD: 0.76) and 3.12 (SD: 0.82) respectively. The hedonic taste score for Laxtra Orange® was significantly better than Molaxole® (P = 0.001) and Movicol® (P = 0.001). No difference was found between Molaxole® and Movicol® (P = 0.61). Molaxole® was the most preferred preparation for 19 volunteers (19%), Movicol® for 24 volunteers (25%) and Laxtra Orange® for 55 volunteers (56%). Two volunteers had no preference. The order in which volunteers tested the preparations had no influence on the taste results. No significant differences in age or gender were observed. Conclusion Laxtra Orange® was most palatable preparation. This may have implications for adherence in patients with chronic constipation. PMID:21949605

  3. Simultaneous small-angle neutron scattering and Fourier transform infrared spectroscopic measurements on cocrystals of syndiotactic polystyrene with polyethylene glycol dimethyl ethers1

    PubMed Central

    Kaneko, Fumitoshi; Seto, Naoki; Sato, Shuma; Radulescu, Aurel; Schiavone, Maria Maddalena; Allgaier, Jürgen; Ute, Koichi

    2016-01-01

    Syndiotactic polystyrene (sPS) is a crystalline polymer which has a unique property; it is able to form cocrystals with a wide range of chemical compounds, in which the guest molecules are confined in the vacancies of the host sPS crystalline region. Recently, it has been found that even polyethylene glycol oligomers with a molecular weight of more than several hundreds can be introduced into the sPS crystalline region. It is quite important to know how such a long-chain molecule is stored in the host sPS lattice. To tackle this issue, a new simultaneous measurement method combing small-angle neutron scattering and Fourier transform infrared spectroscopy (SANS/FTIR), which has been recently developed by the authors, was applied to an sPS cocrystal with polyethylene glycol dimethyl ether with a molecular weight of 500 (PEGDME500). The temperature-dependent changes of the SANS profile and FTIR spectrum were followed from room temperature up to 413 K for a one-dimensionally oriented SANS/PEGDME500 cocrystal sample. The intensity of the reflections due to the stacking of crystalline lamellae showed a significant temperature dependence. The two-dimensional pattern in the high Q region of SANS also changed depending on temperature. The combined information obtained by SANS and FTIR suggested that PEGDME500 molecules are distributed in both the crystalline and amorphous regions in the low-temperature region close to room temperature, but they are predominantly included in the amorphous region in the high-temperature region. It was also suggested by the two-dimensional SANS profile that PEGDME500 molecules in the crystalline region have an elongated structure along the thickness direction of the crystalline lamellae. PMID:27738412

  4. A Polymeric Prodrug of 5-Fluorouracil-1-Acetic Acid Using a Multi-Hydroxyl Polyethylene Glycol Derivative as the Drug Carrier

    PubMed Central

    Sun, Xun; Gong, Tao; Zhang, Zhirong

    2014-01-01

    Purpose Macromolecular prodrugs obtained by covalently conjugating small molecular drugs with polymeric carriers were proven to accomplish controlled and sustained release of the therapeutic agents in vitro and in vivo. Polyethylene glycol (PEG) has been extensively used due to its low toxicity, low immunogenicity and high biocompatibility. However, for linear PEG macromolecules, the number of available hydroxyl groups for drug coupling does not change with the length of polymeric chain, which limits the application of PEG for drug conjugation purposes. To increase the drug loading and prolong the retention time of 5-fluorouracil (5-Fu), a macromolecular prodrug of 5-Fu, 5-fluorouracil-1 acid-PAE derivative (5-FA-PAE) was synthesized and tested for the antitumor activity in vivo. Methods PEG with a molecular weight of 38 kDa was selected to synthesize the multi-hydroxyl polyethylene glycol derivative (PAE) through an addition reaction. 5-fluorouracil-1 acetic acid (5-FA), a 5-Fu derivative was coupled with PEG derivatives via ester bond to form a macromolecular prodrug, 5-FA-PAE. The in vitro drug release, pharmacokinetics, in vivo distribution and antitumor effect of the prodrug were investigated, respectively. Results The PEG-based prodrug obtained in this study possessed an exceedingly high 5-FA loading efficiency of 10.58%, much higher than the maximum drug loading efficiency of unmodified PEG with the same molecular weight, which was 0.98% theoretically. Furthermore, 5-FA-PAE exhibited suitable sustained release in tumors. Conclusion This study provides a new approach for the development of the delivery to tumors of anticancer agents with PEG derivatives. PMID:25389968

  5. Biomass Yield and Steviol Glycoside Production in Callus and Suspension Culture of Stevia rebaudiana Treated with Proline and Polyethylene Glycol.

    PubMed

    Gupta, Pratibha; Sharma, Satyawati; Saxena, Sanjay

    2015-06-01

    Enhanced production of steviol glycosides (SGs) was observed in callus and suspension culture of Stevia rebaudiana treated with proline and polyethylene glycol (PEG). To study their effect, yellow-green and compact calli obtained from in vitro raised Stevia leaves were sub-cultured on MS medium supplemented with 2.0 mg l(-1) NAA and different concentrations of proline (2.5-10 mM) and PEG (2.5-10 %) for 2 weeks, and incubated at 24 ± 1 °C and 22.4 μmol m(-2) s(-1) light intensity provided by white fluorescent tubes for 16 h. Callus and suspension culture biomass (i.e. both fresh and dry weight content) was increased with 5 mM proline and 5 % PEG, while at further higher concentrations, they got reduced. Further, quantification of SGs content in callus (collected at 15th day) and suspension culture (collected at 10th and 15th day) treated with and without elicitors was analysed by HPLC. It was observed that chemical stress enhanced the production of SGs significantly. In callus, the content of SGs increased from 0.27 (control) to 1.09 and 1.83 % with 7.5 mM proline and 5 % PEG, respectively, which was about 4.0 and 7.0 times higher than control. However, in the case of suspension culture, the same concentrations of proline and polyethylene glycol enhanced the SG content from 1.36 (control) to 5.03 and 6.38 %, respectively, on 10th day which were 3.7 times and 4.7 times higher than control.

  6. Understanding Thiel Embalming in Pig Kidneys to Develop a New Circulation Model

    PubMed Central

    Willaert, Wouter; De Vos, Marie; Van Hoof, Tom; Delrue, Louke; Pattyn, Piet; D’Herde, Katharina

    2015-01-01

    The quality of tissue preservation in Thiel embalmed bodies varies. Research on the administered embalming volume and its vascular distribution may elucidate one of the mechanisms of tissue preservation and allow for new applications of Thiel embalming. Vascular embalming with (group 1, n = 15) or without (group 2, n = 20) contrast agent was initiated in pig kidneys. The distribution of Thiel embalming solution in group 1 was visualized using computed tomography. The kidneys in both groups were then immersed in concentrated salt solutions to reduce their weight and volume. Afterwards, to mimic a lifelike circulation in the vessels, group 2 underwent pump-driven reperfusion for 120 minutes with either paraffinum perliquidum or diluted polyethylene glycol. The circulation was imaged with computed tomography. All of the kidneys were adequately preserved. The embalming solution spread diffusely in the kidney, but fluid accumulation was present. Subsequent immersion in concentrated salt solutions reduced weight (P < 0.01) and volume (P < 0.01). Reperfusion for 120 minutes was established in group 2. Paraffinum perliquidum filled both major vessels and renal tissue, whereas diluted polyethylene glycol spread widely in the kidney. There were no increases in weight (P = 0.26) and volume (P = 0.79); and pressure further decreased (P = 0.032) after more than 60 minutes of reperfusion with paraffinum perliquidum, whereas there were increases in weight (P = 0.005), volume (P = 0.032) and pressure (P < 0.0001) after reperfusion with diluted polyethylene glycol. Arterial embalming of kidneys results in successful preservation due to complete parenchymatous spreading. More research is needed to determine whether other factors affect embalming quality. Dehydration is an effective method to regain the organs’ initial status. Prolonged vascular reperfusion with paraffinum perliquidum can be established in this model without increases in weight, volume and pressure. PMID:25806527

  7. New formulation of chemical peeling agent: 30% salicylic acid in polyethylene glycol. Absorption and distribution of 14C-salicylic acid in polyethylene glycol applied topically to skin of hairless mice.

    PubMed

    Ueda, Setsuko; Mitsugi, Koichi; Ichige, Kazumi; Yoshida, Kenji; Sakuma, Tomoko; Ninomiya, Shin-ichi; Sudou, Tetsuji

    2002-04-01

    Salicylic acid is used in chemical peeling procedures. However, they have caused many side effects, even salicylism. To achieve a salicylic acid peeling that would be safer for topical use, we recently developed a new formulation consisting of 30% salicylic acid in polyethylene glycol (PEG) vehicle. In an extension of our previous research, we studied the absorption of 30% salicylic acid labeled with 14C in PEG vehicle applied topically to the intact and damaged skin of male hairless mice. An ointment containing 3 mg salicylic acid in 10 mg vehicle was applied to both groups. In animals with intact skin, 1 h after application the plasma concentration of radioactivity was 1665.1 ng eq/ml, significantly lower than the 21437.6 ng eq/ml observed in mice with damaged skin. Microautoradiograms of intact skin showed that the level of radioactivity in the cornified cell layer was similar at 6 h after application. However, in damaged skin, the overall level of radioactivity showed a decrease by 3 h after application. In the carcasses remaining after the treated intact and damaged skin had been removed, 0.09 and 11.38% of the applied radioactivity remained, respectively. These findings confirm that 30% salicylic acid in PEG vehicle is little absorbed through the intact skin of hairless mice, and suggest that salicylism related to absorption through the skin of quantities of topically applied salicylic acid is not likely to occur in humans with intact skin during chemical peeling with this preparation. This new preparation of 30% salicylic acid in PEG vehicle is believed to be safe for application as a chemical peeling agent.

  8. Norway spruce embryogenesis: changes in carbohydrate profile, structural development and response to polyethylene glycol

    PubMed Central

    Hudec, Lukáš; Konrádová, Hana; Hašková, Anna; Lipavská, Helena

    2016-01-01

    Two unrelated, geographically distinct, highly embryogenic lines of Norway spruce (Picea abies (L.) Karst.) were analysed to identify metabolic traits characteristic for lines with good yields of high-quality embryos. The results were compared with corresponding characteristics of a poorly productive line (low embryo yield, scarce high-quality embryos). The following carbohydrate profiles and spectra during maturation, desiccation and germination were identified as promising characteristics for line evaluation: a gradual decrease in total soluble carbohydrates with an increasing sucrose : hexose ratio during maturation; accumulation of raffinose family oligosaccharides resulting from desiccation and their rapid degradation at the start of germination; and a decrease in sucrose, increase in hexoses and the appearance of pinitol with proceeding germination. We propose that any deviation from this profile in an embryonic line is a symptom of inferior somatic embryo development. We further propose that a fatty acid spectrum dominated by linoleic acid (18 : 2) was a common feature of healthy spruce somatic embryos, although it was quite different from zygotic embryos mainly containing oleic acid (18 : 1). The responses of the lines to osmotic stress were evaluated based on comparison of control (without osmoticum) and polyethylene glycol (PEG)-exposed (PEG 4000) variants. Although genetically distinct, both highly embryogenic lines responded in a very similar manner, with the only difference being sensitivity to high concentrations of PEG. At an optimum PEG concentration (3.75 and 5%), which was line specific, negative effects of PEG on embryo germination were compensated for by a higher maturation efficiency so that the application of PEG at an appropriate concentration improved the yield of healthy germinants per gram of initial embryonal mass and accelerated the process. Polyethylene glycol application, however, resulted in no improvement of the poorly productive line. PMID:27052433

  9. In vitro and in vivo metabolism of N-adamantyl substituted urea-based soluble epoxide hydrolase inhibitors.

    PubMed

    Liu, Jun-Yan; Tsai, Hsing-Ju; Morisseau, Christophe; Lango, Jozsef; Hwang, Sung Hee; Watanabe, Takaho; Kim, In-Hae; Hammock, Bruce D

    2015-12-15

    N,N'-disubstituted urea-based soluble epoxide hydrolase (sEH) inhibitors are promising therapeutics for hypertension, inflammation, and pain in multiple animal models. The drug absorption and pharmacological efficacy of these inhibitors have been reported extensively. However, the drug metabolism of these inhibitors is not well described. Here we reported the metabolic profile and associated biochemical studies of an N-adamantyl urea-based sEH inhibitor 1-adamantan-1-yl-3-(5-(2-(2-ethoxyethoxy)ethoxy)pentyl)urea (AEPU) in vitro and in vivo. The metabolites of AEPU were identified by interpretation of liquid chromatography-mass spectrometry (LC-MS), liquid chromatography-tandem mass spectrometry (LC-MS/MS) and/or NMR. In vitro, AEPU had three major positions for phase I metabolism including oxidations on the adamantyl moiety, urea nitrogen atoms, and cleavage of the polyethylene glycol chain. In a rodent model, the metabolites from the hydroxylation on the adamantyl group and nitrogen atom were existed in blood while the metabolites from cleavage of polyethylene glycol chain were not found in urine. The major metabolite found in rodent urine was 3-(3-adamantyl-ureido)-propanoic acid, a presumably from cleavage and oxidation of the polyethylene glycol moiety. All the metabolites found were active but less potent than AEPU at inhibiting human sEH. Furthermore, cytochrome P450 (CYP) 3A4 was found to be a major enzyme mediating AEPU metabolism. In conclusion, the metabolism of AEPU resulted from oxidation by CYP could be shared with other N-adamantyl-urea-based compounds. These findings suggest possible therapeutic roles for AEPU and new strategies for drug design in this series of possible drugs. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Polyethylene glycol plus simethicone in small-bowel preparation for capsule endoscopy.

    PubMed

    Spada, Cristiano; Riccioni, Maria E; Familiari, Pietro; Spera, Gianluca; Pirozzi, Giuseppe A; Marchese, Michele; Bizzotto, Alessandra; Ingrosso, Marcello; Costamagna, Guido

    2010-05-01

    Small-bowel contents can hamper the quality of video-capsule endoscopy (VCE). No standardized protocol has been proposed and overnight fasting remains the proposed preparation for VCE. The aim was to evaluate the effects of 2 regimens of bowel preparation on small intestine cleansing, diagnostic yield and capsule transit times. This is a prospective, randomized, blinded, and controlled study. Sixty patients referred for VCE were randomized into 2 groups. Group A ingested 2l of a polyethylene glycol and simethicone solution 16h before VCE. Group B were instructed to consume a fibre-free diet and allowed to consume clear liquids the day before VCE. The small-bowel cleansing was graded as "complete" if the entire wall was assessable, "incomplete" if more than 50% of the wall was visible, and "insufficient" if less than 50% of the wall was visible. In group A, a "complete", "incomplete" and "insufficient" small-bowel cleansing was achieved in 42%, 39% and 19% of cases respectively. In group B, a "complete", "incomplete" and "insufficient" small-bowel cleansing was achieved in 43%, 33% and 24% of cases respectively. No significant differences were observed between the two groups, regarding small-bowel cleansing level (p=0.65). No differences were also observed in the diagnostic yield (48.2%, 13.8% and 38% vs 65.5%, 6.9% and 27.6% of positive, suspicious and no findings respectively, in groups A and B [p=0.39]) and small-bowel transit times (mean 288min and 299 min in groups A and B respectively [p=0.70]). The results of the present study do not support the use of 2l of a polyethylene glycol and simethicone solution before VCE. Copyright 2009 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  11. Improving of bowel cleansing effect for polyethylene glycol with ascorbic acid using simethicone

    PubMed Central

    Yoo, In Kyung; Jeen, Yoon Tae; Kang, Seung Hun; Lee, Jae Hyung; Kim, Seung Han; Lee, Jae Min; Choi, Hyuk Soon; Kim, Eun Sun; Keum, Bora; Chun, Hoon Jai; Lee, Hong Sik; Kim, Chang Duck

    2016-01-01

    Abstract Background and Aim: Low-volume polyethylene glycol with ascorbic acid (PEG-Asc) use is reported to be as safe and effective as traditional 4-L polyethylene glycol use. However, PEG-Asc produces bubbles, which cause problems during colonoscopy. Data on the effects of using antifoaming agents such as simethicone with PEG-Asc are lacking. The aim of this CONSORT-prospective, randomized, observer-blinded, controlled trial is to compare the quality of bowel preparation and compliance between PEG-Asc users and PEG-Asc plus simethicone users. Methods: Adult outpatients aged 18 to 80 years undergoing colonoscopy were recruited to the study. Two hundred sixty patients were randomly assigned to 1 of 2 treatment arms, PEG-Asc or PEG-Asc plus simethicone. The primary outcome measure was the bowel cleansing quality using Boston bowel preparation scale and bubble scores. The secondary outcome measures were patient tolerability and doctor tolerability. Results: The simethicone group showed superior cleansing results (6–9 Boston scale scores: 99% vs. 84%, <5% bubble scores: 96% vs. 49%, P < 0.001) and fewer gastrointestinal symptoms (abdominal fullness: 24% vs. 55%, colicky pain: 5% vs. 24%, P < 0.001) than the non-simethicone group. Moreover, endoscopist fatigue during colonoscopy was lower in the simethicone group than in the non-simethicone group (1.31 ± 0.75 vs. 2.97 ± 2.14, P < 0.001). Conclusion: PEG-Asc plus simethicone use was more effective and associated with better patient and endoscopist tolerance than PEG-Asc use. Therefore, this combination is recommended as one of the promising methods for bowel preparation before colonoscopy. PMID:27428209

  12. Improving of bowel cleansing effect for polyethylene glycol with ascorbic acid using simethicone: A randomized controlled trial.

    PubMed

    Yoo, In Kyung; Jeen, Yoon Tae; Kang, Seung Hun; Lee, Jae Hyung; Kim, Seung Han; Lee, Jae Min; Choi, Hyuk Soon; Kim, Eun Sun; Keum, Bora; Chun, Hoon Jai; Lee, Hong Sik; Kim, Chang Duck

    2016-07-01

    Low-volume polyethylene glycol with ascorbic acid (PEG-Asc) use is reported to be as safe and effective as traditional 4-L polyethylene glycol use. However, PEG-Asc produces bubbles, which cause problems during colonoscopy. Data on the effects of using antifoaming agents such as simethicone with PEG-Asc are lacking. The aim of this CONSORT-prospective, randomized, observer-blinded, controlled trial is to compare the quality of bowel preparation and compliance between PEG-Asc users and PEG-Asc plus simethicone users. Adult outpatients aged 18 to 80 years undergoing colonoscopy were recruited to the study. Two hundred sixty patients were randomly assigned to 1 of 2 treatment arms, PEG-Asc or PEG-Asc plus simethicone. The primary outcome measure was the bowel cleansing quality using Boston bowel preparation scale and bubble scores. The secondary outcome measures were patient tolerability and doctor tolerability. The simethicone group showed superior cleansing results (6-9 Boston scale scores: 99% vs. 84%, <5% bubble scores: 96% vs. 49%, P < 0.001) and fewer gastrointestinal symptoms (abdominal fullness: 24% vs. 55%, colicky pain: 5% vs. 24%, P < 0.001) than the non-simethicone group. Moreover, endoscopist fatigue during colonoscopy was lower in the simethicone group than in the non-simethicone group (1.31 ± 0.75 vs. 2.97 ± 2.14, P < 0.001). PEG-Asc plus simethicone use was more effective and associated with better patient and endoscopist tolerance than PEG-Asc use. Therefore, this combination is recommended as one of the promising methods for bowel preparation before colonoscopy.

  13. Absorption of phenytoin from rectal suppositories formulated with a polyethylene glycol base.

    PubMed

    Burstein, A H; Fisher, K M; McPherson, M L; Roby, C A

    2000-05-01

    To compare phenytoin pharmacokinetics following administration of an oral suspension and a rectal suppository formulated with a polyethylene glycol base. Unblinded, single-dose, randomized, crossover trial. University-affiliated pharmacokinetics and biopharmaceutics laboratory. Six healthy subjects. Subjects were given a single 200-mg dose of phenytoin as an oral suspension and a rectal suppository separated by a 1-week washout. Blood for plasma phenytoin concentrations was obtained at baseline and 0.5, 1, 2, 4, 6, 8, 10, 12, and 24 hours after administration. Plasma was analyzed by high-performance liquid chromatography (coefficient of variation < 6%) for total phenytoin concentration. Phenytoin maximum concentration (Cmax), time to Cmax (Tmax), time to first measurable concentration (Tlag), and area under the curve from time zero to time of last measurable concentration (AUClast) were estimated for oral and rectal administration by WinNonlin (v 1.1) and compared using Wilcoxon's signed rank test (p<0.05 for statistical significance). Two subjects did not have detectable plasma phenytoin concentrations after rectal administration. For the other four subjects, median rectal Cmax was significantly lower than oral Cmax (0.4 vs 1.9 microg/ml, p=0.028), median rectal Tmax did not differ from oral Tmax (11.9 vs 8.0 hrs, p=0.465), and median rectal AUClast, although highly variable, was significantly lower than oral AUClast (5.4 vs 36.2 microg x hr/ml, p=0.046). No Tlag was seen after oral administration, but with rectal administration the median Tlag was 2 hours. The estimated relative bioavailability of rectal phenytoin suppositories based on AUC0-24 was 4.7%, with individual values ranging from 0-58.3%. It appears that absorption of phenytoin from polyethylene glycol rectal suppositories in healthy subjects is highly variable and unpredictable. Thus this formulation is not recommended.

  14. Fabrication of poly(ethylene glycol) hydrogel microstructures using photolithography

    NASA Technical Reports Server (NTRS)

    Revzin, A.; Russell, R. J.; Yadavalli, V. K.; Koh, W. G.; Deister, C.; Hile, D. D.; Mellott, M. B.; Pishko, M. V.

    2001-01-01

    The fabrication of hydrogel microstructures based upon poly(ethylene glycol) diacrylates, dimethacrylates, and tetraacrylates patterned photolithographically on silicon or glass substrates is described. A silicon/silicon dioxide surface was treated with 3-(trichlorosilyl)propyl methacrylate to form a self-assembled monolayer (SAM) with pendant acrylate groups. The SAM presence on the surface was verified using ellipsometry and time-of-flight secondary ion mass spectrometry. A solution containing an acrylated or methacrylated poly(ethylene glycol) derivative and a photoinitiator (2,2-dimethoxy-2-phenylacetophenone) was spin-coated onto the treated substrate, exposed to 365 nm ultraviolet light through a photomask, and developed with either toluene, water, or supercritical CO2. As a result of this process, three-dimensional, cross-linked PEG hydrogel microstructures were immobilized on the surface. Diameters of cylindrical array members were varied from 600 to 7 micrometers by the use of different photomasks, while height varied from 3 to 12 micrometers, depending on the molecular weight of the PEG macromer. In the case of 7 micrometers diameter elements, as many as 400 elements were reproducibly generated in a 1 mm2 square pattern. The resultant hydrogel patterns were hydrated for as long as 3 weeks without delamination from the substrate. In addition, micropatterning of different molecular weights of PEG was demonstrated. Arrays of hydrogel disks containing an immobilized protein conjugated to a pH sensitive fluorophore were also prepared. The pH sensitivity of the gel-immobilized dye was similar to that in an aqueous buffer, and no leaching of the dye-labeled protein from the hydrogel microstructure was observed over a 1 week period. Changes in fluorescence were also observed for immobilized fluorophore labeled acetylcholine esterase upon the addition of acetyl acholine.

  15. Differences in taste between three polyethylene glycol preparations: a randomized double-blind study.

    PubMed

    Lam, Tze J; Mulder, Chris Jj; Felt-Bersma, Richelle Jf

    2011-01-01

    Patients suffering from chronic constipation require long-term, regular therapy with laxatives. Literature regarding patient preference and acceptance in polyethylene glycol preparations is scarce. Therefore, this research aimed to identify preference between the three polyethylene glycol 3350, namely Molaxole(®), Movicol(®), and Laxtra Orange(®). Furthermore, taste is one of the most important factors leading to patients' adherence, particularly when the treatment lasts for a long time. In this randomized, cross-over double-blind study, 100 volunteers were recruited by advertisement. The volunteers were invited to taste the preparations and grade the taste using a five-point hedonic scale (extremely poor taste [1] to extremely good taste [5]). The volunteers were then asked to choose the most palatable preparation. One hundred volunteers with a mean age of 35 years (range 20-61) were randomized (76 females). Molaxole(®), Movicol(®), and Laxtra Orange(®) had a mean hedonic score of 2.76 (SD: 0.82), 2.81 (SD: 0.76) and 3.12 (SD: 0.82) respectively. The hedonic taste score for Laxtra Orange(®) was significantly better than Molaxole(®) (P = 0.001) and Movicol(®) (P = 0.001). No difference was found between Molaxole(®) and Movicol(®) (P = 0.61). Molaxole(®) was the most preferred preparation for 19 volunteers (19%), Movicol(®) for 24 volunteers (25%) and Laxtra Orange(®) for 55 volunteers (56%). Two volunteers had no preference. The order in which volunteers tested the preparations had no influence on the taste results. No significant differences in age or gender were observed. Laxtra Orange(®) was most palatable preparation. This may have implications for adherence in patients with chronic constipation.

  16. Colonoscopy preparation: polyethylene glycol with Gatorade is as safe and efficacious as four liters of polyethylene glycol with balanced electrolytes.

    PubMed

    McKenna, Thomas; Macgill, Alice; Porat, Gail; Friedenberg, Frank K

    2012-12-01

    Four liters of polyethylene glycol 3350 (PEG) with balanced electrolytes for colonoscopy preparation has had poor acceptance. Another approach is the use of electrolyte-free PEG combined with 1.9 L of Gatorade. Despite its widespread use, there are no data on metabolic safety and minimal data on efficacy. Our aim was to assess the efficacy and electrolyte safety of these two PEG-based preparations. This was a prospective, randomized, single-blind, non-inferiority trial. Patients were randomized to 238 g PEG + 1.9 L Gatorade or 4 L of PEG-ELS containing 236 g PEG. Split dosing was not performed. On procedure day blood was drawn for basic chemistries. The primary outcome was preparation quality from procedure photos using the Boston Bowel Preparation Scale. We randomized 136 patients (66 PEG + Gatorade, 70 PEG-ELS). There were no differences in preparation scores between the two agents in the ITT analysis (7.2 ± 1.9 for PEG-ELS and 7.0 ± 2.1 for PEG + Gatorade; p = 0.45). BBPS scores were identical for those who completed the preparation and dietary instructions as directed (7.4 ± 1.7 for PEG-ELS, and 7.4 ± 1.8 for PEG + Gatorade; p = 0.98). There were no statistical differences in serum electrolytes between the two preparations. Patients who received PEG + Gatorade gave higher overall satisfaction scores for the preparation experience (p = 0.001), and had fewer adverse effects. Use of 238 g PEG + 1.9 L Gatorade appears to be safe, better tolerated, and non-inferior to 4 L PEG-ELS. This preparation may be especially useful for patients who previously tolerated PEG-ELS poorly.

  17. Comparison of a low dose polyethylene glycol electrolyte solution with lactulose for treatment of chronic constipation

    PubMed Central

    Attar, A; Lemann, M; Ferguson, A; Halphen, M; Boutron, M; Flourie, B; Alix, E; Salmeron, M; Guillemot, F; Chaussade, S; Menard, A; Moreau, J; Naudin, G; Barthet, M

    1999-01-01

    Background—Polyethylene glycol (PEG) 3350 is a non-absorbable, non-metabolised osmotic agent used in lavage solutions for gut cleansing. 
Aims—To compare the efficacy of PEG and lactulose in chronic constipation. 
Methods—A total of 115 patients with chronic constipation entered a multicentre, randomised, comparative trial. They initially received two sachets containing either PEG (13 g/sachet) or lactulose (10 g/sachet) and were given an option to change the dose to one or three sachets/day, depending on response. 
Results—Ninety nine patients completed the trial. After four weeks, patients in the PEG group (n=50) had a higher number of stools and a lower median daily score for straining at stool than patients in the lactulose group (n=49). Overall improvement was greater in the PEG group. Clinical tolerance was similar in the two groups, but flatus was less frequently reported in the PEG group. The mean number of liquid stools was higher in the PEG group but the difference was significant only for the first two weeks. There were no serious adverse events and no significant change in laboratory tests in either group. At the end of the study, the number of sachets used by the patients was 1.6 (0.7)/day in the PEG group and 2.1 (0.7)/day in the lactulose group. Sixty one patients completed a further two months open study of one to three sachets PEG daily; there was no loss of efficacy and no serious toxicity. 
Conclusion—Low dose PEG 3350 was more effective than lactulose and better tolerated. 

 Keywords: constipation; polyethylene glycol; lactulose; cathartics; randomised trial PMID:9895382

  18. Colonoscopy Preparation: Polyethylene Glycol with Gatorade is as Safe and Efficacious as 4 Liters of Polyethylene Glycol with Balanced Electrolytes

    PubMed Central

    McKenna, Thomas; Macgill, Alice; Porat, Gail; Friedenberg, Frank K.

    2013-01-01

    Background Four liters of polyethylene glycol 3350 with balanced electrolytes for colonoscopy preparation has had poor acceptance. Another approach is the use of electrolyte-free PEG combined with 1.9L of Gatorade. Despite its widespread use, there are no data on metabolic safety and minimal data on efficacy. Our aim was to assess the efficacy and electrolyte safety of these two PEG-based preparations. Methods This was a prospective, randomized, single-blind, non-inferiority trial. Patients were randomized to 238g PEG + 1.9L Gatorade or 4L of PEG-ELS containing 236g PEG. Split dosing was not performed. On procedure day blood was drawn for basic chemistries. The primary outcome was preparation quality from procedure photos using the Boston Bowel Preparation Scale. Results We randomized 136 patients (66 PEG + Gatorade, 70 PEG-ELS). There were no differences in preparation scores between the two agents in the ITT analysis (7.2 ± 1.9 for PEG-ELS and 7.0 ± 2.1 for PEG + Gatorade; p = 0.45). BBPS scores were identical for those who completed the preparation and dietary instructions as directed (7.4 ± 1.7 for PEG-ELS, and 7.4 ± 1.8 for PEG + Gatorade; p = 0.98). There were no statistical differences in serum electrolytes between the two preparations. Patients who received PEG + Gatorade gave higher overall satisfaction scores for the preparation experience (p = 0.001), and had fewer adverse effects. Conclusions Use of 238g PEG + 1.9L Gatorade appears to be safe, better tolerated, and non-inferior to 4L PEG-ELS. This preparation may be especially useful for patients who previously tolerated PEG-ELS poorly. PMID:22711499

  19. Transferrin receptor-targeted pH-sensitive micellar system for diminution of drug resistance and targetable delivery in multidrug-resistant breast cancer

    PubMed Central

    Gao, Wei; Ye, Guihua; Duan, Xiaochuan; Yang, Xiaoying; Yang, Victor C

    2017-01-01

    The emergence of drug resistance is partially associated with overproduction of transferrin receptor (TfR). To overcome multidrug resistance (MDR) and achieve tumor target delivery, we designed a novel biodegradable pH-sensitive micellar system modified with HAIYPRH, a TfR ligand (7pep). First, the polymers poly(l-histidine)-coupled polyethylene glycol-2000 (PHIS-PEG2000) and 7pep-modified 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-polyethylene glycol-2000 (7pep-DSPE-PEG2000) were synthesized, and the mixed micelles were prepared by blending of PHIS-PEG2000 and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-polyethylene glycol-2000 (DSPE-PEG2000) or 7pep-DSPE-PEG2000 (7-pep HD micelles). The micelles exhibited good size uniformity, high encapsulation efficiency, and a low critical micelle concentration. By changing the polymer ratio in the micellar formulation, the pH response range was specially tailored to pH ~6.0. When loaded with antitumor drug doxorubicin (DOX), the micelle showed an acid pH-triggering drug release profile. The cellular uptake and cytotoxicity study demonstrated that 7-pep HD micelles could significantly enhance the intracellular level and antitumor efficacy of DOX in multidrug-resistant cells (MCF-7/Adr), which attributed to the synergistic effect of poly(l-histidine)-triggered endolysosom escape and TfR-mediated endocytosis. Most importantly, the in vivo imaging study confirmed the target-ability of 7-pep HD micelles to MDR tumor. These findings indicated that 7-pep HD micelles would be a promising drug delivery system in the treatment of drug-resistant tumors. PMID:28223798

  20. Metal reduction at point-of-use filtration

    NASA Astrophysics Data System (ADS)

    Umeda, Toru; Daikoku, Shusaku; Varanasi, Rao; Tsuzuki, Shuichi

    2016-03-01

    We explored the metal removal efficiency of Nylon 6,6 and HDPE (High Density Polyethylene) membrane based filters, in solvents of varying degree of polarity such as Cyclohexanone and 70:30 mixture of PGME (Propylene Glycol Monomethyl Ether) and PGMEA (Propylene Glycol Monomethyl Ether), In all the solvents tested, Nylon 6,6 membrane filtration was found to be significantly more effective in removing metals than HDPE membranes, regardless of their respective membrane pore sizes. Hydrophilic interaction chromatography (HILIC) mechanism was invoked to rationalize metal removal efficiency dependence on solvent hydrophobicity.

  1. Novel polyethylene glycol derivative suitable for the preparation of mono-PEGylated protein.

    PubMed

    Yun, Qiang; Chen, Ting; Zhang, Guifeng; Bi, Jingxiu; Ma, Guanghui; Su, Zhiguo

    2005-02-01

    A novel methoxypolyethylene glycol (mPEG) derivative, containing a reactive group of 1-methyl pyridinium toluene-4-sulfonate, was synthesized and characterized. The mPEG derivative was successfully conjugated with two proteins: recombinant human granulocyte-colony stimulating factor (rhG-CSF) and consensus interferon (C-IFN). Homogeneous mono-PEGylated proteins were obtained which were identified by high performance size-exclusion chromatography and MALDI-TOF mass spectrometry. The biological activities of the mono-PEGylated rhG-CSF and the mono-PEGylated C-IFN were maintained at 90% and 88%, respectively.

  2. Characterization of protein release from photocrosslinkable hyaluronic acid-polyethylene glycol hydrogel tissue engineering scaffolds.

    PubMed

    Leach, Jennie B; Schmidt, Christine E

    2005-01-01

    The goal of this work was to utilize the naturally derived bioactive polymer hyaluronic acid (HA) to create a combination tissue engineering scaffold and protein delivery device. HA is a non-immunogenic, non-adhesive glycosaminoglycan that plays significant roles in several cellular processes, including angiogenesis and the regulation of inflammation. In previous work, we created photopolymerizable glycidyl methacrylate-hyaluronic acid (GMHA) hydrogels that had controlled degradation rates, were cytocompatible, and were able to be modified with peptide moieties. In the present studies, we characterized the release of a model protein, bovine serum albumin (BSA), from GMHA and GMHA-polyethylene glycol (PEG) hydrogels. Although BSA could be released rapidly (> 60% within 6 h) from 1% GMHA hydrogels, we found that increasing either the GMHA or the PEG concentrations could lengthen the duration of protein delivery. Preliminary size exclusion chromatography studies indicated that the released BSA was almost entirely in its native monomeric form. Lastly, protein release was extended to several weeks by suspending BSA-poly(lactic-co-glycolic acid) microspheres within the hydrogel bulk. These initial studies indicate that the naturally derived biopolymer HA can be employed to design novel photopolymerizable composites that are suitable for delivering stable proteins from scaffolding in tissue engineering applications.

  3. Polyethylene glycol coated CoFe{sub 2}O{sub 4} nanoparticles: A potential spinel ferrite for biomedical applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Humbe, Ashok V.; Birajdar, Shankar D.; Jadhav, K. M., E-mail: drjadhavkm@gmail.com

    2015-06-24

    The structural and magnetic properties of the polyethylene glycol (PEG) coated cobalt spinel ferrite (CoFe{sub 2}O{sub 4}) nanoparticles have been reported in the present study. CoFe{sub 2}O{sub 4} nanoparticles were prepared by sol-gel auto-combustion method using citric acid + ethylene glycol as a fuel. The prepared powder of cobalt ferrite nanoparticles was annealed at 600°C for 6h and used for further study. The structural characterization of CoFe{sub 2}O{sub 4} nanoparticles were carried out by X-ray diffraction technique. The X-ray analysis confirmed the formation of single phase cubic spinel structure. The crystallite size, Lattice constant and X-ray density of the PEGmore » coated CoFe{sub 2}O{sub 4} nanoparticles were calculated by using XRD data. The presence of PEG on CoFe{sub 2}O{sub 4} nanoparticles and reduced agglomeration in the CoFe{sub 2}O{sub 4} nanoparticles were revealed by SEM studies. The magnetic properties were studied by pulse field hysteresis loop tracer technique at a room temperature. The magnetic parameters such as saturation magnetization, remanence magnetization, coercivity etc have been obtained. These magnetic parameters were get decreased by PEG coating.« less

  4. Dual tumor-targeted poly(lactic-co-glycolic acid)–polyethylene glycol–folic acid nanoparticles: a novel biodegradable nanocarrier for secure and efficient antitumor drug delivery

    PubMed Central

    Chen, Jia; Wu, Qi; Luo, Li; Wang, Yi; Zhong, Yuan; Dai, Han-Bin; Sun, Da; Luo, Mao-Ling; Wu, Wei; Wang, Gui-Xue

    2017-01-01

    Further specific target-ability development of biodegradable nanocarriers is extremely important to promote their security and efficiency in antitumor drug-delivery applications. In this study, a facilely prepared poly(lactic-co-glycolic acid) (PLGA)–polyethylene glycol (PEG)–folic acid (FA) copolymer was able to self-assemble into nanoparticles with favorable hydrodynamic diameters of around 100 nm and negative surface charge in aqueous solution, which was expected to enhance intracellular antitumor drug delivery by advanced dual tumor-target effects, ie, enhanced permeability and retention induced the passive target, and FA mediated the positive target. Fluorescence-activated cell-sorting and confocal laser-scanning microscopy results confirmed that doxorubicin (model drug) loaded into PLGA-PEG-FA nanoparticles was able to be delivered efficiently into tumor cells and accumulated at nuclei. In addition, all hemolysis, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, and zebrafish-development experiments demonstrated that PLGA-PEG-FA nanoparticles were biocompatible and secure for biomedical applications, even at high polymer concentration (0.1 mg/mL), both in vitro and in vivo. Therefore, PLGA-PEG-FA nanoparticles provide a feasible controlled-release platform for secure and efficient antitumor drug delivery. PMID:28848351

  5. Acid-Sensitive Sheddable PEGylated PLGA Nanoparticles Increase the Delivery of TNF-α siRNA in Chronic Inflammation Sites

    PubMed Central

    Aldayel, Abdulaziz M; Naguib, Youssef W; O'Mary, Hannah L; Li, Xu; Niu, Mengmeng; Ruwona, Tinashe B; Cui, Zhengrong

    2016-01-01

    There has been growing interest in utilizing small interfering RNA (siRNA) specific to pro-inflammatory cytokines, such as tumor necrosis factor-α ( TNF-α), in chronic inflammation therapy. However, delivery systems that can increase the distribution of the siRNA in chronic inflammation sites after intravenous administration are needed. Herein we report that innovative functionalization of the surface of siRNA-incorporated poly (lactic-co-glycolic) acid (PLGA) nanoparticles significantly increases the delivery of the siRNA in the chronic inflammation sites in a mouse model. The TNF-α siRNA incorporated PLGA nanoparticles were prepared by the standard double emulsion method, but using stearoyl-hydrazone-polyethylene glycol 2000, a unique acid-sensitive surface active agent, as the emulsifying agent, which renders (i) the nanoparticles PEGylated and (ii) the PEGylation sheddable in low pH environment such as that in chronic inflammation sites. In a mouse model of lipopolysaccharide-induced chronic inflammation, the acid-sensitive sheddable PEGylated PLGA nanoparticles showed significantly higher accumulation or distribution in chronic inflammation sites than PLGA nanoparticles prepared with an acid-insensitive emulsifying agent (i.e., stearoyl-amide-polyethylene glycol 2000) and significantly increased the distribution of the TNF-α siRNA incorporated into the nanoparticles in inflamed mouse foot. PMID:27434685

  6. Polyethylene glycol binding alters human telomere G-quadruplex structure by conformational selection

    PubMed Central

    Buscaglia, Robert; Miller, M. Clarke; Dean, William L.; Gray, Robert D.; Lane, Andrew N.; Trent, John O.; Chaires, Jonathan B.

    2013-01-01

    Polyethylene glycols (PEGs) are widely used to perturb the conformations of nucleic acids, including G-quadruplexes. The mechanism by which PEG alters G-quadruplex conformation is poorly understood. We describe here studies designed to determine how PEG and other co-solutes affect the conformation of the human telomeric quadruplex. Osmotic stress studies using acetonitrile and ethylene glycol show that conversion of the ‘hybrid’ conformation to an all-parallel ‘propeller’ conformation is accompanied by the release of about 17 water molecules per quadruplex and is energetically unfavorable in pure aqueous solutions. Sedimentation velocity experiments show that the propeller form is hydrodynamically larger than hybrid forms, ruling out a crowding mechanism for the conversion by PEG. PEGs do not alter water activity sufficiently to perturb quadruplex hydration by osmotic stress. PEG titration experiments are most consistent with a conformational selection mechanism in which PEG binds more strongly to the propeller conformation, and binding is coupled to the conformational transition between forms. Molecular dynamics simulations show that PEG binding to the propeller form is sterically feasible and energetically favorable. We conclude that PEG does not act by crowding and is a poor mimic of the intranuclear environment, keeping open the question of the physiologically relevant quadruplex conformation. PMID:23804761

  7. Kinetics and mechanism for the sonochemical degradation of a nonionic surfactant.

    PubMed

    Singla, Ritu; Grieser, Franz; Ashokkumar, Muthupandian

    2009-03-26

    The sonolytic degradation of the nonionic surfactant, octaethylene glycol monododecyl ether (C(12)E(8)), has been studied at various initial concentrations below and above its critical micelle concentration (CMC). It has been observed that the degradation rate increases with an increase in the initial concentration of the surfactant until the CMC is reached. Above the CMC an almost constant degradation rate is observed, suggesting that the surfactant in its monomer form is involved in the degradation process. The degradation process of C(12)E(8) involves two distinct primary processes occurring at the bubble/solution interface: (a) hydroxylation/oxidation of the surfactant and (b) pyrolytic fragmentation of the surfactant. The oxidative cleavage of ethylene oxide units provides evidence for OH radical attack. Hydroxylation of the ethoxy chain gives rise to various short-chain carboxyalkyl-polyethylene glycol intermediates. The polyethylene glycol chain formed, due to the scission of the C(12)E(8) molecule, undergoes rapid hydroxylation/oxidation to yield simple compounds that have the potential to undergo further degradation. The detection of multiple intermediates indicates that several processes affect the complete degradation pathways of the surfactant molecule. TOC analysis, however, indicates that the sonolytic mineralization of the surfactant is difficult to achieve at reasonable rates due to the relatively low surface activity of the degradation products formed during sonolysis.

  8. Protein adsorption and cell adhesion on nanoscale bioactive coatings formed from poly(ethylene glycol) and albumin microgels

    PubMed Central

    Scott, Evan A.; Nichols, Michael D.; Cordova, Lee H.; George, Brandon J.; Jun, Young-Shin; Elbert, Donald L.

    2008-01-01

    Late-term thrombosis on drug-eluting stents is an emerging problem that might be addressed using extremely thin, biologically-active hydrogel coatings. We report a dip-coating strategy to covalently link poly(ethylene glycol) (PEG) to substrates, producing coatings with <≈100 nm thickness. Gelation of PEG-octavinylsulfone with amines in either bovine serum albumin (BSA) or PEG-octaamine was monitored by dynamic light scattering (DLS), revealing the presence of microgels before macrogelation. NMR also revealed extremely high end group conversions prior to macrogelation, consistent with the formation of highly crosslinked microgels and deviation from Flory-Stockmayer theory. Before macrogelation, the reacting solutions were diluted and incubated with nucleophile-functionalized surfaces. Using optical waveguide lightmode spectroscopy (OWLS) and quartz crystal microbalance with dissipation (QCM-D), we identified a highly hydrated, protein-resistant layer with a thickness of approximately 75 nm. Atomic force microscopy in buffered water revealed the presence of coalesced spheres of various sizes but with diameters less than about 100 nm. Microgel-coated glass or poly(ethylene terephthalate) exhibited reduced protein adsorption and cell adhesion. Cellular interactions with the surface could be controlled by using different proteins to cap unreacted vinylsulfone groups within the coating. PMID:18771802

  9. Synthesis, characterization and applications of carboxylated and polyethylene-glycolated bifunctionalized InP/ZnS quantum dots in cellular internalization mediated by cell-penetrating peptides.

    PubMed

    Liu, Betty R; Winiarz, Jeffrey G; Moon, Jong-Sik; Lo, Shih-Yen; Huang, Yue-Wern; Aronstam, Robert S; Lee, Han-Jung

    2013-11-01

    Semiconductor nanoparticles, also known as quantum dots (QDs), are widely used in biomedical imaging studies and pharmaceutical research. Cell-penetrating peptides (CPPs) are a group of small peptides that are able to traverse cell membrane and deliver a variety of cargoes into living cells. CPPs deliver QDs into cells with minimal nonspecific absorption and toxic effect. In this study, water-soluble, monodisperse, carboxyl-functionalized indium phosphide (InP)/zinc sulfide (ZnS) QDs coated with polyethylene glycol lipids (designated QInP) were synthesized for the first time. The physicochemical properties (optical absorption, fluorescence and charging state) and cellular internalization of QInP and CPP/QInP complexes were characterized. CPPs noncovalently interact with QInP in vitro to form stable CPP/QInP complexes, which can then efficiently deliver QInP into human A549 cells. The introduction of 500nM of CPP/QInP complexes and QInP at concentrations of less than 1μM did not reduce cell viability. These results indicate that carboxylated and polyethylene-glycolylated (PEGylated) bifunctionalized QInP are biocompatible nanoparticles with potential for use in biomedical imaging studies and drug delivery applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Assembling of stimuli-responsive tumor targeting polypyrrole nanotubes drug carrier system for controlled release.

    PubMed

    Chen, Jian; Li, Xiufang; Li, Jiawen; Li, Jianbing; Huang, Ling; Ren, Tao; Yang, Xiao; Zhong, Shian

    2018-08-01

    A stimuli-responsive polypyrrole (PPy) nanotubes drug carrier system has been designed to deliver anticancer drugs to tumor cells in a targeted and controlled manner. The PPy nanotubes drug carrier was fabricated by a template method. The nanotubes surface was functionalized with cleavable acylhydrazone and disulfide bonds by attaching thiolated β-cyclodextrin (β-CD). The solubilizing poly(ethylene glycol) polymer (PEG), attached with an adamantane (Ad) entity at one end and a folate (FA) entity at the other end, was introduced onto the nanotubes surface via β-cyclodextrin-adamantane interaction. The synthesized FA-PEG-Ad-β-CD-PPy showed excellent biocompatibility and low cytotoxicity for two cell lines. Doxorubicin (Dox) loaded FA-PEG-Ad-β-CD-PPy nanotubes showed a triggered in vitro drug release behavior in the presence of acidic media and reducing agents. The folate-mediated endocytosis and intracellular release of Dox-loaded nanoparticles were confirmed by fluorescence microscopy and cell viability evaluations. In the in vitro study, Dox loaded within the nanoparticles showed enhanced selectivity for cancerous cells and reduced cytotoxicity for normal cells compared to free Dox. The PPy based targeted drug vehicle shows excellent promise for drug delivery. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Probing the Conformational Landscape of a Polyether Building Block by Raman Jet Spectroscopy

    NASA Astrophysics Data System (ADS)

    Bocklitz, Sebastian; Suhm, Martin A.

    2015-06-01

    Polyethylene oxides (Polyethylene glycoles) represent a prominent class of water-soluble polymers. Surprisingly, already 1,2-dimethoxyethane as the simplest representative of this polymer family has an undetermined conformational preference in the gas phase. Here, we address this problem by spontaneous Raman scattering in a supersonic jet. Variation of carrier gas, stagnation pressure, nozzle distance and temperature provides information on the three lowest conformations and their mutual interconversion during collisions in the expansion. The results are compared to quantum chemical calculations of the potential energy landscape and of normal modes.

  12. Microwave-Assisted Synthesis of Nanomaterials and Nanocomposites

    EPA Science Inventory

    The aqueous preparation of nanoparticles using vitamins B1 and B2, and vitamin C which can function both as reducing and capping agents prompted us accomplished the bulk syntheses of Ag and Fe nanorods using polyethylene glycol (PEG) under microwave (MW) irradiation conditions; t...

  13. Live RB51 vaccine lyophilized hydrogel formulations with increased shelf life for practical ballistic delivery

    USDA-ARS?s Scientific Manuscript database

    Ballistic delivery capability is essential to delivering vaccines and other therapeutics effectively to both livestock and wildlife in many global scenarios. Here, lyophilized poly(ethylene glycol) (PEG)-glycolide dimethacrylate crosslinked but degradable hydrogels were assessed as payload vehicles ...

  14. EFFECT OF CHLORINE TREATMENT ON INFECTIVITY OF HEPATITIS A VIRUS

    EPA Science Inventory

    This study examined the effect of chlorine treatment on the infectivity of hepatitis A virus (HAV). Prodromal chimpanzee feces, shown to induce hepatitis in marmosets (Saguinus sp.), was clarified, and the virus was precipitated with 7% polyethylene glycol 6000, harvested and res...

  15. Extremely stretchable thermosensitive hydrogels by introducing slide-ring polyrotaxane cross-linkers and ionic groups into the polymer network.

    PubMed

    Bin Imran, Abu; Esaki, Kenta; Gotoh, Hiroaki; Seki, Takahiro; Ito, Kohzo; Sakai, Yasuhiro; Takeoka, Yukikazu

    2014-10-08

    Stimuli-sensitive hydrogels changing their volumes and shapes in response to various stimulations have potential applications in multiple fields. However, these hydrogels have not yet been commercialized due to some problems that need to be overcome. One of the most significant problems is that conventional stimuli-sensitive hydrogels are usually brittle. Here we prepare extremely stretchable thermosensitive hydrogels with good toughness by using polyrotaxane derivatives composed of α-cyclodextrin and polyethylene glycol as cross-linkers and introducing ionic groups into the polymer network. The ionic groups help the polyrotaxane cross-linkers to become well extended in the polymer network. The resulting hydrogels are surprisingly stretchable and tough because the cross-linked α-cyclodextrin molecules can move along the polyethylene glycol chains. In addition, the polyrotaxane cross-linkers can be used with a variety of vinyl monomers; the mechanical properties of the wide variety of polymer gels can be improved by using these cross-linkers.

  16. Extremely stretchable thermosensitive hydrogels by introducing slide-ring polyrotaxane cross-linkers and ionic groups into the polymer network

    PubMed Central

    Bin Imran, Abu; Esaki, Kenta; Gotoh, Hiroaki; Seki, Takahiro; Ito, Kohzo; Sakai, Yasuhiro; Takeoka, Yukikazu

    2014-01-01

    Stimuli-sensitive hydrogels changing their volumes and shapes in response to various stimulations have potential applications in multiple fields. However, these hydrogels have not yet been commercialized due to some problems that need to be overcome. One of the most significant problems is that conventional stimuli-sensitive hydrogels are usually brittle. Here we prepare extremely stretchable thermosensitive hydrogels with good toughness by using polyrotaxane derivatives composed of α-cyclodextrin and polyethylene glycol as cross-linkers and introducing ionic groups into the polymer network. The ionic groups help the polyrotaxane cross-linkers to become well extended in the polymer network. The resulting hydrogels are surprisingly stretchable and tough because the cross-linked α-cyclodextrin molecules can move along the polyethylene glycol chains. In addition, the polyrotaxane cross-linkers can be used with a variety of vinyl monomers; the mechanical properties of the wide variety of polymer gels can be improved by using these cross-linkers. PMID:25296246

  17. d-Fructose Modification Enhanced Internalization of Mixed Micelles in Breast Cancer Cells via GLUT5 Transporters.

    PubMed

    Zhou, Xu; Qin, Xianyan; Gong, Tao; Zhang, Zhi-Rong; Fu, Yao

    2017-07-01

    d-Fructose modified poly(ε-caprolactone)-polyethylene glycol (PCL-PEG-Fru) diblock amphiphile is synthesized via Cu(I)-catalyzed click chemistry, which self-assembles with D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) into PCL-PEG-Fru/TPGS mixed micelles (PPF MM). It has been proven that glucose transporter (GLUT)5 is overexpressed in MCF-7 cells other than L929 cells. In this study, PPF MM exhibit a significantly higher uptake efficiency than fructose-free PCL-PEG-N 3 /TPGS mixed micelles in both 2D MCF-7 cells and 3D tumor spheroids. Also, the presence of free d-fructose competitively inhibits the internalization of PPF MM in MCF-7 cells other than L929 cells. PPF MM show selective tumor accumulation in MCF-7 breast tumor bearing mice xenografts. Taken together, PPF MM represent a promising nanoscale carrier system to achieve GLUT5-mediated cell specific delivery in cancer therapy. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Effect of PEGylation on ligand-based targeting of drug carriers to the vascular wall in blood flow.

    PubMed

    Onyskiw, Peter J; Eniola-Adefeso, Omolola

    2013-09-03

    The blood vessel wall plays a prominent role in the development of many life-threatening diseases and as such is an attractive target for treatment. To target diseased tissue, particulate drug carriers often have their surfaces modified with antibodies or epitopes specific to vascular wall-expressed molecules, along with poly(ethylene glycol) (PEG) to improve carrier blood circulation time. However, little is known about the effect of poly(ethylene glycol) on carrier adhesion dynamics-specifically in blood flow. Here we examine the influence of different molecular weight PEG spacers on particle adhesion in blood flow. Anti-ICAM-1 or Sialyl Lewis(a) were grafted onto polystyrene 2 μm and 500 nm spheres via PEG spacers and perfused in blood over activated endothelial cells at physiological shear conditions. PEG spacers were shown to improve, reduce, or have no effect on the binding density of targeted-carriers depending on the PEG surface conformation, shear rate, and targeting moiety.

  19. Synthesis of Aluminium Nanoparticles in A Water/Polyethylene Glycol Mixed Solvent using μ-EDM

    NASA Astrophysics Data System (ADS)

    Sahu, R. K.; Hiremath, Somashekhar S.

    2017-08-01

    Nanoparticles present a practical way of retaining the results of the property at the atomic or molecular level. Due to the recent use of nanoparticles in scientific, industrial and medical applications, synthesis of nanoparticles and their characterization have become considerably important. Currently, aluminium nanoparticles have attracted significant research attention because of their reasonable cost, unique properties and interdisciplinary emerging applications. The present paper reports the synthesis of aluminium nanoparticles in the mixture of Deionized water (DI water) and Polyethylene Glycol (PEG) using a developed micro-Electrical Discharge Machining (μ-EDM) method. PEG was used as a stabilizer to prevent nanoparticles from agglomeration produced during the μ -EDM process. The synthesized aluminium nanoparticles were examined by Transmission Electron Microscopy (TEM), Energy Dispersive Analysis by X-rays (EDAX) and Selected Area Electron Diffraction (SAED) pattern to determine their size, shape, chemical nature and crystal structure. The average size of the polyhedral aluminium nanoparticles is found to be 196 nm.

  20. PEGylation of zinc nanoparticles amplifies their ability to enhance olfactory responses to odorant

    PubMed Central

    Singletary, Melissa; Hagerty, Samantha; Muramoto, Shin; Daniels, Yasmine; MacCrehan, William A.; Stan, Gheorghe; Lau, June W.; Pustovyy, Oleg; Globa, Ludmila; Morrison, Edward E.; Sorokulova, Iryna

    2017-01-01

    Olfactory responses are intensely enhanced with the addition of endogenous and engineered primarily-elemental small zinc nanoparticles (NPs). With aging, oxidation of these Zn nanoparticles eliminated the observed enhancement. The design of a polyethylene glycol coating to meet storage requirements of engineered zinc nanoparticles is evaluated to achieve maximal olfactory benefit. The zinc nanoparticles were covered with 1000 g/mol or 400 g/mol molecular weight polyethylene glycol (PEG). Non-PEGylated and PEGylated zinc nanoparticles were tested by electroolfactogram with isolated rat olfactory epithelium and odorant responses evoked by the mixture of eugenol, ethyl butyrate and (±) carvone after storage at 278 K (5 oC), 303 K (30 oC) and 323 K (50 oC). The particles were analyzed by atomic force microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and laser Doppler velocimetry. Our data indicate that stored ZnPEG400 nanoparticles maintain physiologically-consistent olfactory enhancement for over 300 days. These engineered Nanoparticles support future applications in olfactory research, sensitive detection, and medicine. PMID:29261701

  1. Thermoresponsiveness of hybrid micelles from poly(ethylene glycol)-block-poly(4-vinylpyridium) cations and SO4(2-) anions in aqueous solutions.

    PubMed

    Wu, Kai; Shi, Linqi; Zhang, Wangqing; An, Yingli; Zhang, Xu; Li, Zhanyong; Zhu, X X

    2006-02-14

    The SO4(2-)-induced micellization of poly(ethylene glycol)-block-poly(4-vinylpyridium) (PEG110-b-P(4-VPH+)35) and the thermoresponsiveness of these hybrid micelles are studied by dynamic and static light scattering. When the concentration of H2SO4 is high enough, PEG110-b-P(4-VPH+)35 forms stable hybrid micelles with an ionic core of P(4-VPH+)35/SO4(2-) and a PEG corona at 25 degrees C. The formation of the hybrid micelles is reversible. A thermodynamic equilibrium exists between the hybrid micelles and PEG110-b-P(4-VPH+)35 unimers. The shifts of the equilibrium are mainly attributed to the variation of the electrostatic energy and entropic energy of the system. Therefore, the temperature can determine the states of the equilibrium, which means that the dissociation or the formation of the hybrid micelles can be triggered by just varying the temperature.

  2. Influence of dendrimer generation and polyethylene glycol length on the biodistribution of PEGylated dendrimers.

    PubMed

    Kojima, Chie; Regino, Celeste; Umeda, Yasuhito; Kobayashi, Hisataka; Kono, Kenji

    2010-01-04

    Dendrimers are a potential drug carrier. Because modification with polyethylene glycol (PEG) is known to improve the blood retention, PEGylated dendrimers have been studied as a useful drug carrier. In this study, three types of PEGylated L-lysine-bearing polyamidoamine dendrimers (PEG2k-Lys-PAMAM (G4), PEG5k-Lys-PAMAM (G4), PEG2k-Lys-PAMAM (G5)) were synthesized, which are composed of a dendrimer of different generations (generations 4 and 5) and PEG chains with different molecular weights (2k and 5k). An acetylated L-lysine-bearing dendrimer was also synthesized as a non-PEGylated dendrimer. Bifunctional diethylenetriaminepentaacetic acid (pSCN-benzyl-DTPA) was bound to the epsilon -amino group of lysine in a dendrimer, to be labeled with radioactive indium-111. These PEGylayed dendrimers showed longer blood retention and lower accumulation in other normal organs such as the kidneys than the non-PEGylated dendrimer. The PEGylated dendrimers with the higher generation and the longer PEG led the greater blood retention.

  3. Supramolecular recognition control of polyethylene glycol modified N-doped graphene quantum dots: tunable selectivity for alkali and alkaline-earth metal ions.

    PubMed

    Yang, Siwei; Sun, Jing; Zhu, Chong; He, Peng; Peng, Zheng; Ding, Guqiao

    2016-02-07

    The graphene quantum dot based fluorescent probe community needs unambiguous evidence about the control on the ion selectivity. In this paper, polyethylene glycol modified N-doped graphene quantum dots (PN-GQDs) were synthesized by alkylation reaction between graphene quantum dots and organic halides. We demonstrate the tunable selectivity and sensitivity by controlling the supramolecular recognition through the length and the end group size of the polyether chain on PN-GQDs. The relationship formulae between the selectivity/detection limit and polyether chains are experimentally deduced. The polyether chain length determines the interaction between the PN-GQDs and ions with different ratios of charge to radius, which in turn leads to a good selectivity control. Meanwhile the detection limit shows an exponential growth with the size of end groups of the polyether chain. The PN-GQDs can be used as ultrasensitive and selective fluorescent probes for Li(+), Na(+), K(+), Mg(2+), Ca(2+) and Sr(2+), respectively.

  4. Extended Solution Gate OFET-based Biosensor for Label-free Glial Fibrillary Acidic Protein Detection with Polyethylene Glycol-Containing Bioreceptor Layer.

    PubMed

    Song, Jian; Dailey, Jennifer; Li, Hui; Jang, Hyun-June; Zhang, Pengfei; Wang, Jeff Tza-Huei; Everett, Allen D; Katz, Howard E

    2017-05-25

    A novel organic field effect transistor (OFET) -based biosensor is described for label-free glial fibrillary acidic protein (GFAP) detection. We report the first use of an extended solution gate structure where the sensing area and the organic semiconductor are separated, and a reference electrode is not needed. Different molecular weight polyethylene glycols (PEGs) are mixed into the bio-receptor layer to help extend the Debye screening length. The drain current change was significantly increased with the help of higher molecular weight PEGs, as they are known to reduce the dielectric constant. We also investigated the sensing performance under different gate voltage (V g ). The sensitivity increased after we decreased V g from -5 V to -2 V, because the lower V g is much closer to the OFET threshold voltage and the influence of attached negatively charged proteins become more apparent. Finally, the selectivity experiments toward different interferents were performed. The stability and selectivity are promising for clinical applications.

  5. Formation of protein complex with the aid of polyethylene glycol for deproteinized natural rubber latex

    NASA Astrophysics Data System (ADS)

    Wei, Lim Keuw; Ing, Wong Kwee; Badri, Khairiah Haji; Ban, Wong Chong

    2013-11-01

    The effect of polyethylene glycol (PEG) as a deproteinizing agent in commercial natural rubber latex (NRL) onto the physicochemical properties of the NRL was investigated. Three types of PEG were used namely PEG200, PEG4000 and PEG20000 (molecular weight of 200, 4000 and 20000 g/mol respectively). The optimum amount of PEG in NRL was determined from viscosity changes, protein content and Fourier Transform Infrared spectroscopy. Level of protein reduction was affected by molecular weight of PEG. The addition of PEG in NRL reduced the protein content of NRL (3.30 %) to the lowest (2.01 %) at 0.40 phr of PEG200 due to more attractive hydrophobic interactions between short chains PEG compared to PEG4000 (2.24%) and PEG20000 (2.15%). This was verified through FTIR spectroscopy analysis by observing the primary and secondary amide peak where PEG4000 has lesser absorption at the region compared to with PEG20000.

  6. Preparation and Characterization of Modified Soda Lignin with Polyethylene Glycol

    PubMed Central

    Zhang, Fangda; Lin, Jian; Zhao, Guangjie

    2016-01-01

    Soda lignin does not have thermal flowing characteristics and it is impossible for it to be further thermally molded. To achieve the fusibility of soda lignin for fiber preparation by melt-spinning, an effective method for soda lignin modification was conducted by cooking it with polyethylene glycol (PEG) 400 at various ratios. The higher the ratio of PEG that was used, the more PEG molecular chains were grafted at the alpha carbon of the soda lignin through ether bonds, resulting in lower thermal transition temperatures and more excellent fusibility. The modified soda lignin with a weight ratio of lignin to PEG of 1:4 exhibited a relative thermal stability of molten viscosity at selected temperatures. Thereafter, the resultant fusible soda lignin was successfully melt-spun into filaments with an average diameter of 33 ± 5 μm, which is smaller than that of some industrial lignins. Accordingly, it is possible to utilize soda lignin to produce fibrous carbonaceous materials. PMID:28773943

  7. Injectable Dopamine-Modified Poly(ethylene glycol) Nanocomposite Hydrogel with Enhanced Adhesive Property and Bioactivity

    PubMed Central

    2015-01-01

    A synthetic mimic of mussel adhesive protein, dopamine-modified four-armed poly(ethylene glycol) (PEG-D4), was combined with a synthetic nanosilicate, Laponite (Na0.7+(Mg5.5Li0.3Si8)O20(OH)4)0.7–), to form an injectable naoncomposite tissue adhesive hydrogel. Incorporation of up to 2 wt % Laponite significantly reduced the cure time while enhancing the bulk mechanical and adhesive properties of the adhesive due to strong interfacial binding between dopamine and Laponite. The addition of Laponite did not alter the degradation rate and cytocompatibility of PEG-D4 adhesive. On the basis of subcutaneous implantation in rat, PEG-D4 nanocomposite hydrogels elicited minimal inflammatory response and exhibited an enhanced level of cellular infiltration as compared to Laponite-free samples. The addition of Laponite is potentially a simple and effective method for promoting bioactivity in a bioinert, synthetic PEG-based adhesive while simultaneously enhancing its mechanical and adhesive properties. PMID:25222290

  8. Peroxide-mediated desulfurization of phosphorothioate oligonucleotides and its prevention.

    PubMed

    Krotz, Achim H; Mehta, Rahul C; Hardee, Gregory E

    2005-02-01

    Desulfurization at the internucleotide phosphorothioate linkage of antisense oligonucleotides (ASOs) in dermatological formulations has been investigated using strong ion exchange chromatography and mass spectroscopy. The formation of phosphate diester linkages appeared to arise from a reaction between the phosphorothioate oligonucleotide and a potent oxidizing agent. Screening of excipients used in the formulation indicated that the cause of desulfurization was related to the presence of polyethylene glycol-derived nonionic surfactants MYRJ 52 or BRIJ 58. Autoxidation of the polyethylene glycol chain is suggested as the probable origin for the observed incompatibility. The ability of various antioxidants to prevent oxidative degradation of ASO-1 in simple test systems and in oil-in-water emulsions is described. It is found that in test systems both lipophilic and hydrophilic antioxidants are effective. However, in cream formulation (oil-in-water emulsions) of ASO-1 the addition of hydrophilic antioxidants L-cysteine or DL-alpha-lipoic acid has been shown to be superior in protecting the oligonucleotide from desulfurization upon storage. Copyright 2004 Wiley-Liss, Inc.

  9. Cryoprotectant choice and analyses of freeze-drying drug suspension of nanoparticles with functional stabilisers.

    PubMed

    Wang, Lulu; Ma, Yingying; Gu, Yu; Liu, Yangyang; Zhao, Juan; Yan, Beibei; Wang, Yancai

    2018-04-19

    Freeze-drying is an effective way to improve long-term physical stability of nanosuspension in drug delivery applications. Nanosuspension also known as suspension of nanoparticles. In this study, the effect of freeze-drying with different cryoprotectants on the physicochemical characteristics of resveratrol (RSV) nanosuspension and quercetin (QUE) nanosuspension was evaluated. D-α-tocopheryl polyethylene glycol succinate (TPGS) and folate-modified distearoylphosphatidyl ethanolamine-polyethylene glycol (DSPE-PEG-FA) were selected as functional stabilisers formulated nanosuspension which were prepared by anti-solvent precipitation method. RSV nanoparticle size and QUE nanoparticle size were about 210 and 110 nm, respectively. The AFM and TEM results of nanosuspension showed uniform and irregular shape particles. After freeze-drying, the optimal concentration of four cryoprotectants was determined by the particle size of re-dispersed nanoparticles. The dissolution profile of drug nanoparticle significantly showed approximately at a 6-8-fold increase dissolution rate. Moreover, TPGS and DSPE-PEG-FA stabilised RSV nanosuspension and QUE nanosuspension samples showed better effect on long-term physical stability.

  10. Effect of additives on adsorption and desorption behavior of xylanase on acid-insoluble lignin from corn stover and wheat straw.

    PubMed

    Li, Yanfei; Ge, Xiaoyan; Sun, Zongping; Zhang, Junhua

    2015-06-01

    The competitive adsorption between cellulases and additives on lignin in the hydrolysis of lignocelluloses has been confirmed, whereas the effect of additives on the interaction between xylanase and lignin is not clear. In this work, the effects of additives, poly(ethylene glycol) 2000, poly(ethylene glycol) 6000, Tween 20, and Tween 80, on the xylanase adsorption/desorption onto/from acid-insoluble lignin from corn stover (CS-lignin) and wheat straw (WS-lignin) were investigated. The results indicated that the additives could adsorb onto isolated lignin and reduce the xylanase adsorption onto lignin. Compared to CS-lignin, more additives could adsorb onto WS-lignin, making less xylanase adsorbed onto WS-lignin. In addition, the additives could enhance desorption of xylanase from lignin, which might be due to the competitive adsorption between xylanase and additives on lignin. The released xylanase from lignin still exhibited hydrolytic capacity in the hydrolysis of isolated xylan and xylan in corn stover. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Concentration of infectious hematopoietic necrosis virus from water samples by tangential flow filtration and polyethylene glycol precipitation

    USGS Publications Warehouse

    Batts, W.N.; Winton, J.R.

    1989-01-01

    Infectious hematopoietic necrosis virus (IHNV) was concentrated from water samples by polyethylene glycol (PEG) precipitation, tangential flow filtration (TFF), and by a combination of TFF followed by PEG precipitation of the retentate. Used alone, PEG increased virus titers more than 200-fold, and the efficiency of recovery was as great as 100%. Used alone, TFF concentrated IHNV more than 20-fold, and average recovery was 70%. When the two techniques were combined, 10-L water samples were reduced to about 300 mL by TFF and the virus was precipitated with PEG into a 1 to 2 g pellet; total recovery was as great as 100%. The combined techniques were used to isolate IHNV from water samples taken from a river containing adult sockeye salmon (Oncorhynchus nerka) and from a hatchery pond containing adult spring chinook salmon (O. tshawytscha). The combination of these methods was effective in concentrating and detecting IHNV from water containing only three infectious particles per 10-L sample.

  12. Antimicrobial polycaprolactone/polyethylene glycol embedded lysozyme coatings of Ti implants for osteoblast functional properties in tissue engineering

    NASA Astrophysics Data System (ADS)

    Visan, A.; Cristescu, R.; Stefan, N.; Miroiu, M.; Nita, C.; Socol, M.; Florica, C.; Rasoga, O.; Zgura, I.; Sima, L. E.; Chiritoiu, M.; Chifiriuc, M. C.; Holban, A. M.; Mihailescu, I. N.; Socol, G.

    2017-09-01

    In this study, coatings based on lysozyme embedded into a matrix of polyethylene glycol (PEG) and polycaprolactone (PCL) were fabricated by two different methods (Matrix Assisted Pulsed Laser Evaporation - MAPLE and Dip Coating) for obtaining antimicrobial coatings envisaged for long term medical applications. Coatings with different PEG:PCL compositions (3:1; 1:1; 1:3) were synthesized in order to evaluate the antimicrobial activity of lysozyme embedded into the polymeric matrix. The main surface features, such as roughness and wettability, with impact on the microbial adhesion as well as on the eukaryote cell function were measured. The obtained composite coatings exhibited a significant antibacterial activity against Escherichia coli, Bacillus subtilis, Enterococcus faecalis and Staphylococcus aureus strains. As well, specific blended coatings showed appropriate viability, good spreading and normal cell morphology of SaOs2 human osteoblasts and mesenchymal stem cells (MSCs). These investigations highlight the suitability of biodegradable composites as implant coatings for decreasing the risk of bacterial contamination associated with prosthetic procedures.

  13. Clonazepam release from bioerodible hydrogels based on semi-interpenetrating polymer networks composed of poly(epsilon-caprolactone) and poly(ethylene glycol) macromer.

    PubMed

    Cho, C S; Han, S Y; Ha, J H; Kim, S H; Lim, D Y

    1999-04-30

    Poly(ethylene glycol)(PEG) macromers terminated with acrylate groups and semi-interpenetrating polymer networks (SIPNs) composed of poly(epsilon-caprolactone)(PCL) and PEG macromer were synthesized to obtain a bioerodible hydrogel. Polymerization of PEG macromer resulted in the formation of cross-linked gels due to the multifunctionality of macromer. Glass transition temperature (Tg) and melting temperature (Tm) of PEG networks and PCL in the SIPNs were inner-shifted, indicating an interpenetration of PCL and PEG chains. Water content in the SIPNs increased with increasing PEG weight fraction due to the hydrophilicity of PEG. The amount of clonazepam (CNZ) released from the SIPNs increased with higher content in the SIPNs, lower drug loading, lower concentration of PEG macromer during the SIPNs preparation, and higher molecular weight of PEG. In particular, a combination with low PEG content and low CNZ solubility in water led to long-term constant release from these matrices in vitro and in vivo. Copyright.

  14. High Performance Solid Polymer Electrolytes for Rechargeable Batteries: A Self‐Catalyzed Strategy toward Facile Synthesis

    PubMed Central

    Cui, Yanyan; Liang, Xinmiao; Chai, Jingchao; Cui, Zili; Wang, Qinglei; He, Weisheng; Liu, Xiaochen; Feng, Jiwen

    2017-01-01

    Abstract It is urgent to seek high performance solid polymer electrolytes (SPEs) via a facile chemistry and simple process. The lithium salts are composed of complex anions that are stabilized by a Lewis acid agent. This Lewis acid can initiate the ring opening polymerization. Herein, a self‐catalyzed strategy toward facile synthesis of crosslinked poly(ethylene glycol) diglycidyl ether‐based solid polymer electrolyte (C‐PEGDE) is presented. It is manifested that the poly(ethylene glycol) diglycidyl ether‐based solid polymer electrolyte possesses a superior electrochemical stability window up to 4.5 V versus Li/Li+ and considerable ionic conductivity of 8.9 × 10−5 S cm−1 at ambient temperature. Moreover, the LiFePO4/C‐PEGDE/Li batteries deliver stable charge/discharge profiles and considerable rate capability. It is demonstrated that this self‐catalyzed strategy can be a very effective approach for high performance solid polymer electrolytes. PMID:29201612

  15. Arsenate reductase from Thermus thermophilus conjugated to polyethylene glycol-stabilized gold nanospheres allow trace sensing and speciation of arsenic ions.

    PubMed

    Politi, Jane; Spadavecchia, Jolanda; Fiorentino, Gabriella; Antonucci, Immacolata; De Stefano, Luca

    2016-10-01

    Water sources pollution by arsenic ions is a serious environmental problem all around the world. Arsenate reductase enzyme (TtArsC) from Thermus thermophilus extremophile bacterium, naturally binds arsenic ions, As(V) and As (III), in aqueous solutions. In this research, TtArsC enzyme adsorption onto hybrid polyethylene glycol-stabilized gold nanoparticles (AuNPs) was studied at different pH values as an innovative nanobiosystem for metal concentration monitoring. Characterizations were performed by UV/Vis and circular dichroism spectroscopies, TEM images and in terms of surface charge changes. The molecular interaction between arsenic ions and the TtArsC-AuNPs nanobiosystem was also monitored at all pH values considered by UV/Vis spectroscopy. Tests performed revealed high sensitivities and limits of detection equal to 10 ± 3 M -12 and 7.7 ± 0.3 M -12 for As(III) and As(V), respectively. © 2016 The Author(s).

  16. High-Resolution Imaging of Polyethylene Glycol Coated Dendrimers via Combined Atomic Force and Scanning Tunneling Microscopy

    PubMed Central

    Zhong, Qian; Yin, Nai-Ning; Karsai, Arpad; da Rocha, Sandro R. P.; Liu, Gang-yu

    2015-01-01

    Dendrimers have shown great promise as drug delivery vehicles in recent years because they can be synthesized with designed size and functionalities for optimal transportation, targeting, and biocompatibility. One of the most well-known termini used for biocompatibility is polyethylene glycol (PEG), whose performance is affected by its actual conformation. However, the conformation of individual PEG bound to soft materials such as dendrimers has not been directly observed. Using atomic force microscopy (AFM) and scanning tunneling microscopy (STM), this work characterizes the structure adopted by PEGylated dendrimers with the highest resolution reported to date. AFM imaging enables visualization of the individual dendrimers, as well as the differentiation and characterization of the dendrimer core and PEG shell. STM provides direct imaging of the PEG extensions with high-resolution. Collectively, this investigation provides important insight into the structure of coated dendrimers, which is crucial for the design and development of better drug delivery vehicles. PMID:25685559

  17. Polyelectrolyte Complex Optimization for Macrophage Delivery of Redox Enzyme Nanoparticles

    PubMed Central

    Zhao, Yuling; Haney, Matthew J.; Klyachko, Natalia L.; Li, Shu; Booth, Stephanie L.; Higginbotham, Sheila M.; Jones, Jocelyn; Zimmerman, Matthew C.; Mosley, R. Lee; Kabanov, Alexander V.; Gendelman, Howard E.; Batrakova, Elena V.

    2011-01-01

    Background We posit that cell-mediated drug delivery can improve transport of therapeutic enzymes to the brain and decrease inflammation and neurodegeneration induced during Parkinson’s disease. Our prior work demonstrated that macrophages loaded with nanoformulated catalase (“nanozyme”) protect the nigrostriatum in a murine model of Parkinson’s disease. Packaging of catalase into block ionomer complex with a synthetic polyelectrolyte block copolymers protects the enzyme degradation in macrophages. Methods We examined relationships between the composition and structure of block ionomer complexes, their physicochemical characteristics, and loadings, release rates, and catalase activity in bone marrow-derived macrophages. Results Formation of block-ionomer complexes resulted in improved aggregation stability. Block ionomer complexes with ε-polylisine, and poly-L-glutamic acid -poly(ethylene glycol) demonstrated the least cytotoxicity and high loading and release rates, however, did not efficiently protect catalase inside macrophages. Conclusion nanozymes with polyethyleneimine- and poly(L-lysine)10-poly(ethylene glycol) provided the best protection of enzymatic activity for cell-mediated drug delivery. PMID:21182416

  18. Plasma-induced graft-polymerization of polyethylene glycol acrylate on polypropylene substrates

    NASA Astrophysics Data System (ADS)

    Zanini, S.; Orlandi, M.; Colombo, C.; Grimoldi, E.; Riccardi, C.

    2009-08-01

    A detailed study of argon plasma-induced graft-polymerization of polyethylene glycol acrylate (PEGA) on polypropylene (PP) substrates (membranes and films) is presented. The process consists of four steps: (a) plasma pre-activation of the PP substrates; (b) immersion in a PEGA solution; (c) argon plasma-induced graft-polymerization; (d) washing and drying of the samples. Influence of the solution and plasma parameters on the process efficiency evaluated in terms of amount of grafted polymer, coverage uniformity and substrates wettability, are investigated. The plasma-induced graft-polymerization of PEGA is then followed by sample weighting, water droplet adsorption time and contact angle measurements, attenuated total reflection infrared spectroscopy (ATR-IR), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) analyses. The stability of the obtained thin films was evaluated in water and in phosphate buffer saline (PBS) at 37 °C. Results clearly indicates that plasma-induced graft-polymerization of PEGA is a practical methodology for anti-fouling surface modification of materials.

  19. Cyclodextrin-PEG conjugate-wrapped magnetic ferrite nanoparticles for enhanced drug loading and release

    NASA Astrophysics Data System (ADS)

    Enoch, Israel V. M. V.; Ramasamy, Sivaraj; Mohiyuddin, Shanid; Gopinath, Packirisamy; Manoharan, R.

    2018-05-01

    Magnetic nanoparticles are envisaged to overcome the impediments in the methods of targeted drug delivery and hence cure cancer effectively. We report herein, manganese ferrite nanoparticles, coated with β-cyclodextrin-modified polyethylene glycol as a carrier for the drug, camptothecin. The particles are of the size of 100 nm and they show superparamagnetic behaviour. The saturation magnetization does not get diminished on polymer coverage of the nanoparticles. The β-cyclodextrin-polyethylene glycol conjugates are characterized using NMR and mass spectrometric techniques. By coating the magnetic nanoparticles with the cyclodextrin-tethered polymer, the drug-loading capacity is enhanced and the observed release of the drug is slow and sustained. The cell viability of HEK293 and HCT15 cells is evaluated and the cytotoxicity is enhanced when the drug is loaded in the polymer-coated magnetic nanoparticles. The noncovalent-binding based and enhanced drug loading on the nanoparticles and the sustained release make the nanocarrier a promising agent for carrying the payload to the target.

  20. Safety Evaluation of Polyethylene Glycol (PEG) Compounds for Cosmetic Use

    PubMed Central

    Shin, Chan Young; Kim, Kyu-Bong

    2015-01-01

    Polyethylene glycols (PEGs) are products of condensed ethylene oxide and water that can have various derivatives and functions. Since many PEG types are hydrophilic, they are favorably used as penetration enhancers, especially in topical dermatological preparations. PEGs, together with their typically nonionic derivatives, are broadly utilized in cosmetic products as surfactants, emulsifiers, cleansing agents, humectants, and skin conditioners. The compounds studied in this review include PEG/PPG-17/6 copolymer, PEG-20 glyceryl triisostearate, PEG-40 hydrogenated castor oil, and PEG-60 hydrogenated castor oil. Overall, much of the data available in this review are on PEGylated oils (PEG-40 and PEG-60 hydrogenated castor oils), which were recommended as safe for use in cosmetics up to 100% concentration. Currently, PEG-20 glyceryl triisostearate and PEGylated oils are considered safe for cosmetic use according to the results of relevant studies. Additionally, PEG/PPG-17/6 copolymer should be further studied to ensure its safety as a cosmetic ingredient. PMID:26191379

  1. Intraspinal Delivery of Polyethylene Glycol-coated Gold Nanoparticles Promotes Functional Recovery After Spinal Cord Injury.

    PubMed

    Papastefanaki, Florentia; Jakovcevski, Igor; Poulia, Nafsika; Djogo, Nevena; Schulz, Florian; Martinovic, Tamara; Ciric, Darko; Loers, Gabrielle; Vossmeyer, Tobias; Weller, Horst; Schachner, Melitta; Matsas, Rebecca

    2015-06-01

    Failure of the mammalian central nervous system (CNS) to regenerate effectively after injury leads to mostly irreversible functional impairment. Gold nanoparticles (AuNPs) are promising candidates for drug delivery in combination with tissue-compatible reagents, such as polyethylene glycol (PEG). PEG administration in CNS injury models has received interest for potential therapy, but toxicity and low bioavailability prevents clinical application. Here we show that intraspinal delivery of PEG-functionalized 40-nm-AuNPs at early stages after mouse spinal cord injury is beneficial for recovery. Positive outcome of hind limb motor function was accompanied by attenuated inflammatory response, enhanced motor neuron survival, and increased myelination of spared or regrown/sprouted axons. No adverse effects, such as body weight loss, ill health, or increased mortality were observed. We propose that PEG-AuNPs represent a favorable drug-delivery platform with therapeutic potential that could be further enhanced if PEG-AuNPs are used as carriers of regeneration-promoting molecules.

  2. Hydrodynamic Microgap Voltammetry under Couette Flow Conditions: Electrochemistry at a Rotating Drum in Viscous Poly(ethylene glycol).

    PubMed

    Hotchen, Christopher E; Nguyen, H Viet; Fisher, Adrian C; Frith, Paul E; Marken, Frank

    2015-07-21

    Electrochemical processes in highly viscous media such as poly(ethylene glycol) (herein PEG200) are interesting for energy-conversion applications, but problematic due to slow diffusion causing low current densities. Here, a hydrodynamic microgap experiment based on Couette flow is introduced for an inlaid disc electrode approaching a rotating drum. Steady-state voltammetric currents are independent of viscosity and readily increased by two orders of magnitude with further potential to go to higher rotation rates and nanogaps. A quantitative theory is derived for the prediction of currents under high-shear Couette flow conditions and generalised for different electrode shapes. The 1,1'-ferrocene dimethanol redox probe in PEG200 (D=1.4×10 -11  m 2  s -1 ) is employed and data are compared with 1) a Levich-type equation expressing the diffusion-convection-limited current and 2) a COMSOL simulation model providing a potential-dependent current trace. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Novel Brassinosteroid-Modified Polyethylene Glycol Micelles for Controlled Release of Agrochemicals.

    PubMed

    Pérez Quiñones, Javier; Brüggemann, Oliver; Kjems, Jørgen; Shahavi, Mohammad Hassan; Peniche Covas, Carlos

    2018-02-21

    Two synthetic analogues of brassinosteroids (DI31 and S7) exhibit good plant growth enhancer activity. However, their hydrophobicity and quick metabolism in plants have limited their application and benefits in agriculture. Our objective was to prepare novel brassinosteroid-modified polyethylene glycol (PEG) micelles to achieve controlled release with extended stability while retaining agrochemical activity. Spectroscopic studies confirmed quantitative disubstitution of studied PEGs with the brassinosteroids, while elemental analysis assessed purity of the synthesized conjugates. Conjugates were also characterized by X-ray diffraction and thermal analysis. Dynamic and static light scattering showed stable and homogeneous approximately spherical micelles with average hydrodynamic diameters of 22-120 nm and almost neutral ζ potential. Spherical 30-140 nm micelles were observed by electron microscopy. Sustained in vitro releases at pH 5.5 were extended up to 96 h. Prepared PEG micelles showed good agrochemical activity in the radish seed bioassay and no cytotoxicity to the human microvascular endothelial cell line in the MTS test.

  4. Use of hydroxypropyl-β-cyclodextrin/polyethylene glycol 400, modified Fe3O4 nanoparticles for congo red removal.

    PubMed

    Yu, Lan; Xue, Weihua; Cui, Lei; Xing, Wen; Cao, Xinli; Li, Hongyu

    2014-03-01

    Fe3O4 nanoparticles were modified with Hydroxypropyl-β-cyclodextrin (HP-β-CD) and Polyethylene glycol 400 (PEG400) by a facile one-pot homogeneous precipitation method, and were used as a novel nano-adsorbent for the removal of congo red (CR) from aqueous solutions. The polymer-modified composites were characterized by FTIR, TEM, TGA, XRD and VSM, and showed excellent adsorption efficiency for CR. The value of the maximum adsorption capacity calculated according to the Langmuir isotherm model were 1.895g/g, which are much high and about 19 times that of Fe3O4 nanoparticles. Desorption study further indicates the good regeneration ability of the nanocomposites. The results suggest that the HP-β-CD/PEG400-modified Fe3O4 nanoparticles is a promising adsorbent for CR removal from aqueous solutions, and it is easily recycled owing to its large specific surface area and unique magnetic responsiveness. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  5. Preparation and investigation of mefenamic acid - polyethylene glycol - sucrose ester solid dispersions.

    PubMed

    Fülöp, Ibolya; Gyéresi, Árpád; Kiss, Lóránd; Deli, Mária A; Croitoru, Mircea Dumitru; Szabó-Révész, Piroska; Aigner, Zoltán

    2015-12-01

    Mefenamic acid (MA) is a widely used non-steroidal antiinflammatory (NSAID) drug. The adverse effects typical of NSAIDs are also present in the case of MA, partly due to its low water solubility. The aim of this study was to increase the water solubility of MA in order to influence its absorption and bioavailability. Solid dispersions of MA were prepared by the melting method using polyethylene glycol 6000 and different types (laurate, D-1216; palmitate, P-1670; stearate, S-1670) and amounts of sucrose esters as carriers. The X-ray diffraction results show that MA crystals were not present in the products. Dissolution tests carried out in artificial intestinal juice showed that the product containing 10 % D-1216 increased water solubility about 3 times. The apparent permeability coefficient of MA across human Caco-2 intestinal epithelial cell layers was high and, despite the difference in solubility, there was no further increase in drug penetration in the presence of the applied additives.

  6. In Vitro Study of Surface Modified Poly(ethylene glycol)-Impregnated Sintered Bovine Bone Scaffolds on Human Fibroblast Cells

    PubMed Central

    Pramanik, Sumit; Ataollahi, Forough; Pingguan-Murphy, Belinda; Oshkour, Azim Ataollahi; Osman, Noor Azuan Abu

    2015-01-01

    Scaffold design from xenogeneic bone has the potential for tissue engineering (TE). However, major difficulties impede this potential, such as the wide range of properties in natural bone. In this study, sintered cortical bones from different parts of a bovine-femur impregnated with biodegradable poly(ethylene glycol) (PEG) binder by liquid phase adsorption were investigated. Flexural mechanical properties of the PEG-treated scaffolds showed that the scaffold is stiffer and stronger at a sintering condition of 1000°C compared with 900°C. In vitro cytotoxicity of the scaffolds evaluated by Alamar Blue assay and microscopic tests on human fibroblast cells is better at 1000°C compared with that at 900°C. Furthermore, in vitro biocompatibility and flexural property of scaffolds derived from different parts of a femur depend on morphology and heat-treatment condition. Therefore, the fabricated scaffolds from the distal and proximal parts at 1000°C are potential candidates for hard and soft TE applications, respectively. PMID:25950377

  7. Unusual kinetics of poly(ethylene glycol) oxidation with cerium(IV) ions in sulfuric acid medium and implications for copolymer synthesis.

    PubMed

    Szymański, Jan K; Temprano-Coleto, Fernando; Pérez-Mercader, Juan

    2015-03-14

    The cerium(IV)-alcohol couple in an acidic medium is an example of a redox system capable of initiating free radical polymerization. When the alcohol has a polymeric nature, the outcome of such a process is a block copolymer, a member of a class of compounds possessing many useful properties. The most common polymer with a terminal -OH group is poly(ethylene glycol) (PEG); however, the detailed mechanism of its reaction with cerium(IV) remains underexplored. In this paper, we report our findings for this reaction based on spectrophotometric measurements and kinetic modeling. We find that both the reaction order and the net rate constant for the oxidation process depend strongly on the nature of the acidic medium used. In order to account for the experimental observations, we postulate that protonation of PEG decreases its affinity for some of the cerium(IV)-sulfate complexes formed in the system.

  8. Capillary isoelectric focusing and fluorometric detection of proteins and microorganisms dynamically modified by poly(ethylene glycol) pyrenebutanoate.

    PubMed

    Horka, Marie; Ruzicka, Filip; Horký, Jaroslav; Holá, Veronika; Slais, Karel

    2006-12-15

    The nonionogenic pyrene-based tenside, poly(ethylene glycol) pyrenebutanoate, was prepared and applied in capillary isoelectric focusing with fluorometric detection. This dye was used here as a buffer additive in capillary isoelectric focusing for a dynamic modification of the sample of proteins and microorganisms. The values of the isoelectric points of the labeled bioanalytes were calculated with use of the fluorescent pI markers and were found comparable with pI of the native compounds. The mixed cultures of proteins and microorganisms, Escherichia coli CCM 3954, Staphylococcus epidermidis CCM 4418, Proteus vulgaris, Enterococcus faecalis CCM 4224, and Stenotrophomonas maltophilia, the strains of the yeast cells, Candida albicans CCM 8180, Candida krusei, Candida parapsilosis, Candida glabrata, Candida tropicalis, and Saccharomyces cerevisiae were reproducibly focused and separated by the suggested technique. Using UV excitation for the on-column fluorometric detection, the minimum detectable amount was down to 10 cells injected on the separation capillary.

  9. Formulation development of allopurinol suppositories and injectables.

    PubMed

    Lee, D K; Wang, D P

    1999-11-01

    Allopurinol was formulated into injectable and suppository dosage forms. The injectable formulation was prepared by dissolving allopurinol in a cosolvent system consisting of dimethyl sulfoxide (DMSO) and propylene glycol (v/v = 50/50). The stability of allopurinol in the cosolvent system was studied under accelerated storage conditions, and results indicate first-order degradation kinetics with an activation energy of 24.3 kcal/mol. The development of suppository dosage forms was performed by formulating allopurinol with polyethylene glycol (PEG) mixtures of different molecular weights. In vitro release profiles of suppositories formulated with different polyethylene bases were obtained in the pH 7.4 buffer solution using the USP 23 paddle method at 100 rpm. Results indicate that the release rate of the suppository formulations containing PEG 1500/PEG 4000 at the ratio (w/w) of 2.5/10 to 10/2.5 appeared to be similar. However, the addition of sodium lauryl sulfate in the suppository decreased the release rate of allopurinol significantly. A future study to establish in vitro/in vivo correlation (iv/ivc) is suggested.

  10. [Isolation and purification of alpha-glycerophosphate oxidase in a polyethylene glycol/(NH4 )2SO4 aqueous two-phase system].

    PubMed

    Meng, Yao; Jin, Jiagui; Liu, Shuangfeng; Yang, Min; Zhang, Qinglian; Wan, Li; Tang, Kun

    2014-02-01

    Alpha-glycerophosphate oxidase (alpha-GPO) from Enterococcus casseli flavus was successfully isolated and purified by using polyethylene glycol (PEG)/(NH4)2SO4 aqueous two-phase system (ATPS). The results showed that the chosen PEG/(NH4)2SO4 ATPS could be affected by PEG molecular weight, pH, concentration of PEG and (NH4)2SO4, and inorganic salt as well as additional amount of crude enzyme. After evaluating these influencing factors, the final optimum purification strategy was formed by 16.5% (m/m) PEG2000, 13.2% (m/m) (NH4)2SO4, pH 7.5 and 30% (m/m) additive crude enzyme, respectively. The NaCl was a negative influencing factor which would lead to lower purification fold and activity recovery. These conditions eventually resulted in the activity recovery of 89% (m/m), distribution coefficient of 1.2 and purification fold of 7.0.

  11. Effect of addition of Proline, ionic liquid [Choline][Pro] on CO2 separation properties of poly(amidoamine) dendrimer / poly(ethylene glycol) hybrid membranes

    NASA Astrophysics Data System (ADS)

    Duan, S. H.; Kai, T.; Chowdhury, F. A.; Taniguchi, I.; Kazama, S.

    2018-01-01

    Poly(amidoamine) (PAMAM) dendrimers were incorporated into cross-linked poly(ethylene glycol) (PEGDMA) matrix to improve carbon dioxide (CO2) separation performance at elevated pressures. In our previous studies, PAMAM/PEGDMA hybrid membranes showed high CO2 separation properties from CO2/H2 mixed gases. In this study, proline, choline and ionic liquid [Choline][Pro] compounds were selected as rate promoters that were used to prepare PAMAM/PEGDMA hybrid membranes. The effect of addition of proline, choline, IL [Choline][Pro] on separation performance of PAMAM/PEGDMA) hybrid membranes for CO2/H2 separation was investigated. Amino acid proline, choline, and IL [Choline][Pro] were used to promote CO2 and amine reaction. With the addition of [Choline][Pro] into PAMAM/PEG membrane, CO2 permeance of PAMAM/PEG hybrid membranes are increased up to 46% without any change of selectivity of membrane for CO2.

  12. Anaphylaxis to Polyethylene Glycol (Colyte®) in a Patient with Diverticulitis.

    PubMed

    Lee, So Hee; Hwang, Sun Hyuk; Park, Jin Soo; Park, Hae Sim; Shin, Yoo Seob

    2016-10-01

    Polyethylene glycols (PEGs) are believed to be chemically inert agents, but larger PEG polymers could have immunogenicity. A 39-year-old man was referred to emergency room for loss of consciousness and dyspnea after taking of PEG-3350 (Colyte®). In laboratory findings, the initial serum tryptase level was increased to 91.9 mg/L (normal range: 0.00-11.40 mg/L) without any other laboratory abnormalities. The intradermal test with 10 mg/mL Colyte® showed a 5 × 5 mm wheal, but basophil activation and histamine releasability tests were negative. PEG-3350 is widely used as an osmotic laxative due to its lack of absorption from the gastrointestinal tract. However, the loss of mucosal integrity at gastrointestinal membrane such as diverticulitis may be a predisposing factor for anaphylaxis to Colyte®. We report a case of anaphylaxis induced by the ingestion of PEG-3350 in a patient with diverticulitis which might be a risk factor of anaphylaxis.

  13. Development of a three component complex to increase isoniazid efficacy against isoniazid resistant and nonresistant Mycobacterium tuberculosis.

    PubMed

    Manning, Thomas; Plummer, Sydney; Baker, Tess; Wylie, Greg; Clingenpeel, Amy C; Phillips, Dennis

    2015-10-15

    The bacterium responsible for causing tuberculosis has evolved resistance to antibiotics used to treat the disease, resulting in new multidrug resistant Mycobacterium tuberculosis (MDR-TB) and extensively drug resistant M. tuberculosis (XDR-TB) strains. Analytical techniques (1)H and (13)C Nuclear Magnetic Resonance (NMR), Fourier Transform-Ion Cyclotron Resonance with Electrospray Ionization (FT-ICR/ESI), and Matrix Assisted Laser Desorption Ionization-Mass Spectrometry (MALDI-TOF-MS) were used to study different aspects of the Cu(II)-polyethylene glycol (PEG-3350)-sucrose-isoniazid and Cu(II)-polyethylene glycol (PEG3350)-glucose-isoniazid complexes. The Cu(II) cation, sucrose or glucose, and the aggregate formed by PEG primarily serve as a composite drug delivery agent for the frontline antibiotic, however the improvement in MIC values produced with the CU-PEG-SUC-INH complex suggest an additional effect. Several Cu-PEG-SUC-INH complex variations were tested against INH resistant and nonresistant strains of M. tuberculosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Anaphylaxis to Polyethylene Glycol (Colyte®) in a Patient with Diverticulitis

    PubMed Central

    2016-01-01

    Polyethylene glycols (PEGs) are believed to be chemically inert agents, but larger PEG polymers could have immunogenicity. A 39-year-old man was referred to emergency room for loss of consciousness and dyspnea after taking of PEG-3350 (Colyte®). In laboratory findings, the initial serum tryptase level was increased to 91.9 mg/L (normal range: 0.00-11.40 mg/L) without any other laboratory abnormalities. The intradermal test with 10 mg/mL Colyte® showed a 5 × 5 mm wheal, but basophil activation and histamine releasability tests were negative. PEG-3350 is widely used as an osmotic laxative due to its lack of absorption from the gastrointestinal tract. However, the loss of mucosal integrity at gastrointestinal membrane such as diverticulitis may be a predisposing factor for anaphylaxis to Colyte®. We report a case of anaphylaxis induced by the ingestion of PEG-3350 in a patient with diverticulitis which might be a risk factor of anaphylaxis. PMID:27550498

  15. Alkyne- and 1,6-elimination- succinimidyl carbonate - terminated heterobifunctional poly(ethylene glycol) for reversible "Click" PEGylation.

    PubMed

    Xie, Yumei; Duan, Shaofeng; Forrest, M Laird

    2010-01-01

    A new heterobifunctional (succinimidyl carbonate, SC)-activated poly(ethylene glycol) (PEG) with a reversible 1,6-elimination linker and a terminal alkyne for "click" chemistry was synthesized with high efficiency and low polydispersity. The α-alkyne-ω-hydroxyl PEG was first prepared using trimethylsilyl-2-propargyl alcohol as an initiator for ring-opening polymerization of ethylene oxide followed by mild deprotection with tetrabutylammonium fluoride. The hydroxy end was then modified with diglycolic anhydride to generate α-alkyne-ω-carboxylic acid PEG. The reversible 1, 6-elimination linker was introduced by conjugation of a hydroxymethyl phenol followed by activation with N,N'-disuccinimidyl carbonate to generate the heterobifunctional α-alkyne-ω-SC PEG. The terminal alkyne is available for "click" conjugation to azido ligands via 1,3-dipolar cycloaddition, and the succinimidyl carbonate will form a reversible conjugate to amines (e.g. in proteins) that can release the unaltered amine after base or enzyme catalyzed cleavage of the 1,6-linker.

  16. Temperature-Dependent Implicit-Solvent Model of Polyethylene Glycol in Aqueous Solution.

    PubMed

    Chudoba, Richard; Heyda, Jan; Dzubiella, Joachim

    2017-12-12

    A temperature (T)-dependent coarse-grained (CG) Hamiltonian of polyethylene glycol/oxide (PEG/PEO) in aqueous solution is reported to be used in implicit-solvent material models in a wide temperature (i.e., solvent quality) range. The T-dependent nonbonded CG interactions are derived from a combined "bottom-up" and "top-down" approach. The pair potentials calculated from atomistic replica-exchange molecular dynamics simulations in combination with the iterative Boltzmann inversion are postrefined by benchmarking to experimental data of the radius of gyration. For better handling and a fully continuous transferability in T-space, the pair potentials are conveniently truncated and mapped to an analytic formula with three structural parameters expressed as explicit continuous functions of T. It is then demonstrated that this model without further adjustments successfully reproduces other experimentally known key thermodynamic properties of semidilute PEG solutions such as the full equation of state (i.e., T-dependent osmotic pressure) for various chain lengths as well as their cloud point (or collapse) temperature.

  17. Certification and uncertainty evaluation of the certified reference materials of poly(ethylene glycol) for molecular mass fractions by using supercritical fluid chromatography.

    PubMed

    Takahashi, Kayori; Kishine, Kana; Matsuyama, Shigetomo; Saito, Takeshi; Kato, Haruhisa; Kinugasa, Shinichi

    2008-07-01

    Poly(ethylene glycol) (PEG) is a useful water-soluble polymer that has attracted considerable interest in medical and biological science applications as well as in polymer physics. Through the use of a well-calibrated evaporative light-scattering detector coupled with high performance supercritical fluid chromatography, we are able to determine exactly not only the average mass but also all of the molecular mass fractions of PEG samples needed for certified reference materials issued by the National Metrology Institute of Japan. In addition, experimental uncertainty was determined in accordance with the Guide to the expression of uncertainty in measurement (GUM). This reference material can be used to calibrate measuring instruments, to control measurement precision, and to confirm the validity of measurement methods when determining molecular mass distributions and average molecular masses. Especially, it is suitable for calibration against both masses and intensities for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

  18. Enhanced growth inhibition of prostate cancer in vitro and in vivo by a recombinant adenovirus-mediated dual-aptamer modified drug delivery system.

    PubMed

    Jing, Pei; Cao, Shousong; Xiao, Shuangli; Zhang, Xiaoqin; Ke, Siyun; Ke, Famin; Yu, Xin; Wang, Li; Wang, Shurong; Luo, Yuling; Zhong, Zhirong

    2016-12-28

    The peptide aptamer DUP-1 targets prostate-specific membrane antigen (PSMA)-negative cells, while the RNA aptamer A10-3.2 targets PSMA-positive prostate cancer cells. Moreover, the tumor-suppressor gene phosphatase and tensin homolog (PTEN) and the chemotherapeutic agent doxorubicin (DOX) effectively inhibit prostate cancer, and a recombinant adenovirus (Ad5) mediates high gene transfer efficiency. Here, we design a dual-aptamer modified tumor targeting gene and DOX delivery system mediated by recombinant adenovirus (A10-3.2(DOX)/DUP-1-PEG-Ad5, ADDP-Ad5). DUP-1 and A10-3.2 are connected to the adenovirus through polyethylene glycol (PEG), PTEN is integrated into Ad5, and DOX is embedded into the double chain of aptamer A10-3.2. The PEG-modification rate of Ad5 is 98.70 ± 2.43%. The DUP-1 and A10-3.2 modified products yield 80.40 ± 1.36% and 82.20 ± 2.14%, respectively. The uptake of ADDP-Ad5 and the expression of the reporter gene are enhanced by the system in PSMA-positive LNCaP and PSMA-negative PC3 human prostate cancer cells. ADDP-Ad5 significantly inhibits the cell growth of both LNCaP and PC3 cells. More importantly, ADDP-Ad5 is active in vivo against LNCaP and PC3 tumor xenografts and exhibits no significant toxicity to the mice. Therefore, ADDP-Ad5 may have clinical potential in prostate cancer therapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Changes in in vitro ruminal and post-ruminal degradation of tropical tannin-rich legumes due to varying levels of polyethylene glycol.

    PubMed

    Knowles, M M; Pabón, M L; Hess, H D; Carulla, J E

    2017-08-01

    We evaluated the effects of tannins from Flemingia macrophylla (CIAT 17403) and Calliandra calothyrsus (San Ramón CIAT 22310 and Patulul CIAT 22316) on in vitro ruminal and post-ruminal dry matter and apparent protein degradation. For each tannin source (legumes), different dosages of polyethylene glycol (PEG) (8000 Da) in McDougall buffer were added to achieve ratios of 0:3, 1:3, 2:3 and 3:3 PEG:condensed tannin (CT). Ruminal fluid mixed with McDougall buffer (1:4) was added to tubes containing only legume foliage (control) or PEG-treated legume foliage. For both Calliandra varieties, a higher ruminal dry matter degradation was observed at a PEG:CT ratio of 3:3. For F. macrophylla, no differences were found between 2:3 and 3:3 ratios (p > 0.05), indicating that a PEG:CT ratio of 2:3 might be enough to bind tannins. Increasing PEG:CT ratios increased apparent ruminal degraded protein and ammonia concentration (p < 0.0001) differing among species (species × ratio: p < 0.0001). The degradation of bypass crude protein (dBCP) was influenced by both legume type and PEG:CT ratio (p < 0.0001). For Patulul, as PEG:CT ratio increased, dBCP increased, but after tannin ratio of 2:3, there was not a significant increase, and for San Ramón, dBCP degradation was higher as PEG:CT ratio increased up to 2:3. For Flemingia, dBCP was higher than PEG:CT ratio of 0:3 but not different among 1:3, 2:3 or 3:3. Low concentration of CT (116 mg/g DM) increased the proportion of protein digested in the abomasum, but higher levels of CT (252 mg/g) clearly reduced the proportion of digested CP. For Flemingia, PEG:CT ratio of 2:3 is enough to inactivate tannins, while PEG:CT ratio of 3:3 was needed for Calliandra and consequently increased ruminal degradation of dry mater (rdDM), and crude protein (rdCP), total degradation of dry matter (tdDM), crude protein (tdCP) and ammonia levels. Journal of Animal Physiology and Animal Nutrition © 2017 Blackwell Verlag GmbH.

  20. Conjugation of cell-penetrating peptides with poly(lactic-co-glycolic acid)-polyethylene glycol nanoparticles improves ocular drug delivery

    PubMed Central

    Vasconcelos, Aimee; Vega, Estefania; Pérez, Yolanda; Gómara, María J; García, María Luisa; Haro, Isabel

    2015-01-01

    In this work, a peptide for ocular delivery (POD) and human immunodeficiency virus transactivator were conjugated with biodegradable poly(lactic-co-glycolic acid) (PGLA)–polyethylene glycol (PEG)-nanoparticles (NPs) in an attempt to improve ocular drug bioavailability. The NPs were prepared by the solvent displacement method following two different pathways. One involved preparation of PLGA NPs followed by PEG and peptide conjugation (PLGA-NPs-PEG-peptide); the other involved self-assembly of PLGA-PEG and the PLGA-PEG-peptide copolymer followed by NP formulation. The conjugation of the PEG and the peptide was confirmed by a colorimetric test and proton nuclear magnetic resonance spectroscopy. Flurbiprofen was used as an example of an anti-inflammatory drug. The physicochemical properties of the resulting NPs (morphology, in vitro release, cell viability, and ocular tolerance) were studied. In vivo anti-inflammatory efficacy was assessed in rabbit eyes after topical instillation of sodium arachidonate. Of the formulations developed, the PLGA-PEG-POD NPs were the smaller particles and exhibited greater entrapment efficiency and more sustained release. The positive charge on the surface of these NPs, due to the conjugation with the positively charged peptide, facilitated penetration into the corneal epithelium, resulting in more effective prevention of ocular inflammation. The in vitro toxicity of the NPs developed was very low; no ocular irritation in vitro (hen’s egg test–chorioallantoic membrane assay) or in vivo (Draize test) was detected. Taken together, these data demonstrate that PLGA-PEG-POD NPs are promising vehicles for ocular drug delivery. PMID:25670897

  1. SN-38 loaded polymeric micelles to enhance cancer therapy

    NASA Astrophysics Data System (ADS)

    Gu, Quanrong; Xing, James Z.; Huang, Min; He, Chuan; Chen, Jie

    2012-05-01

    7-Ethyl-10-hydroxycamptothecin (SN-38) loaded poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (Pluronic F-108) and poly(ethylene glycol)-block-poly(ɛ-caprolactone) (PEG-b-PCL) nanoparticles were successfully prepared by a modified film hydration method and characterized by scanning electric microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and dynamic light scattering (DLS). Satisfactory drug loading of 20.73 ± 0.66% and a high encapsulation efficiency of 83.83 ± 1.32% were achieved. The SN-38 nanoparticles (SN-38 NPs) can completely disperse into a phosphate buffered saline (PBS) medium to produce a clear aqueous suspension that remains stable for up to three days. Total drug releases were 67.91% and 91.09% after 24 h in a PBS or fetal bovine serum (FBS) medium. Half maximal inhibitory concentration (IC50) tests of SN-38 and SN-38 NPs on A549 lung cells produced results of 200.0 ± 14.9 ng ml-1 and 80.0 ± 4.6 ng ml-1, respectively. Similarly, IC50 tests of SN-38 and SN-38 NPs on MCF-7 breast cells yielded results of 16.0 ± 0.7 ng ml-1 and 8.0 ± 0.5 ng ml-1, respectively. These in vitro IC50 studies show significant (p < 0.01) enhancement of the SN-38 NP drug efficiency in killing cancer cells in comparison to the free drug SN-38 control. All the materials used for this nanoformulation are approved by the US FDA, with the virtue of extremely low toxicity to normal cells.

  2. Long residence time of ultrasound microbubbles targeted to integrin in murine tumor model.

    PubMed

    Jun, Hong Young; Park, Seong Hoon; Kim, Hun Soo; Yoon, Kwon-Ha

    2010-01-01

    The aim of this study was to evaluate the intratumoral residence time of microbubbles (MBs) targeted to alpha(v)beta(3) integrin expressed in the endothelial cells of mice during the process of tumor angiogenesis. For the preparation of MBs, decafluorobutane gas was sonically dispersed in phosphate buffer saline containing L-A-phosphatidylcholine-distearoyl, polyethylene glycol 40 stearate, and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[biotinyl(polyethylene glycol)2000] in a 77:15:8 molar ratio. Avidin-fluorescein isothiocyanate and biotin-cyclic arginine-glycine-aspartate-D-tyrosine-lysine (cRGD) or biotin-alanine-glycine-aspartate (AGD) conjugates were added to the reaction mixture. Adhesion testing of the targeting MBs was performed for the MS-1 cell line expressing alpha(v)beta(3) integrin in vitro. The in vivo acoustic properties of the MBs were assessed by clinical ultrasound on the HT1080 fibrosarcoma model (n = 8) for 1 hour. Cryosections were stained with hematoxylin and eosin and by immunohistochemical staining to identify expression of alpha(v)beta(3) integrin in the HT1080 tumor. The adherence of the MBs conjugated to cRGD was significantly greater than the adherence of the MBs conjugated to biotin-AGD (P < .01) for the MS-1 endothelial cell line. The acoustic enhancement on ultrasound was observed as a stable imaging window until 1 hour after injection of the MB conjugates in the mice. The MBs targeted via cRGD preferentially adhered to the vascular endothelium of the HT-1080 tumors. The findings of ultrasound imaging were correlated with immunohistochemical findings for the expression of alpha(v)beta(3) integrin on the vascular endothelium of the tumors. The prepared MBs conjugated with cRGD demonstrated a sufficient residence time to attach to the target integrin of tumor tissues. This finding suggests that the MBs are a potential molecular contrast agent that enables characterization of tumor angiogenesis and the monitoring of antitumor and antiangiogenic therapy.

  3. pH-Responsive Shape Memory Poly(ethylene glycol)-Poly(ε-caprolactone)-based Polyurethane/Cellulose Nanocrystals Nanocomposite.

    PubMed

    Li, Ying; Chen, Hongmei; Liu, Dian; Wang, Wenxi; Liu, Ye; Zhou, Shaobing

    2015-06-17

    In this study, we developed a pH-responsive shape-memory polymer nanocomposite by blending poly(ethylene glycol)-poly(ε-caprolactone)-based polyurethane (PECU) with functionalized cellulose nanocrystals (CNCs). CNCs were functionalized with pyridine moieties (CNC-C6H4NO2) through hydroxyl substitution of CNCs with pyridine-4-carbonyl chloride and with carboxyl groups (CNC-CO2H) via 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) mediated surface oxidation, respectively. At a high pH value, the CNC-C6H4NO2 had attractive interactions from the hydrogen bonding between pyridine groups and hydroxyl moieties; at a low pH value, the interactions reduced or disappeared due to the protonation of pyridine groups, which are a Lewis base. The CNC-CO2H responded to pH variation in an opposite manner. The hydrogen bonding interactions of both CNC-C6H4NO2 and CNC-CO2H can be readily disassociated by altering pH values, endowing the pH-responsiveness of CNCs. When these functionalized CNCs were added in PECU polymer matrix to form nanocomposite network which was confirmed with rheological measurements, the mechanical properties of PECU were not only obviously improved but also the pH-responsiveness of CNCs could be transferred to the nanocomposite network. The pH-sensitive CNC percolation network in polymer matrix served as the switch units of shape-memory polymers (SMPs). Furthermore, the modified CNC percolation network and polymer molecular chains also had strong hydrogen bonding interactions among hydroxyl, carboxyl, pyridine moieties, and isocyanate groups, which could be formed or destroyed through changing pH value. The shape memory function of the nanocomposite network was only dependent on the pH variation of the environment. Therefore, this pH-responsive shape-memory nancomposite could be potentially developed into a new smart polymer material.

  4. Degradation of bisphenol-A by dielectric barrier discharge system: influence of polyethylene glycol stabilized nano zero valent iron particles

    NASA Astrophysics Data System (ADS)

    Tijani, Jimoh O.; Mouele, Massima E. S.; Fatoba, Ojo O.; Babajide, Omotola O.; Petrik, Leslie F.

    2017-09-01

    In this study we report the synthesis and catalytic properties of polyethylene glycol stabilized nano zero valent iron particles (PEG-nZVI) added to the dielectric barrier discharge (DBD) system to induce photo-Fenton process in the degradation of bisphenol A (BPA) in aqueous solution. The influence of operating parameters such as solution pH, initial concentration of the modelled pollutant and PEG-nZVI dosage on the extent of BPA degradation was investigated. The residual concentration of BPA and its intermediates were determined using high performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LCMS). The high resolution scanning electron microscope (HRSEM), x-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) surface area, and x-ray photoelectron spectroscopy (XPS) analysis confirmed the formation of filamentous, high surface area iron nanoparticles in the zero valent state. The BPA mineralization rate was monitored using total organic carbon (TOC) analyser. 100% BPA removal was achieved with DBD/PEG-nZVI system within 30 min compared to 67.9% (BPA) with DBD alone after 80 min. The complete BPA removal within a short reaction time was attributed to the existence of a synergetic effect in the combined DBD/PEG-nZVI system. Five new transformation products of BPA namely: 4-nitrophenol (C6H5NO3), 4-nitrosophenolate (C6H4NO2), 4-(prop-1-en-2-yl) cyclohexa-3,5-diene-1,2-dione, (C9H8O2), 4-(2-hydroxylpropan-2-yl)cyclohexane-3,5-diene-1,2-dione (C9H10O3), and 1,2-dimethyl-4-(2-nitropropan-2-yl)benzene (C9H10NO4) were identified. BPA degradation proceeded via ozonation, hydroxylation, dimerization, and decarboxylation and nitration step. The combined DBD/photo-Fenton-induced process was found to be the most efficient in the elimination of BPA in aqueous solutions and DBD alone.

  5. [PREPARATION AND BIOCOMPATIBILITY OF IN SITU CROSSLINKING HYALURONIC ACID HYDROGEL].

    PubMed

    Liang, Jiabi; Li, Jun; Wang, Ting; Liang, Yuhong; Zou, Xuenong; Zhou, Guangqian; Zhou, Zhiyu

    2016-06-08

    To fabricate in situ crosslinking hyaluronic acid hydrogel and evaluate its biocompatibility in vitro. The acrylic acid chloride and polyethylene glycol were added to prepare crosslinking agent polyethylene glycol acrylate (PEGDA), and the molecular structure of PEGDA was analyzed by Flourier transformation infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy. Hyaluronic acid hydrogel was chemically modified to prepare hyaluronic acid thiolation (HA-SH). And the degree of HA-SH was analyzed qualitatively and quantitatively by Ellman method. HA-SH solution in concentrations ( W/V ) of 0.5%, 1.0%, and 1.5% and PEGDA solution in concentrations ( W/V ) of 2%, 4%, and 6% were prepared with PBS. The two solutions were mixed in different ratios, and in situ crosslinking hyaluronic acid hydrogel was obtained; the crosslinking time was recorded. The cellular toxicity of in situ crosslinking hyaluronic acid hydrogel (1.5% HA-SH and 4% PEGDA mixed) was tested by L929 cells. Meanwhile, the biocompatibility of hydrogel was tested by co-cultured with human bone mesenchymal stem cells (hBMSCs). Flourier transformation infrared spectroscopy showed that most hydroxyl groups were replaced by acrylate groups; 1H nuclear magnetic resonance spectroscopy showed 3 characteristic peaks of hydrogen representing acrylate and olefinic bond at 5-7 ppm. The thiolation yield of HA-SH was 65.4%. In situ crosslinking time of hyaluronic acid hydrogel was 2 to 70 minutes in the PEGDA concentrations of 2%-6% and HA-SH concentrations of 0.5%-1.5%. The hyaluronic acid hydrogel appeared to be transparent. The toxicity grade of leaching solution of hydrogel was grade 1. hBMSCs grew well and distributed evenly in hydrogel with a very high viability. In situ crosslinking hyaluronic acid hydrogel has low cytotoxicity, good biocompatibility, and controllable crosslinking time, so it could be used as a potential tissue engineered scaffold or repairing material for tissue regeneration.

  6. European Science Notes Information Bulletin Reports on Current European/Middle Eastern Science,

    DTIC Science & Technology

    1988-02-01

    monosaccharides and stated that genetic stability of certain for the preparation of isotopically la- recombinant microoraanisms is one of the beled sugars...hydrocarbons and polyethylene glycol (PEG)/ polysaccharide hydrocarbon derivatives) in the aqueous and PEG/salt. The polysaccharide may be phase. The solvent

  7. Ligand adsorption and exchange on pegylated gold nanoparticles

    USDA-ARS?s Scientific Manuscript database

    Previous researchers proposed that thiolated poly(ethylene glycol) (PEG-SH) adopts a “mushroom-like” conformation on gold nanoparticles (AuNPs) in water. However, information regarding the size and permeability of the PEG-SH mushroom caps and surface area passivated by the PEG-SH mushroom stems are ...

  8. Greener iodination of arenes using sulphated ceria-zirconia catalysts in polyethylene glycol

    EPA Science Inventory

    An environmentally benign method for the selective monoiodination of diverse aromatic compounds has been developed using reusable sulphated ceria-zirconia under mild conditions. The protocol provides moderate to good yields of aryl iodides in PEG-200 as a greener solvent. The cat...

  9. Use of amphiphilic triblock copolymers for enhancing removal efficiency of organic pollutant from contaminated media

    NASA Astrophysics Data System (ADS)

    Lee, Jun Hyup; Lee, Byungsun; Son, Intae; Kim, Jae Hong; Kim, Chunho; Yoo, Ji Yong; Wu, Jong-Pyo; Kim, Younguk

    2015-11-01

    We have studied amphiphilic triblock copolymers poly(ethylene glycol)- b-poly(propylene glycol)- b-poly(ethylene glycol) (PEG- b-PPG- b-PEG) and poly(propylene glycol)- b-poly(ethylene glycol)- b-poly(propylene glycol) (PPG- b-PEG- b-PPG) as possible substitutes for sodium dodecyl sulfate as anionic surfactants for the removal of hydrophobic contaminants. The triblock copolymers were compared with sodium dodecyl sulfate in terms of their abilities to remove toluene as hydrophobic contaminant in fuel, and the effects of polymer structure, PEG content, and concentration were studied. The PEG- b-PPG- b-PEG copolymer containing two hydrophilic PEG blocks was more effective for the removal of hydrophobic contaminant at extremely high concentration. We also measured the removal capabilities of the triblock copolymers having various PEG contents and confirmed that removal capability was greatest at 10% PEG content regardless of polymer structure. As with sodium dodecyl sulfate, the removal efficiency of a copolymer has a positive correlation with its concentration. Finally, we proposed the amphiphilic triblock copolymer of PPG- b-PEG- b-PPG bearing 10% PEG content that proved to be the most effective substitute for sodium dodecyl sulfate.

  10. A simple and facile Heck-type arylation of alkenes with diaryliodonium salts using magnetically recoverable Pd-catalyst

    EPA Science Inventory

    The Heck-type arylation of alkenes was achieved in aqueous polyethylene glycol using a magnetically recoverable heterogenized palladium catalyst employing diaryliodonium salts under ambient conditions. The benign reaction medium and the stability of the catalyst are the salient f...

  11. Hydrogels Prepared from Cross-Linked Nanofibrillated Cellulose

    Treesearch

    Sandeep S. Nair; J.Y. Zhu; Yulin Deng; Arthur J. Ragauskas

    2014-01-01

    Nanocomposite hydrogels were developed by cross-linking nanofibrillated cellulose with poly(methyl vinyl ether-co-maleic acid) and polyethylene glycol. The cross-linked hydrogels showed enhanced water absorption and gel content with the addition of nanocellulose. In addition, the thermal stability, mechanical strength, and modulus increased with an increase in the...

  12. 40 CFR 721.3900 - Alkyl polyethylene glycol phosphate, potassium salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... methods for protecting against such risk, into a Material Safety Data Sheet (MSDS) as described in § 721..., potassium salt. 721.3900 Section 721.3900 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... or method of manufacture, import, or processing associated with any use of this substance without...

  13. Green Fluorescent Protein (GFP) as a reporter gene for the plant pathogenic oomycete Phytophthora ramorum

    Treesearch

    Marko Riedel; Gautier Calmin; Lassaad Belbahri; Francois Lefort; Monika Gotz; Stefan Wagner; Sabine Werres

    2009-01-01

    Transgenic Phytophthora ramorum strains that produce green fluorescent protein (GFP) constitutively were obtained after stable DNA integration using a polyethylene glycol and CaCl2-based transformation protocol. Green fluorescent protein production was studied in developing colonies and in different propagules of the pathogen...

  14. 76 FR 70896 - Polyethylene Glycol; Tolerance Exemption

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-16

    ... a finite tolerance is not necessary to ensure that there is a reasonable certainty that no harm will... integral part of its composition the atomic elements carbon, hydrogen, and oxygen. 3. The polymer does not contain as an integral part of its composition, except as impurities, any element other than those listed...

  15. 76 FR 51037 - Determination That Halflytely and Bisacodyl Tablets Bowel Prep Kit (Containing Two Bisacodyl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-17

    ... determined that Halflytely and Bisacodyl Tablets Bowel Prep Kit (polyethylene glycol (PEG) 3350, sodium chloride, sodium bicarbonate, and potassium chloride for oral solution and two bisacodyl delayed release... kits containing PEG-3350, sodium chloride, sodium bicarbonate, and potassium chloride for oral solution...

  16. 75 FR 13292 - Determination That HalfLytely and Bisacodyl Tablets Bowel Prep Kit (Containing 4 Bisacodyl...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-19

    ... determined that HALFLYTELY AND BISACODYL TABLETS BOWEL PREP KIT (polyethylene glycol (PEG) 3350, sodium chloride, sodium bicarbonate, and potassium chloride for oral solution and 4 bisacodyl delayed release... kits containing PEG-3350, sodium chloride, sodium bicarbonate, and potassium chloride for oral solution...

  17. Medical Management of Constipation

    PubMed Central

    Portalatin, Meredith; Winstead, Nathaniel

    2012-01-01

    Constipation is a common clinical problem. Initial management of chronic constipation should include lifestyle maneuvers, and increased fiber and fluids. Polyethylene glycol, sodium picosulfate, bisacodyl, prucalopride, lubiprostone, and linaclotide were all more effective than placebo for treating chronic idiopathic constipation. Many commonly used agents lack quality evidence supporting their use. PMID:23449608

  18. Poly(ethylene glycol) stabilized Co nanoparticles as highly active and selective catalysts for the Pauson-Khand reaction.

    PubMed

    Muller, Jean-Luc; Klankermayer, Jürgen; Leitner, Walter

    2007-05-21

    PEG-stabilized cobalt nanoparticles were prepared by thermal decomoposition of [Co2(CO)8] in PEG and were shown to be highly active and selective catalysts, for intra- and intermolecular Pauson-Khand reactions (PKR), in organic solvents or aqueous media.

  19. Copper-catalyzed Green and Expeditious N-Arylation of Sulfoximines using Diaryliodonium Salts

    EPA Science Inventory

    An ultrasound-accelerated green route for an expeditious N-arylation of NH-sulfoximines is described that involves the use of benign diaryliodonium salts in aqueous polyethylene glycol-400 and copper(I) bromide as catalyst at room temperature. The high yields of the products and...

  20. 21 CFR 177.2800 - Textiles and textile fibers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... ethyl sulfate For use only as a lubricant in the manufacture of polyethylene terephthalate fibers...-octadecenamido)ethyl-2-imidazolinium ethyl sulfate. Hexylene glycol (2-methyl,-2,4-pentanediol) Isobutyl alcohol Isopropyl alcohol Kerosene Methyl ester of sulfated ricebran oil Mineral oil For use only at a level not to...

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