A positive chemical ionization GC/MS method for the determination of airborne ethylene glycol and propylene glycols in non-occupational environments.

PubMed

Zhu, Jiping; Feng, Yong-Lai; Aikawa, Bio

2004-11-01

An analytical method for ethylene glycol and propylene glycols has been developed for measuring airborne levels of these chemicals in non-occupational environments such as residences and office buildings. The analytes were collected on charcoal tubes, solvent extracted, and analyzed by gas chromatography-mass spectrometry using a positive chemical ionization technique. The method had a method detection limit of 0.07 microg m(-3) for ethylene glycol and 0.03 microg m(-3) for 1,2- and 1,3-propylene glycols, respectively, based on a 1.44 m3 sampling volume. Indoor air samples of several residential homes and other indoor environments have been analyzed. The median concentrations of ethylene glycol and 1,2-propylene glycol in nine residential indoor air samples were 53 microg m(-3) and 13 microg m(-3) respectively with maximum values of 223 microg m(-3) and 25 microg m(-3) detected for ethylene glycol and 1,2-propylene glycol respectively. The concentrations of these two chemicals in one office and two laboratories were at low microg m(-3) levels. The maximum concentration of 1,3-propylene glycol detected in indoor air was 0.1 microg m(-3).

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

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

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.

Preparation, characterization and pharmacokinetics of fluorescence labeled propylene glycol alginate sodium sulfate

NASA Astrophysics Data System (ADS)

Li, Pengli; Li, Chunxia; Xue, Yiting; Zhang, Yang; Liu, Hongbing; Zhao, Xia; Yu, Guangli; Guan, Huashi

2014-08-01

A rapid and sensitive fluorescence labeling method was developed and validated for the microanalysis of a sulfated polysaccharide drug,namely propylene glycol alginate sodium sulfate (PSS), in rat plasma. Fluorescein isothiocyanate (FITC) was selected to label PSS, and 1, 6-diaminohexane was used to link PSS and FITC in order to prepare FITC-labeled PSS (F-PSS) through a reductive amination reaction. F-PSS was identified by UV-Vis, FT-IR and 1H-NMR spectrum. The cell stability and cytotoxicity of F-PSS were tested in Madin-Darby canine kidney (MDCK) cells. The results indicated that the labeling efficiency of F-PSS was 0.522% ± 0.0248% and the absolute bioavailability was 8.39%. F-PSS was stable in MDCK cells without obvious cytotoxicity. The method was sensitive and reliable; it showed a good linearity, precision, recovery and stability. The FITC labeling method can be applied to investigating the absorption and metabolism of PSS and other polysaccharides in biological samples.

Interim glycol flowsheet reduction/oxidation (redox) model for the Defense Waste Processing Facility (DWPF)

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

Jantzen, C. M.; Williams, M. S.; Zamecnik, J. R.

Control of the REDuction/OXidation (REDOX) state of glasses containing high concentrations of transition metals, such as High Level Waste (HLW) glasses, is critical in order to eliminate processing difficulties caused by overly reduced or overly oxidized melts. Operation of a HLW melter at Fe +2/ΣFe ratios of between 0.09 and 0.33, a range which is not overly oxidizing or overly reducing, helps retain radionuclides in the melt, i.e. long-lived radioactive 99Tc species in the less volatile reduced Tc 4+ state, 104Ru in the melt as reduced Ru +4 state as insoluble RuO 2, and hazardous volatile Cr 6+ in themore » less soluble and less volatile Cr +3 state in the glass. The melter REDOX control balances the oxidants and reductants from the feed and from processing additives such as antifoam. Currently, the Defense Waste Processing Facility (DWPF) is running a formic acid-nitric acid (FN) flowsheet where formic acid is the main reductant and nitric acid is the main oxidant. During decomposition formate and formic acid releases H 2 gas which requires close control of the melter vapor space flammability. A switch to a nitric acid-glycolic acid (GN) flowsheet is desired as the glycolic acid flowsheet releases considerably less H 2 gas upon decomposition. This would greatly simplify DWPF processing. Development of an EE term for glycolic acid in the GN flowsheet is documented in this study.« less

Process for the production of low flammability electrolyte solvents

DOEpatents

Krumdick, Gregory K.; Pupek, Krzysztof; Dzwiniel, Trevor L.

2016-02-16

The invention provides a method for producing electrolyte solvent, the method comprising reacting a glycol with a disilazane in the presence of a catalyst for a time and at a temperature to silylate the glycol, separating the catalyst from the silylated glycol, removing unreacted silazane; and purifying the silylated glycol.

Preparation of the vulcan XC-72R-supported Pt nanoparticles for the hydrogen evolution reaction in PEM water electrolysers

NASA Astrophysics Data System (ADS)

Du Nguyen, Huy; Thuy Luyen Nguyen, T.; Nguyen, Khac Manh; Ha, Thuc Huy; Hien Nguyen, Quoc

2015-01-01

Pt nanoparticles on vulcan XC-72R support (Pt/vulcan XC-72R) were prepared by the impregnation-reduction method. The Pt content, the morphological properties and the electrochemical catalysis of the Pt/vulcan XC 72R materials have been investigated by ICP-OES analysis, FESEM, TEM, and cyclic voltammetry. These materials were then used as catalyst for hydrogen evolution reaction at the cathode of proton exchange membrane (PEM) water electrolysers. The best catalyst was Pt/vulcan XC-72R prepared by the impregnation-reduction method which is conducted in two reducing steps with the reductants of sodium borohydride and ethylene glycol, respectively. The current density of PEM water electrolysers reached 1.0 A cm-2 when applying a voltage of 2.0 V at 25 °C.

CO2-Free Power Generation on an Iron Group Nanoalloy Catalyst via Selective Oxidation of Ethylene Glycol to Oxalic Acid in Alkaline Media

PubMed Central

Matsumoto, Takeshi; Sadakiyo, Masaaki; Ooi, Mei Lee; Kitano, Sho; Yamamoto, Tomokazu; Matsumura, Syo; Kato, Kenichi; Takeguchi, Tatsuya; Yamauchi, Miho

2014-01-01

An Fe group ternary nanoalloy (NA) catalyst enabled selective electrocatalysis towards CO2-free power generation from highly deliverable ethylene glycol (EG). A solid-solution-type FeCoNi NA catalyst supported on carbon was prepared by a two-step reduction method. High-resolution electron microscopy techniques identified atomic-level mixing of constituent elements in the nanoalloy. We examined the distribution of oxidised species, including CO2, produced on the FeCoNi nanoalloy catalyst in the EG electrooxidation under alkaline conditions. The FeCoNi nanoalloy catalyst exhibited the highest selectivities toward the formation of C2 products and to oxalic acid, i.e., 99 and 60%, respectively, at 0.4 V vs. the reversible hydrogen electrode (RHE), without CO2 generation. We successfully generated power by a direct EG alkaline fuel cell employing the FeCoNi nanoalloy catalyst and a solid-oxide electrolyte with oxygen reduction ability, i.e., a completely precious-metal-free system. PMID:25004118

Corrosion impact of reductant on DWPF and downstream facilities

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

Mickalonis, J. I.; Imrich, K. J.; Jantzen, C. M.

2014-12-01

Glycolic acid is being evaluated as an alternate reductant in the preparation of high level waste for the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS). During processing, the glycolic acid is not completely consumed and small quantities of the glycolate anion are carried forward to other high level waste (HLW) facilities. The impact of the glycolate anion on the corrosion of the materials of construction throughout the waste processing system has not been previously evaluated. A literature review had revealed that corrosion data in glycolate-bearing solution applicable to SRS systems were not available. Therefore, testing wasmore » recommended to evaluate the materials of construction of vessels, piping and components within DWPF and downstream facilities. The testing, conducted in non-radioactive simulants, consisted of both accelerated tests (electrochemical and hot-wall) with coupons in laboratory vessels and prototypical tests with coupons immersed in scale-up and mock-up test systems. Eight waste or process streams were identified in which the glycolate anion might impact the performance of the materials of construction. These streams were 70% glycolic acid (DWPF feed vessels and piping), SRAT/SME supernate (Chemical Processing Cell (CPC) vessels and piping), DWPF acidic recycle (DWPF condenser and recycle tanks and piping), basic concentrated recycle (HLW tanks, evaporators, and transfer lines), salt processing (ARP, MCU, and Saltstone tanks and piping), boric acid (MCU separators), and dilute waste (HLW evaporator condensate tanks and transfer line and ETF components). For each stream, high temperature limits and worst-case glycolate concentrations were identified for performing the recommended tests. Test solution chemistries were generally based on analytical results of actual waste samples taken from the various process facilities or of prototypical simulants produced in the laboratory. The materials of construction for most vessels, components and piping were not impacted with the presence of glycolic acid or the impact is not expected to affect the service life. However, the presence of the glycolate anion was found to affect corrosion susceptibility of some materials of construction in the DWPF and downstream facilities, especially at elevated temperatures. The following table summarizes the results of the electrochemical and hot wall testing and indicates expected performance in service with the glycolate anion present.« less

Enhanced Catalytic Activities of NiPt Truncated Octahedral Nanoparticles toward Ethylene Glycol Oxidation and Oxygen Reduction in Alkaline Electrolyte.

PubMed

Xia, Tianyu; Liu, Jialong; Wang, Shouguo; Wang, Chao; Sun, Young; Gu, Lin; Wang, Rongming

2016-05-04

The high cost and poor durability of Pt nanoparticles (NPs) are great limits for the proton exchange membrane fuel cells (PEMFCs) from being scaled-up for commercial applications. Pt-based bimetallic NPs together with a uniform distribution can effectively reduce the usage of expensive Pt while increasing poison resistance of intermediates. In this work, a simple one-pot method was used to successfully synthesize ultrafine (about 7.5 nm) uniform NiPt truncated octahedral nanoparticles (TONPs) in dimethylformamid (DMF) without any seeds or templates. The as-prepared NiPt TONPs with Pt-rich surfaces exhibit greatly improved catalytic activities together with good tolerance and better stability for ethylene glycol oxidation reaction (EGOR) and oxygen reduction reaction (ORR) in comparison with NiPt NPs and commercial Pt/C catalysts in alkaline electrolyte. For example, the value of mass and specific activities for EGOR are 23.2 and 17.6 times higher comparing with those of commercial Pt/C, respectively. Our results demonstrate that the dramatic enhancement is mainly attributed to Pt-rich surface, larger specific surface area, together with coupling between Ni and Pt atoms. This developed method provides a promising pathway for simple preparation of highly efficient electrocatalysts for PEMFCs in the near future.

A Fast, Accurate and Sensitive GC-FID Method for the Analyses of Glycols in Water and Urine

NASA Technical Reports Server (NTRS)

Kuo, C. Mike; Alverson, James T.; Gazda, Daniel B.

2017-01-01

Glycols, specifically ethylene glycol and 1,2-propanediol, are some of the major organic compounds found in the humidity condensate samples collected on the International Space Station. The current analytical method for glycols is a GC/MS method with direct sample injection. This method is simple and fast, but it is not very sensitive. Reporting limits for ethylene glycol and 1,2-propanediol are only 1 ppm. A much more sensitive GC/FID method was developed, in which glycols were derivatized with benzoyl chloride for 10 minutes before being extracted with hexane. Using 1,3-propanediol as an internal standard, the detection limits for the GC/FID method was determined to be 50 ppb and the analysis only takes 7 minutes. Data from the GC/MS and the new GC/FID methods shows excellent agreement with each other. Factors affecting the sensitivity, including sample volume, NaOH concentration and volume, volume of benzoyl chloride, reaction time and temperature, were investigated. Interferences during derivatization and possible method to reduce interferences were also investigated.

Ligand exchange in ionic systems and its effect on silver nucleation and growth.

PubMed

Abbott, Andrew P; Azam, Muhammad; Frisch, Gero; Hartley, Jennifer; Ryder, Karl S; Saleem, Saima

2013-10-28

The electrodeposition of metals from ionic solutions is intrinsically linked to the reactivity of the solute ions. When metal salts dissolve, the exchange of the anion with the molecular and ionic components from solution affects the speciation and therefore the characteristics of metal reduction. This study investigates the nucleation mechanism, deposition kinetics, metal speciation and diffusion coefficients of silver salts dissolved in Deep Eutectic Solvents. The electrochemical reduction of AgCl, AgNO3 and Ag2O is studied in 1 : 2 choline chloride : ethylene glycol and 1 : 2 choline chloride : urea. Cyclic voltammetry is used to evaluate electrochemical kinetics. Detailed analysis of chronoamperometric data shows that silver deposits form via multiple 3D nucleation with mass transport controlled hemispherical growth. The nucleation mechanism was found to be potential dependent, varying from progressive to instantaneous as the reduction potential becomes more cathodic. Diffusion coefficients are determined using three different methods. Trends are rationalised in terms of solvent viscosity and silver speciation analysis with EXAFS. The morphology of electroreduced silver is investigated with scanning electron microscopy and shows that deposits from the urea based liquid form more dense morphologies than those from the ethylene glycol based liquid.

Preparation and Thermo-Physical Properties of Fe2O3-Propylene Glycol Nanofluids.

PubMed

Shylaja, A; Manikandan, S; Suganthi, K S; Rajan, K S

2015-02-01

Iron oxide (Fe2O3) nanoparticles were prepared from ferric chloride and ferrous sulphate by precipitation reaction. Fe2O3-propylene glycol nanofluid was prepared by dispersing Fe2O3 nanoparticles in propylene glycol through stirred bead milling, shear homogenization and probe ultrasonication. The nanofluid was characterized through measurement of viscosity, particle size distribution and thermal conductivity. The interactions between Fe2O3 nanoparticles and propylene glycol on the nanoparticle surfaces lead to reduction in viscosity, the magnitude of which increases with nanoparticle concentration (0-2 vol%) at room temperature. The thermal conductivity enhancement for 2 vol% nanofluid was about 21% at room temperature, with liquid layering being the major contributor for thermal conductivity enhancement.

Determination of glycols in air: development of sampling and analytical methodology and application to theatrical smokes.

PubMed

Pendergrass, S M

1999-01-01

Glycol-based fluids are used in the production of theatrical smokes in theaters, concerts, and other stage productions. The fluids are heated and dispersed in aerosol form to create the effect of a smoke, mist, or fog. There have been reports of adverse health effects such as respiratory irritation, chest tightness, shortness of breath, asthma, and skin rashes. Previous attempts to collect and quantify the aerosolized glycols used in fogging agents have been plagued by inconsistent results, both in the efficiency of collection and in the chromatographic analysis of the glycol components. The development of improved sampling and analytical methodology for aerosolized glycols was required to assess workplace exposures more effectively. An Occupational Safety and Health Administration versatile sampler tube was selected for the collection of ethylene glycol, propylene glycol, 1,3-butylene glycol, diethylene glycol, triethylene glycol, and tetraethylene glycol aerosols. Analytical methodology for the separation, identification, and quantitation of the six glycols using gas chromatography/flame ionization detection is described. Limits of detection of the glycol analytes ranged from 7 to 16 micrograms/sample. Desorption efficiencies for all glycol compounds were determined over the range of study and averaged greater than 90%. Storage stability results were acceptable after 28 days for all analytes except ethylene glycol, which was stable at ambient temperature for 14 days. Based on the results of this study, the new glycol method was published in the NIOSH Manual of Analytical Methods.

Development of novel purifiers with appropriate functional groups based on solvent polarities at bulk filtration

NASA Astrophysics Data System (ADS)

Kohyama, Tetsu; Kaneko, Fumiya; Ly, Saksatha; Hamzik, James; Jaber, Jad; Yamada, Yoshiaki

2017-03-01

Weak-polar solvents like PGMEA (Propylene Glycol Monomethyl Ether Acetate) or CHN (Cyclohexanone) are used to dissolve hydrophobic photo-resist polymers, which are challenging for traditional cleaning methods such as distillation, ion-exchange resins service or water-washing processes. This paper investigated two novel surface modifications to see their effectiveness at metal removal and to understand the mechanism. The experiments yielded effective purification methods for metal reduction, focusing on solvent polarities based on HSP (Hansen Solubility Parameters), and developing optimal purification strategies.

Alternate Reductant Cold Cap Evaluation Furnace Phase II Testing

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

Johnson, F. C.; Stone, M. E.; Miller, D. H.

2014-09-03

Savannah River Remediation (SRR) conducted a Systems Engineering Evaluation (SEE) to determine the optimum alternate reductant flowsheet for the Defense Waste Processing Facility (DWPF). Specifically, two proposed flowsheets (nitric–formic–glycolic and nitric–formic–sugar) were evaluated based upon results from preliminary testing. Comparison of the two flowsheets among evaluation criteria indicated a preference towards the nitric–formic–glycolic flowsheet. Further research and development of this flowsheet eliminated the formic acid, and as a result, the nitric–glycolic flowsheet was recommended for further testing. Based on the development of a roadmap for the nitric–glycolic acid flowsheet, Waste Solidification Engineering (WS-E) issued a Technical Task Request (TTR) tomore » address flammability issues that may impact the implementation of this flowsheet. Melter testing was requested in order to define the DWPF flammability envelope for the nitric-glycolic acid flowsheet. The Savannah River National Laboratory (SRNL) Cold Cap Evaluation Furnace (CEF), a 1/12 th scale DWPF melter, was selected by the SRR Alternate Reductant project team as the melter platform for this testing. The overall scope was divided into the following sub-tasks as discussed in the Task Technical and Quality Assurance Plan (TTQAP): Phase I - A nitric–formic acid flowsheet melter test (unbubbled) to baseline the CEF cold cap and vapor space data to the benchmark melter flammability models; Phase II - A nitric–glycolic acid flowsheet melter test (unbubbled and bubbled) to: Define new cold cap reactions and global kinetic parameters in support of the melter flammability model development; Quantify off-gas surging potential of the feed; Characterize off-gas condensate for complete organic and inorganic carbon species. After charging the CEF with cullet from Phase I CEF testing, the melter was slurry-fed with glycolic flowsheet based SB6-Frit 418 melter feed at 36% waste loading and was operated continuously for 25 days. Process data was collected throughout testing and included melter operation parameters and off-gas chemistry. In order to generate off-gas data in support of the flammability model development for the nitric-glycolic flowsheet, vapor space steady state testing in the range of ~300-750°C was conducted under the following conditions, (i) 100% (nominal and excess antifoam levels) and 125% stoichiometry feed and (ii) with and without argon bubbling. Adjustments to feed rate, heater outputs and purge air flow were necessary in order to achieve vapor space temperatures in this range. Surge testing was also completed under nominal conditions for four days with argon bubbling and one day without argon bubbling.« less

Methods of producing compounds from plant material

DOEpatents

Werpy, Todd A.; Schmidt, Andrew J.; Frye, Jr., John G.; Zacher, Alan H.; Franz, James A.; Alnajjar, Mikhail S.; Neuenschwander, Gary G.; Alderson, Eric V.; Orth, Rick J.; Abbas, Charles A.; Beery, Kyle E.; Rammelsberg, Anne M.; Kim, Catherine J.

2006-01-03

The invention includes methods of processing plant material by adding water to form a mixture, heating the mixture, and separating a liquid component from a solid-comprising component. At least one of the liquid component and the solid-comprising component undergoes additional processing. Processing of the solid-comprising component produces oils, and processing of the liquid component produces one or more of glycerol, ethylene glycol, lactic acid and propylene glycol. The invention includes a process of forming glycerol, ethylene glycol, lactic acid and propylene glycol from plant matter by adding water, heating and filtering the plant matter. The filtrate containing starch, starch fragments, hemicellulose and fragments of hemicellulose is treated to form linear poly-alcohols which are then cleaved to produce one or more of glycerol, ethylene glycol, lactic acid and propylene glycol. The invention also includes a method of producing free and/or complexed sterols and stanols from plant material.

Methods of producing compounds from plant materials

DOEpatents

Werpy, Todd A [West Richland, WA; Schmidt, Andrew J [Richland, WA; Frye, Jr., John G.; Zacher, Alan H. , Franz; James A. , Alnajjar; Mikhail S. , Neuenschwander; Gary G. , Alderson; Eric V. , Orth; Rick J. , Abbas; Charles A. , Beery; Kyle E. , Rammelsberg; Anne M. , Kim; Catherine, J [Decatur, IL

2010-01-26

The invention includes methods of processing plant material by adding water to form a mixture, heating the mixture, and separating a liquid component from a solid-comprising component. At least one of the liquid component and the solid-comprising component undergoes additional processing. Processing of the solid-comprising component produces oils, and processing of the liquid component produces one or more of glycerol, ethylene glycol, lactic acid and propylene glycol. The invention includes a process of forming glycerol, ethylene glycol, lactic acid and propylene glycol from plant matter by adding water, heating and filtering the plant matter. The filtrate containing starch, starch fragments, hemicellulose and fragments of hemicellulose is treated to form linear poly-alcohols which are then cleaved to produce one or more of glycerol, ethylene glycol, lactic acid and propylene glycol. The invention also includes a method of producing free and/or complexed sterols and stanols from plant material.

Fast determination of ethylene glycol, 1,2-propylene glycol and glycolic acid in blood serum and urine for emergency and clinical toxicology by GC-FID.

PubMed

Hložek, Tomáš; Bursová, Miroslava; Čabalaa, Radomír

2014-12-01

A simple, cost effective, and fast gas chromatography method with flame ionization detection (GC-FID) for simultaneous measurement of ethylene glycol, 1,2-propylene glycol and glycolic acid was developed and validated for clinical toxicology purposes. This new method employs a relatively less used class of derivatization agents - alkyl chloroformates, allowing the efficient and rapid derivatization of carboxylic acids within seconds while glycols are simultaneously derivatized by phenylboronic acid. The entire sample preparation procedure is completed within 10 min. To avoid possible interference from naturally occurring endogenous acids and quantitation errors 3-(4-chlorophenyl) propionic acid was chosen as an internal standard. The significant parameters of the derivatization have been found using chemometric procedures and these parameters were optimized using the face-centered central composite design. The calibration dependence of the method was proved to be quadratic in the range of 50-5000 mg mL(-1), with adequate accuracy (92.4-108.7%) and precision (9.4%). The method was successfully applied to quantify the selected compounds in serum of patients from emergency units. Copyright © 2014 Elsevier B.V. All rights reserved.

Hydrogen production through aqueous-phase reforming of ethylene glycol in a washcoated microchannel.

PubMed

D'Angelo, M Fernanda Neira; Ordomsky, Vitaly; Paunovic, Violeta; van der Schaaf, John; Schouten, Jaap C; Nijhuis, T Alexander

2013-09-01

Aqueous-phase reforming (APR) of biocarbohydrates is conducted in a catalytically stable washcoated microreactor where multiphase hydrogen removal enhances hydrogen efficiency. Single microchannel experiments are conducted following a simplified model based on the microreactor concept. A coating method to deposit a Pt-based catalyst on the microchannel walls is selected and optimized. APR reactivity tests are performed by using ethylene glycol as the model compound. Optimum results are achieved with a static washcoating technique; a highly uniform and well adhered 5 μm layer is deposited on the walls of a 320 μm internal diameter (ID) microchannel in one single step. During APR of ethylene glycol, the catalyst layer exhibits high stability over 10 days after limited initial deactivation. The microchannel presents higher conversion and selectivity to hydrogen than a fixed-bed reactor. The benefits of using a microreactor for APR can be further enhanced by utilizing increased Pt loadings, higher reaction temperatures, and larger carbohydrates (e.g., glucose). The use of microtechnology for aqueous-phase reforming will allow for a great reduction in the reformer size, thus rendering it promising for distributed hydrogen production. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synthesis of 3 alpha, 5 alpha-tetrahydroaldosterone.

PubMed

Harnik, M; Kashman, Y; Morris, D J

1984-06-01

3 alpha, 5 alpha-Tetrahydroaldosterone (12a), a metabolite of aldosterone, has been synthesized from the lactone 2a or, preferably 11 beta, 21-dihydroxy-5-pregnene-3,20-dione-18-oic acid 3,20-di-(ethylene glycol)-ketal (18----11) lactone 21-acetate (6b), via 11 beta, 21-dihydroxy-5 alpha-pregnane-3,20-dione-18-oic acid 3,20-di-(ethylene glycol) ketal (18----11) lactone 21-acetate (4b). Selective hydrolysis of the latter at C-3 furnished the monoketal 5 which, on reduction with potassium tri-sec-butylborohydride, yielded predominantly 3 alpha, 11 beta, 21-trihydroxy-5 alpha-pregnan-20-one-18-oic acid 20-(ethylene glycol)-ketal (18----11) lactone (8a) and its acetate 8b. Further reduction with diisobutylaluminum hydride afforded 3 alpha, 5 alpha-tetrahydroaldosterone-20-ketal (10a), which was directly hydrolyzed to 12a with dilute acid in tetrahydrofuran-dioxan. Periodate oxidation led to the gamma-etiolactone 14a, which was then further converted into 5 alpha-dihydroaldosterone-gamma-etiolactone (14c).

Corrosion Testing of Monofrax K-3 Refractory in Defense Waste Processing Facility (DWPF) Alternate Reductant Feeds

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

Williams, M.; Jantzen, C.; Burket, P.

The Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS) uses a combination of reductants and oxidants while converting high level waste (HLW) to a borosilicate waste form. A reducing flowsheet is maintained to retain radionuclides in their reduced oxidation states which promotes their incorporation into borosilicate glass. For the last 20 years of processing, the DWPF has used formic acid as the main reductant and nitric acid as the main oxidant. During reaction in the Chemical Process Cell (CPC), formate and formic acid release measurably significant H 2 gas which requires monitoring of certain vessel’s vapor spaces.more » A switch to a nitric acid-glycolic acid (NG) flowsheet from the nitric-formic (NF) flowsheet is desired as the NG flowsheet releases considerably less H 2 gas upon decomposition. This would greatly simplify DWPF processing from a safety standpoint as close monitoring of the H 2 gas concentration could become less critical. In terms of the waste glass melter vapor space flammability, the switch from the NF flowsheet to the NG flowsheet showed a reduction of H 2 gas production from the vitrification process as well. Due to the positive impact of the switch to glycolic acid determined on the flammability issues, evaluation of the other impacts of glycolic acid on the facility must be examined.« less

Control of ethanol withdrawal symptoms in mice by phenytoin.

PubMed

Sprague, G L; Craigmill, A L

1976-12-01

Mice were made physically dependent upon ethanol using either of two methods which involved ethanol vapor inhalation. Following the cessation of exposure to ethanol, the severity of handling-induced convulsions and changes in the response to an electric foot shock (startle reflex) were recorded. Animals given isotonic saline or propylene glycol:ethanol vehicle during withdrawal exhibited handling-induced convulsions, and ethanol (2.0-4.0 g/kg) or phenytoin (5-20 mg/kg) administration during withdrawal resulted in a reduction in the severity of these convulsions. A reduced startle reflex threshold was also evident during withdrawal in mice given isotonic saline or propylene glycol:ethanol vehicle. Ethanol (0.5-4.0 g/kg) or phenytoin (10-20 mg/kg) administration during withdrawal resulted in a significant elevation of the startle reflex threshold compared to control animals. The results are discussed as they relate to others obtained in experimental and clinical studies.

Bile Acid Sodium Symporter BASS6 Can Transport Glycolate and Is Involved in Photorespiratory Metabolism in Arabidopsis thaliana[OPEN

PubMed Central

Badger, Murray

2017-01-01

Photorespiration is an energy-intensive process that recycles 2-phosphoglycolate, a toxic product of the Rubisco oxygenation reaction. The photorespiratory pathway is highly compartmentalized, involving the chloroplast, peroxisome, cytosol, and mitochondria. Though the soluble enzymes involved in photorespiration are well characterized, very few membrane transporters involved in photorespiration have been identified to date. In this work, Arabidopsis thaliana plants containing a T-DNA disruption of the bile acid sodium symporter BASS6 show decreased photosynthesis and slower growth under ambient, but not elevated CO2. Exogenous expression of BASS6 complemented this photorespiration mutant phenotype. In addition, metabolite analysis and genetic complementation of glycolate transport in yeast showed that BASS6 was capable of glycolate transport. This is consistent with its involvement in the photorespiratory export of glycolate from Arabidopsis chloroplasts. An Arabidopsis double knockout line of both BASS6 and the glycolate/glycerate transporter PLGG1 (bass6, plgg1) showed an additive growth defect, an increase in glycolate accumulation, and reductions in photosynthetic rates compared with either single mutant. Our data indicate that BASS6 and PLGG1 partner in glycolate export from the chloroplast, whereas PLGG1 alone accounts for the import of glycerate. BASS6 and PLGG1 therefore balance the export of two glycolate molecules with the import of one glycerate molecule during photorespiration. PMID:28351992

A novel derivatization-free method of formaldehyde and propylene glycol determination in hydrogels by liquid chromatography with refractometric detection.

PubMed

Isakau, Henadz; Robert, Marielle; Shingel, Kirill I

2009-04-05

The paper describes the development and validation of a new derivatization-free liquid chromatography method for simultaneous determination of propylene glycol and formaldehyde in the formulations containing formaldehyde-releasing preservative. Highly swollen hydrogel made of poly(ethylene glycol)-protein conjugates was taken as a model formulation for integration of the propylene glycol and the diazolydinyl urea as formaldehyde releaser. The method is shown to be simple and selective and, more importantly, allows determining an existing level of formaldehyde at the moment of analysis instead of all available formaldehyde that might be released during chemical derivatization. After liquid extraction the propylene glycol (PG) and formaldehyde (FA) amounts are determined chromatographically on a Shodex SH 1011 ligand-exchange column using 0.01 M sulfuric acid mobile phase, a flow rate of 1.0 ml/min and RI detection. The assay is validated showing good linearity, precision, and accuracy. The limits of detection of formaldehyde and propylene glycol in the analyzed solutions were estimated to be 25 ng and 87 ng, respectively. This analytical assay is considered useful for product stability studies and in developing new formaldehyde releaser-containing formulations where the concentration of formaldehyde is a presumable subject of labeling requirements. This method can also provide a rapid and convenient alternative to gas chromatography method of propylene glycol quantification.

Minimization of Residual Stress in an Al-Cu Alloy Forged Plate by Different Heat Treatments

NASA Astrophysics Data System (ADS)

Dong, Ya-Bo; Shao, Wen-Zhu; Jiang, Jian-Tang; Zhang, Bao-You; Zhen, Liang

2015-06-01

In order to improve the balance of mechanical properties and residual stress, various quenching and aging treatments were applied to Al-Cu alloy forged plate. Residual stresses determined by the x-ray diffraction method and slitting method were compared. The surface residual stress measured by x-ray diffraction method was consistent with that measured by slitting method. The residual stress distribution of samples quenched in water with different temperatures (20, 60, 80, and 100 °C) was measured, and the results showed that the boiling water quenching results in a 91.4% reduction in residual stress magnitudes compared with cold water quenching (20 °C), but the tensile properties of samples quenched in boiling water were unacceptably low. Quenching in 80 °C water results in 75% reduction of residual stress, and the reduction of yield strength is 12.7%. The residual stress and yield strength level are considerable for the dimensional stability of aluminum alloy. Quenching samples into 30% polyalkylene glycol quenchants produced 52.2% reduction in the maximum compressive residual stress, and the reduction in yield strength is 19.7%. Moreover, the effects of uphill quenching and thermal-cold cycling on the residual stress were also investigated. Uphill quenching and thermal-cold cycling produced approximately 25-40% reduction in residual stress, while the effect on tensile properties is quite slight.

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...

One-pot wet-chemical co-reduction synthesis of bimetallic gold-platinum nanochains supported on reduced graphene oxide with enhanced electrocatalytic activity

NASA Astrophysics Data System (ADS)

Chen, De-Jun; Zhang, Qian-Li; Feng, Jin-Xia; Ju, Ke-Jian; Wang, Ai-Jun; Wei, Jie; Feng, Jiu-Ju

2015-08-01

In this work, a simple, rapid and facile one-pot wet-chemical co-reduction method is developed for synthesis of bimetallic Au-Pt alloyed nanochains supported on reduced graphene oxide (Au-Pt NCs/RGO), in which caffeine is acted as a capping agent and a structure-directing agent, while no any seed, template, surfactant or polymer involved. The as-prepared nanocomposites display enlarged electrochemical active surface area, significantly enhanced catalytic activity and better stability for methanol and ethylene glycol oxidation, compared with commercial Pt-C (Pt 50 wt%), PtRu-C (Pt 30 wt% and Ru 15 wt%) and Pt black.

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.

Organics Characterization Of DWPF Alternative Reductant Simulants, Glycolic Acid, And Antifoam 747

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

White, T. L.; Wiedenman, B. J.; Lambert, D. P.

The present study examines the fate of glycolic acid and other organics added in the Chemical Processing Cell (CPC) of the Defense Waste Processing Facility (DWPF) as part of the glycolic alternate flowsheet. Adoption of this flowsheet is expected to provide certain benefits in terms of a reduction in the processing time, a decrease in hydrogen generation, simplification of chemical storage and handling issues, and an improvement in the processing characteristics of the waste stream including an increase in the amount of nitrate allowed in the CPC process. Understanding the fate of organics in this flowsheet is imperative because tankmore » farm waste processed in the CPC is eventually immobilized by vitrification; thus, the type and amount of organics present in the melter feed may affect optimal melt processing and the quality of the final glass product as well as alter flammability calculations on the DWPF melter off gas. To evaluate the fate of the organic compounds added as the part of the glycolic flowsheet, mainly glycolic acid and antifoam 747, samples of simulated waste that was processed using the DWPF CPC protocol for tank farm sludge feed were generated and analyzed for organic compounds using a variety of analytical techniques at the Savannah River National Laboratory (SRNL). These techniques included Ion Chromatography (IC), Gas Chromatography-Mass Spectrometry (GC-MS), Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES), and Nuclear Magnetic Resonance (NMR) Spectroscopy. A set of samples were also sent to the Catholic University of America Vitreous State Laboratory (VSL) for analysis by NMR Spectroscopy at the University of Maryland, College Park. Analytical methods developed and executed at SRNL collectively showed that glycolic acid was the most prevalent organic compound in the supernatants of Slurry Mix Evaporator (SME) products examined. Furthermore, the studies suggested that commercially available glycolic acid contained minor amounts of impurities such as formic and diglycolic acid that were then carried over in the SME products. Oxalic acid present in the simulated tank farm waste was also detected. Finally, numerous other compounds, at low concentrations, were observed present in etheric extracts of aqueous supernate solutions of the SME samples and are thought to be breakdown products of antifoam 747. The data collectively suggest that although addition of glycolic acid and antifoam 747 will introduce a number of impurities and breakdown products into the melter feed, the concentrations of these organics is expected to remain low and may not significantly impact REDOX or off-gas flammability predictions. In the SME products examined presently, which contained variant amounts of glycolic acid and antifoam 747, no unexpected organic degradation product was found at concentrations above 500 mg/kg, a reasonable threshold concentration for an organic compound to be taken into account in the REDOX modeling. This statement does not include oxalic or formic acid that were sometimes observed above 500 mg/kg and acetic acid that has an analytical detection limit of 1250 mg/kg due to high glycolate concentration in the SME products tested. Once a finalized REDOX equation has been developed and implemented, REDOX properties of known organic species will be determined and their impact assessed. Although no immediate concerns arose during the study in terms of a negative impact of organics present in SME products of the glycolic flowsheet, evidence of antifoam degradation suggest that an alternative antifoam to antifoam 747 is worth considering. The determination and implementation of an antifoam that is more hydrolysis resistant would have benefits such as increasing its effectiveness over time and reducing the generation of degradation products.« less

Thymol nanoemulsified by whey protein-maltodextrin conjugates: the enhanced emulsifying capacity and antilisterial properties in milk by propylene glycol.

PubMed

Xue, Jia; Davidson, P Michael; Zhong, Qixin

2013-12-26

The objective of this research was to enhance the capability of whey protein isolate-maltodextrin conjugates in nanoemulsifying thymol using propylene glycol to improve antilisterial properties in milk. Thymol was predissolved in PG and emulsified in 7% conjugate solution. Transparent dispersions with mean diameters of <30 nm were observed up to 1.5%w/v thymol. In skim and 2% reduced fat milk, Listeria monocytogenes Scott A was reduced from ∼5 log CFU/mL to below the detection limit in 6 h by 0.1% w/v and 0.45% w/v nanoemulsified thymol, respectively, contrasting with gradual reductions to 1.15 and 2.26 log CFU/mL after 48 h by same levels of free thymol. In full fat milk, L. monocytogenes was gradually reduced to be undetectable after 48 h by 0.6% w/v nanoemulsified thymol, contrasting with the insignificant reduction by free thymol. The improved antilisterial activities of nanoemulsified thymol resulted from the increased solubility in milk and synergistic activity with propylene glycol.

The Verification of a Method for Detecting and Quantifying Diethylene Glycol, Triethylene Glycol, Tetraethylene Glycol, 2-Butoxyethanol and 2-Methoxyethanolin in Ground and Surface Waters

EPA Science Inventory

This verification study was a special project designed to determine the efficacy of a draft standard operating procedure (SOP) developed by US EPA Region 3 for the determination of selected glycols in drinking waters that may have been impacted by active unconventional oil and ga...

Studies on the reaction mechanism of lactate oxidase. Formation of two covalent flavin-substrate adducts on reaction with glycollate.

PubMed

Massey, V; Ghisla, S; Kieschke, K

1980-04-10

L-Lactate oxidase from Mycobacterium smegmatis catalyzes the oxidative decarboxylation of glycollate, with formate, CO2, and H2O as the major products. In addition, some "uncoupling" of the normal reaction occurs, with glyoxylate and H2O adition, some "uncoupling" of the normal reaction occurs, with glyoxylate and H2O2 as products. Glyoxylate is also a substrate (presumably as its hydrate); in this case, the reaction products are oxalate and H2O2. Evidence is presented that the enzyme recognizes glycollate as a prochiral substrate, differentiating between the Re- and Si-faces of the alpha carbon atom. Two highly fluorescent species are formed concomitantly from the reaction with glycollate; they are proposed to be covalent alpha-glycollyl adducts to the reduced flavin position N(5). One of these adducts is labile and in rapid equilibrium with oxidized enzyme and glycollate, and with the complex of reduced enzyme and glyoxylate; this adduct is a catalytically competent intermediate. The other adduct is comparatively stable (t 1/2 for decay = 20 min at 25 degrees C) and does not react with O2. It is formed at a rate approximately 1% that of the catalytic adduct, but because of its lack of reaction with O2 and its stability, it gradually accumulates during catalytic turnover, resulting in catalytically incompetent enzyme. An isotope effect of approximately 4 is found in the reduction of oxidized enzyme flavin and in the formation of the labile fluorescent adduct, when alpha-2H2-glycollate or (R)-glycollate-2-d is used, but not with the (S)-glycollate-2-d enantiomer. It is concluded that the catalytic adduct is formed by hydrogen abstraction from the Re-face of glycollate.

Synthesis and characterization of poly(lactic acid-co-glycolic acid) complex microspheres as drug carriers.

PubMed

Wang, Fang; Liu, Xiuxiu; Yuan, Jian; Yang, Siqian; Li, Yueqin; Gao, Qinwei

2016-10-01

Poly(lactic-co-glycolic) acid (PLGA) is synthesized via melt polycondensation directly from lactic acid and glycolic acid with a feed molar ratio of 75/25. Bovine serum albumin, which is used as model protein, is entrapped into the poly(lactic-co-glycolic acid) microspheres with particle size of 260.9 ± 20.0 nm by the double emulsification method. Then it is the first report of producing more carboxyl groups by poly(lactic-co-glycolic acid) surface hydrolysis. The purpose is developing poly(lactic-co-glycolic acid) microspheres surface, which is modified with chitosan by chemical reaction between carboxyl groups and amine groups. The particle size and the positive zeta potential of the poly(lactic-co-glycolic acid)/chitosan microspheres are 388.2 ± 35.6 nm and 10.4 ± 2.9 mV, respectively. The drug loading ratio and encapsulation efficacy of poly(lactic-co-glycolic acid)/chitosan microspheres are 36.3% and 57.5%, which are higher than PLGA microspheres. Furthermore, the drug burst release of poly(lactic-co-glycolic acid)/chitosan microspheres at 10 h is decreased to 21.72% while the corresponding value of the poly(lactic-co-glycolic acid) microsphere is 64.56%. These results reveal that surface hydrolysis modification of poly(lactic-co-glycolic acid) is an efficient method to improve the negative potential and chemical reaction properties of the polymer. And furthermore, this study shows that chitosan-modified poly(lactic-co-glycolic acid) microspheres is a promising system for the controlled release of pharmaceutical proteins. © The Author(s) 2016.

Assessment and management of aquatic impacts from airport de-icing activities -- The Canadian perspective

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

Kent, R.A.; Andersen, D.; Simpson, A.

1995-12-31

Historically, aircraft deicing fluids have simply drained from aircraft and runway surfaces into airport drainage systems and invariably end up in surrounding receiving aquatic systems. This led to recent concerns over environmental impacts from glycol-based fluids typically used for deicing aircraft. Glycols from de-icing fluids have been detected at high levels at Canadian airports. Concern not only stems from the high volumes being used at relatively few point sources, but also to the higher toxicity of the formulated de-icing fluids, compared to pure glycols. As a result, significant environmental management efforts have been made at Canadian airports over the lastmore » 4 years, including extensive stormwater monitoring, glycol mitigation and pollution prevention plans. Site-specific mitigation plans have been implemented at 15 major Canadian airports which typically include glycol containment, collection and removal. While a reasonable dataset is available on the toxicity of pure glycols, much less information is available on the toxicity of formulated deicers. Furthermore, there have been very few field assessments of the aquatic impacts of de-icing. To date, management regimes developed to address the problem in Canada have focused almost exclusively on glycols and voluntary compliance to discharge limits and receiving water quality guidelines. This approach has resulted in reductions in the quantities of glycols which are released from Canadian airports into the surrounding environment. Currently, government and industry are refining this management system with an examination of new approaches and options such as more holistic airport wastewater quality assessments and toxicity-based guidelines.« less

Durability Improvement of Pt/RGO Catalysts for PEMFC by Low-Temperature Self-Catalyzed Reduction.

PubMed

Sun, Kang Gyu; Chung, Jin Suk; Hur, Seung Hyun

2015-12-01

Pt/C catalyst used for polymer electrolyte membrane fuel cells (PEMFCs) displays excellent initial performance, but it does not last long because of the lack of durability. In this study, a Pt/reduced graphene oxide (RGO) catalyst was synthesized by the polyol method using ethylene glycol (EG) as the reducing agent, and then low-temperature hydrogen bubbling (LTHB) treatment was introduced to enhance the durability of the Pt/RGO catalyst. The cyclic voltammetry (CV), oxygen reduction reaction (ORR) analysis, and transmittance electron microscopy (TEM) results suggested that the loss of the oxygen functional groups, because of the hydrogen spillover and self-catalyzed dehydration reaction during LTHB, reduced the carbon corrosion and Pt agglomeration and thus enhanced the durability of the electrocatalyst.

Individual Reactions of Permanganate and Various Reductants - Student Report to the DOE ERULF Program for Work Conducted May to July 2000

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

Gauger, Amber M.; Hallen, Richard T.

2012-09-15

Tank waste on the Hanford Site contains radioactive elements that need to be removed from solution prior to disposal. One effective way to do this is to precipitate the radioactive elements with manganese solids, produced by permanganate oxidation. When added to tank waste, the permanganate reacts quickly producing manganese (IV) dioxide precipitate. Because of the speed of the reaction it is difficult to tell what exactly is happening. Individual reactions using non-radioactive reductants found in the tanks were done to determine reaction kinetics, what permanganate was reduced to, and what oxidation products were formed. In this project sodium formate, sodiummore » nitrite, glycolic acid, glycine, and sodium oxalate were studied using various concentrations of reductant in alkaline sodium hydroxide solutions. It was determined that formate reacted the quickest, followed by glycine and glycolic acid. Oxalate and nitrite did not appear to react with the permanganate solutions. The products of the oxidation reaction were examined. Formate was oxidized to carbonate and water. Glycolic acid was oxidized slower producing oxalate and water. Glycine reactions formed some ammonia in solution, oxalate, and water. The research reported by Amber Gauger in this report was part of a DOE ERULF student intern program at Pacific Northwest National Laboratory under the direction of Richard Hallen in the summer of 2000.« less

Enhancements of thermal conductivities with Cu, CuO, and carbon nanotube nanofluids and application of MWNT/water nanofluid on a water chiller system

NASA Astrophysics Data System (ADS)

Liu, Minsheng; Lin, Mark Chingcheng; Wang, Chichuan

2011-12-01

In this study, enhancements of thermal conductivities of ethylene glycol, water, and synthetic engine oil in the presence of copper (Cu), copper oxide (CuO), and multi-walled carbon nanotube (MWNT) are investigated using both physical mixing method (two-step method) and chemical reduction method (one-step method). The chemical reduction method is, however, used only for nanofluid containing Cu nanoparticle in water. The thermal conductivities of the nanofluids are measured by a modified transient hot wire method. Experimental results show that nanofluids with low concentration of Cu, CuO, or carbon nanotube (CNT) have considerably higher thermal conductivity than identical base liquids. For CuO-ethylene glycol suspensions at 5 vol.%, MWNT-ethylene glycol at 1 vol.%, MWNT-water at 1.5 vol.%, and MWNT-synthetic engine oil at 2 vol.%, thermal conductivity is enhanced by 22.4, 12.4, 17, and 30%, respectively. For Cu-water at 0.1 vol.%, thermal conductivity is increased by 23.8%. The thermal conductivity improvement for CuO and CNT nanofluids is approximately linear with the volume fraction. On the other hand, a strong dependence of thermal conductivity on the measured time is observed for Cu-water nanofluid. The system performance of a 10-RT water chiller (air conditioner) subject to MWNT/water nanofluid is experimentally investigated. The system is tested at the standard water chiller rating condition in the range of the flow rate from 60 to 140 L/min. In spite of the static measurement of thermal conductivity of nanofluid shows only 1.3% increase at room temperature relative to the base fluid at volume fraction of 0.001 (0.1 vol.%), it is observed that a 4.2% increase of cooling capacity and a small decrease of power consumption about 0.8% occur for the nanofluid system at a flow rate of 100 L/min. This result clearly indicates that the enhancement of cooling capacity is not just related to thermal conductivity alone. Dynamic effect, such as nanoparticle dispersion may effectively augment the system performance. It is also found that the dynamic dispersion is comparatively effective at lower flow rate regime, e.g., transition or laminar flow and becomes less effective at higher flow rate regime. Test results show that the coefficient of performance of the water chiller is increased by 5.15% relative to that without nanofluid.

Enhancements of thermal conductivities with Cu, CuO, and carbon nanotube nanofluids and application of MWNT/water nanofluid on a water chiller system

PubMed Central

2011-01-01

In this study, enhancements of thermal conductivities of ethylene glycol, water, and synthetic engine oil in the presence of copper (Cu), copper oxide (CuO), and multi-walled carbon nanotube (MWNT) are investigated using both physical mixing method (two-step method) and chemical reduction method (one-step method). The chemical reduction method is, however, used only for nanofluid containing Cu nanoparticle in water. The thermal conductivities of the nanofluids are measured by a modified transient hot wire method. Experimental results show that nanofluids with low concentration of Cu, CuO, or carbon nanotube (CNT) have considerably higher thermal conductivity than identical base liquids. For CuO-ethylene glycol suspensions at 5 vol.%, MWNT-ethylene glycol at 1 vol.%, MWNT-water at 1.5 vol.%, and MWNT-synthetic engine oil at 2 vol.%, thermal conductivity is enhanced by 22.4, 12.4, 17, and 30%, respectively. For Cu-water at 0.1 vol.%, thermal conductivity is increased by 23.8%. The thermal conductivity improvement for CuO and CNT nanofluids is approximately linear with the volume fraction. On the other hand, a strong dependence of thermal conductivity on the measured time is observed for Cu-water nanofluid. The system performance of a 10-RT water chiller (air conditioner) subject to MWNT/water nanofluid is experimentally investigated. The system is tested at the standard water chiller rating condition in the range of the flow rate from 60 to 140 L/min. In spite of the static measurement of thermal conductivity of nanofluid shows only 1.3% increase at room temperature relative to the base fluid at volume fraction of 0.001 (0.1 vol.%), it is observed that a 4.2% increase of cooling capacity and a small decrease of power consumption about 0.8% occur for the nanofluid system at a flow rate of 100 L/min. This result clearly indicates that the enhancement of cooling capacity is not just related to thermal conductivity alone. Dynamic effect, such as nanoparticle dispersion may effectively augment the system performance. It is also found that the dynamic dispersion is comparatively effective at lower flow rate regime, e.g., transition or laminar flow and becomes less effective at higher flow rate regime. Test results show that the coefficient of performance of the water chiller is increased by 5.15% relative to that without nanofluid. PMID:21711787

Enhancements of thermal conductivities with Cu, CuO, and carbon nanotube nanofluids and application of MWNT/water nanofluid on a water chiller system.

PubMed

Liu, Minsheng; Lin, Mark Chingcheng; Wang, Chichuan

2011-04-05

In this study, enhancements of thermal conductivities of ethylene glycol, water, and synthetic engine oil in the presence of copper (Cu), copper oxide (CuO), and multi-walled carbon nanotube (MWNT) are investigated using both physical mixing method (two-step method) and chemical reduction method (one-step method). The chemical reduction method is, however, used only for nanofluid containing Cu nanoparticle in water. The thermal conductivities of the nanofluids are measured by a modified transient hot wire method. Experimental results show that nanofluids with low concentration of Cu, CuO, or carbon nanotube (CNT) have considerably higher thermal conductivity than identical base liquids. For CuO-ethylene glycol suspensions at 5 vol.%, MWNT-ethylene glycol at 1 vol.%, MWNT-water at 1.5 vol.%, and MWNT-synthetic engine oil at 2 vol.%, thermal conductivity is enhanced by 22.4, 12.4, 17, and 30%, respectively. For Cu-water at 0.1 vol.%, thermal conductivity is increased by 23.8%. The thermal conductivity improvement for CuO and CNT nanofluids is approximately linear with the volume fraction. On the other hand, a strong dependence of thermal conductivity on the measured time is observed for Cu-water nanofluid. The system performance of a 10-RT water chiller (air conditioner) subject to MWNT/water nanofluid is experimentally investigated. The system is tested at the standard water chiller rating condition in the range of the flow rate from 60 to 140 L/min. In spite of the static measurement of thermal conductivity of nanofluid shows only 1.3% increase at room temperature relative to the base fluid at volume fraction of 0.001 (0.1 vol.%), it is observed that a 4.2% increase of cooling capacity and a small decrease of power consumption about 0.8% occur for the nanofluid system at a flow rate of 100 L/min. This result clearly indicates that the enhancement of cooling capacity is not just related to thermal conductivity alone. Dynamic effect, such as nanoparticle dispersion may effectively augment the system performance. It is also found that the dynamic dispersion is comparatively effective at lower flow rate regime, e.g., transition or laminar flow and becomes less effective at higher flow rate regime. Test results show that the coefficient of performance of the water chiller is increased by 5.15% relative to that without nanofluid.

A ring to rule them all: a cyclic ketene acetal comonomer controls the nitroxide-mediated polymerization of methacrylates and confers tunable degradability.

PubMed

Delplace, Vianney; Guégain, Elise; Harrisson, Simon; Gigmes, Didier; Guillaneuf, Yohann; Nicolas, Julien

2015-08-18

2-Methylene-4-phenyl-1,3-dioxolane (MPDL) was successfully used as a controlling comonomer in NMP with oligo(ethylene glycol) methyl ether methacrylate (MeOEGMA) to prepare well-defined and degradable PEG-based P(MeOEGMA-co-MPDL) copolymers. The level of ester group incorporation is controlled, leading to reductions in molecular weight of up to 95% on hydrolysis. Neither the polymer nor its degradation products displayed cytoxicity. The method was also successfully applied to methyl methacrylate.

Defense Waste Processing Facility Nitric- Glycolic Flowsheet Chemical Process Cell Chemistry: Part 2

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

Zamecnik, J.; Edwards, T.

The conversions of nitrite to nitrate, the destruction of glycolate, and the conversion of glycolate to formate and oxalate were modeled for the Nitric-Glycolic flowsheet using data from Chemical Process Cell (CPC) simulant runs conducted by Savannah River National Laboratory (SRNL) from 2011 to 2016. The goal of this work was to develop empirical correlation models to predict these values from measureable variables from the chemical process so that these quantities could be predicted a-priori from the sludge or simulant composition and measurable processing variables. The need for these predictions arises from the need to predict the REDuction/OXidation (REDOX) statemore » of the glass from the Defense Waste Processing Facility (DWPF) melter. This report summarizes the work on these correlations based on the aforementioned data. Previous work on these correlations was documented in a technical report covering data from 2011-2015. This current report supersedes this previous report. Further refinement of the models as additional data are collected is recommended.« less

Effects of polyphenols from grape seeds on renal lithiasis.

PubMed

Grases, Felix; Prieto, Rafel M; Fernandez-Cabot, Rafel A; Costa-Bauzá, Antonia; Tur, Fernando; Torres, Jose Juan

2015-01-01

Nephrolithiasis is a complex disease that results from a combination of factors related to both urine composition and kidney morphoanatomy. Development of calcium oxalate monohydrate papillary calculi is linked to initial subepithelial calcification of renal papilla. Progressive tissue calcification depends on preexisting injury and involves reactive oxygen species. Many plant extracts that protect against oxidative stress manifest antilithiasic activity. Our study focused on determining the effects of polyphenols on a lithiasis rat model. Rats were pretreated with polyphenols and grape seed extracts, followed by posterior induction of hyperoxalosis via treatment with ethylene glycol plus NH4Cl. The concentrations of calcium and other elements in kidney were determined, along with histological examination of kidney and 24 h urine analysis. Significant differences were observed in the renal calcium content between the control plus ethylene glycol-treated group and the epicatechin plus ethylene glycol-treated, red grape seed extract plus ethylene glycol-treated, and white grape seed extract plus ethylene glycol-treated groups, with reductions of about 50%. The antioxidant activity of polyphenols extracted from red and white grape seeds may be critical in the prevention of calcium oxalate monohydrate papillary calculus formation, particularly if calculi are induced by lesions caused by cytotoxic compounds with oxidative capacity.

Solvothermal synthesis of N-doped graphene supported PtCo nanodendrites with highly catalytic activity for 4-nitrophenol reduction

NASA Astrophysics Data System (ADS)

Zhang, Xiao-Fang; Zhu, Xiao-Yan; Feng, Jiu-Ju; Wang, Ai-Jun

2018-01-01

A simple solvothermal method was developed to prepare N-doped reduced graphene oxide supported homogeneous PtCo nanodendrites (PtCo NDs/N-rGO), where ethylene glycol (EG) served as the reducing agent and the solvent, and linagliptin as the structure-directing and stabilizing agent for PtCo NDs and dopant for rGO, respectively. Controlled researches showed that the dosage of linagliptin and the ratios of the two metal precursors were important in the current synthesis. The PtCo NDs/N-rGO nanocomposite exhibited higher catalytic activity towards the reduction of 4-nitrophnol (4-NP) in contrast with the referenced Pt1Co3 NCs/N-rGO, Pt3Co1 NCs/N-rGO and commercial Pt/C catalysts. More importantly, the constructed catalyst exhibited the superior stability without sacrificing the catalytic activity, showing great prospect for the reduction of 4-NP in practice.

Diagnosis of toxic alcohols: limitations of present methods.

PubMed

Kraut, Jeffrey A

2015-01-01

Methanol, ethylene glycol, diethylene glycol, and propylene glycol intoxications are associated with cellular dysfunction and an increased risk of death. Adverse effects can develop quickly; thus, there is a need for methods for rapidly detecting their presence. To examine the value and limitations of present methods to diagnose patients with possible toxic alcohol exposure. I searched MEDLINE for articles published between 1969 and 2014 using the terms: toxic alcohols, serum osmolality, serum osmol gap, serum anion gap, metabolic acidosis, methanol, ethylene glycol, diethylene glycol, propylene glycol, and fomepizole. Each article was reviewed for additional references. The diagnosis of toxic alcohol exposure is often made on the basis of this history and physical findings along with an increase in the serum osmol and anion gaps. However, an increase in the osmol and/or anion gaps is not always present. Definitive detection in blood requires gas or liquid chromatography, laborious and expensive procedures which are not always available. Newer methods including a qualitative colorimetric test for detection of all alcohols or enzymatic tests for a specific alcohol might allow for more rapid diagnosis. Exposure to toxic alcohols is associated with cellular dysfunction and increased risk of death. Treatment, if initiated early, can markedly improve outcome, but present methods of diagnosis including changes in serum osmol and anion gap, and use of gas or liquid chromatography have important limitations. Development of more rapid and effective tests for detection of these intoxications is essential for optimal care of patients.

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

Zamecnik, J. R.; Edwards, T. B.

The conversions of nitrite to nitrate, the destruction of glycolate, and the conversion of glycolate to formate and oxalate were modeled for the Nitric-Glycolic flowsheet using data from Chemical Process Cell (CPC) simulant runs conducted by SRNL from 2011 to 2015. The goal of this work was to develop empirical correlations for these variables versus measureable variables from the chemical process so that these quantities could be predicted a-priori from the sludge composition and measurable processing variables. The need for these predictions arises from the need to predict the REDuction/OXidation (REDOX) state of the glass from the Defense Waste Processingmore » Facility (DWPF) melter. This report summarizes the initial work on these correlations based on the aforementioned data. Further refinement of the models as additional data is collected is recommended.« less

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)

Concentration of Nicotine and Glycols in 27 Electronic Cigarette Formulations

PubMed Central

Peace, Michelle R.; Baird, Tyson R.; Smith, Nathaniel; Wolf, Carl E.; Poklis, Justin L.; Poklis, Alphonse

2016-01-01

Personal battery-powered vaporizers or electronic cigarettes were developed to deliver a nicotine vapor such that smokers could simulate smoking tobacco without the inherent pathology of inhaled tobacco smoke. Electronic cigarettes and their e-cigarette liquid formulations are virtually unregulated. These formulations are typically composed of propylene glycol and/or glycerin, flavoring components and an active drug, such as nicotine. Twenty-seven e-cigarette liquid formulations that contain nicotine between 6 and 22 mg/L were acquired within the USA and analyzed by various methods to determine their contents. They were screened by Direct Analysis in Real Time™ Mass Spectrometry (DART-MS). Nicotine was confirmed and quantitated by high-performance liquid chromatography–tandem mass spectrometry, and the glycol composition was confirmed and quantitated by gas chromatography–mass spectrometry. The DART-MS screening method was able to consistently identify the exact mass peaks resulting from the protonated molecular ion of nicotine, glycol and a number of flavor additives within 5 mmu. Nicotine concentrations were determined to range from 45 to 131% of the stated label concentration, with 18 of the 27 have >10% variance. Glycol composition was generally accurate to the product description, with only one exception where the propylene glycol to glycerin percentage ratio was stated as 50:50 and the determined concentration of propylene glycol to glycerin was 81:19 (% v/v). No unlabeled glycols were detected in these formulations. PMID:27165804

40 CFR 63.1282 - Test methods, compliance procedures, and compliance demonstrations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... demonstrations. (a) Determination of glycol dehydration unit flowrate or benzene emissions. The procedures of this paragraph shall be used by an owner or operator to determine glycol dehydration unit natural gas....1274(d). (1) The determination of actual flowrate of natural gas to a glycol dehydration unit shall be...

40 CFR 63.1282 - Test methods, compliance procedures, and compliance demonstrations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... demonstrations. (a) Determination of glycol dehydration unit flowrate or benzene emissions. The procedures of this paragraph shall be used by an owner or operator to determine glycol dehydration unit natural gas....1274(d). (1) The determination of actual flowrate of natural gas to a glycol dehydration unit shall be...

ACTUAL WASTE TESTING OF GYCOLATE IMPACTS ON THE SRS TANK FARM

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

Martino, C.

2014-05-28

Glycolic acid is being studied as a replacement for formic acid in the Defense Waste Processing Facility (DWPF) feed preparation process. After implementation, the recycle stream from DWPF back to the high-level waste Tank Farm will contain soluble sodium glycolate. Most of the potential impacts of glycolate in the Tank Farm were addressed via a literature review and simulant testing, but several outstanding issues remained. This report documents the actual-waste tests to determine the impacts of glycolate on storage and evaporation of Savannah River Site high-level waste. The objectives of this study are to address the following: Determine the extentmore » to which sludge constituents (Pu, U, Fe, etc.) dissolve (the solubility of sludge constituents) in the glycolate-containing 2H-evaporator feed. Determine the impact of glycolate on the sorption of fissile (Pu, U, etc.) components onto sodium aluminosilicate solids. The first objective was accomplished through actual-waste testing using Tank 43H and 38H supernatant and Tank 51H sludge at Tank Farm storage conditions. The second objective was accomplished by contacting actual 2H-evaporator scale with the products from the testing for the first objective. There is no anticipated impact of up to 10 g/L of glycolate in DWPF recycle to the Tank Farm on tank waste component solubilities as investigated in this test. Most components were not influenced by glycolate during solubility tests, including major components such as aluminum, sodium, and most salt anions. There was potentially a slight increase in soluble iron with added glycolate, but the soluble iron concentration remained so low (on the order of 10 mg/L) as to not impact the iron to fissile ratio in sludge. Uranium and plutonium appear to have been supersaturated in 2H-evaporator feed solution mixture used for this testing. As a result, there was a reduction of soluble uranium and plutonium as a function of time. The change in soluble uranium concentration was independent of added glycolate concentration. The change in soluble plutonium content was dependent on the added glycolate concentration, with higher levels of glycolate (5 g/L and 10 g/L) appearing to suppress the plutonium solubility. The inclusion of glycolate did not change the dissolution of or sorption onto actual-waste 2H-evaporator pot scale to an extent that will impact Tank Farm storage and concentration. The effects that were noted involved dissolution of components from evaporator scale and precipitation of components onto evaporator scale that were independent of the level of added glycolate.« less

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.

Effect of silver on the shape of palladium nanoparticles

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

Gupta, Dikshita, E-mail: dgmonugupta@gmail.com; Barman, P. B.; Hazra, S. K.

We report a facile route to prepare palladium-silver nanoparticles at considerably low temperature. First the controlled synthesis of palladium nanoparticles was performed via reduction of sodium tetrachloropalladate (II) in ethylene glycol in the presence of PVP(polyvinylpyrrolidone) as capping agent. The reaction was carried out at three different temperatures-80°C, 100°C and 120°C for one hour. Short reaction time and low synthesis temperature adds advantage to this method over others. Formed palladium nanoparticles were nearly spherical with the average particle size of 7.5±0.5 nm, 9.5±0.5 nm and 10.5±0.5 nm at 80°C, 100°C and 120°C respectively. Secondly, the palladium-silver nanoparticles were prepared bymore » the simultaneous reduction of palladium and silver from their respective precursors in ethylene glycol at 100°C (optimized temperature). The shape and size distribution was studied by TEM (Transmission Electron Microscopy). The role of silver in transforming the shape of palladium nanoparticles from spherical to triangular has been discussed. Spherical symmetry of palladium nanoparticles is disturbed by the interaction of silver ions on the crystal facets of palladium nanoparticles. From UV-vis spectra, the absorption maxima of palladium nanoparticles at 205 nm and absorption maxima of palladium-silver nanoparticles at 272 nm revealed the partial evidence of their formation.« less

Self-Assembly, Surface Activity and Structure of n-Octyl-β-D-thioglucopyranoside in Ethylene Glycol-Water Mixtures

PubMed Central

Ruiz, Cristóbal Carnero; Molina-Bolívar, José Antonio; Hierrezuelo, José Manuel; Liger, Esperanza

2013-01-01

The effect of the addition of ethylene glycol (EG) on the interfacial adsorption and micellar properties of the alkylglucoside surfactant n-octyl-β-d-thioglucopyranoside (OTG) has been investigated. Critical micelle concentrations (cmc) upon EG addition were obtained by both surface tension measurements and the pyrene 1:3 ratio method. A systematic increase in the cmc induced by the presence of the co-solvent was observed. This behavior was attributed to a reduction in the cohesive energy of the mixed solvent with respect to pure water, which favors an increase in the solubility of the surfactant with EG content. Static light scattering measurements revealed a decrease in the mean aggregation number of the OTG micelles with EG addition. Moreover, dynamic light scattering data showed that the effect of the surfactant concentration on micellar size is also controlled by the content of the co-solvent in the system. Finally, the effect of EG addition on the microstructure of OTG micelles was investigated using the hydrophobic probe Coumarin 153 (C153). Time-resolved fluorescence anisotropy decay curves of the probe solubilized in micelles were analyzed using the two-step model. The results indicate a slight reduction of the average reorientation time of the probe molecule with increasing EG in the mixed solvent system, thereby suggesting a lesser compactness induced by the presence of the co-solvent. PMID:23385232

Self-assembly, surface activity and structure of n-octyl-β-D-thioglucopyranoside in ethylene glycol-water mixtures.

PubMed

Ruiz, Cristóbal Carnero; Molina-Bolívar, José Antonio; Hierrezuelo, José Manuel; Liger, Esperanza

2013-02-05

The effect of the addition of ethylene glycol (EG) on the interfacial adsorption and micellar properties of the alkylglucoside surfactant n-octyl-β-D-thioglucopyranoside (OTG) has been investigated. Critical micelle concentrations (cmc) upon EG addition were obtained by both surface tension measurements and the pyrene 1:3 ratio method. A systematic increase in the cmc induced by the presence of the co-solvent was observed. This behavior was attributed to a reduction in the cohesive energy of the mixed solvent with respect to pure water, which favors an increase in the solubility of the surfactant with EG content. Static light scattering measurements revealed a decrease in the mean aggregation number of the OTG micelles with EG addition. Moreover, dynamic light scattering data showed that the effect of the surfactant concentration on micellar size is also controlled by the content of the co-solvent in the system. Finally, the effect of EG addition on the microstructure of OTG micelles was investigated using the hydrophobic probe Coumarin 153 (C153). Time-resolved fluorescence anisotropy decay curves of the probe solubilized in micelles were analyzed using the two-step model. The results indicate a slight reduction of the average reorientation time of the probe molecule with increasing EG in the mixed solvent system, thereby suggesting a lesser compactness induced by the presence of the co-solvent.

Thermal hydrogen reduction for preservation of mesoporous silica film nanocomposites with a hexagonal structure containing amphiphilic triphenylene

NASA Astrophysics Data System (ADS)

Lintang, Hendrik O.; Jalani, Mohamad Azani; Yuliati, Leny

2017-11-01

We highlight that columnar assembly of self-assembled templates was successfully utilized using sol-gel technique of mesostructured silica for the quality improvement of transparent mesoporous film nanocomposites with a hexagonal structure through appropriate heat treatment methods and self-assembled templates in the removal of organic components. In contrast to the reported mesostructured silica film nanocomposites containing columnar assembly of trinuclear gold(I) pyrazolate complex ([Au3Pz3]C10TEG/silicahex) with calcination at 450 °C, mesostructured silica film nanocomposites from self-assembled template of triphenylene bearing amphiphilic decoxy triethylene glycol side chains (TPC10TEG/silicahex) can be completely collapsed upon calcination at 450 °C. This hexagonal structure can be only preserved with calcination at 250 °C although intensity of its main diffraction peak of d100 at 2θ of 3.70° was significantly decreased. On the other hands, thermal hydrogen reduction at the same temperature was found to be the best heat treatment to preserve the quality of mesoporous silica film nanocomposites with decreasing in intensity of diffraction peak up to 30%. Such phenomenon might be caused by slow decomposition of organic components with the presence of hydrogen gas upon heating to shrinkage the silica wall from interpenetration of ethylene glycol segments of the side chains and to open bonding of benzene ring from the core.

Controlled method of reducing electrophoretic mobility of various substances

NASA Technical Reports Server (NTRS)

Vanalstine, James M. (Inventor)

1989-01-01

A method of reducing electrophoretic mobility of macromolecules, particles, cells, and the like is provided. The method comprises interacting the particles or cells with a polymer-linked affinity compound composed of: a hydrophilic neutral polymer such as polyethylene glycol, and an affinity component consisting of a hydrophobic compound such as a fatty acid ester, an immunocompound such as an antibody or active fragment thereof or simular macromolecule, or other ligands. The reduction of electrophoretic mobility achieved is directly proportional to the concentration of the polymer-linked affinity compound employed, and the mobility reduction obtainable is up to 100 percent for particular particles and cells. The present invention is advantageous in that analytical electrophoretic separation can not be achieved for macromolecules, particles, and cells whose native surface charge structure had prevented them from being separated by normal electrophoretic means. Depending on the affinity component utilized, separation can be achieved on the basis of specific/irreversible, specific/reversible, semi-specific/reversible, relatively nonspecific/reversible, or relatively nonspecific/irreversible ligand-substance interactions. The present method is also advantageous in that it can be used in a variety of standard laboratory electrophoresis equipment.

[Determination of ethylene glycol in biological fluids--propylene glycol interferences].

PubMed

Gomółka, Ewa; Cudzich-Czop, Sylwia; Sulka, Adrianna

2013-01-01

Many laboratories in Poland do not use gas chromatography (GC) method for determination of ethylene glycol (EG) and methanol in blood of poisoned patients, they use non specific spectrophotometry methods. One of the interfering substances is propylene glycol (PG)--compound present in many medical and cosmetic products: drops, air freshens, disinfectants, electronic cigarettes and others. In Laboratory of Analytical Toxicology and Drug Monitoring in Krakow determination of EG is made by GC method. The method enables to distinguish and make resolution of (EG) and (PG) in biological samples. In the years 2011-2012 in several serum samples from diagnosed patients PG was present in concentration from several to higher than 100 mg/dL. The aim of the study was to estimate PG interferences of serum EG determination by spectrophotometry method. Serum samples containing PG and EG were used in the study. The samples were analyzed by two methods: GC and spectrophotometry. Results of serum samples spiked with PG with no EG analysed by spectrophotometry method were improper ("false positive"). The results were correlated to PG concentration in samples. Calculated cross-reactivity of PG in the method was 42%. Positive results of EG measured by spectrophotometry method must be confirmed by reference GC method. Spectrophotometry method shouldn't be used for diagnostics and monitoring of patients poisoned by EG.

Effects of Polyphenols from Grape Seeds on Renal Lithiasis

PubMed Central

Grases, Felix; Prieto, Rafel M.; Fernandez-Cabot, Rafel A.; Costa-Bauzá, Antonia; Tur, Fernando; Torres, Jose Juan

2015-01-01

Nephrolithiasis is a complex disease that results from a combination of factors related to both urine composition and kidney morphoanatomy. Development of calcium oxalate monohydrate papillary calculi is linked to initial subepithelial calcification of renal papilla. Progressive tissue calcification depends on preexisting injury and involves reactive oxygen species. Many plant extracts that protect against oxidative stress manifest antilithiasic activity. Our study focused on determining the effects of polyphenols on a lithiasis rat model. Rats were pretreated with polyphenols and grape seed extracts, followed by posterior induction of hyperoxalosis via treatment with ethylene glycol plus NH4Cl. The concentrations of calcium and other elements in kidney were determined, along with histological examination of kidney and 24 h urine analysis. Significant differences were observed in the renal calcium content between the control plus ethylene glycol-treated group and the epicatechin plus ethylene glycol-treated, red grape seed extract plus ethylene glycol-treated, and white grape seed extract plus ethylene glycol-treated groups, with reductions of about 50%. The antioxidant activity of polyphenols extracted from red and white grape seeds may be critical in the prevention of calcium oxalate monohydrate papillary calculus formation, particularly if calculi are induced by lesions caused by cytotoxic compounds with oxidative capacity. PMID:25883748

Ethylene Glycol Adsorption and Reaction over CeOX(111) Thin Films

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

Mullins, David R; Chen, Tsung-Liang

2011-01-01

This study reports the interaction of ethylene glycol with well-ordered CeO{sub x}(111) thin film surfaces. Ethylene glycol initially adsorbs on fully oxidized CeO{sub 2}(111) and reduced CeO{sub 2-x}(111) through the formation of one C-O-Ce bond and then forms a second alkoxy bond after annealing. On fully oxidized CeO{sub 2}(111) both recombination of ethylene glycol and water desorption occur at low temperature leaving stable -OCH{sub 2}CH{sub 2}O- (ethylenedioxy) intermediates and oxygen vacancies on the surface. This ethylenedioxy intermediate goes through C-C bond scission to produce formate species which then react to produce CO and CO{sub 2}. The formation of water resultsmore » in the reduction of the ceria. On a reduced CeO{sub 2-x}(111) surface the reaction selectivity shifts toward a dehydration process. The ethylenedioxy intermediate decomposes by breaking a C-O bond and converts into an enolate species. Similar to the reaction of acetaldehyde on reduced CeO{sub 2-x}(111), the enolate reacts to produce acetaldehyde, acetylene, and ethylene. The loss of O from ethylene glycol leads to a small amount of oxidation of the reduced ceria.« less

Ethylene Glycol Adsorption and Reaction over CeOX(111) Thin Films

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

T Chen; D Mullins

2011-12-31

This study reports the interaction of ethylene glycol with well-ordered CeO{sub x}(111) thin film surfaces. Ethylene glycol initially adsorbs on fully oxidized CeO{sub 2}(111) and reduced CeO{sub 2-x}(111) through the formation of one C-O-Ce bond and then forms a second alkoxy bond after annealing. On fully oxidized CeO{sub 2}(111) both recombination of ethylene glycol and water desorption occur at low temperature leaving stable -OCH{sub 2}CH{sub 2}O- (ethylenedioxy) intermediates and oxygen vacancies on the surface. This ethylenedioxy intermediate goes through C-C bond scission to produce formate species which then react to produce CO and CO{sub 2}. The formation of water resultsmore » in the reduction of the ceria. On a reduced CeO{sub 2-x}(111) surface the reaction selectivity shifts toward a dehydration process. The ethylenedioxy intermediate decomposes by breaking a C-O bond and converts into an enolate species. Similar to the reaction of acetaldehyde on reduced CeO{sub 2-x}(111), the enolate reacts to produce acetaldehyde, acetylene, and ethylene. The loss of O from ethylene glycol leads to a small amount of oxidation of the reduced ceria.« less

Concentration of Nicotine and Glycols in 27 Electronic Cigarette Formulations.

PubMed

Peace, Michelle R; Baird, Tyson R; Smith, Nathaniel; Wolf, Carl E; Poklis, Justin L; Poklis, Alphonse

2016-07-01

Personal battery-powered vaporizers or electronic cigarettes were developed to deliver a nicotine vapor such that smokers could simulate smoking tobacco without the inherent pathology of inhaled tobacco smoke. Electronic cigarettes and their e-cigarette liquid formulations are virtually unregulated. These formulations are typically composed of propylene glycol and/or glycerin, flavoring components and an active drug, such as nicotine. Twenty-seven e-cigarette liquid formulations that contain nicotine between 6 and 22 mg/L were acquired within the USA and analyzed by various methods to determine their contents. They were screened by Direct Analysis in Real Time™ Mass Spectrometry (DART-MS). Nicotine was confirmed and quantitated by high-performance liquid chromatography-tandem mass spectrometry, and the glycol composition was confirmed and quantitated by gas chromatography-mass spectrometry. The DART-MS screening method was able to consistently identify the exact mass peaks resulting from the protonated molecular ion of nicotine, glycol and a number of flavor additives within 5 mmu. Nicotine concentrations were determined to range from 45 to 131% of the stated label concentration, with 18 of the 27 have >10% variance. Glycol composition was generally accurate to the product description, with only one exception where the propylene glycol to glycerin percentage ratio was stated as 50:50 and the determined concentration of propylene glycol to glycerin was 81:19 (% v/v). No unlabeled glycols were detected in these formulations. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

40 CFR 799.1560 - Diethylene glycol butyl ether and diethylene glycol butyl ether acetate.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Sadleir (1978) and the vaginal smear method in Hafez (1970) under paragraphs (d) (3) and (7) of this section or equivalent methods should be used. Data should be provided on whether the animal is cycling and... examined to adequately detail oocyte and follicular morphology. The methods of Mattison and Thorgiersson...

40 CFR 799.1560 - Diethylene glycol butyl ether and diethylene glycol butyl ether acetate.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Sadleir (1978) and the vaginal smear method in Hafez (1970) under paragraphs (d) (3) and (7) of this section or equivalent methods should be used. Data should be provided on whether the animal is cycling and... examined to adequately detail oocyte and follicular morphology. The methods of Mattison and Thorgiersson...

40 CFR 799.1560 - Diethylene glycol butyl ether and diethylene glycol butyl ether acetate.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Sadleir (1978) and the vaginal smear method in Hafez (1970) under paragraphs (d) (3) and (7) of this section or equivalent methods should be used. Data should be provided on whether the animal is cycling and... examined to adequately detail oocyte and follicular morphology. The methods of Mattison and Thorgiersson...

40 CFR 799.1560 - Diethylene glycol butyl ether and diethylene glycol butyl ether acetate.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Sadleir (1978) and the vaginal smear method in Hafez (1970) under paragraphs (d) (3) and (7) of this section or equivalent methods should be used. Data should be provided on whether the animal is cycling and... examined to adequately detail oocyte and follicular morphology. The methods of Mattison and Thorgiersson...

40 CFR 799.1560 - Diethylene glycol butyl ether and diethylene glycol butyl ether acetate.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Sadleir (1978) and the vaginal smear method in Hafez (1970) under paragraphs (d) (3) and (7) of this section or equivalent methods should be used. Data should be provided on whether the animal is cycling and... examined to adequately detail oocyte and follicular morphology. The methods of Mattison and Thorgiersson...

Nanofluids and a method of making nanofluids for ground source heat pumps and other applications

DOEpatents

Olson, John Melvin

2013-11-12

This invention covers nanofluids. Nanofluids are a combination of particles between 1 and 100 nanometers, a surfactant and the base fluid. The nanoparticles for this invention are either pyrogenic nanoparticles or carbon nanotubes. These nanofluids improve the heat transfer of the base fluids. The base fluid can be ethylene glycol, or propylene glycol, or an aliphatic-hydrocarbon based heat transfer fluid. This invention also includes a method of making nanofluids. No surfactant is used to suspend the pyrogenic nanoparticles in glycols.

Damage and recovery of skin barrier function after glycolic acid chemical peeling and crystal microdermabrasion.

PubMed

Song, Ji Youn; Kang, Hyun A; Kim, Mi-Yeon; Park, Young Min; Kim, Hyung Ok

2004-03-01

Superficial chemical peeling and microdermabrasion have become increasingly popular methods for producing facial rejuvenation. However, there are few studies reporting the skin barrier function changes after these procedures. To evaluate objectively the degree of damage visually and the time needed for the skin barrier function to recover after glycolic acid peeling and aluminum oxide crystal microdermabrasion using noninvasive bioengineering methods. Superficial chemical peeling using 30%, 50%, and 70% glycolic acid and aluminum oxide crystal microdermabrasion were used on the volar forearm of 13 healthy women. The skin response was measured by a visual observation and using an evaporimeter, corneometer, and colorimeter before and after peeling at set time intervals. Both glycolic acid peeling and aluminum oxide crystal microdermabrasion induced significant damage to the skin barrier function immediately after the procedure, and the degree of damage was less severe after the aluminum oxide crystal microdermabrasion compared with glycolic acid peeling. The damaged skin barrier function had recovered within 24 hours after both procedures. The degree of erythema induction was less severe after the aluminum oxide crystal microdermabrasion compared with the glycolic acid peeling procedure. The degree of erythema induced after the glycolic acid peeling procedure was not proportional to the peeling solution concentration used. The erythema subsided within 1 day after the aluminum oxide crystal microdermabrasion procedure and within 4 days after the glycolic acid peeling procedure. These results suggest that the skin barrier function is damaged after the glycolic acid peeling and aluminum oxide crystal microdermabrasion procedure but recovers within 1 to 4 days. Therefore, repeating the superficial peeling procedure at 2-week intervals will allow sufficient time for the damaged skin to recover its barrier function.

Universal electrode interface for electrocatalytic oxidation of liquid fuels.

PubMed

Liao, Hualing; Qiu, Zhipeng; Wan, Qijin; Wang, Zhijie; Liu, Yi; Yang, Nianjun

2014-10-22

Electrocatalytic oxidations of liquid fuels from alcohols, carboxylic acids, and aldehydes were realized on a universal electrode interface. Such an interface was fabricated using carbon nanotubes (CNTs) as the catalyst support and palladium nanoparticles (Pd NPs) as the electrocatalysts. The Pd NPs/CNTs nanocomposite was synthesized using the ethylene glycol reduction method. It was characterized using transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, voltammetry, and impedance. On the Pd NPs/CNTs nanocomposite coated electrode, the oxidations of those liquid fuels occur similarly in two steps: the oxidations of freshly chemisorbed species in the forward (positive-potential) scan and then, in the reverse scan (negative-potential), the oxidations of the incompletely oxidized carbonaceous species formed during the forward scan. The oxidation charges were adopted to study their oxidation mechanisms and oxidation efficiencies. The oxidation efficiency follows the order of aldehyde (formaldehyde) > carboxylic acid (formic acid) > alcohols (ethanol > methanol > glycol > propanol). Such a Pd NPs/CNTs nanocomposite coated electrode is thus promising to be applied as the anode for the facilitation of direct fuel cells.

Reducing surface tension in endodontic chelator solutions has no effect on their ability to remove calcium from instrumented root canals.

PubMed

Zehnder, Matthias; Schicht, Olivier; Sener, Beatrice; Schmidlin, Patrick

2005-08-01

The aim of this study was to evaluate the effect of reducing surface tension in endodontic chelator solutions on their ability to remove calcium from instrumented root canals. Aqueous solutions containing 15.5% EDTA, 10% citric acid, or 18% 1- hydroxyethylidene-1, 1-bisphosphonate (HEBP) were prepared with and without 1% (wt/wt) polysorbate (Tween) 80 and 9% propylene glycol. Surface tension in these solutions was measured using the Wilhelmy method. Sixty-four extracted, single-rooted human teeth of similar length were instrumented and irrigated with a 1% sodium hypochlorite solution and then randomly assigned (n = 8 per group) to receive a final one-minute rinse with 5 ml of test solutions, water, or the pure aqueous Tween/propylene glycol solution. Calcium concentration in eluates was measured using atomic absorption spectrometry. Incorporation of wetting agents resulted in a reduction of surface tension values by approximately 50% in all tested solutions. However, none of the solutions with reduced surface tension chelated more calcium from canals than their pure counterparts (p > 0.05).

LITERATURE REVIEW ON IMPACT OF GLYCOLATE ON THE 2H EVAPORATOR AND THE EFFLUENT TREATMENT FACILITY

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

Adu-Wusu, K.

2012-05-10

Glycolic acid (GA) is being studied as an alternate reductant in the Defense Waste Processing Facility (DWPF) feed preparation process. It will either be a total or partial replacement for the formic acid that is currently used. A literature review has been conducted on the impact of glycolate on two post-DWPF downstream systems - the 2H Evaporator system and the Effluent Treatment Facility (ETF). The DWPF recycle stream serves as a portion of the feed to the 2H Evaporator. Glycolate enters the evaporator system from the glycolate in the recycle stream. The overhead (i.e., condensed phase) from the 2H Evaporatormore » serves as a portion of the feed to the ETF. The literature search revealed that virtually no impact is anticipated for the 2H Evaporator. Glycolate may help reduce scale formation in the evaporator due to its high complexing ability. The drawback of the solubilizing ability is the potential impact on the criticality analysis of the 2H Evaporator system. It is recommended that at least a theoretical evaluation to confirm the finding that no self-propagating violent reactions with nitrate/nitrites will occur should be performed. Similarly, identification of sources of ignition relevant to glycolate and/or update of the composite flammability analysis to reflect the effects from the glycolate additions for the 2H Evaporator system are in order. An evaluation of the 2H Evaporator criticality analysis is also needed. A determination of the amount or fraction of the glycolate in the evaporator overhead is critical to more accurately assess its impact on the ETF. Hence, use of predictive models like OLI Environmental Simulation Package Software (OLI/ESP) and/or testing are recommended for the determination of the glycolate concentration in the overhead. The impact on the ETF depends on the concentration of glycolate in the ETF feed. The impact is classified as minor for feed glycolate concentrations {le} 33 mg/L or 0.44 mM. The ETF unit operations that will have minor/major impacts are chlorination, pH adjustment, 1st mercury removal, organics removal, 2nd mercury removal, and ion exchange. For minor impacts, the general approach is to use historical process operations data/modeling software like OLI/ESP and/or monitoring/compiled process operations data to resolve any uncertainties with testing as a last resort. For major impacts (i.e., glycolate concentrations > 33 mg/L or 0.44 mM), testing is recommended. No impact is envisaged for the following ETF unit operations regardless of the glycolate concentration - filtration, reverse osmosis, ion exchange resin regeneration, and evaporation.« less

Preparation and magnetic properties of nickel nanowires by reduction in ethylene glycol medium under the influence of magnetic field

NASA Astrophysics Data System (ADS)

Sun, Wanshuo; Cheng, Junsheng; Li, Lankai; Chen, Shunzhong; Chang, Kun

2017-01-01

Nickel nanowires have successfully been fabricated through a simple liquid reduction in ethylene glycol medium with a 0.3T magnetic field applied. The effect of uniform magnetic field and solvent on the morphology and the crystal structure of magnetic nickel were studied. Scanning electron microscope images and transmission electron scope images s how that the effect of the external magnetic field on the morphology of nickel nanowires. X-ray diffraction shows the crystal structure of as-prepared products. And a energy disperse spectroscopy and a vibrating sample magnetometer are used to analyze the composition and static magnetic properties. The results show that the straight wires with an average diameter of about 100 nm and a length of several microns were obtained and mainly composed by fcc structure in the solvent of ethylene glycol. Magnetic measurements show that the saturation magnetization of the as-obtained products in a 0.3 T external magnetic field is 36 emu/g, less than that of bulk nickel crystal, and the coercivity of them is 186 emu/g, larger than that of bulk crystal with the mole ratio of sodium borohydride to nickel sulfate is 1:1000. This kind of nanowires array has potential applications with the special one-dimensional structures.

Inhibition of Glycolate Oxidase With Dicer-substrate siRNA Reduces Calcium Oxalate Deposition in a Mouse Model of Primary Hyperoxaluria Type 1

PubMed Central

Dutta, Chaitali; Avitahl-Curtis, Nicole; Pursell, Natalie; Larsson Cohen, Marita; Holmes, Benjamin; Diwanji, Rohan; Zhou, Wei; Apponi, Luciano; Koser, Martin; Ying, Bo; Chen, Dongyu; Shui, Xue; Saxena, Utsav; Cyr, Wendy A; Shah, Anee; Nazef, Naim; Wang, Weimin; Abrams, Marc; Dudek, Henryk; Salido, Eduardo; Brown, Bob D; Lai, Chengjung

2016-01-01

Primary hyperoxaluria type 1 (PH1) is an autosomal recessive, metabolic disorder caused by mutations of alanine-glyoxylate aminotransferase (AGT), a key hepatic enzyme in the detoxification of glyoxylate arising from multiple normal metabolic pathways to glycine. Accumulation of glyoxylate, a precursor of oxalate, leads to the overproduction of oxalate in the liver, which accumulates to high levels in kidneys and urine. Crystalization of calcium oxalate (CaOx) in the kidney ultimately results in renal failure. Currently, the only treatment effective in reduction of oxalate production in patients who do not respond to high-dose vitamin B6 therapy is a combined liver/kidney transplant. We explored an alternative approach to prevent glyoxylate production using Dicer-substrate small interfering RNAs (DsiRNAs) targeting hydroxyacid oxidase 1 (HAO1) mRNA which encodes glycolate oxidase (GO), to reduce the hepatic conversion of glycolate to glyoxylate. This approach efficiently reduces GO mRNA and protein in the livers of mice and nonhuman primates. Reduction of hepatic GO leads to normalization of urine oxalate levels and reduces CaOx deposition in a preclinical mouse model of PH1. Our results support the use of DsiRNA to reduce liver GO levels as a potential therapeutic approach to treat PH1. PMID:26758691

Controlled method of reducing electrophoretic mobility of macromolecules, particles, or cells

NASA Technical Reports Server (NTRS)

Vanalstine, James M. (Inventor)

1992-01-01

A method of reducing electrophoretic mobility of macromolecules, particles, cells, and other substances is provided which comprises interacting in a conventional electrophoretic separating procedure, the substances with a polymer-linked affinity compound comprised of a hydrophilic neutral polymer such as polyethylene glycol bound to a second component such as a hydrophobic compound, an immunocompound such as an antibody or antibody active fragment, or a ligand such as a hormone, drug, antigen, or a hapten. The reduction of electrophoretic mobility achieved is directly proportional to the concentration of the polymer-linked affinity compound employed, and such reduction can comprise up to 100 percent for particular particles and cells. The present invention is advantageous in that electrophoretic separation can now be achieved for substances whose native surface charge structure had prevented them from being separated by normal electrophoretic means. Depending on the affinity component utilized, separation can be achieved on the basis of the specific/irreversible, specific/reversible, semi-specific/reversible, relatively nonspecific/reversible, or relatively nonspecific/irreversible ligand-substance interactions.

Plasma-mediated grafting of poly(ethylene glycol) on polyamide and polyester surfaces and evaluation of antifouling ability of modified substrates.

PubMed

Dong, Baiyan; Jiang, Hongquan; Manolache, Sorin; Wong, Amy C Lee; Denes, Ferencz S

2007-06-19

A simple cold plasma technique was developed to functionalize the surfaces of polyamide (PA) and polyester (PET) for the grafting of polyethylene glycol (PEG) with the aim of reducing biofilm formation. The surfaces of PA and PET were treated with silicon tetrachloride (SiCl4) plasma, and PEG was grafted onto plasma-functionalized substrates (PA-PEG, PET-PEG). Different molecular weights of PEG and grafting times were tested to obtain optimal surface coverage by PEG as monitored by electron spectroscopy for chemical analysis (ESCA). The presence of a predominant C-O peak on the PEG-modified substrates indicated that the grafting was successful. Data from hydroxyl group derivatization and water contact angle measurement also indicated the presence of PEG after grafting. The PEG-grafted PA and PET under optimal conditions had similar chemical composition and hydrophilicity; however, different morphology changes were observed after grafting. Both PA-PEG and PET-PEG surfaces developed under optimal plasma conditions showed about 96% reduction in biofilm formation by Listeria monocytogenes compared with that of the corresponding unmodified substrates. This plasma functionalization method provided an efficient way to graft PEG onto PA and PET surfaces. Because of the high reactivity of Si-Cl species, this method could potentially be applied to other polymeric materials.

Solvent decompositions and physical properties of decomposition compounds in Li-ion battery electrolytes studied by DFT calculations and molecular dynamics simulations.

PubMed

Tasaki, Ken

2005-02-24

The density functional theory (DFT) calculations have been performed for the reduction decompositions of solvents widely used in Li-ion secondary battery electrolytes, ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonates (DMC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC), including a typical electrolyte additive, vinylene carbonate (VC), at the level of B3LYP/6-311+G(2d,p), both in the gas phase and solution using the polarizable conductor calculation model. In the gas phase, the first electron reduction for the cyclic carbonates and for the linear carbonates is found to be exothermic and endothermic, respectively, while the second electron reduction is endothermic for all the compounds examined. On the contrary, in solution both first and second electron reductions are exothermic for all the compounds. Among the solvents and the additive examined, the likelihood of undergoing the first electron reduction in solution was found in the order of EC > PC > VC > DMC > EMC > DEC with EC being the most likely reduced. VC, on the other hand, is most likely to undergo the second electron reduction among the compounds, in the order of VC > EC > PC. Based on the results, the experimentally demonstrated effectiveness of VC as an excellent electrolyte additive was discussed. The bulk thermodynamic properties of two dilithium alkylene glycol dicarbonates, dilithium ethylene glycol dicarbonate (Li-EDC) and dilithium 1,2-propylene glycol dicarbonate (Li-PDC), as the major component of solid-electrolyte interface (SEI) films were also examined through molecular dynamics (MD) simulations in order to understand the stability of the SEI film. It was found that film produced from a decomposition of EC, modeled by Li-EDC, has a higher density, more cohesive energy, and less solubility to the solvent than the film produced from decomposition of PC, Li-PDC. Further, MD simulations of the interface between the decomposition compound and graphite suggested that Li-EDC has more favorable interactions with the graphite surface than Li-PDC. The difference in the SEI film stability and the behavior of Li-ion battery cycling among the solvents were discussed in terms of the molecular structures.

Biological production of organic compounds

DOEpatents

Yu, Jianping; Wang, Bo; Paddock, Troy; Carrieri, Damian; Maness, Pin-Ching; Seibert, Michael

2018-03-13

Methods of producing ethylene oxide and ethylene glycol are disclosed herein. Ethylene produced by cyanobacteria engineered to express ethylene-forming enzymes may be converted to ethylene oxide by bacteria engineered to express a monooxygenase enzyme. Ethylene oxide may be converted to ethylene glycol by exposure to an acidic solution. The methods may be performed in a bioreactor.

Measurement of diffusion coefficient of propylene glycol in skin tissue

NASA Astrophysics Data System (ADS)

Genin, Vadim D.; Bashkatov, Alexey N.; Genina, Elina A.; Tuchin, Valery V.

2015-03-01

Optical clearing of the rat skin under the action of propylene glycol was studied ex vivo. It was found that collimated transmittance of skin samples increased, whereas weight and thickness of the samples decreased during propylene glycol penetration in skin tissue. A mechanism of the optical clearing under the action of propylene glycol is discussed. Diffusion coefficient of propylene glycol in skin tissue ex vivo has been estimated as (1.35±0.95)×10-7 cm2/s with the taking into account of kinetics of both weight and thickness of skin samples. The presented results can be useful for enhancement of many methods of laser therapy and optical diagnostics of skin diseases and localization of subcutaneous neoplasms.

Method of preparing a high heating value fuel product

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

Somerville, R.; Fan, L.T.

1989-10-24

This patent describes a method of preparing a high heating value fuel product. The method comprising the steps of: blending a high heating value waste material with a cellulosic material; mixing an organic reagent to the blended mixture of the waste material and the cellulosic material, the organic reagent being a mixture having a 4-15 weight percent of a chemical selected from the group consisting of: triethylene, glycol, diethylene glycol, and glycerin propylene glycol; introducing a pozzolanic agent to the blended mixture for controlling the rate of solidification; and forming the blended mixture into a form suitable for handling. Alsomore » described is the same method with the mixture of the organic reagent further comprising: a 20-32 weight percent calcium chloride solution. Another method of preparing a fuel product is also described.« less

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.

Enhancement of the electrooxidation of ethanol on Pt-Sn-P/C catalysts prepared by chemical deposition process

NASA Astrophysics Data System (ADS)

Xue, Xinzhong; Ge, Junjie; Tian, Tian; Liu, Changpeng; Xing, Wei; Lu, Tianhong

In this paper, five Pt 3Sn 1/C catalysts have been prepared using three different methods. It was found that phosphorus deposited on the surface of carbon with Pt and Sn when sodium hypophosphite was used as reducing agent by optimization of synthetic conditions such as pH in the synthetic solution and temperature. The deposition of phosphorus should be effective on the size reduction and markedly reduces PtSn nanoparticle size, and raise electrochemical active surface (EAS) area of catalyst and improve the catalytic performance. TEM images show PtSnP nanoparticles are highly dispersed on the carbon surface with average diameters of 2 nm. The optimum composition is Pt 3Sn 1P 2/C (note PtSn/C-3) catalyst in my work. With this composition, it shows very high activity for the electrooxidation of ethanol and exhibit enhanced performance compared with other two Pt 3Sn 1/C catalysts that prepared using ethylene glycol reduction method (note PtSn/C-EG) and borohydride reduction method (note PtSn/-B). The maximum power densities of direct ethanol fuel cell (DEFC) were 61 mW cm -2 that is 150 and 170% higher than that of the PtSn/C-EG and PtSn/C-B catalyst.

Experimental Investigation of Heat Transfer Characteristics of Automobile Radiator using TiO2-Nanofluid Coolant

NASA Astrophysics Data System (ADS)

Salamon, V.; Senthil kumar, D.; Thirumalini, S.

2017-08-01

The use of nanoparticle dispersed coolants in automobile radiators improves the heat transfer rate and facilitates overall reduction in size of the radiators. In this study, the heat transfer characteristics of water/propylene glycol based TiO2 nanofluid was analyzed experimentally and compared with pure water and water/propylene glycol mixture. Two different concentrations of nanofluids were prepared by adding 0.1 vol. % and 0.3 vol. % of TiO2 nanoparticles into water/propylene glycol mixture (70:30). The experiments were conducted by varying the coolant flow rate between 3 to 6 lit/min for various coolant temperatures (50°C, 60°C, 70°C, and 80°C) to understand the effect of coolant flow rate on heat transfer. The results showed that the Nusselt number of the nanofluid coolant increases with increase in flow rate. At low inlet coolant temperature the water/propylene glycol mixture showed higher heat transfer rate when compared with nanofluid coolant. However at higher operating temperature and higher coolant flow rate, 0.3 vol. % of TiO2 nanofluid enhances the heat transfer rate by 8.5% when compared to base fluids.

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.

Analysis of eight glycols in serum using LC-ESI-MS-MS.

PubMed

Imbert, Laurent; Saussereau, Elodie; Lacroix, Christian

2014-01-01

A liquid chromatography coupled with electrospray tandem mass spectrometry method was developed for the analysis of ethylene glycol, diethylene glycol, triethylene glycol, 1,4-butanediol, 1,2-butanediol, 2,3-butanediol, 1,2-propanediol and 1,3-propanediol, in serum after a Schotten-Baumann derivatization by benzoyl chloride. Usual validation parameters were tested: linearity, repeatability and intermediate precision, limits of detection and quantification, carry over and ion suppression. Limits of detection were between 0.18 and 1.1 mg/L, and limits of quantification were between 0.4 and 2.3 mg/L. Separation of isomers was possible either chromatographically or by selecting specific multiple reaction monitoring transitions. This method could be a useful tool in case of suspected intoxication with antifreeze agents, solvents, dietary supplements or some medical drug compounds. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Implementation of flowsheet change to minimize hydrogen and ammonia generation during chemical processing of high level waste in the Defense Waste Processing Facility

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

Lambert, Dan P.; Woodham, Wesley H.; Williams, Matthew S.

Testing was completed to develop a chemical processing flowsheet for the Defense Waste Processing Facility (DWPF), designed to vitrify and stabilize high level radioactive waste. DWPF processing uses a reducing acid (formic acid) and an oxidizing acid (nitric acid) to rheologically thin the slurry and complete the necessary acid base and reduction reactions (primarily mercury and manganese). Formic acid reduces mercuric oxide to elemental mercury, allowing the mercury to be removed during the boiling phase of processing through steam stripping. In runs with active catalysts, formic acid can decompose to hydrogen and nitrate can be reduced to ammonia, both flammablemore » gases, due to rhodium and ruthenium catalysis. Replacement of formic acid with glycolic acid eliminates the generation of rhodium- and ruthenium-catalyzed hydrogen and ammonia. In addition, mercury reduction is still effective with glycolic acid. Hydrogen, ammonia and mercury are discussed in the body of the report. Ten abbreviated tests were completed to develop the operating window for implementation of the flowsheet and determine the impact of changes in acid stoichiometry and the blend of nitric and glycolic acid as it impacts various processing variables over a wide processing region. Three full-length 4-L lab-scale simulations demonstrated the viability of the flowsheet under planned operating conditions. The flowsheet is planned for implementation in early 2017.« less

Development and evaluation of novel antihypertensive orodispersible tablets.

PubMed

Khan, Hafeez Ullah; Hanif, Muhammad; Sarfraz, Rai M; Maheen, Safirah; Afzal, Samina; Sher, Muhammad; Afzal, Khurram; Mahmood, Asif; Shamim, Ayesha

2017-09-01

Objective of present study was to enhance patient compliance in pediatrics and geriatrics patients of Hypertension. To achieve this target, innovative orodispersible tablets of atenolol and atorvastatin was developed to produce instant action by rapidly disintegrating into oral cavity. Three different techniques like direct compression, effervescent and sublimation methods were used to prepare these tablets (Five batches of tablets by each method) by using two superdisintegrants like Sodium starch glycolate and pregelatinized starch alone and in combination. Pre-formulation studies including rheological analysis (Bulk density, tapped density, Angle of repose, Carr's compressibility index, Hausner's ratio), compatibility studies such as Fourier transform infrared spectrophotometry (FTIR) and Differential scanning colorimetry (DSC), Post-compression and stability studies were also performed. Finally, results were statistically evaluated by the applying one way ANOVA test and mean. It was concluded that the formulation F8 containing Sodium starch glycolate 2% and pregelatinized starch 6% found best regarding disintegration time, wetting volume, wetting time, release studies etc. The order in which drug release was quicker is Pregelatinized starch plus Sodium starch glycolate > Pregelatinized starch > Sodium starch glycolate (primojel). It was concluded that sublimation method was the best among three methods used for orodispersible tablets formulations.

Experimental and analytical investigation of a freezing point depressant fluid ice protection system. M.S. Thesis. Final Report

NASA Technical Reports Server (NTRS)

Albright, A. E.

1984-01-01

A glycol-exuding porous leading edge ice protection system was tested in the NASA Icing Research Tunnel. Stainless steel mesh, laser drilled titanium, and composite panels were tested on two general aviation wing sections. Two different glycol-water solutions were evaluated. Minimum glycol flow rates required for anti-icing were obtained as a function of angle of attack, liquid water content, volume median drop diameter, temperature, and velocity. Ice accretions formed after five minutes of icing were shed in three minutes or less using a glycol fluid flow equal to the anti-ice flow rate. Two methods of predicting anti-ice flow rates are presented and compared with a large experimental data base of anti-ice flow rates over a wide range of icing conditions. The first method presented in the ADS-4 document typically predicts flow rates lower than the experimental flow rates. The second method, originally published in 1983, typically predicts flow rates up to 25 percent higher than the experimental flow rates. This method proved to be more consistent between wing-panel configurations. Significant correlation coefficients between the predicted flow rates and the experimental flow rates ranged from .867 to .947.

Effect of compositions in nanostructured lipid carriers (NLC) on skin hydration and occlusion

PubMed Central

Loo, CH; Basri, M; Ismail, R; Lau, HLN; Tejo, BA; Kanthimathi, MS; Hassan, HA; Choo, YM

2013-01-01

Purpose To study the effects of varying lipid concentrations, lipid and oil ratio, and the addition of propylene glycol and lecithin on the long-term physical stability of nanostructured lipid nanocarriers (NLC), skin hydration, and transepidermal water loss. Methods The various NLC formulations (A1–A5) were prepared and their particle size, zeta potential, viscosity, and stability were analyzed. The formulations were applied on the forearms of the 20 female volunteers (one forearm of each volunteer was left untreated as a control). The subjects stayed for 30 minutes in a conditioned room with their forearms uncovered to let the skin adapt to the temperature (22°C ± 2°C) and humidity (50% ± 2%) of the room. Skin hydration and skin occlusion were recorded at day one (before treatment) and day seven (after treatment). Three measurements for skin hydration and skin occlusion were performed in each testing area. Results NLC formulations with the highest lipid concentration, highest solid lipid concentration, and additional propylene glycol (formulations A1, A2, and A5) showed higher physical stability than other formulations. The addition of propylene glycol into an NLC system helped to reduce the particle size of the NLC and enhanced its long-term physical stability. All the NLC formulations were found to significantly increase skin hydration compared to the untreated controls within 7 days. All NLC formulations exhibited occlusive properties as they reduced the transepidermal water loss within 7 days. This effect was more pronounced with the addition of propylene glycol or lecithin into an NLC formulation, whereby at least 60% reduction in transepidermal water loss was observed. Conclusion NLCs with high lipid content, solid lipid content, phospholipid, and lecithin are a highly effective cosmetic delivery system for cosmetic topical applications that are designed to boost skin hydration. PMID:23293516

Randomized clinical efficacy of superficial peeling with 85% lactic acid versus 70% glycolic acid*

PubMed Central

Prestes, Paula Souza; de Oliveira, Márcia Motta Maia; Leonardi, Gislaine Ricci

2013-01-01

BACKGROUND: Peeling is a procedure which aims to accelerate the process of skin exfoliation. OBJECTIVES Development of formulations containing lactic acid at 85% or glycolic acid at 70% and the evaluation of these formulations on clinical efficacy in reduction of fine wrinkles. METHODS Preliminary stability tests were carried out and an in vivo study was performed with three groups with 9 representatives each. One was the control group, which used only sunscreen; another one used lactic acid+sunscreen, and the last group used acid glycolic+sunscreen. Clinical efficacy was assessed with a CCD color microscope, through the digitization of images before and after treatment. The applications were carried out by a dermatologist, once a mont h every 30 days, during 3 months. The area with wrinkles was calculated by planimetry point counting, in accordance with Mandarin-de-Lacerda. RESULTS The formulations were stable in the visual and Ph evaluation. There was no improvement in the control group; for lactic acid, there was significant improvement after the second peeling application on the outer lateral area of the right eye and after the third application on the outer lateral area of the left eye. For the glycolic acid group, there was significant improvement in the outer lateral area of the left eye after the first application, and of the right eye region, after three applications. The formulations used must be kept under refrigeration and should be manipulated every 30 days. CONCLUSIONS Both peelings were effective in reducing fine wrinkles of the outer lateral eye area after three applications (p≤0.05%). It was observed that peeling efficacy in the external-lateral region of one eye might be different compared with that in skin of the external-lateral region of the other eye, relative to the speed of skin improvement. PMID:24474097

A cost effective method of meeting emission requirements from a 50 MMscfd glycol dehydrator

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

Gearhart, L.E.

1998-12-31

The removal of volatile organic compounds (VOC) and benzene, toluene, ethylbenzene, xylene (BTEX) from glycol dehydration systems does not require costly equipment or elaborate controls. This paper will describe the design and installation of a 10 equivalent try glycol dehydration unit for field gas dehydration. The absorber design minimizes the absorption of VOC and BTEX by requiring 1.0 to 1.5 gallons of glycol per pound of water removed. Glycol unit VOC emissions are effectively controlled without installing vent gas condensers which require disposal of the waste condensate. The emission control system on this unit is simple to operate, meets emissionmore » standards and the dehydrator design achieves pipeline sales gas specifications at a reasonable cost. The system reduces the VOC and BTEX by adding a stripper on the glycol going to the reboiler. A 50 MMscfd dehydrator was installed in December 1995 and the results of an emission test done in April 1997 are presented in this paper.« less

Ethylene glycol emissions from on-road vehicles: implications for aqueous phase secondary organic aerosol formation

NASA Astrophysics Data System (ADS)

Wood, E. C.; Knighton, W. B.; Fortner, E.; Herndon, S. C.; Onasch, T. B.; Franklin, J.; Harley, R. A.; Gentner, D. R.; Goldstein, A. H.

2012-12-01

Ethylene glycol (HOCH2CH2OH), used as an engine coolant for most on-road vehicles, is an intermediate volatility organic compound (IVOC) with a high Henry's Law Coefficient (kH > 10,000 M atm-1) . Oxidation of ethylene glycol, especially in the atmospheric aqueous phase (clouds, fog, wet aerosol), can lead to the formation of glycolaldehyde, oxalic acid, and ultimately secondary organic aerosol. We present measurements of unexpectedly high ethylene glycol emissions in the Caldecott Tunnel near San Francisco (Summer 2010) and the Washburn Tunnel near Houston (Spring 2009). Ethylene glycol was detected using a proton-transfer reaction mass spectrometer (PTR-MS) at m/z = 45, which is usually interpreted as acetaldehyde. Although not necessarily a tailpipe emission, effective fuel-based emission factors are calculated using the carbon balance method and range from 50 to 400 mg ethylene glycol per kg fuel. Total US and global emissions are estimated using these emission factors and fuel consumption rates and are compared to previous model estimates of ethylene glycol emissions (e.g., the Regional Atmospheric Chemistry Model). Compared to biogenically emitted isoprene, ethylene glycol is likely a minor source of glycolaldehyde globally, but may contribute significantly to glycolaldehyde, oxalate and SOA formation in areas dominated by urban emissions.

Design of enzyme-mediated controlled release systems based on silica mesoporous supports capped with ester-glycol groups.

PubMed

Agostini, Alessandro; Mondragón, Laura; Pascual, Lluis; Aznar, Elena; Coll, Carmen; Martínez-Máñez, Ramón; Sancenón, Félix; Soto, Juan; Marcos, M Dolores; Amorós, Pedro; Costero, Ana M; Parra, Margarita; Gil, Salvador

2012-10-16

An ethylene glycol-capped hybrid material for the controlled release of molecules in the presence of esterase enzyme has been prepared. The final organic-inorganic hybrid solid S1 was synthesized by a two-step procedure. In the first step, the pores of an inorganic MCM-41 support (in the form of nanoparticles) were loaded with [Ru(bipy)(3)]Cl(2) complex, and then, in the second step, the pore outlets were functionalized with ester glycol moieties that acted as molecular caps. In the absence of an enzyme, release of the complex from aqueous suspensions of S1 at pH 8.0 is inhibited due to the steric hindrance imposed by the bulky ester glycol moieties. Upon addition of esterase enzyme, delivery of the ruthenium complex was observed due to enzymatic hydrolysis of the ester bond in the anchored ester glycol derivative, inducing the release of oligo(ethylene glycol) fragments. Hydrolysis of the ester bond results in size reduction of the appended group, therefore allowing delivery of the entrapped cargo. The S1 nanoparticles were not toxic for cells, as demonstrated by cell viability assays with HeLa and MCF-7 cell lines, and were found to be associated with lysosomes, as shown by confocal microscopy. However, when S1 nanoparticles were filled with the cytotoxic drug camptothecin (S1-CPT), S1-CPT-treated cells undergo cell death as a result of S1-CPT cell internalization and subsequent cellular enzyme-mediated hydrolysis and aperture of the molecular gate that induced the release of the camptothecin cargo. These findings point to a possible therapeutic application of these nanoparticles.

Selective catalytic two-step process for ethylene glycol from carbon monoxide

PubMed Central

Dong, Kaiwu; Elangovan, Saravanakumar; Sang, Rui; Spannenberg, Anke; Jackstell, Ralf; Junge, Kathrin; Li, Yuehui; Beller, Matthias

2016-01-01

Upgrading C1 chemicals (for example, CO, CO/H2, MeOH and CO2) with C–C bond formation is essential for the synthesis of bulk chemicals. In general, these industrially important processes (for example, Fischer Tropsch) proceed at drastic reaction conditions (>250 °C; high pressure) and suffer from low selectivity, which makes high capital investment necessary and requires additional purifications. Here, a different strategy for the preparation of ethylene glycol (EG) via initial oxidative coupling and subsequent reduction is presented. Separating coupling and reduction steps allows for a completely selective formation of EG (99%) from CO. This two-step catalytic procedure makes use of a Pd-catalysed oxycarbonylation of amines to oxamides at room temperature (RT) and subsequent Ru- or Fe-catalysed hydrogenation to EG. Notably, in the first step the required amines can be efficiently reused. The presented stepwise oxamide-mediated coupling provides the basis for a new strategy for selective upgrading of C1 chemicals. PMID:27377550

Thermal conductivity enhancement of nano-silver particles dispersed ethylene glycol based nanofluids

NASA Astrophysics Data System (ADS)

Khamliche, Touria; Khamlich, Saleh; Doyle, Terry B.; Makinde, Daniel; Maaza, Malik

2018-03-01

This contribution reports on the thermal conductivity enhancement of nano-silver particles (nAgPs) based nanofluids with various nAgPs’ shapes in view of their potential application in concentrated solar power systems. More accurately, the thermal conductivity behaviour of suspensions of nAgPs dispersed ethylene glycol (nAgPs:EG), prepared by a simple and cost effective chemical synthesis method, is compared with a theoretical prediction. The effect of aging time on the shape of the dispersed nAgPs was clearly observed by the structural, optical and morphological analysis. Spherically shaped and Ag nanowires (AgNWs) with high yields were observed when the nAgPs was aged for 1 and 5 h, respectively. The observed AgNWs showed high aspect ratio (≥200) when EG and polyvinylpyrrolidone (PVP) were used as reductant and structure-directing agents. The thermal conductivity measurements on nAgPs:EG nanofuids with different volume fractions of nAgPs were conducted in a temperature range 25 < T < 50 °C using a guarded hot plate (GHP) method. The thermal conductivity manifested a generally monotonic increase with temperature and an approximately linear relationship with the volume fraction of the nAgPs. Particularly, an enhancement of up to 23% was observed when the nanofluid was aged for 5 h and AgNWs were dominant.

In vitro antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis in root canals

PubMed Central

VALERA, Marcia Carneiro; MAEKAWA, Lilian Eiko; de OLIVEIRA, Luciane Dias; JORGE, Antonio Olavo Cardoso; SHYGEI, Érika; CARVALHO, Cláudio Antonio Talge

2013-01-01

Objective: The aim of this study was to evaluate the antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis inoculated in root canals. Material and Methods: Seventy-two human tooth roots were contaminated with C. albicans and E. faecalis for 21 days. The groups were divided according to the auxiliary chemical substance into: G1) 2.5% sodium hypochlorite (NaOCl), G2) 2% chlorhexidine gel (CHX), G3) castor oil, G4) glycolic Aloe vera extract, G5) glycolic ginger extract, and G6) sterile saline (control). The samples of the root canal were collected at different intervals: confirmation collection, at 21 days after contamination; 1st collection, after instrumentation; and 2nd collection, seven days after instrumentation. Microbiological samples were grown in culture medium and incubated at 37º C for 48 hours. Results: The results were submitted to the Kruskal-Wallis and Dunn (5%) statistical tests. NaOCl and CHX completely eliminated the microorganisms of the root canals. Castor oil and ginger significantly reduced the number of CFU of the tested bacteria. Reduction of CFU/mL at the 1st and 2nd collections for groups G1, G2, G3 and G4 was greater in comparison to groups G5 and G6. Conclusion: It was concluded that 2.5% sodium hypochlorite and 2% chlorhexidine gel were more effective in eliminating C. albicans and E. faecalis, followed by the castor oil and glycolic ginger extract. The Aloe vera extract showed no antimicrobial activity. PMID:23739849

Rapid Diagnosis of Ethylene Glycol Poisoning by Urine Microscopy.

PubMed

Sheta, Hussam Mahmoud; Al-Najami, Issam; Christensen, Heidi Dahl; Madsen, Jonna Skov

2018-06-14

BACKGROUND Ethylene glycol poisoning remains an important presentation to Emergency Departments. Quick diagnosis and treatment are essential to prevent renal failure and life-threating complications. CASE REPORT In this case report, we present a patient who was admitted unconscious to the hospital. Ethylene glycol poisoning was immediately suspected, because the patient had previously been hospitalized with similar symptoms after intake of antifreeze coolant. A urine sample was sent for microscopy and showed multiple calcium oxalate monohydrate (COM) crystals, which supported the clinical suspicion of ethylene glycol poisoning. The patient was treated with continuous intravenous ethyl alcohol infusion and hemodialysis. Two days after admission, the patient was awake and in clinical recovery. CONCLUSIONS Demonstration of COM crystals using microscopy of a urine sample adds valuable information supporting the clinical suspicion of ethylene glycol poisoning, and may serve as an easy, quick, and cheap method that can be performed in any emergency setting.

Evaluation of the matrix effect on gas chromatography--mass spectrometry with carrier gas containing ethylene glycol as an analyte protectant.

PubMed

Fujiyoshi, Tomoharu; Ikami, Takahito; Sato, Takashi; Kikukawa, Koji; Kobayashi, Masato; Ito, Hiroshi; Yamamoto, Atsushi

2016-02-19

The consequences of matrix effects in GC are a major issue of concern in pesticide residue analysis. The aim of this study was to evaluate the applicability of an analyte protectant generator in pesticide residue analysis using a GC-MS system. The technique is based on continuous introduction of ethylene glycol into the carrier gas. Ethylene glycol as an analyte protectant effectively compensated the matrix effects in agricultural product extracts. All peak intensities were increased by this technique without affecting the GC-MS performance. Calibration curves for ethylene glycol in the GC-MS system with various degrees of pollution were compared and similar response enhancements were observed. This result suggests a convenient multi-residue GC-MS method using an analyte protectant generator instead of the conventional compensation method for matrix-induced response enhancement adding the mixture of analyte protectants into both neat and sample solutions. Copyright © 2016 Elsevier B.V. All rights reserved.

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.

APPLICATION OF VARIOUS POLYMERS AND POLYMERS BASED TECHNIQUES USED TO IMPROVE SOLUBILITY OF POORLY WATER SOLUBLE DRUGS: A REVIEW.

PubMed

Muhammad Sarfraz, Rai; Bashir, Sajid; Mahmood, Asif; Ahsan, Haseeb; Riaz, Humayun; Raza, Hina; Rashid, Zermina; Atif Raza, Syed; Asad Abrar, Muhammad; Abbas, Khawar; Yasmeen, Tahira

2017-03-01

Solubility is concerned with solute and solvent to form a homogenous mixture. If solubility of a drug is low, then usually it is difficult to achieve desired therapeutic level of drug. Most of the newly developed entities have solubility problems and encounter difficulty in dissolution. Basic aim of solubility enhancement is to achieve desired therapeutic'level of drug to produce required pharmacological response. Different techniques are being used to enhance the solubility of water insoluble drugs. These techniques include particle size reduction, spray drying, kneading method, solvent evaporation method, salt formation, microemulsions, co-solven- cy, hydrosols, prodrug approach, supercritical fluid process, hydrogel micro particles etc. Selection of solubility improving method depends on drug properties, site of absorption, and required dosage form characteristics. Variety of polymers are also used to enhance solubility of these drugs like polyethylene glycol 300, polyvinyl pyrrolidone, chitosan, β-cyclodextrins etc.

Synthesis and characterization of silver-copper core-shell nanoparticles using polyol method for antimicrobial agent

NASA Astrophysics Data System (ADS)

Hikmah, N.; Idrus, N. F.; Jai, J.; Hadi, A.

2016-06-01

Silver and copper nanoparticles are well-known as the good antimicrobial agent. The nano-size of particles influences in enhancing the antimicrobial activity. This paper discusses the effect of molarity on the microstructure and morphology of silver-copper core-shell nanoparticles prepared by a polyol method. In this study, silver-copper nanoparticles are synthesized through the green approach of polyol method using ethylene glycol (EG) as green solvent and reductant, and polyoxyethylene-(80)-sorbitan monooleate (Tween 80) as a nontoxic stabilizer. The phase and morphology of silver-copper nanoparticles are characterized by X-ray diffraction (XRD) and Field emission scanning electron microscope (FESEM) and Transmission electron microscope (TEM). The results XRD confirm the pure crystalline of silver and copper nanoparticles with face-centered cubic (FCC) structure. FESEM and TEM analysis confirm the existence of Ag and Cu nanoparticles in core-shell shape.

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.

Confocal Raman microscopy and multivariate statistical analysis for determination of different penetration abilities of caffeine and propylene glycol applied simultaneously in a mixture on porcine skin ex vivo.

PubMed

Mujica Ascencio, Saul; Choe, ChunSik; Meinke, Martina C; Müller, Rainer H; Maksimov, George V; Wigger-Alberti, Walter; Lademann, Juergen; Darvin, Maxim E

2016-07-01

Propylene glycol is one of the known substances added in cosmetic formulations as a penetration enhancer. Recently, nanocrystals have been employed also to increase the skin penetration of active components. Caffeine is a component with many applications and its penetration into the epidermis is controversially discussed in the literature. In the present study, the penetration ability of two components - caffeine nanocrystals and propylene glycol, applied topically on porcine ear skin in the form of a gel, was investigated ex vivo using two confocal Raman microscopes operated at different excitation wavelengths (785nm and 633nm). Several depth profiles were acquired in the fingerprint region and different spectral ranges, i.e., 526-600cm(-1) and 810-880cm(-1) were chosen for independent analysis of caffeine and propylene glycol penetration into the skin, respectively. Multivariate statistical methods such as principal component analysis (PCA) and linear discriminant analysis (LDA) combined with Student's t-test were employed to calculate the maximum penetration depths of each substance (caffeine and propylene glycol). The results show that propylene glycol penetrates significantly deeper than caffeine (20.7-22.0μm versus 12.3-13.0μm) without any penetration enhancement effect on caffeine. The results confirm that different substances, even if applied onto the skin as a mixture, can penetrate differently. The penetration depths of caffeine and propylene glycol obtained using two different confocal Raman microscopes are comparable showing that both types of microscopes are well suited for such investigations and that multivariate statistical PCA-LDA methods combined with Student's t-test are very useful for analyzing the penetration of different substances into the skin. Copyright © 2016 Elsevier B.V. All rights reserved.

Yields of damage to C4' deoxyribose and to pyrimidines in pUC18 by the direct effect of ionizing radiation.

PubMed

Peoples, Anita R; Lee, Jane; Weinfeld, Michael; Milligan, Jamie R; Bernhard, William A

2012-07-01

Our mechanistic understanding of damage formation in DNA by the direct effect relies heavily on what is known of free radical intermediates studied by EPR spectroscopy. Bridging this information to stable product formation requires methods with comparable sensitivities, a criterion met by the (32)P-post-labeling assay developed by Weinfeld and Soderlind, [Weinfeld,M. and Soderlind,K.-J.M. (1991) (32)P-Postlabeling detection of radiation-induced DNA damage: identification and estimation of thymine glycols and phosphoglycolate termini. Biochemistry, 30, 1091-1097] which when applied to the indirect effect, detected phosphoglycolate (pg) and thymine glycol (Tg). Here we applied this assay to the direct effect, measuring product yields in pUC18 films with hydration levels (Γ) of 2.5, 16 or 23 waters per nucleotide and X-irradiated at either 4 K or room temperature (RT). The yields of pg [G(pg)] for Γ ≈ 2.5 were 2.8 ± 0.2 nmol/J (RT) and 0.2 ± 0.3 nmol/J (4 K), which is evidence that the C4' radical contributes little to the total deoxyribose damage via the direct effect. The yield of detectable base damage [G(B*)] at Γ ≈ 2.5 was found to be 30.2 ± 1.0 nmol/J (RT) and 12.9 ± 0.7 nmol/J (4 K). While the base damage called B*, could be due to either oxidation or reduction, we argue that two reduction products, 5,6-dihydrouracil and 5,6-dihydrothymine, are the most likely candidates.

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.

IF-WS{sub 2} nanoparticles size design and synthesis via chemical reduction

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

Ghoreishi, S.M., E-mail: ghoreshi@cc.iut.ac.ir; Meshkat, S.S.; Dadkhah, A.A.

2010-05-15

An innovative synthesis of inorganic fullerene-like disulfide tungsten (IF-WS{sub 2}) nanoparticles was developed using a chemical reduction reaction in a horizontal quartz reactor. In this process, first tungsten trisulfide (WS{sub 3}) was formed via a chemical reaction of tetra thiotungstate ammonium ((NH{sub 4}){sub 2}WS{sub 4}), polyethylene glycol (PEG), and hydrochloric acid (HCl) at ambient temperature and pressure. Subsequently, WS{sub 3} was reacted with hydrogen (H{sub 2}) at high temperature (1173-1373 K) in a quartz tube. The produced WS{sub 2} nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDAX), and transmission electron microscopy (TEM). Themore » characterization results indicated that the high-purity (100%) IF-WS{sub 2} nanoparticles were produced. Moreover, addition of surfactant (PEG) and higher operating temperature (1173-1373 K) decreased the particles agglomeration, and consequently led to the reduction of average diameter of WS{sub 2} particles in the range of 50-78 nm. The developed method is simple, environmentally compatible, and cost-effective in contrast to the conventional techniques.« less

Separation of oxalate, formate and glycolate in human body fluid samples by capillary electrophoresis with contactless conductometric detection.

PubMed

Kubáň, Petr; Ďurč, Pavol; Bittová, Miroslava; Foret, František

2014-01-17

A new method for rapid determination of toxic metabolites after methanol and ethylene glycol intoxication - oxalate, formate and glycolate in various body fluid samples (blood serum, saliva, urine, exhaled breath condensate) by capillary electrophoresis with contactless conductometric detection was developed. A selective separation of the three target analytes from other constituents present in the analyzed biological matrices was achieved in less than 6min in a fused silica capillary of 25μm I.D. using an electrolyte comprising 50mM l-histidine and 50mM 2-(N-morpholino)ethanesulfonic acid at pH 6.1. The only sample preparation was dilution with deionized water. The limits of detection were 0.4, 0.6 and 1.3μM and limits of quantitation 1.3, 1.9 and 4.2μM for oxalate, formate and glycolate, respectively. The method provides a simple and rapid diagnostic test in suspected intoxication and is able to distinguish the ingested liquid, based on its metabolite trace. The method presents a fast screening tool that can be applicable in clinical practice. Copyright © 2013 Elsevier B.V. All rights reserved.

Photoelectrochemical cell for simultaneous electricity generation and heavy metals recovery from wastewater.

PubMed

Wang, Dawei; Li, Yi; Li Puma, Gianluca; Lianos, Panagiotis; Wang, Chao; Wang, Peifang

2017-02-05

The feasibility of simultaneous recovery of heavy metals from wastewater (e.g., acid mining and electroplating) and production of electricity is demonstrated in a novel photoelectrochemical cell (PEC). The photoanode of the cell bears a nanoparticulate titania (TiO 2 ) film capped with the block copolymer [poly(ethylene glycol)-b-poly(propylene glycol)-b-poly(ethylene glycol)] hole scavenger, which consumed photogenerated holes, while the photogenerated electrons transferred to a copper cathode reducing dissolved metal ions and produced electricity. Dissolved silver Ag + , copper Cu 2+ , hexavalent chromium as dichromate Cr 2 O 7 2- and lead Pb 2+ ions in a mixture (0.2mM each) were removed at different rates, according to their reduction potentials. Reduced Ag + , Cu 2+ and Pb 2+ ions produced metal deposits on the cathode electrode which were mechanically recovered, while Cr 2 O 7 2- reduced to the less toxic Cr 3+ in solution. The cell produced a current density J sc of 0.23mA/cm 2 , an open circuit voltage V oc of 0.63V and a maximum power density of 0.084mW/cm 2 . A satisfactory performance of this PEC for the treatment of lead-acid battery wastewater was observed. The cathodic reduction of heavy metals was limited by the rate of electron-hole generation at the photoanode. The PEC performance decreased by 30% after 9 consecutive runs, caused by the photoanode progressive degradation. Copyright © 2016 Elsevier B.V. All rights reserved.

40 CFR 63.1282 - Test methods, compliance procedures, and compliance demonstrations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... compliance demonstrations. (a) Determination of glycol dehydration unit flowrate, benzene emissions, or BTEX... dehydration unit natural gas flowrate, benzene emissions, or BTEX emissions. (1) The determination of actual flowrate of natural gas to a glycol dehydration unit shall be made using the procedures of either paragraph...

40 CFR 63.1282 - Test methods, compliance procedures, and compliance demonstrations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... compliance demonstrations. (a) Determination of glycol dehydration unit flowrate, benzene emissions, or BTEX... dehydration unit natural gas flowrate, benzene emissions, or BTEX emissions. (1) The determination of actual flowrate of natural gas to a glycol dehydration unit shall be made using the procedures of either paragraph...

Construction of poly(lactic-co-glycolic acid)/ZnO nanorods/Ag nanoparticles hybrid coating on Ti implants for enhanced antibacterial activity and biocompatibility.

PubMed

Xiang, Yiming; Li, Jun; Liu, Xiangmei; Cui, Zhenduo; Yang, Xianjin; Yeung, K W K; Pan, Haobo; Wu, Shuilin

2017-10-01

Poly(lactic-co-glycolic acid)/Ag/ZnO nanorods coating were successfully prepared on the surface of Ti metallic implants using a hydrothermal method and subsequent spin-coating of mixtures of poly(lactic-co-glycolic acid) and silver nanoparticles. The poly(lactic-co-glycolic acid)/Ag/ZnO nanorods coating exhibited excellent antibacterial efficacy of over 96% against both Staphylococcus aureus and Escherichia coli when the initial content of Ag nanoparticles was over 3wt%. In addition, the release of both silver and zinc could last for over a hundred days due to the enwrapping of poly(lactic-co-glycolic acid). Proliferation of mouse calvarial cells exhibited minimal cytotoxicity on the poly(lactic-co-glycolic acid)/Ag/ZnO coating with an initial content of Ag nanoparticles of 1wt% and 3wt%, while it inhibited cell proliferation once this value was increased to 6wt%. The results revealed that this poly(lactic-co-glycolic acid)/Ag/ZnO composite could provide a long-lasting antibacterial approach and good cytocompatibility, thus exhibiting considerable potential for biomedical application in orthopedic and dental implants with excellent self-antibacterial activity and good biocompatibility. Copyright © 2017 Elsevier B.V. All rights reserved.

Hydrogenolysis of 5-carbon sugars, sugar alcohols, and methods of making propylene glycol

DOEpatents

Werpy, Todd A [West Richland, WA; Zacher, Alan H [Kennewick, WA; Miller, Dennis J [Okemos, MI

2006-05-02

Methods and compositions for reactions of hydrogen over a Re-containing catalyst with compositions containing a 5-carbon sugar, sugar alcohol, or lactic acid are described. It has been surprisingly discovered that reaction with hydrogen over a Re-containing multimetallic catalyst resulted in superior conversion and selectivity to desired products such as propylene glycol. A process for the synthesis of PG from lactate or lactic acid is also described.

Detection of diethylene glycol adulteration in propylene glycol--method validation through a multi-instrument collaborative study.

PubMed

Li, Xiang; Arzhantsev, Sergey; Kauffman, John F; Spencer, John A

2011-04-05

Four portable NIR instruments from the same manufacturer that were nominally identical were programmed with a PLS model for the detection of diethylene glycol (DEG) contamination in propylene glycol (PG)-water mixtures. The model was developed on one spectrometer and used on other units after a calibration transfer procedure that used piecewise direct standardization. Although quantitative results were produced, in practice the instrument interface was programmed to report in Pass/Fail mode. The Pass/Fail determinations were made within 10s and were based on a threshold that passed a blank sample with 95% confidence. The detection limit was then established as the concentration at which a sample would fail with 95% confidence. For a 1% DEG threshold one false negative (Type II) and eight false positive (Type I) errors were found in over 500 samples measured. A representative test set produced standard errors of less than 2%. Since the range of diethylene glycol for economically motivated adulteration (EMA) is expected to be above 1%, the sensitivity of field calibrated portable NIR instruments is sufficient to rapidly screen out potentially problematic materials. Following method development, the instruments were shipped to different sites around the country for a collaborative study with a fixed protocol to be carried out by different analysts. NIR spectra of replicate sets of calibration transfer, system suitability and test samples were all processed with the same chemometric model on multiple instruments to determine the overall analytical precision of the method. The combined results collected for all participants were statistically analyzed to determine a limit of detection (2.0% DEG) and limit of quantitation (6.5%) that can be expected for a method distributed to multiple field laboratories. Published by Elsevier B.V.

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.

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

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.

Comparative study of 15% TCA peel versus 35% glycolic acid peel for the treatment of melasma

PubMed Central

Puri, Neerja

2012-01-01

Background: Chemical peels are the mainstay of a cosmetic practitioner's armamentarium because they can be used to treat some skin disorders and can provide aesthetic benefit. Objectives: To compare 15% TCA peel and 35% glycolic acid peel for the treatment of melasma. Material and Methods: We selected 30 participants of melasma aged between 20 and 50 years from the dermatology outpatient department and treated equal numbers with 15% TCA and 35% glycolic acid. Results: Subjective response as graded by the patient showed good or very good response in 70% participants in the glycolic acid group and 64% in the TCA group. Conclusions: There was statistically insignificant difference in the efficacy between the two groups for the treatment of melasma. PMID:23130283

UV stabilization of wood by nano metal oxides dispersed in propylene glycol.

PubMed

Nair, Sreeja; Nagarajappa, Giridhar B; Pandey, Krishna K

2018-06-01

Nanoparticles of some of the metal oxides are known to have high UV protective efficiency. The UV filtering efficiency of nanoparticles invariably depends on their size and stability in the dispersion. In the present work, a stable dispersion of nanoparticles of three metal oxides, zinc oxide (ZnO), cerium oxide (CeO 2 ) and titanium dioxide (TiO 2 ), was prepared in propylene glycol (PG) using ultrasonication. The method is easy and useful as no additional surfactant or dispersant is needed. The particle size and its distribution was confirmed by Scanning Electron Microscopy and Dynamic Light Scattering. The stability of dispersion was assessed by UV-visible absorption spectroscopy. The UV stability of wood surfaces of Wrightia tinctoria coated with nanodispersions of ZnO, CeO 2 and TiO 2 was evaluated under laboratory conditions in an accelerated weathering tester. Changes in the colour and FTIR spectra of exposed specimens were measured periodically. Rapid colour darkening (yellowing) was observed in uncoated and PG coated specimens. In contrast, nanodispersion coated specimens prevented photo-yellowing considerably with significant reduction in colour changes examined by CIE L*, a*, b* and ΔE*. Increase in concentration of nanoparticles in the dispersion imparted higher resistance to UV induced degradation. However, increased concentration of nanoparticles reduced the transparency of the coating. FTIR analysis indicated rapid degradation of lignin in uncoated and PG coated specimens due to UV exposure. Coating of wood surfaces with nanodispersions restricted lignin degradation. The study also demonstrates the potential of propylene glycol as a dispersant for developing stable and efficient UV protective nanodispersions for wood coating. Copyright © 2018 Elsevier B.V. All rights reserved.

Biodegradable mixed MPEG-SS-2SA/TPGS micelles for triggered intracellular release of paclitaxel and reversing multidrug resistance

PubMed Central

Dong, Kai; Yan, Yan; Wang, Pengchong; Shi, Xianpeng; Zhang, Lu; Wang, Ke; Xing, Jianfeng; Dong, Yalin

2016-01-01

In this study, a type of multifunctional mixed micelles were prepared by a novel biodegradable amphiphilic polymer (MPEG-SS-2SA) and a multidrug resistance (MDR) reversal agent (d-α-tocopheryl polyethylene glycol succinate, TPGS). The mixed micelles could achieve rapid intracellular drug release and reversal of MDR. First, the amphiphilic polymer, MPEG-SS-2SA, was synthesized through disulfide bonds between poly (ethylene glycol) monomethyl ether (MPEG) and stearic acid (SA). The structure of the obtained polymer was similar to poly (ethylene glycol)-phosphatidylethanolamine (PEG-PE). Then the mixed micelles, MPEG-SS-2SA/TPGS, were prepared by MPEG-SS-2SA and TPGS through the thin film hydration method and loaded paclitaxel (PTX) as the model drug. The in vitro release study revealed that the mixed micelles could rapidly release PTX within 24 h under a reductive environment because of the breaking of disulfide bonds. In cell experiments, the mixed micelles significantly inhibited the activity of mitochondrial respiratory complex II, also reduced the mitochondrial membrane potential, and the content of adenosine triphosphate, thus effectively inhibiting the efflux of PTX from cells. Moreover, in the confocal laser scanning microscopy, cellular uptake and 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assays, the MPEG-SS-2SA/TPGS micelles achieved faster release and more uptake of PTX in Michigan Cancer Foundation-7/PTX cells and showed better antitumor effects as compared with the insensitive control. In conclusion, the biodegradable mixed micelles, MPEG-SS-2SA/TPGS, could be potential vehicles for delivering hydrophobic chemotherapeutic drugs in MDR cancer therapy. PMID:27785018

Synthesis of covalently linked dimeric derivatives of chlorophyll a, pyrochlorophyll a, chlorophyll b, and bacteriochlorophyll a

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

Wasielewski, M.R.; Svec, W.A.

1980-05-09

Bis(chlorophyllide) ethylene glycol diesters were prepared for each of the title compounds. Pheophytins a and b isolated from alfalfa and bacteriochlorophyll a isolated from R. sphaeroides were treated with 80% aqueous trifluoroacetic acid to yield the corresponding pheophorbides. Pyropheophorbide was prepared by a literature procedure. Carbonic anhydride and benzotriazole-1-methanesulfonate activation methods were used in the esterification of the pheophorbides with ethylene glycol at ambient temperature. Each method yielded 75%+ of the pheophorbide ethylene glycol monoester. These monoesters were treated with equimolar amounts of the corresponding pheophorbide by using benzotriazol-1-methanesulfonate/4-(dimethylamino)pyridine in CH/sub 2/Cl/sub 2/ or dicyclohexylcarbodiimide/4-(dimethylamino)pyridine in CH/sub 2/Cl/sub 2/ atmore » ambient temperature. Yields of bis(phenophorbide) ethylene glycol diesters averaged about 50% for the former method and 70% for the latter method. Insertion of the magnesium atoms into the a series macrocycles was accomplished with iodomagnesium 2,6-di-tert-butyl-4-methylphenolate, IMgBHT, in CH/sub 2/Cl/sub 2/, while the metalation of the b and bacterial series macrocycles was carried out with a mixture of IMgBHT and lithium 2,2,6,6-tetramethylpiperidide in thiophen, all at ambient temperature. Both mono- and dimetalated derivatives were isolated and characterized in each case.« less

Photorespiration maintains carbon recycling efficiency at low irradiance despite impaired glycolate/glycerate antiport or hydroxypyruvate reduction

USDA-ARS?s Scientific Manuscript database

Photorespiration partially recycles fixed carbon that would otherwise be lost following the oxygenation reaction of Ribulose, 1-5, carboxylase oxygenase (Rubisco) and significantly reduces net photosynthesis in C3 plants. The recycling of photorespiratory C2 to C3 intermediates is not perfectly effi...

Chitosan cross-linked with poly(ethylene glycol)dialdehyde via reductive amination as effective controlled release carriers for oral protein drug delivery.

PubMed

Jing, Zi-Wei; Ma, Zhi-Wei; Li, Chen; Jia, Yi-Yang; Luo, Min; Ma, Xi-Xi; Zhou, Si-Yuan; Zhang, Bang-Le

2017-02-15

The covalently cross-linked chitosan-poly(ethylene glycol) 1540 derivatives have been developed as a controlled release system with potential for the delivery of protein drug. The swelling characteristics of the hydrogels based on these derivatives as the function of different PEG content and the release profiles of a model protein (bovine serum albumin, BSA) from the hydrogels were evaluated in simulated gastric fluid with or without enzyme in order to simulate the gastrointestinal tract conditions. The derivatives cross-linked with difunctional PEG 1540 -dialdehyde via reductive amination can swell in alkaline pH and remain insoluble in acidic medium. The cumulative release amount of BSA was relatively low in the initial 2h and increased significantly at pH 7.4 with intestinal lysozyme for additional 12h. The results proved that the release-and-hold behavior of the cross-linked CS-PEG 1540 H-CS hydrogel provided a swell and intestinal enzyme controlled release carrier system, which is suitable for oral protein drug delivery. Copyright © 2016 Elsevier Ltd. All rights reserved.

Single dose intratympanic mesna application inhibits propylene glycol induced cholesteatoma formation.

PubMed

Ismi, O; Karabulut, Y Y; Bal, K K; Vayisoglu, Y; Unal, M

2017-03-01

Mesna (i.e. sodium 2-mercaptoethanesulfonate; C2H5NaO3S2) has been used in otological surgery such as cholesteatoma dissection and tympanic membrane lateralisation in atelectatic ears. However, this study aimed to investigate its effect on cholesteatoma formation. A total of 20 Wistar rats were divided into two groups of 10 animals. The right and left ears of control animals were treated with saline (saline control group; n = 10 ears) and propylene glycol plus saline (propylene glycol control group; n = 10 ears), respectively. In the mesna group, both ears were treated with propylene glycol plus mesna (n = 20 ears). On days 1, 8 and 15, the saline control group had intratympanic injections of 0.2 ml saline and the propylene glycol control and mesna groups had intratympanic injections of 0.2 ml 100 per cent propylene glycol. On day 22, the propylene glycol control group had a single intratympanic injection of 0.2 ml saline and the mesna group had a single intratympanic injection of 10 per cent mesna. Animals were killed 12 weeks after the last injection and the temporal bones were sent for histopathological evaluation. The cholesteatoma formation rate was 88 per cent in the propylene glycol control group, but was significantly lower in the mesna group (p = 0.01). There were no significant differences in granulation tissue formation (p = 0.498), cyst formation in the bulla (p = 0.381), fibrosis (p = 0.072) and epithelial hyperplasia (p = 0.081) among experimental groups. Intratympanic propylene glycol administration is an effective method of promoting experimental cholesteatoma formation. Administration of a single dose of intratympanic mesna inhibited cholesteatoma formation in an animal model.

Impact of scaling on the nitric-glycolic acid flowsheet

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

Lambert, D.

Savannah River Remediation (SRR) is considering using glycolic acid as a replacement for formic acid in Sludge Receipt and Adjustment Tank (SRAT) processing in the Defense Waste Processing Facility (DWPF). Catalytic decomposition of formic acid is responsible for the generation of hydrogen, a potentially flammable gas, during processing. To prevent the formation of a flammable mixture in the offgas, an air purge is used to dilute the hydrogen concentration below the 60% of the Composite Lower Flammability Limit (CLFL). The offgas is continuously monitored for hydrogen using Gas Chromatographs (GCs). Since formic acid is much more volatile and toxic thanmore » glycolic acid, a formic acid spill would lead to the release of much larger quantities to the environment. Switching from formic acid to glycolic acid is expected to eliminate the hydrogen flammability hazard leading to lower air purges, thus downgrading of Safety Significant GCs to Process Support GCs, and minimizing the consequence of a glycolic acid tank leak in DWPF. Overall this leads to a reduction in process operation costs and an increase in safety margin. Experiments were completed at three different scales to demonstrate that the nitric-glycolic acid flowsheet scales from the 4-L lab scale to the 22-L bench scale and 220-L engineering scale. Ten process demonstrations of the sludge-only flowsheet for SRAT and Slurry Mix Evaporator (SME) cycles were performed using Sludge Batch 8 (SB8)-Tank 40 simulant. No Actinide Removal Process (ARP) product or strip effluent was added during the runs. Six experiments were completed at the 4-L scale, two experiments were completed at the 22-L scale, and two experiments were completed at the 220-L scale. Experiments completed at the 4-L scale (100 and 110% acid stoichiometry) were repeated at the 22-L and 220-L scale for scale comparisons.« less

Surface functionalization of thin-film diamond for highly stable and selective biological interfaces

PubMed Central

Stavis, Courtney; Clare, Tami Lasseter; Butler, James E.; Radadia, Adarsh D.; Carr, Rogan; Zeng, Hongjun; King, William P.; Carlisle, John A.; Aksimentiev, Aleksei; Bashir, Rashid; Hamers, Robert J.

2011-01-01

Carbon is an extremely versatile family of materials with a wide range of mechanical, optical, and mechanical properties, but many similarities in surface chemistry. As one of the most chemically stable materials known, carbon provides an outstanding platform for the development of highly tunable molecular and biomolecular interfaces. Photochemical grafting of alkenes has emerged as an attractive method for functionalizing surfaces of diamond, but many aspects of the surface chemistry and impact on biological recognition processes remain unexplored. Here we report investigations of the interaction of functionalized diamond surfaces with proteins and biological cells using X-ray photoelectron spectroscopy (XPS), atomic force microscopy, and fluorescence methods. XPS data show that functionalization of diamond with short ethylene glycol oligomers reduces the nonspecific binding of fibrinogen below the detection limit of XPS, estimated as > 97% reduction over H-terminated diamond. Measurements of different forms of diamond with different roughness are used to explore the influence of roughness on nonspecific binding onto H-terminated and ethylene glycol (EG)-terminated surfaces. Finally, we use XPS to characterize the chemical stability of Escherichia coli K12 antibodies on the surfaces of diamond and amine-functionalized glass. Our results show that antibody-modified diamond surfaces exhibit increased stability in XPS and that this is accompanied by retention of biological activity in cell-capture measurements. Our results demonstrate that surface chemistry on diamond and other carbon-based materials provides an excellent platform for biomolecular interfaces with high stability and high selectivity. PMID:20884854

Comparative Evaluation of Efficacy and Tolerability of Glycolic Acid, Salicylic Mandelic Acid, and Phytic Acid Combination Peels in Melasma.

PubMed

Sarkar, Rashmi; Garg, Vijay; Bansal, Shivani; Sethi, Sumit; Gupta, Chitra

2016-03-01

Melasma is acquired symmetric hypermelanosis characterized by light-to-deep brown pigmentation over cheeks, forehead, upper lip, and nose. Treatment of this condition is difficult and associated with high recurrence rates. Chemical peels have become a popular modality in the treatment of melasma. To compare the therapeutic efficacy and tolerability of glycolic acid (35%) versus salicylic-mandelic (SM) acid (20% salicylic/10% mandelic acid) versus phytic combination peels in Indian patients with melasma. Ninety patients diagnosed with melasma were randomly assigned into 3 groups of 30 patients each. Group A received glycolic acid (GA-35%) peel, Group B received SM acid, and Group C received phytic combination peels. Each group was primed with 4% hydroquinone and 0.05% tretinoin cream for 4 weeks before treatment. Chemical peeling was done after every 14 days in all groups until 12 weeks. Clinical evaluation using melasma area and severity index (MASI) score and photography was recorded at every visit and follow-up was done until 20 weeks. There was a decrease in MASI score in all 3 groups but it was statistically significantly lower in Group A than Group C (p = .00), and it was also statistically significantly lower in Group B than Group C (p = .00) but there was no statistically significant difference between Groups A and B (p = .876). Objective response to treatment evaluated by reduction in MASI scoring after 12 weeks was 62.36% reduction in GA group, 60.98% reduction in SM group, and 44.71% in phytic acid group. It is concluded that GA (35%) and SM acid peels are both equally efficacious and a safe treatment modality for melasma in Indian skin, and are more effective than phytic acid peels. Salicylic-mandelic peels are better tolerated and more suitable for Indian skin.

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.

Glycol ethers and semen quality: a cross‐sectional study among male workers in the Paris Municipality

PubMed Central

Multigner, L; Brik, E Ben; Arnaud, I; Haguenoer, J M; Jouannet, P; Auger, J; Eustache, F

2007-01-01

Objectives Apparent increases in human male reproductive disorders, including low sperm production, may have occurred because of increased chemical exposure. Various glycol ether‐based solvents have pronounced adverse effects on sperm production and male fertility in laboratory animals. The authors investigated the effects of past and current exposure to glycol ether‐containing products on semen quality and reproductive hormones among men employed by the Paris Municipality. Methods Between 2000 and 2001 the authors recruited 109 men who gave semen, blood and urine samples and underwent an andrological examination. Information on lifestyle, occupation, exposure and medical history was obtained by interview. According to their job and chemical products used during the period 1990–2000, men were classified as either occupationally exposed or non‐exposed. Current exposure levels to glycol ethers at the time of the study were evaluated by biological monitoring of six urinary metabolites. Results Previous exposure to glycol ethers was associated with an increased risk for sperm concentration, for rapid progressive motility and for morphologically normal sperm below the World Health Organization semen reference values. No effect of previous glycol ether exposure on hormones levels was observed. By contrast, current glycol ether exposure levels were low and not correlated with either seminal quality or hormone levels. Conclusions This study suggests that most glycol ethers currently used do not impact on human semen characteristics. Those that were more prevalent from the 1960s until recently may have long lasting negative effects on human semen quality. PMID:17332140

Glycolic Acid Peels/Azelaic Acid 20% Cream Combination and Low Potency Triple Combination Lead to Similar Reduction in Melasma Severity in Ethnic Skin: Results of a Randomized Controlled Study

PubMed Central

Mahajan, Rahul; Kanwar, Amrinder Jit; Parsad, Davinder; Kumaran, Muthu Sendhil; Sharma, Reena

2015-01-01

Background: Numerous therapeutic options have been tried in the management of melasma. Aims and Objectives: This prospective randomized study was planned to assess the efficacy of low potency triple combination (TC) cream (TC-hydroquinone 2%/tretinoin 0.05%/fluocinolone 0.01%) versus glycolic acid (GA) peels/azelaic acid (AA) 20% cream (GA/AA) combination in melasma. Materials and Methods: Forty patients with melasma were recruited into this study and randomized into two groups. Group A consisting 20 patients received TC cream once a day for night time application for 3 months. Group B comprising of 20 patients received GA/AA 20% cream combination for 3 months. The disease severity was monitored with digital photography, melasma area and severity index (MASI) score, which was calculated at baseline, 6 weeks and 12 weeks, and visual analog scale (VAS) score, which was calculated at baseline and 12 weeks. Results: Of 40 patients, 38 were completed the study. A significant reduction in MASI and VAS was recorded after 6 weeks and 12 weeks of treatment in both groups A and B (P = 0.001). However, there was no significant difference in the mean MASI scores between the two groups at baseline, 6 weeks and 12 weeks. Similarly, there was no difference in the mean VAS scores between the two groups at baseline and 12 weeks. Four patients in group A and 3 in group B experienced adverse effects such as irritation, dryness, and photosensitivity. Conclusion: Both low potency TC cream and GA/AA 20% cream combination are effective in treating melasma among Indian patients. PMID:25814702

Combination of glycolic acid peel and topical 20% azelaic acid cream in melasma patients: efficacy and improvement in quality of life.

PubMed

Dayal, Surabhi; Sahu, Priyadarshini; Dua, Ruchika

2017-03-01

Glycolic acid (GA) peel is one of the most versatile agents in the treatment of melasma. GA peeling alone or in combination with topical hypopigmenting agents has shown encouraging results. However, there is paucity of controlled trial demonstrating the efficacy of glycolic peel in conjunction with topical azelaic acid (AA). We therefore sought to highlight the efficacy and safety of this combination in melasma. To assess the clinical efficacy, safety and reduction in melasma quality of life (MELASQOL) scores on combining serial GA peels with topical 20% AA cream in epidermal melasma. Sixty patients of epidermal melasma were enrolled for 24 weeks. Patients were divided into two groups: (1) Study group received serial GA peel every 3 weeks with twice daily 20% AA cream, and (2) control group received only 20% AA cream. Clinical improvement was assessed objectively using Melasma Area Severity Index (MASI). Melasma-related quality of life was measured by MELASQOL scale in both groups. Side effects were observed at each visit. The improvement in MASI and percentage decrease in MASI scoring were statistically significant 12 weeks onwards in study group as compared to control group. There was also a significant reduction in MELASQOL scores in study group as compared to control group after treatment. Minor reversible side effects were observed in both groups, which did not require cessation of therapy. GA peel enhances therapeutic efficacy of topical AA cream for treatment of melasma, with improvement in quality of life without serious side effects. © 2016 Wiley Periodicals, Inc.

FY13 GLYCOLIC-NITRIC ACID FLOWSHEET DEMONSTRATIONS OF THE DWPF CHEMICAL PROCESS CELL WITH SIMULANTS

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

Lambert, D.; Zamecnik, J.; Best, D.

Savannah River Remediation is evaluating changes to its current Defense Waste Processing Facility flowsheet to replace formic acid with glycolic acid in order to improve processing cycle times and decrease by approximately 100x the production of hydrogen, a potentially flammable gas. Higher throughput is needed in the Chemical Processing Cell since the installation of the bubblers into the melter has increased melt rate. Due to the significant maintenance required for the safety significant gas chromatographs and the potential for production of flammable quantities of hydrogen, eliminating the use of formic acid is highly desirable. Previous testing at the Savannah Rivermore » National Laboratory has shown that replacing formic acid with glycolic acid allows the reduction and removal of mercury without significant catalytic hydrogen generation. Five back-to-back Sludge Receipt and Adjustment Tank (SRAT) cycles and four back-to-back Slurry Mix Evaporator (SME) cycles were successful in demonstrating the viability of the nitric/glycolic acid flowsheet. The testing was completed in FY13 to determine the impact of process heels (approximately 25% of the material is left behind after transfers). In addition, back-to-back experiments might identify longer-term processing problems. The testing was designed to be prototypic by including sludge simulant, Actinide Removal Product simulant, nitric acid, glycolic acid, and Strip Effluent simulant containing Next Generation Solvent in the SRAT processing and SRAT product simulant, decontamination frit slurry, and process frit slurry in the SME processing. A heel was produced in the first cycle and each subsequent cycle utilized the remaining heel from the previous cycle. Lower SRAT purges were utilized due to the low hydrogen generation. Design basis addition rates and boilup rates were used so the processing time was shorter than current processing rates.« less

EFFECT OF POLY (ETHYLENE GLYCOL) ON THE FORMATION OF NANOSTRUCTURES: A FACILE SUSTAINABLE APPROACH FOR THE SYNTHESIS OF SILVER NANORODS USING MICROWAVE IRRADIATION

EPA Science Inventory

Bulk synthesis of silver nanorods employing poly (ethylene glycol) (PEG) under microwave irradiation is reported. The formation of nanorods or particulate morphology is dependent on the PEG concentration. This greener method uses no surfactants or reducing agents and employs a b...

One-step extraction and quantitation of toxic alcohols and ethylene glycol in plasma by capillary gas chromatography (GC) with flame ionization detection (FID).

PubMed

Orton, Dennis J; Boyd, Jessica M; Affleck, Darlene; Duce, Donna; Walsh, Warren; Seiden-Long, Isolde

2016-01-01

Clinical analysis of volatile alcohols (i.e. methanol, ethanol, isopropanol, and metabolite acetone) and ethylene glycol (EG) generally employs separate gas chromatography (GC) methods for analysis. Here, a method for combined analysis of volatile alcohols and EG is described. Volatile alcohols and EG were extracted with 2:1 (v:v) acetonitrile containing internal standards (IS) 1,2 butanediol (for EG) and n-propanol (for alcohols). Samples were analyzed on an Agilent 6890 GC FID. The method was evaluated for precision, accuracy, reproducibility, linearity, selectivity and limit of quantitation (LOQ), followed by correlation to existing GC methods using patient samples, Bio-Rad QC, and in-house prepared QC material. Inter-day precision was from 6.5-11.3% CV, and linearity was verified from down to 0.6mmol/L up to 150mmol/L for each analyte. The method showed good recovery (~100%) and the LOQ was calculated to be between 0.25 and 0.44mmol/L. Patient correlation against current GC methods showed good agreement (slopes from 1.03-1.12, and y-intercepts from 0 to 0.85mmol/L; R(2)>0.98; N=35). Carryover was negligible for volatile alcohols in the measuring range, and of the potential interferences tested, only toluene and 1,3 propanediol interfered. The method was able to resolve 2,3 butanediol, diethylene glycol, and propylene glycol in addition to the peaks quantified. Here we describe a simple procedure for simultaneous analysis of EG and volatile alcohols that comes at low cost and with a simple liquid-liquid extraction requiring no derivitization to obtain adequate sensitivity for clinical specimens. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

N-alkylated aminopyrazines for use as hydrophilic optical agents

NASA Astrophysics Data System (ADS)

Poreddy, Amruta R.; Asmelash, Bethel; Galen, Karen P.; Fitch, Richard M.; Shieh, Jeng-Jong; Wilcox, James M.; Schoenstein, Tasha M.; Wojdyla, Jolette K.; Gaston, Kimberly R.; Freskos, John N.; Neumann, William L.; Rajagopalan, Raghavan; Ahn, Hyo-Yang; Kostelc, James G.; Debreczeny, Martin P.; Belfield, Kevin D.; Dorshow, Richard B.

2009-02-01

Rapid assessment of glomerular filtration rate (GFR), which measures the amount of plasma filtered through the kidney within a given time, would greatly facilitate monitoring of renal function for patients at the bedside in the clinic. In our pursuit to develop exogenous fluorescent tracers for real-time monitoring of renal function by optical methods, N-alkylated aminopyrazine dyes and their hydrophilic conjugates based on poly (ethylene glycol) (PEG) were synthesized via reductive amination as the key step. Photophysical properties indicated a bathochromic shift on the order of 50 nm in both absorption and emission compared to naked aminopyrazines which could be very useful in enhancing both tissue penetration as well as easier detection methods. Structure-activity relationship (SAR) and pharmacokinetic (PK) studies, and the correlation of in vivo optical data with plasma PK for measurement of clearance (and hence GFR) are focus of the current investigation.

Amperometric biosensor based on reductive H2O2 detection using pentacyanoferrate-bound polymer for creatinine determination.

PubMed

Nieh, Chi-Hua; Tsujimura, Seiya; Shirai, Osamu; Kano, Kenji

2013-03-12

Pentacyanoferrate-bound poly(1-vinylimidazole) (PVI[Fe(CN)5]) was selected as a mediator for amperometric creatinine determination based on the reductive H2O2 detection. Creatinine amidohydrolase (CNH), creatine amidohydrolase (CRH), sarcosine oxidase (SOD), peroxidase (POD), and PVI[Fe(CN)5] were crosslinked with poly(ethylene glycol) diglycidyl ether (PEGDGE) on a glassy carbon (GC) electrode for a creatinine biosensor fabrication. Reduction current was monitored at -0.1V in the presence of creatinine and O2. It is revealed that PVI[Fe(CN)5] is suitable as a mediator for a bioelectrocatalytic reaction of POD, since PVI[Fe(CN)5] neither reacts with reactants nor works as an electron acceptor of SOD. The amounts of PVI[Fe(CN)5], PEGDGE, and enzymes were optimized toward creatinine detection. Nafion as a protecting film successfully prevented the enzyme layer from interferences. The detection limit and linear range in creatinine determination were 12μM and 12-500μM (R(2)=0.993), respectively, and the sensitivity was 11mAcm(-2)M(-1), which is applicable for urine creatinine tests. The results of the creatinine determination for four urine samples measured with this proposed method were compared with Jaffe method, and a good correlation was obtained between the results. Copyright © 2013 Elsevier B.V. All rights reserved.

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.

40 CFR Table 6 to Subpart Jj of... - VHAP of Potential Concern

Code of Federal Regulations, 2011 CFR

2011-07-01

... glycol butyl ether, ethylene glycol ethyl ether (2-ethoxy ethanol), ethylene glycol hexyl ether, ethylene..., ethylene glycol mono-2-ethylhexyl ether, diethylene glycol butyl ether, diethylene glycol ethyl ether... glycol propyl ether, triethylene glycol butyl ether, triethylene glycol ethyl ether, triethylene glycol...

Specific Inhibition of Hepatic Lactate Dehydrogenase Reduces Oxalate Production in Mouse Models of Primary Hyperoxaluria.

PubMed

Lai, Chengjung; Pursell, Natalie; Gierut, Jessica; Saxena, Utsav; Zhou, Wei; Dills, Michael; Diwanji, Rohan; Dutta, Chaitali; Koser, Martin; Nazef, Naim; Storr, Rachel; Kim, Boyoung; Martin-Higueras, Cristina; Salido, Eduardo; Wang, Weimin; Abrams, Marc; Dudek, Henryk; Brown, Bob D

2018-06-15

Primary hyperoxalurias (PHs) are autosomal recessive disorders caused by the overproduction of oxalate leading to calcium oxalate precipitation in the kidney and eventually to end-stage renal disease. One promising strategy to treat PHs is to reduce the hepatic production of oxalate through substrate reduction therapy by inhibiting liver-specific glycolate oxidase (GO), which controls the conversion of glycolate to glyoxylate, the proposed main precursor to oxalate. Alternatively, diminishing the amount of hepatic lactate dehydrogenase (LDH) expression, the proposed key enzyme responsible for converting glyoxylate to oxalate, should directly prevent the accumulation of oxalate in PH patients. Using RNAi, we provide the first in vivo evidence in mammals to support LDH as the key enzyme responsible for converting glyoxylate to oxalate. In addition, we demonstrate that reduction of hepatic LDH achieves efficient oxalate reduction and prevents calcium oxalate crystal deposition in genetically engineered mouse models of PH types 1 (PH1) and 2 (PH2), as well as in chemically induced PH mouse models. Repression of hepatic LDH in mice did not cause any acute elevation of circulating liver enzymes, lactate acidosis, or exertional myopathy, suggesting further evaluation of liver-specific inhibition of LDH as a potential approach for treating PH1 and PH2 is warranted. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Poly (lactic-co-glycolic acid) particles prepared by microfluidics and conventional methods. Modulated particle size and rheology.

PubMed

Perez, Aurora; Hernández, Rebeca; Velasco, Diego; Voicu, Dan; Mijangos, Carmen

2015-03-01

Microfluidic techniques are expected to provide narrower particle size distribution than conventional methods for the preparation of poly (lactic-co-glycolic acid) (PLGA) microparticles. Besides, it is hypothesized that the particle size distribution of poly (lactic-co-glycolic acid) microparticles influences the settling behavior and rheological properties of its aqueous dispersions. For the preparation of PLGA particles, two different methods, microfluidic and conventional oil-in-water emulsification methods were employed. The particle size and particle size distribution of PLGA particles prepared by microfluidics were studied as a function of the flow rate of the organic phase while particles prepared by conventional methods were studied as a function of stirring rate. In order to study the stability and structural organization of colloidal dispersions, settling experiments and oscillatory rheological measurements were carried out on aqueous dispersions of PLGA particles with different particle size distributions. Microfluidics technique allowed the control of size and size distribution of the droplets formed in the process of emulsification. This resulted in a narrower particle size distribution for samples prepared by MF with respect to samples prepared by conventional methods. Polydisperse samples showed a larger tendency to aggregate, thus confirming the advantages of microfluidics over conventional methods, especially if biomedical applications are envisaged. Copyright © 2014 Elsevier Inc. All rights reserved.

Enhancement of convective heat transfer coefficient of ethylene glycol base cuprous oxide (Cu2O) nanofluids

NASA Astrophysics Data System (ADS)

Hassan, Ali; Ramzan, Naveed; Umer, Asim; Ahmad, Ayyaz; Muryam, Hina

2018-02-01

The enhancement in the convective heat transfer coefficient of the ethylene glycol (EG) base cuprous oxide (Cu2O) nanofluids were investigated. The nanofluids of different volume concentrations i-e 1%, 2.5% and 4.5% were prepared by the two step method. Cuprous oxide (Cu2O) nanoparticles were ultrasonically stirred for four hours in the ethylene glycol (EG). The experimental study has been performed through circular tube geometry in laminar flow regime at average Reynolds numbers 36, 71 and 116. The constant heat flux Q = 4000 (W/m2) was maintained during this work. Substantial enhancement was observed in the convective heat transfer coefficient of ethylene glycol (EG) base cuprous oxide (Cu2O) nanofluids than the base fluid. The maximum 74% enhancement was observed in convective heat transfer coefficient at 4.5 vol% concentration and Re = 116.

An optimization study of PtSn/C catalysts applied to direct ethanol fuel cell: Effect of the preparation method on the electrocatalytic activity of the catalysts

NASA Astrophysics Data System (ADS)

Almeida, T. S.; Palma, L. M.; Leonello, P. H.; Morais, C.; Kokoh, K. B.; De Andrade, A. R.

2012-10-01

The aim of this work was to perform a systematic study of the parameters that can influence the composition, morphology, and catalytic activity of PtSn/C nanoparticles and compare two different methods of nanocatalyst preparation, namely microwave-assisted heating (MW) and thermal decomposition of polymeric precursors (DPP). An investigation of the effects of the reducing and stabilizing agents on the catalytic activity and morphology of Pt75Sn25/C catalysts prepared by microwave-assisted heating was undertaken for optimization purposes. The effect of short-chain alcohols such as ethanol, ethylene glycol, and propylene glycol as reducing agents was evaluated, and the use of sodium acetate and citric acid as stabilizing agents for the MW procedure was examined. Catalysts obtained from propylene glycol displayed higher catalytic activity compared with catalysts prepared in ethylene glycol. Introduction of sodium acetate enhanced the catalytic activity, but this beneficial effect was observed until a critical acetate concentration was reached. Optimization of the MW synthesis allowed for the preparation of highly dispersed catalysts with average sizes lying between 2.0 and 5.0 nm. Comparison of the best catalyst prepared by MW with a catalyst of similar composition prepared by the polymeric precursors method showed that the catalytic activity of the material can be improved when a proper condition for catalyst preparation is achieved.

Determination of semi-volatile additives in wines using SPME and GC-MS.

PubMed

Sagandykova, Gulyaim N; Alimzhanova, Mereke B; Nurzhanova, Yenglik T; Kenessov, Bulat

2017-04-01

Parameters of headspace solid-phase microextraction, such as fiber coating (85μm CAR/PDMS), extraction time (2min for white and 3min for red wines), temperature (85°C), pre-incubation time (15min) were optimized for identification and quantification of semi-volatile additives (propylene glycol, sorbic and benzoic acids) in wines. To overcome problems in their determination, an evaporation of the wine matrix was performed. Using the optimized method, screening of 25 wine samples was performed, and the presence of propylene glycol, sorbic and benzoic acids was found in 22, 20 and 6 samples, respectively. Analysis of different wines using a standard addition approach showed good linearity in concentration ranges 0-250, 0-125, and 0-250mg/L for propylene glycol, sorbic and benzoic acids, respectively. The proposed method can be recommended for quality control of wine and disclosing adulterated samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

Actual Waste Demonstration of the Nitric-Glycolic Flowsheet for Sludge Batch 9 Qualification

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

J. D. Newell; Pareizs, J. M.; Martino, C. J.

For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) performs qualification testing to demonstrate that the sludge batch is processable. Testing performed by the Savannah River National Laboratory has shown glycolic acid to be effective in replacing the function of formic acid in the DWPF chemical process. The nitric-glycolic flowsheet reduces mercury, significantly lowers the catalytic generation of hydrogen and ammonia which could allow purge reduction in the Sludge Receipt and Adjustment Tank (SRAT), stabilizes the pH and chemistry in the SRAT and the Slurry Mix Evaporator (SME), allowsmore » for effective rheology adjustment, and is favorable with respect to melter flammability. In order to implement the new flowsheet, SRAT and SME cycles, designated SC-18, were performed using a Sludge Batch (SB) 9 slurry blended from SB8 Tank 40H and Tank 51H samples. The SRAT cycle involved adding nitric and glycolic acids to the sludge, refluxing to steam strip mercury, and dewatering to a targeted solids concentration. Data collected during the SRAT cycle included offgas analyses, process temperatures, heat transfer, and pH measurements. The SME cycle demonstrated the addition of glass frit and the replication of six canister decontamination additions. The demonstration concluded with dewatering to a targeted solids concentration. Data collected during the SME cycle included offgas analyses, process temperatures, heat transfer, and pH measurements. Slurry and condensate samples were collected for subsequent analysis« less

Sludge batch 9 simulant runs using the nitric-glycolic acid flowsheet

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

Lambert, D. P.; Williams, M. S.; Brandenburg, C. H.

Testing was completed to develop a Sludge Batch 9 (SB9) nitric-glycolic acid chemical process flowsheet for the Defense Waste Processing Facility’s (DWPF) Chemical Process Cell (CPC). CPC simulations were completed using SB9 sludge simulant, Strip Effluent Feed Tank (SEFT) simulant and Precipitate Reactor Feed Tank (PRFT) simulant. Ten sludge-only Sludge Receipt and Adjustment Tank (SRAT) cycles and four SRAT/Slurry Mix Evaporator (SME) cycles, and one actual SB9 sludge (SRAT/SME cycle) were completed. As has been demonstrated in over 100 simulations, the replacement of formic acid with glycolic acid virtually eliminates the CPC’s largest flammability hazards, hydrogen and ammonia. Recommended processingmore » conditions are summarized in section 3.5.1. Testing demonstrated that the interim chemistry and Reduction/Oxidation (REDOX) equations are sufficient to predict the composition of DWPF SRAT product and SME product. Additional reports will finalize the chemistry and REDOX equations. Additional testing developed an antifoam strategy to minimize the hexamethyldisiloxane (HMDSO) peak at boiling, while controlling foam based on testing with simulant and actual waste. Implementation of the nitric-glycolic acid flowsheet in DWPF is recommended. This flowsheet not only eliminates the hydrogen and ammonia hazards but will lead to shorter processing times, higher elemental mercury recovery, and more concentrated SRAT and SME products. The steady pH profile is expected to provide flexibility in processing the high volume of strip effluent expected once the Salt Waste Processing Facility starts up.« less

Glycofunctionalization of Poly(lactic- co-glycolic acid) Polymers: Building Blocks for the Generation of Defined Sugar-Coated Nanoparticles.

PubMed

Palmioli, Alessandro; La Ferla, Barbara

2018-06-15

A set of poly(lactic- co-glycolic acid) polymers functionalized with different monosaccharides as well as glycodendrimers and surface-decorated nanoparticles (NPs) were synthesized and characterized. The functionalization of the polymer was carried out through amide bond formation with amino-modified sugar monomers and through a biocompatible chemoselective method exploiting the reducing end of a free sugar. The assemblage of the NPs adopting a nanoprecipitation method was straightforward and allowed the preparation of sugars/sugar dendrimer coated NPs.

Determination of ethylene oxide, ethylene chlorohydrin, and ethylene glycol in aqueous solutions and ethylene oxide residues in associated plastics.

PubMed

Ball, N A

1984-09-01

A gas chromatographic (GC) method was developed for the determination of ethylene oxide and its two reaction products, ethylene chlorohydrin and ethylene glycol, in aqueous ophthalmic solutions. Propylene oxide was used as an internal standard. All three components were determined in one isothermal chromatographic analysis in less than 15 min. An extraction method for the determination of ethylene oxide residues in plastic components was also developed, and certain plastics with different ethylene oxide retention characteristics were identified.

Treatment of Grade II and III Actinic Keratosis Lesions with a Film-Forming Medical Device Containing Sunscreen/Piroxicam 0.8% and a Retinoic Acid/Glycolic Gel: A Pilot Trial.

PubMed

Puviani, Mario; Milani, Massimo

2018-05-31

Lesion and field-targeted treatments of actinic keratosis (AK) are commonly indicated for grade I and II type lesions. Grade III lesions are in general more difficult to treat. A film-forming medical device containing piroxicam 0.8% and sunscreen (SPF 50+) (PS) has been shown to be effective in the treatment of grade I and II AK lesions. Topical and oral retinoids have been utilized in AK and non-melanoma skin cancers. Topical glycolic acid promotes keratolysis and stimulates collagen synthesis for repair and skin rejuvenation and could be useful in AK treatment strategies. A gel containing retinoid acid (0.02%) and glycolic acid (4%) (RC) is commercially available. The objective of the study was to evaluate the efficacy and local tolerability of a combined treatment approach with PS and RC in subjects with multiple grade II and III AK lesions. Twenty-two subjects (16 males and 6 females; mean age 68 years) with more than five AK lesions were enrolled after obtaining their informed consent in a 3-month trial. PS cream was applied twice daily every day and RC gel was applied twice daily for 2 consecutive days every week. The primary endpoint was the evolution of the AK mean number from baseline to the end of the trial. Secondary endpoints were the thickness of the target lesion (expressed in mm 3 ) and the erythema score (hemoglobin content), evaluated using a standardized computer-based image acquisition analysis system (Anthera 3D). At baseline, the mean (SD) lesion number was 7.7 (3) for grade II and 1.4 (1) for grade III AK. At the end of the study, a significant (P = 0.001) reduction was observed for both grade II (- 81%; from 7.7 to 1.5) and grade III (- 22%) lesions. Six grade III lesions out of 31 (20%), presented at baseline, completely disappeared at month 3. For grade III lesions, a significant mean thickness reduction of 51% was observed at month 3. The erythema score (all lesions) was reduced by 70%. Four patients out of 22 (18%) were completely free of AK lesions at month 3. No severe side effects were reported. In this exploratory trial, a combined treatment with a cream containing piroxicam and sunscreen and a retinoic/glycolic gel was associated with a substantial reduction of both grade II and III AK lesions with good local tolerability. Cantabria Labs Difa Cooper.

Carbon-neutral energy cycles using alcohols.

PubMed

Fukushima, Takashi; Kitano, Sho; Hata, Shinichi; Yamauchi, Miho

2018-01-01

We demonstrated carbon-neutral (CN) energy circulation using glycolic acid ( GC )/oxalic acid ( OX ) redox couple. Here, we report fundamental studies on both catalyst search for power generation process, i.e. GC oxidation, and elemental steps for fuel generation process, i.e. OX reduction, in CN cycle. The catalytic activity test on various transition metals revealed that Rh, Pd, Ir, and Pt have preferable features as a catalyst for electrochemical oxidation of GC . A carbon-supported Pt catalyst in alkaline conditions exhibited higher activity, durability, and product selectivity for electrooxidation of GC rather than those in acidic media. The kinetic study on OX reduction clearly indicated that OX reduction undergoes successive two-electron reductions to form GC . Furthermore, application of TiO 2 catalysts with large specific area for electrochemical reduction of OX facilitates the selective formation of GC .

Carbon-neutral energy cycles using alcohols

PubMed Central

Fukushima, Takashi; Kitano, Sho; Hata, Shinichi; Yamauchi, Miho

2018-01-01

Abstract We demonstrated carbon-neutral (CN) energy circulation using glycolic acid (GC)/oxalic acid (OX) redox couple. Here, we report fundamental studies on both catalyst search for power generation process, i.e. GC oxidation, and elemental steps for fuel generation process, i.e. OX reduction, in CN cycle. The catalytic activity test on various transition metals revealed that Rh, Pd, Ir, and Pt have preferable features as a catalyst for electrochemical oxidation of GC. A carbon-supported Pt catalyst in alkaline conditions exhibited higher activity, durability, and product selectivity for electrooxidation of GC rather than those in acidic media. The kinetic study on OX reduction clearly indicated that OX reduction undergoes successive two-electron reductions to form GC. Furthermore, application of TiO2 catalysts with large specific area for electrochemical reduction of OX facilitates the selective formation of GC. PMID:29511392

Electro-oxidation of methanol and ethanol using PtRu/C, PtSn/C and PtSnRu/C electrocatalysts prepared by an alcohol-reduction process

NASA Astrophysics Data System (ADS)

Neto, Almir Oliveira; Dias, Ricardo R.; Tusi, Marcelo M.; Linardi, Marcelo; Spinacé, Estevam V.

PtRu/C, PtSn/C and PtSnRu/C electrocatalysts were prepared by the alcohol reduction process using ethylene glycol as the solvent and reduction agent and Vulcan Carbon XC72 as the support. The electrocatalysts were characterized by EDX, XRD and cyclic voltammetry. The electrochemical oxidation of methanol and ethanol were studied by chronoamperometry using a thin porous coating technique. The PtSn/C electrocatalyst prepared by this methodology showed superior performance compared to the PtRu/C and PtSnRu/C electrocatalysts for methanol and ethanol oxidation at room temperature.

Diazeniumdiolate-doped poly(lactic-co-glycolic acid)-based nitric oxide releasing films as antibiofilm coatings.

PubMed

Cai, Wenyi; Wu, Jianfeng; Xi, Chuanwu; Meyerhoff, Mark E

2012-11-01

Nitric oxide (NO) releasing films with a bilayer configuration are fabricated by doping dibutyhexyldiamine diazeniumdiolate (DBHD/N2O2) in a poly(lactic-co-glycolic acid) (PLGA) layer and further encapsulating this base layer with a silicone rubber top coating. By incorporating pH sensitive dyes within the films, pH changes in the PLGA layer are visualized and correlated with the NO release profiles (flux vs. time). It is demonstrated that PLGA acts as both a promoter and controller of NO release from the coating by providing protons through its intrinsic acid residues (both end groups and monomeric acid impurities) and hydrolysis products (lactic acid and glycolic acid). Control of the pH changes within the PLGA layer can be achieved by adjusting the ratio of DBHD/N2O2 and utilizing PLGAs with different hydrolysis rates. Coatings with a variety of NO release profiles are prepared with lifetimes of up to 15 d at room temperature (23 °C) and 10 d at 37 °C. When incubated in a CDC flow bioreactor for a one week period at RT or 37 °C, all the NO releasing films exhibit considerable antibiofilm properties against gram-positive Staphylococcus aureus and gram-negative Escherichia coli. In particular, compared to the silicone rubber surface alone, an NO releasing film with a base layer of 30 wt% DBHD/N2O2 mixed with poly(lactic acid) exhibits an ∼98.4% reduction in biofilm biomass of S. aureus and ∼99.9% reduction for E. coli at 37 °C. The new diazeniumdiolate-doped PLGA-based NO releasing coatings are expected to be useful antibiofilm coatings for a variety of indwelling biomedical devices (e.g., catheters). Copyright © 2012 Elsevier Ltd. All rights reserved.

Optimization of the Mechanical Properties and Residual Stresses in 2024 Aluminum Alloy Through Heat Treatment

NASA Astrophysics Data System (ADS)

Araghchi, M.; Mansouri, H.; Vafaei, R.; Guo, Y.

2018-05-01

Residual stresses induced during quenching of aluminum alloys cause dimensional instability and distortion. In this study, the effects of different concentrations of polyalkylene glycol (PAG) quenchants on residual stresses and mechanical properties of 2024 aluminum alloy were investigated. Surface residual stresses were measured by using hole-drilling strain-gauge method. Also, mechanical properties and microstructure of the heat-treated samples were analyzed using hardness measurements, tensile tests, and transmission electron microscopy. Results showed that quenching into a 15% polymeric solution and aging at 190 °C for 12 h cause 50% reduction in residual stress as compared with quenching in water at 20 °C and naturally aging. Moreover, tensile strength decreased by 104 MPa ( 20%) in compared with the T6 sample.

Alcea rosea root extract as a preventive and curative agent in ethylene glycol-induced urolithiasis in rats

PubMed Central

Ahmadi, Marzieh; Rad, Abolfazl Khajavi; Rajaei, Ziba; Hadjzadeh, Mousa-Al-Reza; Mohammadian, Nema; Tabasi, Nafiseh Sadat

2012-01-01

Introduction: Alcea rosea L. is used in Asian folk medicine as a remedy for a wide range of ailments. The aim of the present study was to investigate the effect of hydroalcoholic extract of Alcea rosea roots on ethylene glycol-induced kidney calculi in rats. Materials and Methods: Male Wistar rats were randomly divided into control, ethylene glycol (EG), curative and preventive groups. Control group received tap drinking water for 28 days. Ethylene glycol (EG), curative and preventive groups received 1% ethylene glycol for induction of calcium oxalate (CaOx) calculus formation; preventive and curative subjects also received the hydroalcoholic extract of Alcea rosea roots in drinking water at dose of 170 mg/kg, since day 0 or day 14, respectively. Urinary oxalate concentration was measured by spectrophotometer on days 0, 14 and 28. On day 28, the kidneys were removed and examined histopathologically under light microscopy for counting the calcium oxalate deposits in 50 microscopic fields. Results: In both preventive and curative protocols, treatment of rats with hydroalcoholic extract of Alcea rosea roots significantly reduced the number of kidney calcium oxalate deposits compared to ethylene glycol group. Administration of Alcea rosea extract also reduced the elevated urinary oxalate due to ethylene glycol. Conclusion: Alcea rosea showed a beneficial effect in preventing and eliminating calcium oxalate deposition in the rat kidney. This effect is possibly due to diuretic and anti-inflammatory effects or presence of mucilaginous polysaccharides in the plant. It may also be related to lowering of urinary concentration of stone-forming constituents. PMID:22701236

Optimization of reactive simulated moving bed systems with modulation of feed concentration for production of glycol ether ester.

PubMed

Agrawal, Gaurav; Oh, Jungmin; Sreedhar, Balamurali; Tie, Shan; Donaldson, Megan E; Frank, Timothy C; Schultz, Alfred K; Bommarius, Andreas S; Kawajiri, Yoshiaki

2014-09-19

In this article, we extend the simulated moving bed reactor (SMBR) mode of operation to the production of propylene glycol methyl ether acetate (DOWANOL™ PMA glycol ether) through the esterification of 1-methoxy-2-propanol (DOWANOL™ PM glycol ether) and acetic acid using AMBERLYST™ 15 as a catalyst and adsorbent. In addition, for the first time, we integrate the concept of modulation of the feed concentration (ModiCon) to SMBR operation. The performance of the conventional (constant feed) and ModiCon operation modes of SMBR are analyzed and compared. The SMBR processes are designed using a model based on a multi-objective optimization approach, where a transport dispersive model with a linear driving force for the adsorption rate has been used for modeling the SMBR system. The adsorption equilibrium and kinetics parameters are estimated from the batch and single column injection experiments by the inverse method. The multiple objectives are to maximize the production rate of DOWANOL™ PMA glycol ether, maximize the conversion of the esterification reaction and minimize the consumption of DOWANOL™ PM glycol ether which also acts as the desorbent in the chromatographic separation. It is shown that ModiCon achieves a higher productivity by 12-36% over the conventional operation with higher product purity and recovery. Copyright © 2014 Elsevier B.V. All rights reserved.

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

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

Wiedenman, B. J.; White, T. L.; Mahannah, R. N.

Ion Chromatography (IC) is the principal analytical method used to support studies of Sludge Reciept and Adjustment Tank (SRAT) chemistry at DWPF. A series of prior analytical ''Round Robin'' (RR) studies included both supernate and sludge samples from SRAT simulant, previously reported as memos, are tabulated in this report.2,3 From these studies it was determined to standardize IC column size to 4 mm diameter, eliminating the capillary column from use. As a follow on test, the DWPF laboratory, the PSAL laboratory, and the AD laboratory participated in the current analytical RR to determine a suite of anions in SRAT simulantmore » by IC, results also are tabulated in this report. The particular goal was to confirm the laboratories ability to measure and quantitate glycolate ion. The target was + or - 20% inter-lab agreement of the analyte averages for the RR. Each of the three laboratories analyzed a batch of 12 samples. For each laboratory, the percent relative standard deviation (%RSD) of the averages on nitrate, glycolate, and oxalate, was 10% or less. The three laboratories all met the goal of 20% relative agreement for nitrate and glycolate. For oxalate, the PSAL laboratory reported an average value that was 20% higher than the average values reported by the DWPF laboratory and the AD laboratory. Because of this wider window of agreement, it was concluded to continue the practice of an additional acid digestion for total oxalate measurement. It should also be noted that large amounts of glycolate in the SRAT samples will have an impact on detection limits of near eluting peaks, namely Fluoride and Formate. A suite of scoping experiments are presented in the report to identify and isolate other potential interlaboratory disceprancies. Specific ion chromatography inter-laboratory method conditions and differences are tabulated. Most differences were minor but there are some temperature control equipment differences that are significant leading to a recommendation of a heated jacket for analytical columns that are remoted for use in radiohoods. A suggested method improvement would be to implement column temperture control at a temperature slightly above ambient to avoid peak shifting due to temperature fluctuations. Temperature control in this manner would improve short and longer term peak retention time stability. An unknown peak was observed during the analysis of glycolic acid and SRAT simulant. The unknown peak was determined to best match diglycolic acid. The development of a method for acetate is summaraized, and no significant amount of acetate was observed in the SRAT products tested. In addition, an alternative Gas Chromatograph (GC) method for glycolate is summarized.« less

Oxidation of Ethylene Glycol by a Salt-Requiring Bacterium

PubMed Central

Caskey, William H.; Taber, Willard A.

1981-01-01

Bacterium T-52, cultured on ethylene glycol, readily oxidized glycolate and glyoxylate and exhibited elevated activities of ethylene glycol dehydrogenase and glycolate oxidase. Labeled glyoxylate was identified in reaction mixtures containing [14C]-ethylene glycol, but no glycolate was detected. The most likely pathway of ethylene glycol catabolism by bacterium T-52 is sequential oxidation to glycolate and glyoxylate. PMID:16345810

Docetaxel-loaded polylactic acid-co-glycolic acid nanoparticles: formulation, physicochemical characterization and cytotoxicity studies.

PubMed

Pradhan, Roshan; Poudel, Bijay Kumar; Ramasamy, Thiruganesh; Choi, Han-Gon; Yong, Chul Soon; Kim, Jong Oh

2013-08-01

In the present study, we developed novel docetaxel (DTX)-loaded polylactic acid-co-glycolic acid (PLGA) nanoparticles (NPs) using the combination of sodium lauryl sulfate (SLS) and poloxamer 407, the anionic and non-ionic surfactants respectively for stabilization. The NPs were prepared by emulsification/solvent evaporation method. The combination of these surfactants at weight ratio of 1:0.5 was able to produce uniformly distributed small sized NPs and demonstrated the better stability of NP dispersion with high encapsulation efficiency (85.9 +/- 0.6%). The drug/polymer ratio and phase ratio were 2:10 and 1:10, respectively. The optimized formulation of DTX-loaded PLGA NPs had a particle size and polydispersity index of 104.2 +/- 1.5 nm and 0.152 +/- 0.006, respectively, which was further supported by TEM image. In vitro release study was carried out with dialysis membrane and showed 32% drug release in 192 h. When in vitro release data were fitted to Korsmeyer-Peppas model, the n value was 0.481, which suggested the drug was released by anomalous or non-Fickian diffusion. In addition, DTX-loaded PLGA NPs in 72 h, displayed approximately 75% cell viability reduction at 10 microg/ml DTX concentration, in MCF-7 cell lines, indicating sustained release from NPs. Therefore, our results demonstrated that incorporation of DTX into PLGA NPs could provide a novel effective nanocarrier for the treatment of cancer.

Enhanced antioxidant effect of trans-resveratrol: potential of binary systems with polyethylene glycol and cyclodextrin.

PubMed

Moyano-Mendez, Josè Ramon; Fabbrocini, Gabriella; De Stefano, Daniela; Mazzella, Caterina; Mayol, Laura; Scognamiglio, Immacolata; Carnuccio, Rosa; Ayala, Fabio; La Rotonda, Maria Immacolata; De Rosa, Giuseppe

2014-10-01

Trans-resveratrol, a polyphenol extracted from Vitis vinifera, has different beneficial effects following its administration on the skin. Here the potential use of binary systems to enhance in vitro and in vivo activity of trans-resveratrol was investigated. Thus the aqueous solubility of trans-resveratrol was investigated in the presence of growing concentrations of polyethylene glycol (PEG) or β-cyclodextrin (βCD) as solubilizing excipients. Then, the solid dispersion of trans-resveratrol with PEG or inclusion complexes trans-resveratrol/βCD were prepared and characterised by different methods. Cytotoxicity and inhibition of reactive oxygen species (ROS) following H2O2 challenge in the presence of trans-resveratrol, alone or associated to the excipients, was evaluated on human keratinocyte HaCaT cell line. Both the trans-resveratrol-containing binary systems induced significant reduction of H2O2-induced ROS production, especially in the case of βCD that was selected for the following phase of the study. Thus, the effect of a cream containing trans-resveratrol, alone or associated to βCD, on different skin parameters such as corneometry, colorimetry and elastometry, was evaluated on human volunteers. All patients showed a visible improvement of clinical conditions with a remarkable decrease of aging signs, but this effect was higher of the hemi face treated with the βCD-containing formulation versus formulation containing trans-resveratrol alone.

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.

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.

In vivo comparison of the optical clearing efficacy of optical clearing agents in human skin by quantifying permeability using optical coherence tomography.

PubMed

Guo, Xiao; Guo, Zhouyi; Wei, Huajiang; Yang, Hongqin; He, Yonghong; Xie, Shusen; Wu, Guoyong; Deng, Xiaoyuan; Zhao, Qingliang; Li, Lanquan

2011-01-01

The objective of this work is to quantify and compare the optical clearing efficacy of glucose, propylene glycol, glycerol solutions through the human skin tissue in vivo by calculating permeability coefficient of three solutions. Currently, the permeability coefficient of agent in tissues was extracted from optical coherence tomography (OCT) amplitude data mainly through the OCT signal slope and the OCT amplitude methods. In this study, we report the OCT attenuation coefficient method which is a relatively novel and rarely reported methodology to measure the permeability coefficient during the optical skin clearing procedure. The permeability coefficients for 40% propylene glycol, glucose and glycerol were (2.74 ± 0.05) × 10(-6) cm s(-1), (1.78 ± 0.04) × 10(-6) cm s(-1) and (1.67 ± 0.04) × 10(-6) cm s(-1), respectively. It could be clearly seen that the permeability coefficient of the 40% propylene glycol solution is higher than that of 40% glucose solution, and the permeability coefficient of the 40% glucose solution is higher than that of the 40% glycerol solution. These indicate 40% propylene glycol solution is more effective than others in the human skin in vivo. We then compare and prove consistency of optical clearing efficacy figured out by three different methods. © 2011 The Authors. Photochemistry and Photobiology © 2011 The American Society of Photobiology.

Optimization and validation of liquid chromatography and headspace-gas chromatography based methods for the quantitative determination of capsaicinoids, salicylic acid, glycol monosalicylate, methyl salicylate, ethyl salicylate, camphor and l-menthol in a topical formulation.

PubMed

Pauwels, Jochen; D'Autry, Ward; Van den Bossche, Larissa; Dewever, Cédric; Forier, Michel; Vandenwaeyenberg, Stephanie; Wolfs, Kris; Hoogmartens, Jos; Van Schepdael, Ann; Adams, Erwin

2012-02-23

Capsaicinoids, salicylic acid, methyl and ethyl salicylate, glycol monosalicylate, camphor and l-menthol are widely used in topical formulations to relieve local pain. For each separate compound or simple mixtures, quantitative analysis methods are reported. However, for a mixture containing all above mentioned active compounds, no assay methods were found. Due to the differing physicochemical characteristics, two methods were developed and optimized simultaneously. The non-volatile capsaicinoids, salicylic acid and glycol monosalicylate were analyzed with liquid chromatography following liquid-liquid extraction, whereas the volatile compounds were analyzed with static headspace-gas chromatography. For the latter method, liquid paraffin was selected as compatible dilution solvent. The optimized methods were validated in terms of specificity, linearity, accuracy and precision in a range of 80% to 120% of the expected concentrations. For both methods, peaks were well separated without interference of other compounds. Linear relationships were demonstrated with R² values higher than 0.996 for all compounds. Accuracy was assessed by performing replicate recovery experiments with spiked blank samples. Mean recovery values were all between 98% and 102%. Precision was checked at three levels: system repeatability, method precision and intermediate precision. Both methods were found to be acceptably precise at all three levels. Finally, the method was successfully applied to the analysis of some real samples (cutaneous sticks). Copyright © 2011 Elsevier B.V. All rights reserved.

SU-E-T-284: Dose Plan Optimization When Using Hydrogel Prostate-Rectum Spacer: A Single Institution Experience

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

Rajecki, M; Thurber, A; Catalfamo, F

2015-06-15

Purpose: To describe rectal dose reduction achieved and techniques used to take advantage of the increased peri-rectal spacing provided by injected polyethylene-glycol. Methods: Thirty prostate cancer patents were 2:1 randomized during a clinical trial to evaluate the effectiveness of injected poly-ethylene glycol hydrogel (SpaceOAR System) in creating space between the prostate and the anterior rectal wall. All patients received a baseline CT/MR scan and baseline IMRT treatment plan. Patients were randomized to receive hydrogel injection (n=20) or Control (n=10), followed by another CT/MR scan and treatment plan (single arc VMAT, 6 MV photons, 79.2 Gy, 44 fractions). Additional optimization structuresmore » were employed to constrain the dose to the rectum; specifically an avoidance structure to limit V75 <15%, and a control structure to limit the maximum relative dose <105% in the interface region of the anterior rectal wall and the prostate planning target volume. Dose volumetric data was analyzed for rectal volumes receiving 60 through 80 Gy. Results: Rectal dose reduction was observed in all patients who received the hydrogel. Volumetric analysis indicates a median rectal volume and (reduction from baseline plan) following spacer application of 4.9% (8.9%) at V60Gy, 3.8% (8.1%) at V65Gy, 2.5% (7.2%) at V70Gy, 1.6% (5.8%) at V75Gy, and 0.5% (2.5%) at V80Gy. Conclusion: Relative to planning without spacers, rectal dose constraints of 5%, 4%, 3%, 2%, 1% for V60, V65, V70, V75, and V80, should be obtainable when peri-rectal spacers are used. The combined effect of increased peri-rectal space provided by the hydrogel, with strict optimization objectives, resulted in reduced dose to the rectum. To maximize benefit, strict optimization objectives and reduced rectal dose constraints should be employed when creating plans for patients with perirectal spacers. Clinical Trial for SpaceOAR product conducted by Augmenix,Inc. The research site was paid to be a participating site.« less

MHI-148 Cyanine Dye Conjugated Chitosan Nanomicelle with NIR Light-Trigger Release Property as Cancer Targeting Theranostic Agent.

PubMed

Thomas, Reju George; Moon, Myeong Ju; Surendran, Suchithra Poilil; Park, Hyeong Ju; Park, In-Kyu; Lee, Byeong-Il; Jeong, Yong Yeon

2018-02-15

Paclitaxel (PTX) loaded hydrophobically modified glycol chitosan (HGC) micelle is biocompatible in nature, but it requires cancer targeting ability and stimuli release property for better efficiency. To improve tumor retention and drug release characteristic of HGC-PTX nanomicelles, we conjugated cancer targeting heptamethine dye, MHI-148, which acts as an optical imaging agent, targeting moiety and also trigger on-demand drug release on application of NIR 808 nm laser. The amine group of glycol chitosan modified with hydrophobic 5β-cholanic acid and the carboxyl group of MHI-148 were bonded by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide chemistry. Paclitaxel was loaded to MHI-HGC nanomicelle by an oil-in-water emulsion method, thereby forming MHI-HGC-PTX. Comparison of near infrared (NIR) dyes, MHI-148, and Flamma-774 conjugated to HGC showed higher accumulation for MHI-HGC in 4T1 tumor and 4T1 tumor spheroid. In vitro studies showed high accumulation of MHI-HGC-PTX in 4T1 and SCC7 cancer cell lines compared to NIH3T3 cell line. In vivo fluorescence imaging of the 4T1 and SCC7 tumor showed peak accumulation of MHI-HGC-PTX at day 1 and elimination from the body at day 6. MHI-HGC-PTX showed good photothermal heating ability (50.3 °C), even at a low concentration of 33 μg/ml in 1 W/cm 2 808 nm laser at 1 min time point. Tumor reduction studies in BALB/c nude mice with SCC7 tumor showed marked reduction in MHI-HGC-PTX in the PTT group combined with photothermal therapy compared to MHI-HGC-PTX in the group without PTT. MHI-HGC-PTX is a cancer theranostic agent with cancer targeting and optical imaging capability. Our studies also showed that it has cancer targeting property independent of tumor type and tumor reduction property by combined photothermal and chemotherapeutic effects.

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.

Simultaneous heat and mass transfer inside a vertical channel in evaporating a heated falling glycols liquid film

NASA Astrophysics Data System (ADS)

Nait Alla, Abderrahman; Feddaoui, M'barek; Meftah, Hicham

2015-12-01

The interactive effects of heat and mass transfer in the evaporation of ethylene and propylene glycol flowing as falling films on vertical channel was investigated. The liquid film falls along a left plate which is externally subjected to a uniform heat flux while the right plate is the dry wall and is kept thermally insulated. The model solves the coupled governing equations in both phases together with the boundary and interfacial conditions. The systems of equations obtained by using an implicit finite difference method are solved by Tridiagonal Matrix Algorithm. The influence of the inlet liquid flow, Reynolds number in the gas flow and the wall heat flux on the intensity of heat and mass transfers are examined. A comparison between the results obtained for studied glycols and water in the same conditions is made. The results indicate that water evaporates in more intense way in comparison to glycols and the increase of gas flow rate tends to improve slightly the evaporation.

The Causes of Blistering in Boat Building Materials

DTIC Science & Technology

1986-08-01

acrylate units (MET) Ethylene glycol (MET) Propylene glycol (MET) Neopentyl glycol (NET) Maleic acid or anhydride (unsaturated) (NET) lumaric acid...PROPYLENE GLYCOL OPA ORTHOPHTHALIC ACID VINYL - URETHANE BASED POLYESTER IqPG NEOPENTYL GLYCOL RESIN EG - ETHYLENE GLYCOL TMPD - 22,, - TRiMETHY...IPA Isophthalic acid WSN Low molecular weight water soluble material NPG Neopentyl glycol OPA Orthophthalio acid PG Propylene glycol MEKP Hethyl

Effect of l-lysine-assisted surface grafting for nano-hydroxyapatite on mechanical properties and in vitro bioactivity of poly(lactic acid-co-glycolic acid).

PubMed

Liuyun, Jiang; Lixin, Jiang; Chengdong, Xiong; Lijuan, Xu; Ye, Li

2016-01-01

It is promising and challenging to study surface modification for nano-hydroxyapatite to improve the dispersion and enhance the mechanical properties and bioactivity of poly(lactic acid-co-glycolic acid). In this paper, we designed an effective new surface grafting with the assist of l-lysine for nano-hydroxyapatite, and the nano-hydroxyapatite surface grafted with the assist of l-lysine (g-nano-hydroxyapatite) was incorporated into poly(lactic acid-co-glycolic acid) to develop a series of g-nano-hydroxyapatite/poly(lactic acid-co-glycolic acid) nano-composites. The surface modification reaction for nano-hydroxyapatite, the mechanical properties, and in vitro human osteoblast-like cell (MG-63) response were characterized and investigated by Fourier transformation infrared, thermal gravimetric analysis, dispersion test, electromechanical universal tester, differential scanning calorimeter measurements, and in vitro cells culture experiment. The results showed that the grafting amount on the surface of nano-hydroxyapatite was enhanced with the increase of l-lysine, and the dispersion of nano-hydroxyapatite was improved more, so that it brought about better promotion crystallization and more excellent mechanical enhancement effect for poly(lactic acid-co-glycolic acid), comparing with the unmodified nano-hydroxyapatite. Moreover, the cells' attachment and proliferation results confirmed that the incorporation of the g-nano-hydroxyapatite into poly(lactic acid-co-glycolic acid) exhibited better biocompatibility than poly(lactic acid-co-glycolic acid). The above results indicated that the new surface grafting with the assist of l-lysine for nano-hydroxyapatite was an ideal novel surface modification method, which brought about better mechanical enhancement effect and in vitro bioactivity for poly(lactic acid-co-glycolic acid) with adding higher g-nano-hydroxyapatite content, suggesting it had a great potential to be used as bone fracture internal fixation materials in future. © The Author(s) 2015.

Preparation and characterization of polyol assisted ultrafine Cu-Ni-Mg-Ca mixed ferrite via co-precipitation method

NASA Astrophysics Data System (ADS)

Boobalan, T.; Pavithradevi, S.; Suriyanarayanan, N.; Manivel Raja, M.; Ranjith Kumar, E.

2017-04-01

Nanocrystalline spinel ferrite of composition Cu0.2Ni0.2Mg0.2Ca0.4Fe2O4 is synthesized by wet hydroxyl co-precipitation method in ethylene glycol as chelating agent and sodium hydroxide as precipitator at pH 8. Ethylene glycol is utilized as the medium which serves as the dissolvable and in addition a complexing specialist. The synthesized particles are annealed at various temperatures. Thermogravimetric investigation affirms that at 280 °C ethylene glycol is dissipated totally and stable phase arrangement happens over 680 °C. FTIR spectra of as synthesized and annealed at 1050 °C recorded between 400 cm-1 and 4000 cm-1. Structural characterizations of all the samples are carried out by X-ray diffraction (XRD) technique. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) affirm that the particles are spherical and cubic shape with the crystallite size of 12 nm to 32 nm. Magnetic measurements are performed utilizing vibrating sample magnetometer at room temperature.

Hexagonal spherical Ln3+-doped NaGdF4: A facile double solvent hydrothermal synthesis and luminescent properties

NASA Astrophysics Data System (ADS)

Wu, Kelu; Huang, Zhuanzhuan; Yu, Qiao-He; Wang, Yi-Yan; Xia, Tian-Long

2017-04-01

Different sizes of hexagonal spherical NaGdF4:Eu3+ particles are synthesized via a facile hydrothermal method with the use of ethylene glycol (EG), propylene glycol (PG) or butylene glycol (BG) as another solvent. The particle size decreases with the addition of EG, PG or BG and the decreasing trend in BG/H2O system is significantly more than that in the other two systems. Meanwhile, results show that luminescent properties of NaGdF4:Eu3+ are enhanced along with the decrease of particle size. Besides, the energy transfer from Dy3+ to Eu3+ is directly observed in the PL spectra of NaGdF4:Eu3+/Dy3+.

Effects of external applications of No. 2 fuel oil on common eider eggs

USGS Publications Warehouse

Szaro, Robert C.; Albers, P.H.; Wolfe, Douglas A.

1977-01-01

Because eggs of marine birds may be exposed to oil adhering to the feathers of adult birds, a study was undertaken to determine the effects of oil contamination. Two hundred common eider eggs were divided into four experimental sets of 50 each. Two sets were treated with No. 2 fuel oil in amounts of 5 microliters to 20 microliters; a third with 20 microliters of propylene glycol, a neutral blocking agent. The fourth set served as a control. Hatching success was 96 percent for the eggs treated with 20 microliters propylene glycol, 96 percent for the controls and 92 percent for the eggs treated with 5 microliters oil hatched. Only 69 percent of the eggs treated with 20 microliters of oil survived - a significant reduction in hatchability (P 0.05). Mean Hatching weights for all sets were statistically equal. Thus, oil pollution may significantly increase embryonic mortality in marine birds.

The effect of using propylene glycol as a vehicle on the microhardness of mineral trioxide aggregate.

PubMed

Salem Milani, Amin; Banifatemeh, Alireza; Rahimi, Saeed; Jafarabadi, Mohammad Asghari

2015-01-01

While it has been proven that the handling properties of mineral trioxide aggregate (MTA) are improved upon mixing it with propylene glycol (PG), this study sought to evaluate how PG affects the microhardness of MTA in terms of setting quality. MTA was mixed with different proportions of distilled water (DW) and PG to prepare 5 groups (n = 30). The DW/PG percent proportions used in Groups 1-5 were 100/0, 80/20, 50/50, 20/80, and 0/100, respectively. The mixed MTA was condensed into acrylic molds. Half of the samples of each group were evaluated on Day 4, the other half on Day 28. The results indicated that PG reduces the microhardness of MTA, thus adversely affecting its setting process. Group 2 (80% DW/20% PG) best improved the handling of MTA without a significant reduction in setting quality.

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.

Preparation and characterization of functional material based on hybrid polymer composites

NASA Astrophysics Data System (ADS)

Agusu, La; Amiruddin; Taswito, Chen Chen; Herdianto; Zamrun, Muh.

2016-08-01

The microstructures and properties of hybrid polymer composites based on polyaniline (PANi)/γ-Fe2O3 nanoparticles/TiO2/carbon have been investigated for multifunctional applications such as heavy metal removal and initial study for radar absorbing material application. γ-Fe2O3 nanoparticles with spherical shape were synthetized by a coprecipitation method from iron sand. By activating the polyethylene glycol (PEG-400) coated carbon of coconut shell, the homogenous shape and size of carbon was achieved. Then, γ- Fe2O3, TiO2, and carbon were mixed with PANi by an in situ polymerization method at low temperature 0-5 oC. Characterization process involved XRD, SEM, FTIR, VSM, and DC conductivity measurements. For radar absorber application, the functionalized polymer composites showed good electrical conductivity 0.45 S/cm to absorb the incoming electromagnetic energy. An efficient and effective reduction of Pb2+ ion from the water has been achieved by using this material.

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

HNO₃-assisted polyol synthesis of ultralarge single-crystalline Ag microplates and their far propagation length of surface plasmon polariton.

PubMed

Chang, Cheng-Wei; Lin, Fan-Cheng; Chiu, Chun-Ya; Su, Chung-Yi; Huang, Jer-Shing; Perng, Tsong-Pyng; Yen, Ta-Jen

2014-07-23

We developed a HNO3-assisted polyol reduction method to synthesize ultralarge single-crystalline Ag microplates routinely. The edge length of the synthesized Ag microplates reaches 50 μm, and their top facets are (111). The mechanism for dramatically enlarging single-crystalline Ag structure stems from a series of competitive anisotropic growths, primarily governed by carefully tuning the adsorption of Ag(0) by ethylene glycol and the desorption of Ag(0) by a cyanide ion on Ag(100). Finally, we measured the propagation length of surface plasmon polaritons along the air/Ag interface under 534 nm laser excitation. Our single-crystalline Ag microplate exhibited a propagation length (11.22 μm) considerably greater than that of the conventional E-gun deposited Ag thin film (5.27 μm).

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

Kubouchi, Masatoshi; Hojo, Hidemitsu

The thermal shock resistance of epoxy resin specimens toughened with carboxy-terminated poly(butadiene-acrylonitrile) (CTBN) and poly-glycol were tested using a new notched disk-type specimen. The new thermal shock testing method consists of quenching a notched disk-type specimen and applying a theoretical analysis to the test results to determine crack propagation conditions. For both toughened epoxy resins, this test method evaluated improvements in thermal shock resistance. The thermal shock resistance of epoxy resin toughened with CTBN exhibited a maximum at a 35 parts per hundred resin content of CTBN. The epoxy resin toughened with polyglycol exhibited improved thermal shock resistance with increasingmore » glycol content. 7 refs., 14 figs., 1 tab.« less

Relationship of the method of addition and temperature of cryoprotective agents to the fertilizing capacity of cooled chicken spermatozoa.

PubMed

Sexton, T J

1975-05-01

Three experiments were conducted to determine the relationship of the method of adding (fraction or bulk) and/or holding temperature (41 degrees, 25 degrees, 10 degrees) of glycerol, dimethylsulfoxide or ethylene glycol to the fertilizing capacity of chicken spermatozoa during cooling. No significant effect on fertility was observed when sperm were washed, suspended without dilution in phosphate buffer or milk and cooled to 15 degrees in 30 min. With phosphate buffer as the medium, fertility was comparable with that of the control only when glycol was maintained at 41 degrees or 25 degrees prior to addition in fractions (3 equal parts at 10 min. intervals). Similar effects were observed when 4% DMSO at 25 degrees was added in bulk after cooling. However, when DMSO was added to sperm suspended in milk, fertility was significantly reduced regardless of treatment. None of the methods were successful in eliminating the contraceptive action of glycerol. The results indicate that a number of in vitro techniques can be used to maintain the fertilizing capacity of chicken spermatozoa in the presence of 4% ethylene glycol or DMSO.

Reductions in DNAPL Longevity through Biological Flux Enhancement

DTIC Science & Technology

2009-01-01

3 Phosphorus 2 Calcium 111 Magnesium 11 Sulfur 47 Bioavailable iron 31 Total iron 198 Porosity 0.32 Conductivity 0.97 mmohs cm-1 Organic...acetate, propionate, and lactate were analyzed by filtering aqueous samples (2.7 mL) through a syringe filter (0.22 μm) containing 0.3 M oxalic acid...acid Nitric acid, glycol, peroxides, permanganates Acetone Conc. nitric and sulfuric acids Ammonia, anhydrous Halogens, calcium hypochlorite (bleach

Development and Testing of a Colorimetric 96 Well Plate Assay for the Determination of HD Hydrolysis Rate in Various Formulations

DTIC Science & Technology

2005-01-01

Cold Foam 1% ethylene glycol 1% benzalkonium chloride 1% polyvinylpolypyrrolidone 1% Brij 58 1% Benzyldimethyl tetradecyl ammonium chloride dihydrate...described in this report was authorized by the Defense Threat Reduction Agency. This work was started in December 2003 and completed in March 2004. The...LITERA TURE CITED ..................................................................................... 15 5 FIGURES 1. Rates of Chloride Release in

Compartmentation Studies on Spinach Leaf Peroxisomes 1

PubMed Central

Heupel, Ralf; Markgraf, Therese; Robinson, David G.; Heldt, Hans Walter

1991-01-01

In concurrence with earlier results, the following enzymes showed latency in intact spinach (Spinacia oleracea L.) leaf peroxisomes: malate dehydrogenase (89%), hydroxypyruvate reductase (85%), serine glyoxylate aminotransferase (75%), glutamate glyoxylate aminotransferase (41%), and catalase (70%). In contrast, glycolate oxidase was not latent. Aging of peroxisomes for several hours resulted in a reduction in latency accompanied by a partial solubilization of the above mentioned enzymes. The extent of enzyme solubilization was different, being highest with glutamate glyoxylate aminotransferase and lowest with malate dehydrogenase. Osmotic shock resulted in only a partial reduction of enzyme latency. Electron microscopy revealed that the osmotically shocked peroxisomes remained compact, with smaller particle size and pleomorphic morphology but without a continuous boundary membrane. Neither in intact nor in osmotically shocked peroxisomes was a lag phase observed in the formation of glycerate upon the addition of glycolate, serine, malate, and NAD. Apparently, the intermediates, glyoxylate, hydroxypyruvate, and NADH, were confined within the peroxisomal matrix in such a way that they did not readily leak out into the surrounding medium. We conclude that the observed compartmentation of peroxisomal metabolism is not due to the peroxisomal boundary membrane as a permeability barrier, but is a function of the structural arrangement of enzymes in the peroxisomal matrix allowing metabolite channeling. ImagesFigure 3 PMID:16668283

Correlation between product purity and process parameters for the synthesis of Cu2ZnSnS4 nanoparticles using microwave irradiation

NASA Astrophysics Data System (ADS)

Ahmad, R.; Nicholson, K. S.; Nawaz, Q.; Peukert, W.; Distaso, M.

2017-07-01

Kesterites (CZT(S,Se)4) emerged as a favourable photovoltaic material, leading to solar cell efficiencies as high as 12.7%. The development of sustainable roll-to-roll printing processes that make use of Cu2ZnSnS4 (CZTS) nanoparticle inks requires the proper design of synthetic approaches and the understanding of the relation between process parameters and product purity. In the current paper, we developed this relationship by calculating a specific energy factor. A microwave-assisted synthetic method that operates at atmospheric pressure and makes use of eco-friendly solvents is established. Four solvents, i.e. ethylene glycol (EG), diethylene glycol (di-EG), triethylene glycol (tri-EG) and tetraethylene glycol (tet-EG) are compared and the temperature during the reaction is assessed by two different methods. In particular, two by-products have been identified, i.e. Cu2 - x S and a hexagonal phase. We show that the variation of reaction parameters such as power irradiation, type of solvent and precursor concentration influences the nanoparticles' sizes (from 12 to 6 nm) and also the temperature-time profile of reaction which, in turn, can be related to phase purity of CZTS nanoparticles. The results suggest that the product purity scales with the specific energy factor providing a useful tool to a rational design of high-quality CZTS nanoparticles.

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.

The use of fillers and botulinum toxin type A in combination with superficial glycolic acid (alpha-hydroxy acid) peels: optimizing injection therapy with the skin-smoothing properties of peels.

PubMed

Rendon, Marta I; Effron, Cheryl; Edison, Brenda L

2007-01-01

There are many procedures that a physician may utilize to improve the appearance and quality of the skin. Combining procedures can enhance the overall result and lead to increased patient satisfaction. Thus, it is important to choose procedures that will complement each other. Fillers or botulinum toxin type A (BTX-A) can plump the skin and smooth lines and wrinkles but will do little for uneven tone, skin laxity, or radiance and clarity. These signs of aging can be addressed with superficial glycolic acid peels. Methods of combining injectable compounds with superficial glycolic acid peels were discussed at a dermatologist roundtable event and are summarized in this article.

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...

Crystallization of toxic glycol solvates of rifampin from glycerin and propylene glycol contaminated with ethylene glycol or diethylene glycol.

PubMed

de Villiers, Melgardt M; Caira, Mino R; Li, Jinjing; Strydom, Schalk J; Bourne, Susan A; Liebenberg, Wilna

2011-06-06

This study was initiated when it was suspected that syringe blockage experienced upon administration of a compounded rifampin suspension was caused by the recrystallization of toxic glycol solvates of the drug. Single crystal X-ray structure analysis, powder X-ray diffraction, thermal analysis and gas chromatography were used to identify the ethylene glycol in the solvate crystals recovered from the suspension. Controlled crystallization and solubility studies were used to determine the ease with which toxic glycol solvates crystallized from glycerin and propylene glycol contaminated with either ethylene or diethylene glycol. The single crystal structures of two distinct ethylene glycol solvates of rifampin were solved while thermal analysis, GC analysis and solubility studies confirmed that diethylene glycol solvates of the drug also crystallized. Controlled crystallization studies showed that crystallization of the rifampin solvates from glycerin and propylene glycol depended on the level of contamination and changes in the solubility of the drug in the contaminated solvents. Although the exact source of the ethylene glycol found in the compounded rifampin suspension is not known, the results of this study show how important it is to ensure that the drug and excipients comply with pharmacopeial or FDA standards.

Amphiphilic graft polymer with reduction breakable main chain prepared via click polymerization and grafting onto

NASA Astrophysics Data System (ADS)

Zhang, Xiaojin; Dai, Yu

2018-06-01

Amphiphilic graft polymer PSS- g-Pal/PEG with reduction breakable main chain was synthesized via click polymerization of dialkynyl (containing disulfide bond) and diazide (containing pendant diol) and one-pot grafting onto of hydrophobic palmitate (Pal) and hydrophilic methoxy poly(ethylene glycol) (PEG). PSS- g-Pal/PEG is able to form polymeric micelles by self-assembly in water via dialysis. Polymeric micelles are nano-sized spheres and the particle size is approximately 70 nm. Of note, polymeric micelles are reduction-responsive owing to the disulfide bonds in main chain of PSS- g-Pal/PEG. Therefore, polymeric micelles prepared from amphiphilic graft polymer PSS- g-Pal/PEG are able to fast release the drugs in the presence of the reducing agents such as DL-dithiothreitol (DTT).

Development of Drag Reducing Polymer of FDR-SPC

NASA Astrophysics Data System (ADS)

Lee, Inwon; Park, Hyun; Chun, Ho Hwan

2015-11-01

In this study, a novel FDR-SPC (Frictional Drag Reduction Self-Polishing Copolymer) is first synthesized in this study. The drag reducing functional radical such as PEGMA (Poly(ethylene) glycol methacrylate) has been utilized to participate in the synthesis process of the SPC. The release mechanism of drag reducing radical is accounted for the hydrolysis reaction between the FDR-SPC and seawater. The types of the baseline SPC monomers, the molecular weight and the mole fraction of PEGMA were varied in the synthesis process. The resulting SPCs were coated to the substrate plates for the subsequent hydrodynamic test for skin friction measurement. A significant reduction in Reynolds stress was observed in a range of specimen, with the maximum drag reduction being 15.9% relative to the smooth surface for PRD3-1.

40 CFR 414.70 - Applicability; description of the bulk organic chemicals subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Monomethyl Ether *Dimer Acids Dioxane Ethane Ethylene Glycol Monophenyl Ether *Ethoxylates, Misc. Ethylene Glycol Dimethyl Ether Ethylene Glycol Monobutyl Ether Ethylene Glycol Monoethyl Ether Ethylene Glycol...

Waterborne Polyurethane Coatings with Covalently Linked Black Dye Sudan Black B

PubMed Central

Sun, Wei; Xu, Haiyan; Xu, Fei

2017-01-01

Colored waterborne polyurethanes have been widely used in paintings, leathers, textiles, and coatings. Here, a series of black waterborne polyurethanes (WPUs) with different ratios of black dye, Sudan Black B (SDB), were prepared by step-growth polymerization. WPU emulsions as obtained exhibit low particle sizes and remarkable storage stability at the same time. At different dye loadings, essential structural, statistical and thermal properties are characterized. FTIR (fourier transform infrared) spectra indicate that SDB is covalently linked into waterborne polyurethane chains. All of the WPUs with covalently linked SDB show better color fastness and resistance of thermal migration than those with SDB mixed physically. Besides, WPUs incorporated SDB covalently with different polymeric diols, polytetramethylene ether glycol (PTMG), polypropylene glycol (PPG), poly-1, 4-butylene adipate glycol (PBA) and polycaprolactone glycol (PCL), were prepared to obtain different properties to cater to a variety of practical demands. By a spraying method, the black WPUs can be directly used as metal coatings without complex dyeing process by simply mixing coating additive and other waterborne resins, which exhibit excellent coating performance. PMID:29143785

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)).

Effect of compositions in nanostructured lipid carriers (NLC) on skin hydration and occlusion.

PubMed

Loo, Ch; Basri, M; Ismail, R; Lau, Hln; Tejo, Ba; Kanthimathi, Ms; Hassan, Ha; Choo, Ym

2013-01-01

To study the effects of varying lipid concentrations, lipid and oil ratio, and the addition of propylene glycol and lecithin on the long-term physical stability of nanostructured lipid nanocarriers (NLC), skin hydration, and transepidermal water loss. The various NLC formulations (A1-A5) were prepared and their particle size, zeta potential, viscosity, and stability were analyzed. The formulations were applied on the forearms of the 20 female volunteers (one forearm of each volunteer was left untreated as a control). The subjects stayed for 30 minutes in a conditioned room with their forearms uncovered to let the skin adapt to the temperature (22°C ± 2°C) and humidity (50% ± 2%) of the room. Skin hydration and skin occlusion were recorded at day one (before treatment) and day seven (after treatment). Three measurements for skin hydration and skin occlusion were performed in each testing area. NLC formulations with the highest lipid concentration, highest solid lipid concentration, and additional propylene glycol (formulations A1, A2, and A5) showed higher physical stability than other formulations. The addition of propylene glycol into an NLC system helped to reduce the particle size of the NLC and enhanced its long-term physical stability. All the NLC formulations were found to significantly increase skin hydration compared to the untreated controls within 7 days. All NLC formulations exhibited occlusive properties as they reduced the transepidermal water loss within 7 days. This effect was more pronounced with the addition of propylene glycol or lecithin into an NLC formulation, whereby at least 60% reduction in transepidermal water loss was observed. NLCs with high lipid content, solid lipid content, phospholipid, and lecithin are a highly effective cosmetic delivery system for cosmetic topical applications that are designed to boost skin hydration.

Randomized clinical efficacy of superficial peeling with 85% lactic acid versus 70% glycolic acid.

PubMed

Prestes, Paula Souza; Oliveira, Márcia Motta Maia de; Leonardi, Gislaine Ricci

2013-01-01

Peeling is a procedure which aims to accelerate the process of skin exfoliation. Development of formulations containing lactic acid at 85% or glycolic acid at 70% and the evaluation of these formulations on clinical efficacy in reduction of fine wrinkles. Preliminary stability tests were carried out and an in vivo study was performed with three groups with 9 representatives each. One was the control group, which used only sunscreen; another one used lactic acid+sunscreen, and the last group used acid glycolic+sunscreen. Clinical efficacy was assessed with a CCD color microscope, through the digitization of images before and after treatment. The applications were carried out by a dermatologist, once a mont h every 30 days, during 3 months. The area with wrinkles was calculated by planimetry point counting, in accordance with Mandarin-de-Lacerda. The formulations were stable in the visual and Ph evaluation. There was no improvement in the control group; for lactic acid, there was significant improvement after the second peeling application on the outer lateral area of the right eye and after the third application on the outer lateral area of the left eye. For the glycolic acid group, there was significant improvement in the outer lateral area of the left eye after the first application, and of the right eye region, after three applications. The formulations used must be kept under refrigeration and should be manipulated every 30 days. Both peelings were effective in reducing fine wrinkles of the outer lateral eye area after three applications (p ≤ 0.05%). It was observed that peeling efficacy in the external-lateral region of one eye might be different compared with that in skin of the external-lateral region of the other eye, relative to the speed of skin improvement.

21 CFR 172.858 - Propylene glycol alginate.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Propylene glycol alginate. 172.858 Section 172.858... Propylene glycol alginate. The food additive propylene glycol alginate (CAS Reg. No. 9005-37-2) may be used... the act: (1) The name of the additive, “propylene glycol alginate” or “propylene glycol ester of...

76 FR 38026 - Diethylene Glycol Mono Butyl Ether; Exemption From the Requirement of a Tolerance

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-29

... chemicals. Immunotoxicity studies were available for ethylene glycol mono butyl ether, also a glycol ether... the glycol ether class of chemicals which include structurally similar chemicals ethylene glycol and... potential to cause cancer. Based on the lack of evidence of carcinogenicity potential for ethylene glycol...

Apollo experience report: Detection and minimization of ignition hazards from water/glycol contamination of silver-clad electrical circuitry

NASA Technical Reports Server (NTRS)

Downs, W. R.

1976-01-01

The potential flammability hazard when a water/glycol solution contacts defectively insulated silver-clad copper circuitry or electrical components carrying a direct current is described. The chemical reactions and means for detecting them are explained. Methods for detecting and cleaning contaminated areas and the use of inhibitors to arrest chemical reactivity are also explained. Preventive measures to minimize hazards are given. Photomicrographs of the chemical reactions occurring on silver clad wires are also included.

An evaluation of microbial growth and corrosion of 316L SS in glycol/seawater mixtures

NASA Technical Reports Server (NTRS)

Lee, Jason S.; Ray, Richard I.; Lowe, Kristine L.; Jones-Meehan, Joanne; Little, Brenda J.

2003-01-01

Glycol/seawater mixtures containing > 50% glycol inhibit corrosion of 316L stainless steel and do not support bacterial growth. The results indicate bacteria are able to use low concentrations of glycol (10%) as a growth medium, but bacterial growth decreased with increasing glycol concentration. Pitting potential, determined by anodic polarization, was used to evaluate susceptibility of 316L SS to corrosion in seawater-contaminated glycol. Mixture containing a minimum concentration of 50% propylene glycol-based coolant inhibited pitting corrosion. A slightly higher minimum concentration (55%) was needed for corrosion protection in ethylene glycol mixtures.

Material compatibility evaluation for DWPF nitric-glycolic acid-literature review

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

Mickalonis, J.; Skidmore, E.

2013-06-01

Glycolic acid is being evaluated as an alternative for formic and nitric acid in the DWPF flowsheet. Demonstration testing and modeling for this new flowsheet has shown that glycolic acid and glycolate has a potential to remain in certain streams generated during the production of the nuclear waste glass. A literature review was conducted to assess the impact of glycolic acid on the corrosion of the materials of construction for the DWPF facility as well as facilities downstream which may have residual glycolic acid and glycolates present. The literature data was limited to solutions containing principally glycolic acid.

Five-year review of a UK 24 hour testing service for plasma ethylene glycol and diethylene glycol.

PubMed

Ford, Loretta T; Berg, Jonathan D

2016-07-01

We present a 5-year review of our UK service for plasma ethylene glycol and diethylene glycol determination in cases of acute poisoning. Ethylene glycol and diethylene glycol have been measured on all samples received for screening for toxicity by gas chromatography-flame ionization detection over a five-year period. A detailed audit of the results has been undertaken. In this period, we received 811 requests, 56% were for first-time screening and 44% repeat analysis where a positive sample has already been received. Of the first-time screen samples, 33.5% screened positive for glycol poisoning. The mean positive ethylene glycol concentration was 1204 mg/L (range 31 to 8666 mg/L). Diethylene glycol was present in 14% of ethylene glycol positive samples but never found alone. The data presented here suggest it is not essential to measure diethylene glycol since its inclusion is rarely likely to change patient management. © The Author(s) 2015.

Preparation of Copper Telluride Films by Co-Reduction of Cu(I) and Te(IV) Ions in Choline Chloride: Ethylene Glycol Ionic Liquid

NASA Astrophysics Data System (ADS)

Golgovici, Florentina; Catrangiu, Adriana-Simona; Stoian, Andrei Bogdan; Anicai, Liana; Visan, Teodor

2016-07-01

Cathodic processes of direct co-reduction of Cu+ and Te4+ ions on Pt electrode at 60°C were investigated using cyclic voltammetry and electrochemical impedance spectroscopy techniques. The ionic liquid as background electrolyte consisted of a mixture of choline chloride and ethylene glycol (ChCl-EG 1:2 mol ratio) in which 5-20 mM CuCl and 8 mM TeO2 were dissolved. The voltammograms exhibited the following successive cathodic processes: Cu2+/Cu+ reduction, Te underpotential deposition, simultaneous deposition of Cu metal and CuTe compound, and deposition of Te-rich CuTe compound at the most negative potentials (from -0.5 V to -0.8 V). Corresponding dissolution or oxidation peaks were recorded on the anodic branch. The voltammetric results were confirmed by electrochemical impedance spectra. Copper telluride films have been synthesized on platinum substrate via potentiostatic electrodeposition at 60°C. It was found from atomic force microscopy that CuTe film samples prepared from ChCl-EG + 5 mM CuCl + 8 mM TeO2 ionic liquid have high growth rates. The x-ray diffraction patterns of the deposited films from ChCl-EG + 10 mM CuCl + 8 mM TeO2 ionic liquid indicated the presence of a Cu2Te phase for film deposited at -0.7 V and a Cu0.656Te0.344 phase for film deposited at -0.6 V.

Dosimetric effects of polyethylene glycol surface coatings on gold nanoparticle radiosensitization

NASA Astrophysics Data System (ADS)

Koger, B.; Kirkby, C.

2017-11-01

One of the main appeals of using gold nanoparticles (GNPs) as radiosensitizers is that their surface coatings can be altered to manipulate their pharmacokinetic properties. However, Monte Carlo studies of GNP dosimetry tend to neglect these coatings, potentially changing the dosimetric results. This study quantifies the dosimetric effects of including a polyethylene glycol (PEG) surface coating on GNPs over both nanoscopic and microscopic ranges. Two dosimetric scales were explored using PENELOPE Monte Carlo simulations. In microscopic simulations, 500-1000 GNPs, with and without coatings, were placed in cavities of side lengths 0.8-4 µm, and the reduction of dose deposited to surrounding medium within these volumes due to the coating was quantified. Including PEG surface coatings of up to 20 nm thickness resulted in reductions of up to 7.5%, 4.0%, and 2.0% for GNP diameters of 10, 20, and 50 nm, respectively. Nanoscopic simulations observed the dose falloff in the first 500 nm surrounding a single GNP both with and without surface coatings of various thicknesses. Over the first 500 nm surrounding a single GNP, the presence of a PEG surface coating reduced dose by 5-26%, 8-28%, 8-30%, and 8-34% for 2, 10, 20, and 50 nm diameter GNPs, respectively, for various energies and coating thicknesses. Reductions in dose enhancement due to the inclusion of a GNP surface coating are non-negligible and should be taken into consideration when investigating GNP dose enhancement. Further studies should be carried out to investigate the biological effects of these coatings.

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.

Synthesis and optical properties of silver nanoparticles

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

Singh, Jaiveer; Kaurav, Netram, E-mail: netramkaurav@yahoo.co.uk; Choudhary, K. K.

The preparation of stable, uniform silver nanoparticles by reduction of silver acetate by ethylene glycol (EG) is reported in the present paper. It is a simple process of recent interest for obtaining silver nanoparticles. The samples were characterized by X-Ray diffraction (XRD), which reveals an average particle size (D) of 38 nm. The UV/Vis spectra show that an absorption peak, occurring due to surface plasmon resonance (SPR), exists at 319 nm.

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.

Synthesis and characterization of PEO-PCL-PEO triblock copolymers: effects of the PCL chain length on the physical property of W(1)/O/W(2) multiple emulsions.

PubMed

Cho, Heui Kyoung; Cho, Kwang Soo; Cho, Jin Hun; Choi, Sung Wook; Kim, Jung Hyun; Cheong, In Woo

2008-08-01

A series of poly(ethylene glycol)-block-poly(epsilon-caprolactone)-block-poly(ethylene glycol) (PEO-PCL-PEO) triblock copolymers were prepared and then used for the investigation of the effects of the ratio of epsilon-caprolactone to poly(ethylene glycol) (i.e., [CL]/[EO]) on the physical properties of water-in-oil-in-water (W(1)/O/W(2)) multiple emulsions containing a model reagent, ascorbic acid-2-glucoside (AA2G). In the synthesis, the [CL]/[EO] was varied from 0.11 to 0.31. The molecular weights and compositions of PEO-PCL-PEO were determined by GPC and (1)H NMR analyses. Thermal behavior and crystal formation were studied by DSC, XRD, FT-IR, and polarized optical microscopy (POM). Aggregate behavior of PEO-PCL-PEO was confirmed by DLS, UV, and (1)H NMR. Morphology and relative stiffness of the W(1)/O/W(2) multiple emulsions in the presence of PEO-PCL-PEO were studied by confocal laser scanning microscopy (CLSM) and rheometer. Variation in the [CL]/[EO] significantly affects the crystalline temperature and spherulite morphology of PEO-PCL-PEO. As the [CL]/[EO] increases, the CMCs of PEO-PCL-PEO decreases and the slope of aggregate size reduction against the copolymer concentration becomes steeper except for the lowest [CL]/[EO] value of PEO-PCL-PEO (i.e., P-222). P-222 significantly increases the viscosity of continuous (W(2)) phase, which implies the copolymer would exist in the W(2) phase. On the other hand, the triblock copolymers with relatively high [CL]/[EO] ratios mainly contribute to the size reduction of multiple emulsions and the formation of a firm wall structure. The particle size of the multiple emulsion decreases and the elastic modulus increased as [CL]/[EO] increases, confirmed by microscopic and rheometric analyses.

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.

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.

Propylene glycol accumulation in critically ill patients receiving continuous intravenous lorazepam infusions.

PubMed

Horinek, Erica L; Kiser, Tyree H; Fish, Douglas N; MacLaren, Robert

2009-12-01

Lorazepam is recommended by the Society of Critical Care Medicine as the preferred agent for sedation of critically ill patients. Intravenous lorazepam contains propylene glycol, which has been associated with toxicity when high doses of lorazepam are administered. To evaluate the accumulation of propylene glycol in critically ill patients receiving lorazepam by continuous infusion and determine factors associated with propylene glycol concentration. A 6-month, retrospective, safety assessment was conducted of adults admitted to the medical intensive care unit who were receiving lorazepam by continuous infusion for 12 hours or more. Propylene glycol serum concentrations were obtained 24-48 hours after continuous-infusion lorazepam was initiated and every 3-5 days thereafter. Propylene glycol accumulation was defined as concentrations of 25 mg/dL or more. Groups with and without propylene glycol accumulation were compared and factors associated with propylene glycol concentration were determined using multivariate correlation regression analyses. Forty-eight propylene glycol serum samples were obtained from 33 patients. Fourteen (42%) patients had propylene glycol accumulation, representing 23 (48%) serum samples. Univariate analyses showed the following factors were related to propylene glycol accumulation: baseline renal dysfunction, presence of alcohol withdrawal, sex, age, Acute Physiology and Chronic Health Evaluation (APACHE II) score, rate of lorazepam continuous infusion, and 24-hour lorazepam dose. Multivariate linear regression modeling demonstrated that propylene glycol concentration was strongly associated with the continuous infusion rate and 24-hour dose (adjusted r(2) > or = 0.77; p < 0.001). Independent correlation analyses showed that these 2 variables were so strongly associated with propylene glycol concentration (r(2) > or = 0.71; p < 0.001) that they alone predicted propylene glycol concentration. Seven (21%) patients developed renal dysfunction after continuous-infusion lorazepam was initiated, but associated causes were indeterminable. Other possible propylene glycol-associated adverse effects were not observed. The continuous infusion rate and cumulative 24-hour lorazepam dose are strongly associated with and independently predict propylene glycol concentrations. Despite the absence of confirmed propylene glycol-associated adverse effects, clinicians should be aware that propylene glycol accumulation may occur with continuous-infusion lorazepam.

Time-weighted average sampling of airborne propylene glycol ethers by a solid-phase microextraction device.

PubMed

Shih, H C; Tsai, S W; Kuo, C H

2012-01-01

A solid-phase microextraction (SPME) device was used as a diffusive sampler for airborne propylene glycol ethers (PGEs), including propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), and dipropylene glycol monomethyl ether (DPGME). Carboxen-polydimethylsiloxane (CAR/PDMS) SPME fiber was selected for this study. A polytetrafluoroethylene (PTFE) tubing was used as the holder, and the SPME fiber assembly was inserted into the tubing as a diffusive sampler. The diffusion path length and area of the sampler were 0.3 cm and 0.00086 cm(2), respectively. The theoretical sampling constants at 30°C and 1 atm for PGME, PGMEA, and DPGME were 1.50 × 10(-2), 1.23 × 10(-2) and 1.14 × 10(-2) cm(3) min(-1), respectively. For evaluations, known concentrations of PGEs around the threshold limit values/time-weighted average with specific relative humidities (10% and 80%) were generated both by the air bag method and the dynamic generation system, while 15, 30, 60, 120, and 240 min were selected as the time periods for vapor exposures. Comparisons of the SPME diffusive sampling method to Occupational Safety and Health Administration (OSHA) organic Method 99 were performed side-by-side in an exposure chamber at 30°C for PGME. A gas chromatography/flame ionization detector (GC/FID) was used for sample analysis. The experimental sampling constants of the sampler at 30°C were (6.93 ± 0.12) × 10(-1), (4.72 ± 0.03) × 10(-1), and (3.29 ± 0.20) × 10(-1) cm(3) min(-1) for PGME, PGMEA, and DPGME, respectively. The adsorption of chemicals on the stainless steel needle of the SPME fiber was suspected to be one of the reasons why significant differences between theoretical and experimental sampling rates were observed. Correlations between the results for PGME from both SPME device and OSHA organic Method 99 were linear (r = 0.9984) and consistent (slope = 0.97 ± 0.03). Face velocity (0-0.18 m/s) also proved to have no effects on the sampler. However, the effects of temperature and humidity have been observed. Therefore, adjustments of experimental sampling constants at different environmental conditions will be necessary.

Tin-oxide-coated single-walled carbon nanotube bundles supporting platinum electrocatalysts for direct ethanol fuel cells.

PubMed

Hsu, Ryan S; Higgins, Drew; Chen, Zhongwei

2010-04-23

Novel tin-oxide (SnO(2))-coated single-walled carbon nanotube (SWNT) bundles supporting platinum (Pt) electrocatalysts for ethanol oxidation were developed for direct ethanol fuel cells. SnO(2)-coated SWNT (SnO(2)-SWNT) bundles were synthesized by a simple chemical-solution route. SnO(2)-SWNT bundles supporting Pt (Pt/SnO(2)-SWNTs) electrocatalysts and SWNT-supported Pt (Pt/SWNT) electrocatalysts were prepared by an ethylene glycol reduction method. The catalysts were physically characterized using TGA, XRD and TEM and electrochemically evaluated through cyclic voltammetry experiments. The Pt/SnO(2)-SWNTs showed greatly enhanced electrocatalytic activity for ethanol oxidation in acid medium, compared to the Pt/SWNT. The optimal SnO(2) loading of Pt/SnO(2)-SWNT catalysts with respect to specific catalytic activity for ethanol oxidation was also investigated.

Enhanced wettability of SU-8 photoresist through a photografting procedure for bioanalytical device applications

PubMed Central

Gao, Zhan; Henthorn, David B.; Kim, Chang-Soo

2009-01-01

In this work, we detail a method whereby a polymeric hydrogel layer is grafted to the negative tone photoresist SU-8 in order to improve its wettability. A photoinitiator is first immobilized on freshly prepared SU-8 samples, acting as the starting point for various surface modifications strategies. Grafting of a 2-hydroxyethylmethacrylate-based hydrogel from the SU-8 surface resulted in the reduction of the static contact angle of a water droplet from 79 ± 1° to 36 ± 1°, while addition of a poly(ethylene glycol)-rich hydrogel layer resulted in further improvement (8 ± 1°). Wettability is greatly enhanced after 30 minutes of polymerization, with a continued but more gradual decrease in contact angle up to approximately 50 minutes. Hydrogel formation is triggered by exposure to UV irradiation, allowing for the formation of photopatterned structures using existing photolithographic techniques. PMID:19756177

Facile fabrication of high-quality Ag/PS coaxial nanocables based on the mixed mode of soft/hard templates

NASA Astrophysics Data System (ADS)

Wan, Mimi; Zhao, Wenbo; Peng, Fang; Wang, Qi; Xu, Ping; Mao, Chun; Shen, Jian

2016-08-01

A new kind of high-quality Ag/PS coaxial nanocables can be facilely synthesized by using soft/hard templates method. In order to effectively introduce Ag sources into porous polystyrene (PS) nanotubes which were trapped in porous anodic aluminum oxide (AAO) hard template, Pluronic F127 (F127) was used as guiding agent, soft template and reductant. Meanwhile, ethylene glycol solution was also used as solvent and co-reducing agent to assist in the formation of silver nanowires. The influences of concentration of F127 and reducing reaction time on the formation of Ag/PS coaxial nanocables were discussed. Results indicated that the high-quality Ag/PS coaxial nanocables can be obtained by the mixed mode of soft/hard templates under optimized conditions. This strategy is expected to be extended to design more metal/polymer coaxial nanocables for the benefit of creation of complex and functional nanoarchitectures and components.

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

Solution of Azelaic Acid (20%), Resorcinol (10%) and Phytic Acid (6%) Versus Glycolic Acid (50%) Peeling Agent in the Treatment of Female Patients with Facial Melasma

PubMed Central

Faghihi, Gita; Taheri, Azam; Shahmoradi, Zabihollah; Nilforoushzadeh, Mohammad Ali

2017-01-01

Background: Melasma, a common acquired disorder of hyperpigmentation, especially in women, is often resistant to therapy. This study was aimed to evaluate the efficacy and safety of azelaic acid, resorcinol and phytic acid solution in chemical peeling of melasma in comparison to 50% glycolic acid. Materials and Methods: This clinical trial was performed, on 42 female patients with bilateral melasma. Severity of melasma was assessed by melasma area and severity index (MASI). Combination of (20% azelaic acid + 10% resorcinol + 6% phytic acid) was used as a new peeling agent on the right side of the face and 50% glycolic acid on the left side every 2 weeks for 6 times. Follow-up was carried out for 3 months after the last session. Any decrease in MASI score and unwanted complications following peeling were evaluated and compared during the trial. Results: Patients showed marked improvement as calculated with MASI score before and after treatment in both sides of the face. The efficacy of combination formula (azelaic acid, resorcinol and phytic acid) was similar to glycolic acid, but with fewer complications. There was no statistically difference in improvement between two groups (P > 0.05). However, the patient's discomfort following procedures was significantly lower with azelaic acid, resorcinol and phytic compared with the glycolic acid peels (P < 0.05) and there was the same duration in the beginning of the therapeutic response in both groups. Conclusion: Results showed that triple-combination was found to be an effective and safe peeling agent in the treatment of melasma and it was as effective as 50% glycolic acid peel. PMID:28299301

Membrane permeability of the human granulocyte to water, dimethyl sulfoxide, glycerol, propylene glycol and ethylene glycol.

PubMed

Vian, Alex M; Higgins, Adam Z

2014-02-01

Granulocytes are currently transfused as soon as possible after collection because they rapidly deteriorate after being removed from the body. This short shelf life complicates the logistics of granulocyte collection, banking, and safety testing. Cryopreservation has the potential to significantly increase shelf life; however, cryopreservation of granulocytes has proven to be difficult. In this study, we investigate the membrane permeability properties of human granulocytes, with the ultimate goal of using membrane transport modeling to facilitate development of improved cryopreservation methods. We first measured the equilibrium volume of human granulocytes in a range of hypo- and hypertonic solutions and fit the resulting data using a Boyle-van't Hoff model. This yielded an isotonic cell volume of 378 μm(3) and an osmotically inactive volume of 165 μm(3). To determine the permeability of the granulocyte membrane to water and cryoprotectant (CPA), cells were injected into well-mixed CPA solution while collecting volume measurements using a Coulter Counter. These experiments were performed at temperatures ranging from 4 to 37°C for exposure to dimethyl sulfoxide, glycerol, ethylene glycol, and propylene glycol. The best-fit water permeability was similar in the presence of all of the CPAs, with an average value at 21°C of 0.18 μmatm(-1)min(-1). The activation energy for water transport ranged from 41 to 61 kJ/mol. The CPA permeability at 21°C was 6.4, 1.0, 8.4, and 4.0 μm/min for dimethyl sulfoxide, glycerol, ethylene glycol, and propylene glycol, respectively, and the activation energy for CPA transport ranged between 59 and 68 kJ/mol. Copyright © 2013 Elsevier Inc. All rights reserved.

The comparison of in vivo antigenotoxic and antioxidative capacity of two propylene glycol extracts of Calendula officinalis (marigold) and vitamin E in young growing pigs.

PubMed

Frankic, T; Salobir, K; Salobir, J

2009-12-01

The objective of the study was to evaluate the protective effect of Calendula officinalis propylene glycol extracts against oxidative DNA damage and lipid peroxidation induced by high polyunsaturated fatty acid (PUFA) intake in young growing pigs. Forty young growing pigs were assigned to five treatment groups: control; oil (linseed oil supplementation); C. officinalis 1 and 2 groups (linseed oil plus 3 ml/day of C. officinalis propylene glycol extracts); and vitamin E group (linseed oil plus 100 mg/kg of vitamin E). Lymphocyte DNA fragmentation and 24-h urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) excretion were measured to determine DNA damage. Lipid peroxidation was studied by analysing plasma and urine malondialdehyde (MDA), and urine isoprostane concentrations (iPF2α-VI), total antioxidant status of plasma and glutathione peroxidase (GPx) assays. C. officinalis 1 (extract from petals) effectively protected DNA from oxidative damage. It indicated a numerical trend towards the reduction of plasma MDA and urinary iPF2α-VI excretion. Its effect was comparable with that of vitamin E. C. officinalis 2 (extract from flower tops) showed less antioxidant potential than the extract from petals. We can conclude that the amount of C. officinalis extracts proposed for internal use by traditional medicine protects the organism against DNA damage induced by high PUFA intake.

Metabolism of 2-chloro-1,1-difluoroethene to glyoxylic and glycolic acid in rat hepatic microsomes.

PubMed

Baker, M T; Vasquez, M T; Bates, J N; Chiang, C K

1990-01-01

The complete metabolic fate of the volatile anesthetic halothane is unclear since 2-chloro-1,1-diflurorethene (CDE), a reductive halothane metabolite, is known to readily release inorganic fluoride upon oxidation by cytochrome P-450. This study sought to clarify the metabolism of CDE by determining its metabolites and the roles of induce cytochrome P-450 forms in its metabolism. Upon incubation of [14C]CDE with rat hepatic microsomes, two major radioactive products were found which accounted for greater than 94% of the total metabolites. These compounds were determined to be the nonhalogenated compounds, glyoxylic and glycolic acids, which were formed in a ratio of approximately 1 to 2 of glyoxylic to glycolic acid. No other radioactive metabolites could be detected. Following incubation of CDE with hepatic microsomes isolated from rats treated with cytochrome P-450 inducers, measurement of fluoride release showed that phenobarbital induced CDE metabolism to the greatest degree at high CDE levels, isoniazid was the most effective inducer at low CDE concentrations, and beta-naphthoflavone was ineffective as an inducer. These results suggest that CDE biotransformation primarily involves the generation of an epoxide intermediate, which undergoes mechanisms of decay leading to total dehalogenation of the molecule, and that this metabolism is preferentially carried out by the phenobarbital- and ethanol-inducible forms of cytochrome P-450.

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.

Composition and hydrophilicity control of Mn-doped ferrite (MnxFe3-xO4) nanoparticles induced by polyol differentiation.

PubMed

Vamvakidis, Kosmas; Katsikini, Maria; Vourlias, George; Angelakeris, Mavroeidis; Paloura, Eleni C; Dendrinou-Samara, Catherine

2015-03-28

Manganese doped ferrite (MnxFe3-xO4) nanoparticles with x = 0.29-0.77 were prepared under solvothermal conditions in the presence solely of a polyol using the trivalent manganese and iron acetylacetonates as precursors. In this facile approach, a variety of polyols such as polyethylene glycol (PEG 8000), tetraethylene glycol (TEG), propylene glycol (PG) and a mixture of TEG and PG (1 : 1) were utilized in a triple role as a solvent, a reducing agent and a surface-functionalizing agent. The composition of the fine cubic-spinel structures was found to be related to the reductive ability of each polyol, while determination of structural characteristics plus the inversion parameter (i = 0.18-0.38) were provided by X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy at both the Fe and Mn K-edges. The saturation magnetization increased up to 80 emu g(-1) when x = 0.35 and i = 0.22. In addition, the as-prepared nanocrystals coated with PEG, PG and PG&TEG showed excellent colloidal stability in water, while the TEG-coated particles were not water dispersible and converted to hydrophilic when were extra PEGylated. Measurements of the (1)H NMR relaxation in water were carried out and the nanoprobes were evaluated as potential contrast agents.

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.

In vivo proton MRS to quantify anesthetic effects of pentobarbital on cerebral metabolism and brain activity in rat.

PubMed

Du, Fei; Zhang, Yi; Iltis, Isabelle; Marjanska, Malgorzata; Zhu, Xiao-Hong; Henry, Pierre-Gilles; Chen, Wei

2009-12-01

To quantitatively investigate the effects of pentobarbital anesthesia on brain activity, brain metabolite concentrations and cerebral metabolic rate of glucose, in vivo proton MR spectra, and electroencephalography were measured in the rat brain with various doses of pentobarbital. The results show that (1) the resonances attributed to propylene glycol, a solvent in pentobarbital injection solution, can be robustly detected and quantified in the brain; (2) the concentration of most brain metabolites remained constant under the isoelectric state (silent electroencephalography) with a high dose of pentobarbital compared to mild isoflurane anesthesia condition, except for a reduction of 61% in the brain glucose level, which was associated with a 37% decrease in cerebral metabolic rate of glucose, suggesting a significant amount of "housekeeping" energy for maintaining brain cellular integrity under the isoelectric state; and (3) electroencephalography and cerebral metabolic activities were tightly coupled to the pentobarbital anesthesia depth and they can be indirectly quantified by the propylene glycol resonance signal at 1.13 ppm. This study indicates that in vivo proton MR spectroscopy can be used to measure changes in cerebral metabolite concentrations and cerebral metabolic rate of glucose under varied pentobarbital anesthesia states; moreover, the propylene glycol signal provides a sensitive biomarker for quantitatively monitoring these changes and anesthesia depth noninvasively. (c) 2009 Wiley-Liss, Inc.

Open-label evaluation of a novel skin brightening system containing 0.01% decapeptide-12 in combination with 20% buffered glycolic acid for the treatment of mild to moderate facial melasma.

PubMed

Ramírez, Sandra P; Carvajal, Alfonso C; Salazar, Juan C; Arroyave, Gladys; Flórez, Ana M; Echeverry, Hector F

2013-06-01

Melasma is a cutaneous disorder that primarily affects females of Hispanic and Asian descent. Previous studies have shown that use of a brightening system comprised of 0.01% decapeptide-12 cream, an antioxidant cleanser, a 20% buffered glycolic acid lotion, and a broad spectrum SPF 30 sunscreen yields good clearance of mild-to-moderate melasma in Caucasian and Asian volunteers. The present open-label, prospective, and multicenter study sought to determine the tolerability and efficacy of the above-mentioned brightening system on mild-to-moderate melasma in 33 Hispanic females over 16 weeks. Clinical measures included self-assessment of tolerability, clinical grading, determination of Melasma Area and Severity Index (MASI) scores, and standardized clinical photography. Results showed that the system was well tolerated with no adverse events reported. Mean decreases of 36%, 46%, 54%, and 60% in MASI scores were observed at weeks 4, 8, 12, and 16, respectively, which were further corroborated by standardized photography showing visible reduction in the appearance of melasma. Results suggest that the brightening system consisting of 0.01% decapeptide-12 cream, an antioxidant cleanser, 20% buffered glycolic acid lotion, and broad spectrum SPF 30 sunscreen is safe and efficacious for the treatment of mild-to-moderate melasma in Hispanic females.

Superparamagnetic iron oxide nanoparticles with variable size and an iron oxidation state as prospective imaging agents.

PubMed

Kucheryavy, Pavel; He, Jibao; John, Vijay T; Maharjan, Pawan; Spinu, Leonard; Goloverda, Galina Z; Kolesnichenko, Vladimir L

2013-01-15

Magnetite nanoparticles in the size range of 3.2-7.5 nm were synthesized in high yields under variable reaction conditions using high-temperature hydrolysis of the precursor iron(II) and iron(III) alkoxides in diethylene glycol solution. The average sizes of the particles were adjusted by changing the reaction temperature and time and by using a sequential growth technique. To obtain γ-iron(III) oxide particles in the same range of sizes, magnetite particles were oxidized with dry oxygen in diethylene glycol at room temperature. The products were characterized by DLS, TEM, X-ray powder diffractometry, TGA, chemical analysis, and magnetic measurements. NMR r(1) and r(2) relaxivity measurements in water and diethylene glycol (for OH and CH(2) protons) have shown a decrease in the r(2)/r(1) ratio with the particle size reduction, which correlates with the results of magnetic measurements on magnetite nanoparticles. Saturation magnetization of the oxidized particles was found to be 20% lower than that for Fe(3)O(4) with the same particle size, but their r(1) relaxivities are similar. Because the oxidation of magnetite is spontaneous under ambient conditions, it was important to learn that the oxidation product has no disadvantages as compared to its precursor and therefore may be a better prospective imaging agent because of its chemical stability.

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.

Fine tuning of magnetite nanoparticle size distribution using dissymmetric potential pulses in the presence of biocompatible surfactants and the electrochemical characterization of the nanoparticles.

PubMed

Rodríguez-López, A; Cruz-Rivera, J J; Elías-Alfaro, C G; Betancourt, I; Ruiz-Silva, H; Antaño-López, R

2015-01-01

The effects of varying the surfactant concentration and the anodic pulse potential on the properties and electrochemical behaviors of magnetite nanoparticles were investigated. The nanoparticles were synthesized with an electrochemical method based on applying dissymmetric potential pulses, which offers the advantage that can be used to tune the particle size distribution very precisely in the range of 10 to 50 nm. Under the conditions studied, the surfactant concentration directly affects the size distribution, with higher concentrations producing narrower distributions. Linear voltammetry was used to characterize the electrochemical behavior of the synthesized nanoparticles in both the anodic and cathodic regions, which are attributed to the oxidation of Fe(2+) and the reduction of Fe(3+); these species are part of the spinel structure of magnetite. Electrochemical impedance spectroscopy data indicated that the reduction and oxidation reactions of the nanoparticles are not controlled by the mass transport step, but by the charge transfer step. The sample with the highest saturation magnetization was that synthesized in the presence of polyethylene glycol. Copyright © 2014 Elsevier B.V. All rights reserved.

Concept for Recycling Waste Biomass from the Sugar Industry for Chemical and Biotechnological Purposes.

PubMed

Modelska, Magdalena; Berlowska, Joanna; Kregiel, Dorota; Cieciura, Weronika; Antolak, Hubert; Tomaszewska, Jolanta; Binczarski, Michał; Szubiakiewicz, Elzbieta; Witonska, Izabela A

2017-09-13

The objective of this study was to develop a method for the thermally-assisted acidic hydrolysis of waste biomass from the sugar industry (sugar beet pulp and leaves) for chemical and biotechnological purposes. The distillates, containing furfural, can be catalytically reduced directly into furfurayl alcohol or tetrahydrofurfuryl alcohol. The sugars present in the hydrolysates can be converted by lactic bacteria into lactic acid, which, by catalytic reduction, leads to propylene glycol. The sugars may also be utilized by microorganisms in the process of cell proliferation, and the biomass obtained used as a protein supplement in animal feed. Our study also considered the effects of the mode and length of preservation (fresh, ensilage, and drying) on the yields of furfural and monosaccharides. The yield of furfural in the distillates was measured using gas chromatography with flame ionization detector (GC-FID). The content of monosaccharides in the hydrolysates was measured spectrophotometrically using enzymatic kits. Biomass preserved under all tested conditions produced high yields of furfural, comparable to those for fresh material. Long-term storage of ensiled waste biomass did not result in loss of furfural productivity. However, there were significant reductions in the amounts of monosaccharides in the hydrolysates.

40 CFR 63.1270 - Applicability and designation of affected source.

Code of Federal Regulations, 2013 CFR

2013-07-01

... value. For estimating maximum potential emissions from glycol dehydration units, the glycol circulation... existing glycol dehydration unit specified in paragraphs (b)(1) through (3) of this section. (1) Each large glycol dehydration unit; (2) Each small glycol dehydration unit for which construction commenced on or...

40 CFR 63.1270 - Applicability and designation of affected source.

Code of Federal Regulations, 2014 CFR

2014-07-01

... value. For estimating maximum potential emissions from glycol dehydration units, the glycol circulation... existing glycol dehydration unit specified in paragraphs (b)(1) through (3) of this section. (1) Each large glycol dehydration unit; (2) Each small glycol dehydration unit for which construction commenced on or...

40 CFR 63.760 - Applicability and designation of affected source.

Code of Federal Regulations, 2014 CFR

2014-07-01

... estimating maximum potential emissions from glycol dehydration units, the glycol circulation rate used in the...) Each glycol dehydration unit as specified in paragraphs (b)(1)(i)(A) through (C) of this section. (A) Each large glycol dehydration unit; (B) Each small glycol dehydration unit for which construction...

40 CFR 63.760 - Applicability and designation of affected source.

Code of Federal Regulations, 2013 CFR

2013-07-01

... estimating maximum potential emissions from glycol dehydration units, the glycol circulation rate used in the...) Each glycol dehydration unit as specified in paragraphs (b)(1)(i)(A) through (C) of this section. (A) Each large glycol dehydration unit; (B) Each small glycol dehydration unit for which construction...

21 CFR 172.858 - Propylene glycol alginate.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Propylene glycol alginate. 172.858 Section 172.858... CONSUMPTION Multipurpose Additives § 172.858 Propylene glycol alginate. The food additive propylene glycol... information required by the act: (1) The name of the additive, “propylene glycol alginate” or “propylene...

21 CFR 172.858 - Propylene glycol alginate.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Propylene glycol alginate. 172.858 Section 172.858... CONSUMPTION Multipurpose Additives § 172.858 Propylene glycol alginate. The food additive propylene glycol... information required by the act: (1) The name of the additive, “propylene glycol alginate” or “propylene...

40 CFR Table 1 to Subpart F of... - Synthetic Organic Chemical Manufacturing Industry Chemicals

Code of Federal Regulations, 2010 CFR

2010-07-01

... III Ethylcellulose 9004573 V Ethylcyanoacetate 105566 V Ethylene carbonate 96491 I Ethylene dibromide (Dibromoethane) 106934 I Ethylene glycol 107211 I Ethylene glycol diacetate 111557 I Ethylene glycol dibutyl ether 112481 V Ethylene glycol diethyl ether 629141 I (1,2-diethoxyethane). Ethylene glycol 110714 I...

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...

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...

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...

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...

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...

Material Compatibility Evaluation for DWPF Nitric-Glycolic Acid - Literature Review

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

Mickalonis, J. I.; Skidmore, T. E.

Glycolic acid is being evaluated as an alternative for formic and nitric acid in the DWPF flowsheet. Demonstration testing and modeling for this new flowsheet has shown that glycolic acid and glycolate has a potential to remain in certain streams generated during the production of the nuclear waste glass. A literature review was conducted to assess the impact of glycolic acid on the corrosion of the materials of construction for the DWPF facility as well as facilities downstream which may have residual glycolic acid and glycolates present. The literature data was limited to solutions containing principally glycolic acid. The reportedmore » corrosion rates and degradation characteristics have shown the following for the materials of construction.« less

Propylene glycol intoxication in a dog.

PubMed

Claus, Melissa A; Jandrey, Karl E; Poppenga, Robert H

2011-12-01

To describe the clinical course, treatment, and outcome of a dog with propylene glycol intoxication. An adult castrated male Australian cattle dog presented to an emergency clinic for an acute onset of ataxia and disorientation after roaming a construction site unsupervised. He tested positive for ethylene glycol using a point-of-care test kit. Treatment for ethylene glycol intoxication included intermittent intravenous boluses of 20% ethanol and hemodialysis. Predialysis and postdialysis blood samples were submitted to the toxicology lab to assess for both ethylene and propylene glycol. The patient tested negative for ethylene glycol and positive for propylene glycol at 1100 mg/dL predialysis and 23 mg/dL postdialysis. The dog made a full recovery. To the authors' knowledge, this is the first report of documented propylene glycol intoxication in a dog, as well as the first report to describe hemodialysis as treatment for propylene glycol intoxication in a dog. © Veterinary Emergency and Critical Care Society 2011.

Simulated Waste Testing Of Glycolate Impacts On The 2H-Evaporator System

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

Martino, C. J.

2013-08-13

Glycolic acid is being studied as a total or partial replacement for formic acid in the Defense Waste Processing Facility (DWPF) feed preparation process. After implementation, the recycle stream from DWPF back to the high-level waste tank farm will contain soluble sodium glycolate. Most of the potential impacts of glycolate in the tank farm were addressed via a literature review, but several outstanding issues remained. This report documents the non-radioactive simulant tests impacts of glycolate on storage and evaporation of Savannah River Site high-level waste. The testing for which non-radioactive simulants could be used involved the following: the partitioning ofmore » glycolate into the evaporator condensate, the impacts of glycolate on metal solubility, and the impacts of glycolate on the formation and dissolution of sodium aluminosilicate scale within the evaporator. The following are among the conclusions from this work: Evaporator condensate did not contain appreciable amounts of glycolate anion. Of all tests, the highest glycolate concentration in the evaporator condensate was 0.38 mg/L. A significant portion of the tests had glycolate concentration in the condensate at less than the limit of quantification (0.1 mg/L). At ambient conditions, evaporator testing did not show significant effects of glycolate on the soluble components in the evaporator concentrates. Testing with sodalite solids and silicon containing solutions did not show significant effects of glycolate on sodium aluminosilicate formation or dissolution.« less

Development of Novel Technetium-99m-Labeled Steroids as Estrogen-Responsive Breast Cancer Imaging Agents

DTIC Science & Technology

2007-06-01

alkylation with α,ω-ditosyloxy triethylene glycol, followed by displacement with sodium azide, aromatization and reduction of the 17- keto group give the...17alpha.-E- (trifluoromethylphenyl)vinyl estradiols as novel estrogen receptor ligands. Steroids 2003, 68, 143 -148. 23. Hanson, R.N., Dilis, R...R. N.; Lee, C. Y.; Friel, C.; Hughes, A.; DeSombre, E. R. Steroids 2003, 68, 143 -148. (c) Hanson, R. N.; Tongcharoensirikul, P.; Dilis, R.; Hughes

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.

Removal of fumonisin B1 and B2 from model solutions and red wine using polymeric substances.

PubMed

Carrasco-Sánchez, Verónica; Kreitman, Gal Y; Folch-Cano, Christian; Elias, Ryan J; Laurie, V Felipe

2017-06-01

Fumonisins are a group of mycotoxins found in various foods whose consumption is known to be harmful for human health. In this study, we evaluated the ability of three polymers (Polyvinylpolypyrrolidone, PVPP; a resin of N-vinyl-2-pyrrolidinone with ethylene glycol dimethacrylate and triallyl isocyanurate, PVP-DEGMA-TAIC; and poly(acrylamide-co-ethylene glycol-dimethacrylate), PA-EGDMA) to remove fumonisin B 1 (FB1) and fumonisin B 2 (FB2) from model solutions and red wine. Various polymer concentrations (1, 5 and 10mgmL -1 ) and contact times (2, 8 and 24h) were tested, with all polymers exhibiting fumonisin removal capacities (monitored by LC-MS). The impact of all polymers on polyphenol removal was also assessed. PA-EGDMA showed to be the most promising polymer, removing 71% and 95% of FB 1 , and FB 2 , respectively, with only a 22.2% reduction in total phenolics. Copyright © 2016 Elsevier Ltd. All rights reserved.

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.

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.

3D printing of new biobased unsaturated polyesters by microstereo-thermallithography.

PubMed

Gonçalves, Filipa A M M; Costa, Cátia S M F; Fabela, Inês G P; Farinha, Dina; Faneca, Henrique; Simões, Pedro N; Serra, Arménio C; Bártolo, Paulo J; Coelho, Jorge F J

2014-09-01

New micro three-dimensional (3D) scaffolds using biobased unsaturated polyesters (UPs) were prepared by microstereo-thermal-lithography (μSTLG). This advanced processing technique offers indubitable advantages over traditional printing methods. The accuracy and roughness of the 3D structures were evaluated by scanning electron microscopy and infinite focus microscopy, revealing a suitable roughness for cell attachment. UPs were synthesized by bulk polycondensation between biobased aliphatic diacids (succinic, adipic and sebacic acid) and two different glycols (propylene glycol and diethylene glycol) using fumaric acid as the source of double bonds. The chemical structures of the new oligomers were confirmed by proton nuclear magnetic resonance spectra, attenuated total reflectance Fourier transform infrared spectroscopy and matrix assisted laser desorption/ionization-time of flight mass spectrometry. The thermal and mechanical properties of the UPs were evaluated to determine the influence of the diacid/glycol ratio and the type of diacid in the polyester's properties. In addition an extensive thermal characterization of the polyesters is reported. The data presented in this work opens the possibility for the use of biobased polyesters in additive manufacturing technologies as a route to prepare biodegradable tailor made scaffolds that have potential applications in a tissue engineering area.

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

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.

Kinetic and thermodynamic studies of AISI 4130 steel alloy corrosion in ethylene glycol-water mixture in presence of inhibitors

NASA Astrophysics Data System (ADS)

Khomami, M. Niknejad; Danaee, I.; Attar, A. A.; Peykari, M.

2013-05-01

The electrochemical behavior of steel alloy in ethylene glycol-water mixture was investigated by electrochemical methods. The results obtained showed that corrosion rate was decreased with increasing ethylene glycol concentration. The effect of inorganic inhibitors including NO3 -, NO2 -, Cr2O7 2- and CrO4 2- were studied using electrochemical techniques where the highest inhibition efficiency was obtained for CrO4 2-. In the presence of chromate the inhibitor efficiency increased with its concentration. The inhibiting effect of the chromate was explained on the basis of the competitive adsorption between the inorganic anions and the aggressive Cl- ions, and the adsorption isotherm basically obeys the Langmuir adsorption isotherm. Thermodynamic parameters for steel corrosion and inhibitor adsorption were determined and reveal that the adsorption process is spontaneous. Also, a phenomenon of both physical and chemical adsorption is proposed.

Characterization of Tin/Ethylene Glycol Solar Nanofluids Synthesized by Femtosecond Laser Radiation.

PubMed

Torres-Mendieta, Rafael; Mondragón, Rosa; Puerto-Belda, Verónica; Mendoza-Yero, Omel; Lancis, Jesús; Juliá, J Enrique; Mínguez-Vega, Gladys

2017-05-05

Solar energy is available over wide geographical areas and its harnessing is becoming an essential tool to satisfy the ever-increasing demand for energy with minimal environmental impact. Solar nanofluids are a novel solar receiver concept for efficient harvesting of solar radiation based on volumetric absorption of directly irradiated nanoparticles in a heat transfer fluid. Herein, the fabrication of a solar nanofluid by pulsed laser ablation in liquids was explored. This study was conducted with the ablation of bulk tin immersed in ethylene glycol with a femtosecond laser. Laser irradiation promotes the formation of tin nanoparticles that are collected in the ethylene glycol as colloids, creating the solar nanofluid. The ability to trap incoming electromagnetic radiation, thermal conductivity, and the stability of the solar nanofluid in comparison with conventional synthesis methods is enhanced. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

Study on cryopreservation of Porphyra yezoensis conchocelis

NASA Astrophysics Data System (ADS)

Zhou, Wenjun; Li, Yun; Dai, Jixun

2007-07-01

Cryopreservation of Porphyra yezoensis conchocelis was conducted with cryoprotectants and a proposed pretreatment procedure and thawing methods explored. Six cryoprotectants combined by DMSO with ethylene glycol (EG), propylene glycol (PEG), sorbitol and sucrose were developed. The effect of prefreezing at -40°C or -20°C for different time durations was compared and the thawing methods were screened. It was shown that the cryoprotectant including 10% DMSO with 0.5 molL-1 sorbitol exhibited the optimal effect. The ideal pretreatment was that conchocelis segments were stayed for 20 min at -40°C before stored in liquid nitrogen, and 40°C water bath was proper for quick thawing. The highest recovery rate of cryopreserved P. yezoensis conchocelis reached 89.41%.

Smart poly(oligo(propylene glycol) methacrylate) hydrogel prepared by gamma radiation

NASA Astrophysics Data System (ADS)

Suljovrujic, E.; Micic, M.

2015-01-01

The synthesis of poly(oligo(propylene glycol) methacrylate) (POPGMA) from functionalised oligo(propylene glycol) methacrylate (OPGMA) monomers by gamma radiation-induced radical polymerisation is reported for the first time; POPGMA homopolymeric hydrogel with oligo(propylene glycol) (OPG) pendant chains, as a non-linear PPGMA-analogue, was synthesised from an monomer-solvent (OPGMA375-water/ethanol) mixture at different irradiation doses (5, 10, 25, and 40 kGy). Determination of the gel fraction was conducted after synthesis. The swelling properties of the POPGMA hydrogel were preliminarily investigated over wide pH (2.2-9.0) and temperature (4-70 °C) ranges. Additional characterisation of structure and properties was conducted by UV-vis and Fourier transform infrared (FTIR) spectroscopy as well as by differential scanning calorimetry (DSC). In order to evaluate the potential for biomedical applications, biocompatibility (cytocompatibility and haemolytic activity) studies were performed as well. Sol-gel conversion was relatively high for all irradiation doses, indicating radiation-induced synthesis as a good method for fabricating this hydrogel. Thermoresponsiveness and variations in swelling capacity as a result of thermosensitive OPG pendant chains with a lower critical solution temperature (LCST) were mainly observed below room temperature; thus, the volume phase transition temperature (VPTT) of POPGMA homopolymeric hydrogel is about 15 °C. Furthermore, POPGMA has satisfactory biocompatibility. The results indicate that the hydrogels with propylene glycol pendant chains can be easily prepared by gamma radiation and have potential for different applications as smart and biocompatible polymers.

40 CFR 180.1250 - C8, C10, and C12 fatty acid monoesters of glycerol and propylene glycol; exemption from the...

Code of Federal Regulations, 2012 CFR

2012-07-01

... of glycerol and propylene glycol; exemption from the requirement of a tolerance. 180.1250 Section 180..., C10, and C12 fatty acid monoesters of glycerol and propylene glycol; exemption from the requirement of... monocaprylate, glycerol monocaprate, and glycerol monolaurate) and propylene glycol (propylene glycol...

40 CFR 180.1250 - C8, C10, and C12 fatty acid monoesters of glycerol and propylene glycol; exemption from the...

Code of Federal Regulations, 2013 CFR

2013-07-01

... of glycerol and propylene glycol; exemption from the requirement of a tolerance. 180.1250 Section 180..., C10, and C12 fatty acid monoesters of glycerol and propylene glycol; exemption from the requirement of... monocaprylate, glycerol monocaprate, and glycerol monolaurate) and propylene glycol (propylene glycol...

40 CFR 180.1250 - C8, C10, and C12 fatty acid monoesters of glycerol and propylene glycol; exemption from the...

Code of Federal Regulations, 2014 CFR

2014-07-01

... of glycerol and propylene glycol; exemption from the requirement of a tolerance. 180.1250 Section 180..., C10, and C12 fatty acid monoesters of glycerol and propylene glycol; exemption from the requirement of... monocaprylate, glycerol monocaprate, and glycerol monolaurate) and propylene glycol (propylene glycol...

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.

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

Ethylene glycol blood test

MedlinePlus

... this page: //medlineplus.gov/ency/article/003564.htm Ethylene glycol blood test To use the sharing features ... enable JavaScript. This test measures the level of ethylene glycol in the blood. Ethylene glycol is a ...

Common hydraulic fracturing fluid additives alter the structure and function of anaerobic microbial communities

USGS Publications Warehouse

Mumford, Adam C.; Akob, Denise M.; Klinges, J. Grace; Cozzarelli, Isabelle M.

2018-01-01

The development of unconventional oil and gas (UOG) resources results in the production of large volumes of wastewater containing a complex mixture of hydraulic fracturing chemical additives and components from the formation. The release of these wastewaters into the environment poses potential risks that are poorly understood. Microbial communities in stream sediments form the base of the food chain and may serve as sentinels for changes in stream health. Iron-reducing organisms have been shown to play a role in the biodegradation of a wide range of organic compounds, and so to evaluate their response to UOG wastewater, we enriched anaerobic microbial communities from sediments collected upstream (background) and downstream (impacted) of an UOG wastewater injection disposal facility in the presence of hydraulic fracturing fluid (HFF) additives: guar gum, ethylene glycol, and two biocides, 2,2-dibromo-3-nitrilopropionamide (DBNPA) and bronopol (C3H6BrNO4). Iron reduction was significantly inhibited early in the incubations with the addition of biocides, whereas amendment with guar gum and ethylene glycol stimulated iron reduction relative to levels in the unamended controls. Changes in the microbial community structure were observed across all treatments, indicating the potential for even small amounts of UOG wastewater components to influence natural microbial processes. The microbial community structure differed between enrichments with background and impacted sediments, suggesting that impacted sediments may have been preconditioned by exposure to wastewater. These experiments demonstrated the potential for biocides to significantly decrease iron reduction rates immediately following a spill and demonstrated how microbial communities previously exposed to UOG wastewater may be more resilient to additional spills.

Microemulsification: an approach for analytical determinations.

PubMed

Lima, Renato S; Shiroma, Leandro Y; Teixeira, Alvaro V N C; de Toledo, José R; do Couto, Bruno C; de Carvalho, Rogério M; Carrilho, Emanuel; Kubota, Lauro T; Gobbi, Angelo L

2014-09-16

We address a novel method for analytical determinations that combines simplicity, rapidity, low consumption of chemicals, and portability with high analytical performance taking into account parameters such as precision, linearity, robustness, and accuracy. This approach relies on the effect of the analyte content over the Gibbs free energy of dispersions, affecting the thermodynamic stabilization of emulsions or Winsor systems to form microemulsions (MEs). Such phenomenon was expressed by the minimum volume fraction of amphiphile required to form microemulsion (Φ(ME)), which was the analytical signal of the method. Thus, the measurements can be taken by visually monitoring the transition of the dispersions from cloudy to transparent during the microemulsification, like a titration. It bypasses the employment of electric energy. The performed studies were: phase behavior, droplet dimension by dynamic light scattering, analytical curve, and robustness tests. The reliability of the method was evaluated by determining water in ethanol fuels and monoethylene glycol in complex samples of liquefied natural gas. The dispersions were composed of water-chlorobenzene (water analysis) and water-oleic acid (monoethylene glycol analysis) with ethanol as the hydrotrope phase. The mean hydrodynamic diameter values for the nanostructures in the droplet-based water-chlorobenzene MEs were in the range of 1 to 11 nm. The procedures of microemulsification were conducted by adding ethanol to water-oleic acid (W-O) mixtures with the aid of micropipette and shaking. The Φ(ME) measurements were performed in a thermostatic water bath at 23 °C by direct observation that is based on the visual analyses of the media. The experiments to determine water demonstrated that the analytical performance depends on the composition of ME. It shows flexibility in the developed method. The linear range was fairly broad with limits of linearity up to 70.00% water in ethanol. For monoethylene glycol in water, in turn, the linear range was observed throughout the volume fraction of analyte. The best limits of detection were 0.32% v/v water to ethanol and 0.30% v/v monoethylene glycol to water. Furthermore, the accuracy was highly satisfactory. The natural gas samples provided by the Petrobras exhibited color, particulate material, high ionic strength, and diverse compounds as metals, carboxylic acids, and anions. These samples had a conductivity of up to 2630 μS cm(-1); the conductivity of pure monoethylene glycol was only 0.30 μS cm(-1). Despite such downsides, the method allowed accurate measures bypassing steps such as extraction, preconcentration, and dilution of the sample. In addition, the levels of robustness were promising. This parameter was evaluated by investigating the effect of (i) deviations in volumetric preparation of the dispersions and (ii) changes in temperature over the analyte contents recorded by the method.

Safety assessment of propylene glycol, tripropylene glycol, and PPGs as used in cosmetics.

PubMed

Fiume, Monice M; Bergfeld, Wilma F; Belsito, Donald V; Hill, Ronald A; Klaassen, Curtis D; Liebler, Daniel; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Andersen, F Alan

2012-01-01

Propylene glycol is an aliphatic alcohol that functions as a skin conditioning agent, viscosity decreasing agent, solvent, and fragrance ingredient in cosmetics. Tripropylene glycol functions as a humectant, antioxidant, and emulsion stabilizer. Polypropylene glycols (PPGs), including PPG-3, PPG-7, PPG-9, PPG-12, PPG-13, PPG-15, PPG-16, PPG-17, PPG-20, PPG-26, PPG-30, PPG-33, PPG-34, PPG-51, PPG-52, and PPG-69, function primarily as skin conditioning agents, with some solvent use. The majority of the safety and toxicity information presented is for propylene glycol (PG). Propylene glycol is generally nontoxic and is noncarcinogenic. Clinical studies demonstrated an absence of dermal sensitization at use concentrations, although concerns about irritation remained. The CIR Expert Panel determined that the available information support the safety of tripropylene glycol as well as all the PPGs. The Expert Panel concluded that PG, tripropylene glycol, and PPGs ≥3 are safe as used in cosmetic formulations when formulated to be nonirritating.

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.

Investigation of selected potential environmental contaminants: ethylene glycol, propylene glycols and butylene glycols. Final report

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

Miller, L.M.

1979-05-01

This report reviews aspects of production, use, environmental exposure and biological effects of ethylene glycol, two isomers of propylene glycol (1,2- and 1,3-propanediol) and four isomers of butylene glycol (1,3-, 1,4-, 2,3-, and 1,2- butanediol). Annual production of ethylene glycol is about 3.7 billion pounds for use primarily in antifreeze and polyester fiber. About 0.5 billion pounds of 1,2-propanediol are produced per year for use in polyester resins, food, pharmaceuticals, and cellophane. Annual domestic demand for 1,4-butanediol is about 0.2 billion pounds for use in the production of tetra-hydrofuran and acetylenic chemicals. The other title glycols are of less importancemore » commercially. The major source of environmental contamination by ethylene glycol and 1,2-propanediol is likely from the disposal of spent antifreeze and de-icing fluids. However, limited monitoring data make it difficult to adequately assess environmental exposure to the glycols. The glycols are capable of being degraded by a variety of acclimated and unacclimated soil, water, and sewage microorganisms. In humans, ethylene glycol intoxication, usually as a result of accidental ingestion of antifreeze, may result in nausea, hypertension, tachycardia, cardiopulmonary failure, renal impairment, coma and death. 1,2-Propanediol is a GRAS food additive of low toxicity. 1,3-Butanediol has been studied as a source of dietary energy. Few studies are available on 1,2-, 2,3- and 1,4-butanediol or on 1,3-propanediol.« less

A strong adjuvant based on glycol-chitosan-coated lipid-polymer hybrid nanoparticles potentiates mucosal immune responses against the recombinant Chlamydia trachomatis fusion antigen CTH522.

PubMed

Rose, Fabrice; Wern, Jeanette Erbo; Gavins, Francesca; Andersen, Peter; Follmann, Frank; Foged, Camilla

2018-02-10

Induction of mucosal immunity with vaccines is attractive for the immunological protection against pathogen entry directly at the site of infection. An example is infection with Chlamydia trachomatis (Ct), which is the most common sexually transmitted infection in the world, and there is an unmet medical need for an effective vaccine. A vaccine against Ct should elicit protective humoral and cell-mediated immune (CMI) responses in the genital tract mucosa. We previously designed an antibody- and CMI-inducing adjuvant based on poly(dl-lactic-co-glycolic acid) (PLGA) nanoparticles modified with the cationic surfactant dimethyldioctadecylammonium bromide and the immunopotentiator trehalose-6,6'-dibehenate. Here we show that immunization with these lipid-polymer hybrid nanoparticles (LPNs) coated with the mucoadhesive polymer chitosan enhances mucosal immune responses. Glycol chitosan (GC)-modified LPNs were engineered using an oil-in-water single emulsion solvent evaporation method. The nanoparticle design was optimized in a highly systematic way by using a quality-by-design approach to define the optimal operating space and to gain maximal mechanistic information about the GC coating of the LPNs. Cryo-transmission electron microscopy revealed a PLGA core coated with one or several concentric lipid bilayers. The GC coating of the surface was identified as a saturable, GC concentration-dependent increase in particle size and a reduction of the zeta-potential, and the coating layer could be compressed upon addition of salt. Increased antigen-specific mucosal immune responses were induced in the lungs and the genital tract with the optimized GC-coated LPN adjuvant upon nasal immunization of mice with the recombinant Ct fusion antigen CTH522. The mucosal responses were characterized by CTH522-specific IgG/IgA antibodies, together with CTH522-specific interferon γ-producing Th1 cells. This study demonstrates that mucosal administration of CTH522 adjuvanted with chitosan-coated LPNs represents a promising strategy to modulate the magnitude of mucosal vaccine responses. Copyright © 2017 Elsevier B.V. All rights reserved.

Plasticization of poly(lactic acid) using different molecular weight of Poly(ethylene glycol)

NASA Astrophysics Data System (ADS)

Septevani, Athanasia Amanda; Bhakri, Samsul

2017-11-01

Poly (lactic acid) (PLA) has been known as an excellent candidate for developing the future bioplastic due to its biodegradability and competitive price. However, inherent brittleness and low thermal stability of PLA have limited its applications. Considerable studies have been developed to improve the flexibility of PLA, in which blending PLA with various plasticizers has been identified as a cost-effective way to lower glass-transition temperature (Tg) and thus improve its elongation property. In this study, PLA was modified by incorporating poly(ethylene glycol) as a plasticizer with different molecular weights (M¯w 400, 1000, and 6000, called respectively as PEG 400, PEG 1000, and PEG 6000) via a solvent-casting blend method. FTIR was used for analyzing the chemical interaction while TGA and DSC measured the thermal behavior of PLA/PEG. The results indicated that the addition of lower M¯w (PEG 400 and PEG 1000) could reduce the Tg due to the enhancement of chain mobility of PLA with PEG and so driving into a more amorphous states resulted reduction of melting temperature (Tm) compared to the neat PLA. Further, at a higher M¯w of PEG 6000, the longer chain of ethylene glycol, in contrast, resulted a gradual increase in the Tg as well as Tm where the value went back to the point of neat PLA compared to the other lower molecular weight of PLA. This was due to the decrease in polymer miscibility with the increasing of M¯w. In terms of thermal stability, the addition of PEG exhibited two step degradation behavior while the neat PLA only possessed single step degradation. The presence of PEG could act as a protective barrier layer that could hinder the permeability of the volatile compound and product during decomposition reaction and thus could eventually delay and slower the degradation process. It was observed that the addition of PEG at higher M¯w (PEG1000 and PEG 6000) exhibited a higher second degradation temperature up to 380 °C.

Effect of the nanostructure and the surface composition of bimetallic Ni-Ru nanoparticles on the performance of CO methanation

NASA Astrophysics Data System (ADS)

Wang, Jing; Yuan, Changkun; Yao, Nan; Li, Xiaonian

2018-05-01

The Ni/SiO2 catalysts with trace Ru promoter were prepared by either polyethylene glycol (PEG)-assisted or PEG-free impregnation method and were used in CO methanation reaction. The presence of PEG molecules was beneficial to form bimetallic Ni-Ru particles with smaller size, better anti-sintering property and low-temperature reducibility on SiO2 support than the conventional PEG-free derived NiRu/SiO2 catalyst. Moreover, it was found that the low-temperature reduction at 573 K was favorable to form bimetallic Ni-Ru particles with more surface Ru atoms. This nanostructure not only allowed the electron transfer happening from Ru0 to Ni0 which led to its higher electron cloud density, but also could reduce the deposition of less reactive carbon on the catalyst. Therefore, the low-temperature reduction enhanced the reaction stability of NiRu/SiO2 catalyst. The increase of reduction temperature from 573 K to 693 K did not change the size of metallic particles, but decreased the amount of surface Ru atoms. It deactivated the catalyst due to the deposition of more less reactive carbon. Although the higher reduction temperature (e.g. 693 and 793 K) was unfavorable to the reaction stability, it created more surface defects. The amount of defects showed a volcano-shaped correlation with the reduction temperature which was consistent with the variation tendency of turnover frequency of CO conversion. Consequently, it evidenced that the amount of surface Ru atoms and defects on the bimetallic Ni-Ru particle played the critical roles on the stability and the intrinsic activity of methanation, respectively.

Structure elucidation and degradation kinetic study of Ofloxacin using surface enhanced Raman spectroscopy

NASA Astrophysics Data System (ADS)

El-Zahry, Marwa R.; Lendl, Bernhard

2018-03-01

A simple, fast and sensitive surface enhanced Raman spectroscopy (SERS) method for quantitative determination of fluoroquinolone antibiotic Ofloxacin (OFX) is presented. Also the stability behavior of OFX was investigated by monitoring the SERS spectra of OFX after various degradation processes. Acidic, basic and oxidative force degradation processes were applied at different time intervals. The forced degradation conditions were conducted and followed using SERS method utilizing silver nanoparticles (Ag NPs) as a SERS substrate. The Ag NPs colloids were prepared by reduction of silver nitrate using polyethyelene glycol (PEG) as a reducing and stabilizing agent. Validation tests were done in accordance with International Conference on Harmonization (ICH) guidelines. The calibration curve with a correlation coefficient (R = 0.9992) was constructed as a relationship between the concentration range of OFX (100-500 ng/ml) and SERS intensity at 1394 cm- 1 band. LOD and LOQ values were calculated and found to be 23.5 ng/ml and 72.6 ng/ml, respectively. The developed method was applied successfully for quantitation of OFX in different pharmaceutical dosage forms. Kinetic parameters were calculated including rate constant of the degradation of the studied antibiotic.

21 CFR 500.50 - Propylene glycol in or on cat food.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Propylene glycol in or on cat food. 500.50 Section... Propylene glycol in or on cat food. The Food and Drug Administration has determined that propylene glycol in... determined that this use of propylene glycol is not prior sanctioned. [61 FR 19544, May 2, 1996] ...

21 CFR 500.50 - Propylene glycol in or on cat food.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Propylene glycol in or on cat food. 500.50 Section... Propylene glycol in or on cat food. The Food and Drug Administration has determined that propylene glycol in... determined that this use of propylene glycol is not prior sanctioned. [61 FR 19544, May 2, 1996] ...

21 CFR 500.50 - Propylene glycol in or on cat food.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Propylene glycol in or on cat food. 500.50 Section... Propylene glycol in or on cat food. The Food and Drug Administration has determined that propylene glycol in... determined that this use of propylene glycol is not prior sanctioned. [61 FR 19544, May 2, 1996] ...

Influence of propylene glycol on aqueous silica dispersions and particle-stabilized emulsions.

PubMed

Binks, Bernard P; Fletcher, Paul D I; Thompson, Michael A; Elliott, Russell P

2013-05-14

We have studied the influence of adding propylene glycol to both aqueous dispersions of fumed silica nanoparticles and emulsions of paraffin liquid and water stabilized by the same particles. In the absence of oil, aerating mixtures of aqueous propylene glycol and particles yields either stable dispersions, aqueous foams, climbing particle films, or liquid marbles depending on the glycol content and particle hydrophobicity. The presence of glycol in water promotes particles to behave as if they are more hydrophilic. Calculations of their contact angle at the air-aqueous propylene glycol surface are in agreement with these findings. In the presence of oil, particle-stabilized emulsions invert from water-in-oil to oil-in-water upon increasing either the inherent hydrophilicity of the particles or the glycol content in the aqueous phase. Stable multiple emulsions occur around phase inversion in systems of low glycol content, and completely stable, waterless oil-in-propylene glycol emulsions can also be prepared. Accounting for the surface energies at the respective interfaces allows estimation of the contact angle at the oil-polar phase interface; reasonable agreement between measured and calculated phase inversion conditions is found assuming no glycol adsorption on particle surfaces.

An HPLC Method for Microanalysis and Pharmacokinetics of Marine Sulfated Polysaccharide PSS-Loaded Poly Lactic-co-Glycolic Acid (PLGA) Nanoparticles in Rat Plasma

PubMed Central

Li, Peng-Li; Li, Chun-Xia; Xue, Yi-Ting; Li, Hai-Hua; Liu, Hong-Bing; He, Xiao-Xi; Yu, Guang-Li; Guan, Hua-Shi

2013-01-01

This study was aimed at developing a sensitive and selective HPLC method with postcolumn fluorescence derivatization for the detection of propylene glycol alginate sodium sulfate (PSS) in rat plasma. Plasma samples were prepared by a simple and fast ultrafiltration method. PSS was extracted from rat plasma with d-glucuronic acid as internal standard. Isocratic chromatographic separation was performed on a TSKgel G2500 PWxL column with the mobile phase of 0.1 M sodium sulfate at a flow rate of 0.5 mL/min. Analyte detection was achieved by fluorescence detection (FLD) at 250 nm (excitation) and 435 nm (emission) using guanidine hydrochloride as postcolumn derivatizing reagent in an alkaline medium at 120 °C. The calibration curve was linear over a concentration range of 1–500 μg/mL, and the lower limit of detection (LLOD) was found to be 250 ng/mL. This validated method was applied successfully to the pharmacokinetic study of PSS and PSS-loaded poly lactic-co-glycolic acid (PLGA) nanoparticles (PSS-NP) in rat plasma after a single intravenous (PSS only) and oral administration (PSS and PSS-NP). Significant differences in the main pharmacokinetic parameters of PSS and PSS-NP were observed. The relative bioavailability of PSS-NP was 190.10% compared with PSS which shows that PSS-NP can improve oral bioavailability. PMID:23549283

Preparation of ultrafine grained copper nanoparticles via immersion deposit method

NASA Astrophysics Data System (ADS)

Abbasi-Kesbi, Fatemeh; Rashidi, Ali Mohammad; Astinchap, Bandar

2018-03-01

Today, the exploration about synthesis of nanoparticles is much of interest to materials scientists. In this work, copper nanoparticles have been successfully synthesized by immersion deposit method in the absence of any stabilizing and reducing agents. Copper (II) sulfate pentahydrate as precursor salt and distilled water and Ethylene glycol as solvents were used. The copper nanoparticles were deposited on plates of low carbon steel. The effects of copper sulfate concentrations and solvent type were investigated. X-ray diffraction, scanning electron microscopy and UV-Visible spectroscopy were taken to investigate the crystallite size, crystal structure, and morphology and size distribution and the growth process of the nanoparticles of obtained Cu particles. The results indicated that the immersion deposit method is a particularly suitable method for synthesis of semispherical copper nanoparticles with the crystallites size in the range of 22 to 37 nm. By increasing the molar concentration of copper sulfate in distilled water solvent from 0.04 to 0.2 M, the average particles size is increased from 57 to 81 nm. The better size distribution of Cu nanoparticles was achieved using a lower concentration of copper sulfate. By increasing the molar concentration of copper sulfate in water solvent from 0.04 to 0.2, the location of the SPR peak has shifted from 600 to 630 nm. The finer Cu nanoparticles were formed using ethylene glycol instead water as a solvent. Also, the agglomeration and overlapping of nanoparticles in ethylene glycol were less than that of water solvent.

An efficacious oral health care protocol for immunocompromised patients.

PubMed

Solomon, C S; Shaikh, A B; Arendorf, T M

1995-01-01

A twice-weekly oral and perioral examination was provided to 120 patients receiving antineoplastic therapy. Sixty patients were monitored while following the traditional hospital oral care protocol (chlorhexidine, hydrogen peroxide, sodium bicarbonate, thymol glycol, benzocaine mouthrinse, and nystatin). The mouth care protocol was then changed (experimental protocol = chlorhexidine, benzocaine lozenges, amphotericin B lozenges), and patients were monitored until the sample size matched that of the hospital mouth care regime. There was a statistically significant reduction in oral complications upon introduction and maintenance of the experimental protocol.

Ru(II) -mediated hydrogen transfer from aqueous glycerol to CO2: from waste to value-added products.

PubMed

Dibenedetto, Angela; Stufano, Paolo; Nocito, Francesco; Aresta, Michele

2011-09-19

Aqueous glycerol was used as the hydrogen source for the reduction of CO(2) to the hydrogen carrier formic acid in the presence of the catalyst [RuCl(2)(PPh(3))(3)]. All intermediates were identified and characterized. Glycerol was converted into glycolic acid, HO-CH(2)-COOH, that was identified by using (1)H and (13)C NMR spectroscopy. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Catalytic Deoxydehydration of Carbohydrates and Polyols to Chemicals and Fuels

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

Nicholas, Kenneth M.

As the world's fossil fuel resources are being depleted and their costs increase, there is an urgent need to discover and develop new processes for the conversion of renewable, biomass resources into fuels and chemical feedstocks. Research and development in this area have been given high priority by both governmental agencies and industry. To increase the energy content and decrease the boiling points of biomass-derived carbohydrates and polyols to the useful liquid range it is necessary to chemically remove water (dehydrate) and, preferably, oxygen (deoxygenate/reduce). The poly-hydroxylic nature of carbohydrates is attractive for their use as functionalized chemical building blocks,more » but it presents a daunting challenge for their selective conversion to single product chemicals or fuels. The long term, practical objective of this project is to develop catalytic processes for the deoxydehydration (DODH) of biomass-derived carbohydrates and polyols to produce unsaturated alcohols and hydrocarbons of value as chemical feedstocks and fuels; DODH: polyol + reductant --(LMOx catalyst)--> unsaturate + oxidized reductant + H2O. Limited prior studies have established the viability of the DODH process with expensive phosphine reductants and rhenium-catalysts. Initial studies in the PI's laboratory have now demonstrated: 1) the moderately efficient conversion of glycols to olefins by the economical sulfite salts is catalyzed by MeReO3 and Z+ReO4-; 2) effective phosphine-based catalytic DODH of representative glycols to olefins by cheap LMoO2 complexes; and 3) computational studies (with K. Houk, UCLA) have identified several Mo-, W-, and V-oxo complexes that are likely to catalyze glycol DODH. Seeking practically useful DODH reactions of complex polyols and new understanding of the reactivity of polyoxo-metal species with biomass-oxygenates we will employ a two-pronged approach: 1) investigate experimentally the reactivity, both stoichiometric and catalytic, of polyoxo-complexes and practical reductants with representative polyols to establish structure/reactivity relationships and reaction mechanisms; and b) carry out parallel computational studies of these reactions and their mechanisms- both analytical and predictive. Our prioritized action plan is: (1) to optimize the catalytic efficiency, assess the substrate scope/selectivity, and address key mechanistic aspects of Re-catalyzed, sulfite-driven DODH reactions; (2) use the findings from (1), together with computational predictions, to discover new, effective non-precious metal catalysts for sulfite-driven DODH reactions; and 3) to initiate exploratory studies of CO- and H2-driven DODH. Successful execution of this research project will: 1) provide practical chemical processes for the conversion of biomass into useful chemicals and fuels: 2) bring fundamental new understanding of chemical reactions involving metal-oxo catalysts; and 3) provide educational and technical training of future energy scientists.« less

Aphids preserved in propylene glycol can be used for reverse transcription-polymerase chain reaction detection of Potato virus Y.

PubMed

Nie, Xianzhou; Pelletier, Yvan; Mason, Nicola; Dilworth, Andrea; Giguère, Marie-Andrée

2011-08-01

The effectiveness of propylene glycol on the retention of RNA target of Potato virus Y (PVY), an aphid stylet-borne virus, in Myzus persicae was investigated in comparison to ethanol and liquid nitrogen/-80°C. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the PVY targets from the propylene glycol/ethanol/liquid nitrogen preserved single aphids after a 5min acquisition period from infected potato plants. In the liquid nitrogen/-80°C and 70% ethanol treatments, 55.6% and 38.8% aphids tested PVY-positive, respectively. In the 0-75% propylene glycol treatments, 12.2-44.7% aphids tested PVY-positive. The lowest detection rate was in the 0% (positive rate, 15.2%) and the 10% propylene glycol (positive rate, 12.2%). As the propylene glycol concentration increased to 25%, 29.8% aphids tested positive. A high PVY-positive rate was also found in 35-75% propylene glycol treatments at 44.7% (35% propylene glycol), 36.7% (50% propylene glycol) and 34.8% (75% propylene glycol), which is comparable to the rate shown in 70% ethanol. No significant difference in the positive detection rate was observed in aphids preserved in 50% propylene glycol at room temperature for 2, 4 and 10 days. These results demonstrate that propylene glycol at 25-75% can retain PVY targets effectively in aphids for an extended time period, and thus can be used in aphid traps to preserve viruliferous aphids for later RT-PCR detection of PVY. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

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.

A facile solvothermal method to produce graphene-ZnS composites for superior photoelectric applications

NASA Astrophysics Data System (ADS)

Lei, Yun; Chen, Feifei; Li, Rong; Xu, Jun

2014-07-01

In this experiment, flake graphite (<30 μm) was prepared as raw materials. Graphite oxide is prepared with Hummers method by low temperature, middle temperature and high temperature, and further treated with super-sonic oscillation to get graphene oxide. Graphene-zinc sulfide composites were synthesized through a simple solvothermal method using thiourea or sodium sulfide as sulfur source in the ethylene glycol or ethylenediamine, respectively. The products were characterized by X-ray and SEM, and analyzed by the transient photocurrent response and electrochemical impedance spectra. The results indicate that the properties of graphene-zinc sulfide composites prepared with thiourea in ethylene glycol are superior to those of blank-ZnS and composites prepared with sodium sulfide and ethylenediamine, which is attributed to electron capture and transfer ability of graphene resulting in a more efficient separation of the photoexcited charge carriers from ZnS-graphene composites.

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.

Natural gas use is taking off

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

Kauffmann, B.G.

1995-07-01

The paper describes an infrared radiant heat process to de-ice aircraft. A typical 727 aircraft de-icing costs $2000--3000 using the current glycol method. The natural gas powered heater would only cost $400 per aircraft and would not pose the environmental problems that the glycol does. It is estimated that one Infratek system could consume 3.8 million cubic feet of natural gas each year during the de-icing season. Large airports might have as many as 10 units. 3.8 million cu. ft. of gas is equal to about 40 New York residential customers or eight New York commercial customers.

In vitro terahertz monitoring of muscle tissue dehydration under the action of hyperosmotic agents

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

Kolesnikov, A S; Kolesnikova, E A; Popov, A P

2014-07-31

Dehydration of muscle tissue in vitro under the action of biologically compatible hyperosmotic agents is studied using a laser terahertz spectrometer in the frequency range from 0.25 to 2.5 THz. Broadband terahertz absorption and reflection spectra of the bovine skeletal muscle tissue were obtained under the action of glycerol, polyethylene glycol with the molecular weight 600 (PEG-600), and propylene glycol. The presented results are proposed for application in developing the methods of image contrast enhancement and increasing the depth of biological tissue probing with terahertz radiation. (laser biophotonics)

Investigation on thermo physical characteristics of ethylene glycol based Al:ZnO nanofluids

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

Kiruba, R., E-mail: krbranjini@gmail.com, E-mail: drkingson@karunya.edu; George, Ritty; Gopalakrishnan, M.

2015-06-24

The present work describes the experimental aspects of viscosity and thermal conductivity characteristics of nanofluids. Aluminium doped zinc oxide nanostructures were synthesized by chemical precipitation method. Ultrasonic technique is used to disperse the nanostructures in ethylene glycol. Structural and morphological properties of Al doped ZnO nanostructures are characterized using X-ray diffractometer and scanning electron microscopic technique. The effect of concentration and temperature on thermo-physical properties of Al/ZnO nanofluids is also investigated. The experimental results showed there is enhancement in thermal conductivity with rise in temperature which can be utilized for coolant application.

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.

High Sulfation and a High Molecular Weight Are Important for Anti-hepcidin Activity of Heparin

PubMed Central

Asperti, Michela; Naggi, Annamaria; Esposito, Emiliano; Ruzzenenti, Paola; Di Somma, Margherita; Gryzik, Magdalena; Arosio, Paolo; Poli, Maura

2016-01-01

Heparins are efficient inhibitors of hepcidin expression even in vivo, where they induce an increase of systemic iron availability. Heparins seem to act by interfering with BMP6 signaling pathways that control the expression of liver hepcidin, causing the suppression of SMAD1/5/8 phosphorylation. The anti-hepcidin activity persists also when the heparin anticoagulant property is abolished or reduced by chemical reactions of oxidation/reduction (glycol-split, Gs-Heparins) or by high sulfation (SS-Heparins), but the structural characteristics needed to optimize this inhibitory activity have not been studied in detail. To this aim we analyzed three different heparins (Mucosal Heparin, the Glycol split RO-82, the partially desulfated glycol-split RO-68 and the oversulfated SSLMWH) and separated them in fractions of molecular weight in the range 4–16 kD. Since the distribution of the negative charges in heparins contributes to the activity, we produced 2-O- and 6-O-desulfated heparins. These derivatives were analyzed for the capacity to inhibit hepcidin expression in hepatic HepG2 cells and in mice. The two approaches produced consistent results and showed that the anti-hepcidin activity strongly decreases with molecular weight below 7 kD, with high N-acetylation and after 2-O and 6-O desulfation. The high sulfation and high molecular weight properties for efficient anti-hepcidin activity suggest that heparin is involved in multiple binding sites. PMID:26955355

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

Fabrication of anticoagulation layer on titanium surface by sequential immobilization of poly (ethylene glycol) and albumin.

PubMed

Pan, Chang-Jiang; Hou, Yan-Hua; Zhang, Bin-Bin; Zhang, Lin-Cai

2014-01-01

This paper presents a simple method to sequentially immobilize poly (ethylene glycol) (PEG) and albumin on titanium surface to enhance the blood compatibility. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) analysis indicated that PEG and albumin were successfully immobilized on the titanium surface. Water contact angle results showed a better hydrophilic surface after the immobilization. The immobilized PEG or albumin can not only obviously prevent platelet adhesion and activation but also prolong activated partial thromboplastin time (APTT), leading to the improved anticoagulation. Moreover, immobilization of albumin on PEG-modified surface can further improve the anticoagulation. The approach in the present study provides an effective and efficient method to improve the anticoagulation of blood-contact biomedical devices such as coronary stents.

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.

Laser-triggered release of encapsulated molecules from polylactic-co-glycolic acid microcapsules

NASA Astrophysics Data System (ADS)

Ariyasu, Kazumasa; Ishii, Atsuhiro; Umemoto, Taiga; Terakawa, Mitsuhiro

2016-08-01

The controlled release of encapsulated molecules from a microcapsule is a promising method of targeted drug delivery. Laser-triggered methods for the release of encapsulated molecules have the advantage of spatial and temporal controllability. In this study, we demonstrated the release of encapsulated molecules from biodegradable polymer-based microcapsules using near-infrared femtosecond laser pulses. The polylactic-co-glycolic acid microcapsules encapsulating fluorescein isothiocyanate-dextran molecules were fabricated using a dual-coaxial nozzle system. Irradiation of femtosecond laser pulses enhanced the release of the molecules from the microcapsules, which was accompanied by a decrease in the residual ratio of the microcapsules. The laser-induced modification of the surface of the shell of the microcapsules indicated the potential for sustained release as well as burst release.

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.

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.

Haemoglobinuria caused by propylene glycol in sheep

PubMed Central

Potter, B. J.

1958-01-01

Haemoglobinuria occurred in sheep anaesthetized by an intravenous injection of pentobarbitone sodium containing propylene glycol: an equivalent dose failed to cause haemoglobinuria in rabbits. Intravenous injection of an aqueous solution of 20% propylene glycol caused haemoglobinaemia and haemoglobinuria in sheep. Neither distilled water nor 20% glycerol in water administered under identical conditions produced these effects. Haemoglobinuria occurred on some occasions when an aqueous 20% solution of propylene glycol was administered to sheep after an injection of saline: it never occurred when a solution of 20% propylene glycol prepared with physiological saline was injected. It is suggested that saline may protect against the haemolytic action of propylene glycol in sheep and that propylene glycol should be avoided as a menstruum for pharmaceutical preparations to be used for injection into the blood stream of these animals. PMID:13618540

Evaluation of the Effect of Green Tea Extract on Mouth Bacterial Activity in the Presence of Propylene Glycol

PubMed Central

Moghbel, Abdolhossein; Farjzadeh, Ahmad; Aghel, Nasrin; Agheli, Homaun; Raisi, Nafiseh

2012-01-01

Background Compounds present in green tea have proved to inhibit the growth and activity of bacteria associated with infections. Objectives To assess the effects of green tea leaves extract in presence of propylene glycol on the aerobic mouth bacteria load. Materials and Methods Saliva of 25 volunteer girl students aging 20-25 years were selected and evaluated by a mouthwash sample containing 1% tannin, as the most effective antibacterial complex in green tea. Comparative studies were also conducted between green tea mouthwashes containing 1% tannin and a similar sample with 10% propylene glycol added during extraction. This comparison was applied for a chlorhexidine 0.2% sample as a chemical mouthwash brand, too. Results There was a meaningful difference between the green tea mouthwashes containing 10% propylene glycol and the simple green tea extract (P < 0.05). Significant difference was also seen between the herbal and chemical mouthwashes (P < 0.05). The extract 1% tannin containing 10% propylene glycol reduced the aerobic mouth bacterial load of the student salvia about 64 percent. The pH monotonousness in different days and temperatures approved the stability of tannin in liquid water medium. Conclusions Using green tea extract as a herbal mouthwash is safe and harmless specially for children and pregnant women. This result led us to suppose that green tea may prevent plaque formation on teeth, coming over halitosis due to mouth infection, too. These effects need to be approved in an in vivo trial as a second study. PMID:24624155

Engineering Pseudomonas putida KT2440 for Efficient Ethylene Glycol Utilization

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

Beckham, Gregg T; Franden, Mary A; Thelhawadigedara, Lahiru Niroshan Jayakody

Ethylene glycol is used as a raw material in the production of polyethylene terephthalate, in antifreeze, as a gas hydrate inhibitor in pipelines, and for many other industrial applications. It is metabolized by aerobic microbial processes via the highly toxic intermediates glycolaldehyde and glycolate through C2 metabolic pathways. Pseudomonas putida KT2440, which has been engineered for environmental remediation applications given its high toxicity tolerance and broad substrate specificity, is not able to efficiently metabolize ethylene glycol, despite harboring putative genes for this purpose. To further expand the metabolic portfolio of P. putida, we elucidated the metabolic pathway to enable ethylenemore » glycol via systematic overexpression of glyoxylate carboligase (gcl) in combination with other genes. Quantitative reverse transcription polymerase chain reaction demonstrated that all of the four genes in genomic proximity to gcl (hyi, glxR, ttuD, and pykF) are transcribed as an operon. Where the expression of only two genes (gcl and glxR) resulted in growth in ethylene glycol, improved growth and ethylene glycol utilization were observed when the entire gcl operon was expressed. Both glycolaldehyde and glyoxal inhibit growth in concentrations of ethylene glycol above 50 mM. To overcome this bottleneck, the additional overexpression of the glycolate oxidase (glcDEF) operon removes the glycolate bottleneck and minimizes the production of these toxic intermediates, permitting growth in up to 2 M (~124 g/L) and complete consumption of 0.5 M (31 g/L) ethylene glycol in shake flask experiments. In addition, the engineered strain enables conversion of ethylene glycol to medium-chain-length polyhydroxyalkanoates (mcl-PHAs). Overall, this study provides a robust P. putida KT2440 strain for ethylene glycol consumption, which will serve as a foundational strain for further biocatalyst development for applications in the remediation of waste polyester plastics and biomass-derived wastewater streams.« less

Engineering Pseudomonas putida KT2440 for efficient ethylene glycol utilization.

PubMed

Franden, Mary Ann; Jayakody, Lahiru N; Li, Wing-Jin; Wagner, Neil J; Cleveland, Nicholas S; Michener, William E; Hauer, Bernhard; Blank, Lars M; Wierckx, Nick; Klebensberger, Janosch; Beckham, Gregg T

2018-06-07

Ethylene glycol is used as a raw material in the production of polyethylene terephthalate, in antifreeze, as a gas hydrate inhibitor in pipelines, and for many other industrial applications. It is metabolized by aerobic microbial processes via the highly toxic intermediates glycolaldehyde and glycolate through C2 metabolic pathways. Pseudomonas putida KT2440, which has been engineered for environmental remediation applications given its high toxicity tolerance and broad substrate specificity, is not able to efficiently metabolize ethylene glycol, despite harboring putative genes for this purpose. To further expand the metabolic portfolio of P. putida, we elucidated the metabolic pathway to enable ethylene glycol via systematic overexpression of glyoxylate carboligase (gcl) in combination with other genes. Quantitative reverse transcription polymerase chain reaction demonstrated that all of the four genes in genomic proximity to gcl (hyi, glxR, ttuD, and pykF) are transcribed as an operon. Where the expression of only two genes (gcl and glxR) resulted in growth in ethylene glycol, improved growth and ethylene glycol utilization were observed when the entire gcl operon was expressed. Both glycolaldehyde and glyoxal inhibit growth in concentrations of ethylene glycol above 50 mM. To overcome this bottleneck, the additional overexpression of the glycolate oxidase (glcDEF) operon removes the glycolate bottleneck and minimizes the production of these toxic intermediates, permitting growth in up to 2 M (~124 g/L) and complete consumption of 0.5 M (31 g/L) ethylene glycol in shake flask experiments. In addition, the engineered strain enables conversion of ethylene glycol to medium-chain-length polyhydroxyalkanoates (mcl-PHAs). Overall, this study provides a robust P. putida KT2440 strain for ethylene glycol consumption, which will serve as a foundational strain for further biocatalyst development for applications in the remediation of waste polyester plastics and biomass-derived wastewater streams. Copyright © 2018. Published by Elsevier Inc.

Experimental Evidence for a Hydride Transfer Mechanism in Plant Glycolate Oxidase Catalysis*

PubMed Central

Dellero, Younès; Mauve, Caroline; Boex-Fontvieille, Edouard; Flesch, Valérie; Jossier, Mathieu; Tcherkez, Guillaume; Hodges, Michael

2015-01-01

In plants, glycolate oxidase is involved in the photorespiratory cycle, one of the major fluxes at the global scale. To clarify both the nature of the mechanism and possible differences in glycolate oxidase enzyme chemistry from C3 and C4 plant species, we analyzed kinetic parameters of purified recombinant C3 (Arabidopsis thaliana) and C4 (Zea mays) plant enzymes and compared isotope effects using natural and deuterated glycolate in either natural or deuterated solvent. The 12C/13C isotope effect was also investigated for each plant glycolate oxidase protein by measuring the 13C natural abundance in glycolate using natural or deuterated glycolate as a substrate. Our results suggest that several elemental steps were associated with an hydrogen/deuterium isotope effect and that glycolate α-deprotonation itself was only partially rate-limiting. Calculations of commitment factors from observed kinetic isotope effect values support a hydride transfer mechanism. No significant differences were seen between C3 and C4 enzymes. PMID:25416784

21 CFR 172.765 - Succistearin (stearoyl propylene glycol hydrogen succinate).

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Succistearin (stearoyl propylene glycol hydrogen... Other Specific Usage Additives § 172.765 Succistearin (stearoyl propylene glycol hydrogen succinate). The food additive succistearin (stearoyl propylene glycol hydrogen succinate) may be safely used in...

21 CFR 582.4666 - Propylene glycol.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Propylene glycol. 582.4666 Section 582.4666 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Propylene glycol. (a) Product. Propylene glycol. (b) Conditions of use. This substance is generally...

21 CFR 582.4666 - Propylene glycol.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Propylene glycol. 582.4666 Section 582.4666 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Propylene glycol. (a) Product. Propylene glycol. (b) Conditions of use. This substance is generally...

21 CFR 582.4666 - Propylene glycol.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Propylene glycol. 582.4666 Section 582.4666 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Propylene glycol. (a) Product. Propylene glycol. (b) Conditions of use. This substance is generally...

21 CFR 582.4666 - Propylene glycol.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Propylene glycol. 582.4666 Section 582.4666 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Propylene glycol. (a) Product. Propylene glycol. (b) Conditions of use. This substance is generally...

21 CFR 582.4666 - Propylene glycol.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Propylene glycol. 582.4666 Section 582.4666 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Propylene glycol. (a) Product. Propylene glycol. (b) Conditions of use. This substance is generally...

Glycolic acid physical properties and impurities assessment

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

Lambert, D. P.; Pickenheim, B. R.; Bibler, N. E.

This document has been revised due to recent information that the glycolic acid used in Savannah River National Laboratory (SRNL) experiments contains both formaldehyde and methoxyacetic acid. These impurities were in the glycolic acid used in the testing included in this report and in subsequent testing using DuPont (now called Chemours) supplied Technical Grade 70 wt% glycolic acid. However, these impurities were not reported in earlier revisions. Additional data concerning the properties of glycolic acid have also been added to this report. The Defense Waste Processing Facility (DWPF) is planning to implement a nitric-glycolic acid flowsheets to increase attainment tomore » meet closure commitment dates during Sludge Batch 9. In fiscal year 2009, SRNL was requested to determine the physical properties of formic and glycolic acid blends. Blends of formic acid in glycolic acid were prepared and their physical properties tested. Increasing amounts of glycolic acid led to increases in blend density, viscosity and surface tension as compared to the 90 wt% formic acid that is currently used at DWPF. These increases are small, however, and are not expected to present any difficulties in terms of processing. The effect of sulfur impurities in Technical Grade glycolic acid was studied for its impact on DWPF glass quality. While the glycolic acid specification allows for more sulfate than the current formic acid specification, the ultimate impact is expected to be on the order of 0.033 wt% sulfur in glass. Note that lower sulfur content glycolic acid could likely be procured at some increased cost if deemed necessary. A paper study on the effects of radiation on glycolic acid was performed. The analysis indicates that substitution of glycolic acid for formic acid would not increase the radiolytic production rate of H2 and cause an adverse effect in the Slurry Receipt and Adjustment Tank (SRAT) or Slurry Mix Evaporator (SME) process. It has been cited that glycolic acid solutions that are depleted of O2 when subjected to large radiation doses produced considerable quantities of a non-diffusive polymeric material. Considering a constant air purge is maintained in the SRAT and the solution is continuously mixed, oxygen depletion seems unlikely, however, if this polymer is formed in the SRAT solution, the rheology of the solution may be affected and pumping of the solution may be hindered. However, an irradiation test with a simulated SRAT product supernate containing glycolic acid in an oxygen depleted atmosphere found no evidence of polymerization.« less

Clinical tolerance and efficacy of capryloyl salicylic acid peel compared to a glycolic acid peel in subjects with fine lines/wrinkles and hyperpigmented skin.

PubMed

Oresajo, Christian; Yatskayer, Margarita; Hansenne, Isabelle

2008-12-01

Several chemical agents are currently used to perform superficial peels of the face to reduce facial hyperpigmentation and fine lines/wrinkles. Some of the most commonly used agents are alpha hydroxyl acids, such as glycolic acid (GA), or beta hydroxy acid, such as salicylic acid. This study aims to compare the efficacy of GA to that of a novel derivative of salicylic acid, capryloyl salicylic acid (LHA). In a split-face study, 50 female volunteers between the ages of 35 and 60 years with mild to moderate facial hyperpigmentation and fine lines/wrinkles were randomized and LHA or GA peel was applied to one side of the face. Increasing peel concentrations were applied (5-10% LHA or 20-50% GA) based on the tolerance level of the subjects and clinical observations of an expert dermatologist for 12 weeks at biweekly intervals. Of the 44 volunteers who completed the study, at 12 weeks 41% of LHA-treated and 30% of GA-treated subjects demonstrated significant reduction of fine lines/wrinkles compared to baseline. Forty-six percent of LHA-treated subjects and 34% of GA-treated subjects showed significant reduction of hyperpigmentation compared to baseline. LHA treatment was better than GA peels, although there were no statistically significant differences between the two groups. Five percent to 10% of LHA peel is generally safe and as effective as 20-50% GA peel in reducing facial hyperpigmentation and fine lines/wrinkles.

In vitro antimicrobial and anti-endotoxin action of Zingiber Officinale as auxiliary chemical and medicament combined to calcium hydroxide and chlorhexidine.

PubMed

Valera, Marcia Carneiro; Cardoso, Flávia Goulart da Rosa; Maekawa, Lilian Eiko; Camargo, Carlos Henrique Ribeiro; de Oliveira, Luciane Dias; Carvalho, Cláudio Antônio Talge

2015-01-01

This study was conducted in vitro to compare the effectiveness of Zingiber Officinale as an auxiliary chemical substance followed by placement of different intra-canal medication in removing endotoxins and cultivable micro-organisms from infected root canals. Seventy-two root canals were contaminated with Enterococcus faecalis, Candida albicans and Escherichia coli for 28 days. After, the teeth were instrumented using Zingiber Officinale and divided into six groups according to the intra-canal medication: chlorhexidine gel; calcium hydroxide + chlorhexidine gel; glycolic ginger extract; calcium hydroxide + glycolic ginger extract; calcium hydroxide + saline solution and saline solution (control). Sample collections were performed after root canal contamination (Baseline; S1), after instrumentation (S2), 7 days after instrumentation (S3), after 14 days with intra-canal medication (S4) and 7 days after removal of intra-canal medication (S5). The results were analyzed by the Kruskal-Wallis and Dunn tests. It was observed that in S2 and S3 there was significant reduction of the micro-organisms and the quantity of endotoxins after instrumentation. In samples S4 and S5 there was complete elimination of micro-organisms and significant reduction of endotoxins. It was concluded that Zingiber Officinale as an auxiliary chemical substance was effective on the micro-organisms tested, yet was unable to eliminate the endotoxins. Similarly, the intra-canal medication were effective on micro-organisms, yet did not completely eliminate the endotoxins.

Processes and systems for the production of propylene glycol from glycerol

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

Frye, John G; Oberg, Aaron A; Zacher, Alan H

2015-01-20

Processes and systems for converting glycerol to propylene glycol are disclosed. The glycerol feed is diluted with propylene glycol as the primary solvent, rather than water which is typically used. The diluted glycerol feed is sent to a reactor where the glycerol is converted to propylene glycol (as well as other byproducts) in the presence of a catalyst. The propylene glycol-containing product from the reactor is recycled as a solvent for the glycerol feed.

Polyethylene Glycol-Mediated Synthesis of Cubic Iron Oxide Nanoparticles with High Heating Power

NASA Astrophysics Data System (ADS)

Iacovita, Cristian; Stiufiuc, Rares; Radu, Teodora; Florea, Adrian; Stiufiuc, Gabriela; Dutu, Alina; Mican, Sever; Tetean, Romulus; Lucaciu, Constantin M.

2015-10-01

Iron oxide magnetic nanoparticles (IOMNPs) have been successfully synthesized by means of solvothermal reduction method employing polyethylene glycol (PEG200) as a solvent. The as-synthesized IOMNPs are poly-dispersed, highly crystalline, and exhibit a cubic shape. The size of IOMNPs is strongly dependent on the reaction time and the ration between the amount of magnetic precursor and PEG200 used in the synthesis method. At low magnetic precursor/PEG200 ratio, the cubic IOMNPs coexist with polyhedral IOMNPs. The structure and morphology of the IOMNPs were thoroughly investigated by using a wide range of techniques: TEM, XRD, XPS, FTIR, and RAMAN. XPS analysis showed that the IOMNPs comprise a crystalline magnetite core bearing on the outer surface functional groups from PEG200 and acetate. The presence of physisorbed PEG200 on the IOMNP surface is faintly detected through FT-IR spectroscopy. The surface of IOMNPs undergoes oxidation into maghemite as proven by RAMAN spectroscopy and the occurrence of satellite peaks in the Fe2p XP spectra. The magnetic studies performed on powder show that the blocking temperature (TB) of IOMNPs is around 300 K displaying a coercive field in between 160 and 170 Oe. Below the TB, the field-cooled (FC) curves turn concave and describe a plateau indicating that strong magnetic dipole-dipole interactions are manifested in between IOMNPs. The specific absorption rate (SAR) values increase with decreasing nanoparticle concentrations for the IOMNPs dispersed in water. The SAR dependence on the applied magnetic field, studied up to magnetic field amplitude of 60 kA/m, presents a sigmoid shape with saturation values up to 1700 W/g. By dispersing the IOMNPs in PEG600 (liquid) and PEG1000 (solid), it was found that the SAR values decrease by 50 or 75 %, indicating that the Brownian friction within the solvent was the main contributor to the heating power of IOMNPs.

Organic chemical degradation by remote study of the redox conditions

NASA Astrophysics Data System (ADS)

Fernandez, P. M.; Revil, A.; Binley, A. M.; Bloem, E.; French, H. K.

2014-12-01

Monitoring the natural (and enhanced) degradation of organic contaminants is essential for managing groundwater quality in many parts of the world. Contaminated sites often have limited access, hence non-intrusive methods for studying redox processes, which drive the degradation of organic compounds, are required. One example is the degradation of de-icing chemicals (glycols and organic salts) released to the soil near airport runways during winter. This issue has been broadly studied at Oslo airport, Gardermoen, Norway using intrusive and non-intrusive methods. Here, we report on laboratory experiments that aim to study the potential of using a self-potential, DCresistivity, and time-domain induced polarization for geochemical characterization of the degradation of Propylene Glycol (PG). PG is completely miscible in water, does not adsorb to soil particles and does not contribute to the electrical conductivity of the soil water. When the contaminant is in the unsaturated zone near the water table, the oxygen is quickly consumed and the gas exchange with the surface is insufficient to ensure aerobic degradation, which is faster than anaerobic degradation. Since biodegradation of PG is highly oxygen demanding, anaerobic pockets can exist causing iron and manganese reduction. It is hypothesised that nitrate would boost the degradation rate under such conditions. In our experiment, we study PG degradation in a sand tank. We provide the system with an electron highway to bridge zones with different redox potential. This geo-battery system is characterized by self-potential, resistivity and induced polarization anomalies. An example of preliminary results with self-potential at two different times of the experiment can be seen in the illustration. These will be supplemented with more direct information on the redox chemistry: in-situ water sampling, pH, redox potential and electrical conductivity measurements. In parallel, a series of batch experiments have been performed to study anoxic microbial degradation using gas and resistivity measurements.

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.

Preparation of poly(trimethyl-2-methacroyloxyethylammonium chloride-co-ethylene glycol dimethacrylate) monolith and its application in solid phase microextraction of brominated flame retardants.

PubMed

Yang, Ting-ting; Zhou, Lin-feng; Qiao, Jun-qin; Lian, Hong-zhen; Ge, Xin; Chen, Hong-yuan

2013-05-24

A capillary poly(trimethyl-2-methacroyloxyethylammonium chloride-co-ethylene glycol dimethacrylate) monolith was in situ synthesized by thermally initiated free radical co-polymerization using trimethyl-2-methacroyloxyethylammonium chloride (MATE) and ethylene glycol dimethacrylate (EGDMA) as functional monomer and cross-linker, respectively. N,N-dimethylformamide and polyethylene glycol 6000 were used as solvent and porogen, respectively. The morphology and porous structure of the resulting monoliths were assessed by scanning electron microscope. In order to prepare practically useful poly(MATE-co-EGDMA) monoliths with low flow resistance and good mechanical strength, some parameters such as PEG-6000 to DMF ratio, total monomer to porogen ratio, and crosslinker to monomer ratio were optimized systematically. Moreover, the extraction mechanism was evaluated using two series of compounds, alkylbenzenes and weak acids, as model compounds on poly(MATE-co-EGDMA) monoliths as liquid chromatographic stationary phase. Finally, the monoliths were applied as the solid phase microextraction medium, and a simple off-line method for simultaneous determination of three brominated flame retardants, 2,4,6-tribromophenol (TBP), tetrabromobisphenol A (TBBPA) and 4,4'-dibrominated diphenyl ether (DBDPE), in environmental waters was developed by coupling the polymer monolith microextraction to HPLC with UV detection. The regression equations for these three brominated flame retardants showed good linearity from their limit of quantification to 5000ng/mL. The limits of detection were 0.20, 0.15 and 0.10ng/mL for TBP, TBBPA and DBDPE, respectively. The recovery of the proposed method was 78.7-106.1% with intra-day relative standard deviation of 1.3-4.4%. Copyright © 2013 Elsevier B.V. All rights reserved.

40 CFR 721.3860 - Glycol monobenzoate.

Code of Federal Regulations, 2010 CFR

2010-07-01

... information on methods for protecting against such risk, into an MSDS as described in § 721.72(c) within 90... 721.3860 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES... substance is any manner or method of manufacture, import, or processing associated with any use of this...

40 CFR 63.1275 - Glycol dehydration unit process vent standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 12 2014-07-01 2014-07-01 false Glycol dehydration unit process vent... Storage Facilities § 63.1275 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart that must be controlled for air emissions as...

40 CFR 63.1275 - Glycol dehydration unit process vent standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 12 2013-07-01 2013-07-01 false Glycol dehydration unit process vent... Storage Facilities § 63.1275 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart that must be controlled for air emissions as...

21 CFR 172.765 - Succistearin (stearoyl propylene glycol hydrogen succinate).

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Succistearin (stearoyl propylene glycol hydrogen succinate). 172.765 Section 172.765 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... propylene glycol hydrogen succinate). The food additive succistearin (stearoyl propylene glycol hydrogen...

21 CFR 172.765 - Succistearin (stearoyl propylene glycol hydrogen succinate).

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Succistearin (stearoyl propylene glycol hydrogen succinate). 172.765 Section 172.765 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... propylene glycol hydrogen succinate). The food additive succistearin (stearoyl propylene glycol hydrogen...

21 CFR 172.765 - Succistearin (stearoyl propylene glycol hydrogen succinate).

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Succistearin (stearoyl propylene glycol hydrogen succinate). 172.765 Section 172.765 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... propylene glycol hydrogen succinate). The food additive succistearin (stearoyl propylene glycol hydrogen...

21 CFR 582.1666 - Propylene glycol.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Propylene glycol. 582.1666 Section 582.1666 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1666 Propylene glycol. (a) Product. Propylene glycol. (b) Conditions of use. This substance...

21 CFR 582.1666 - Propylene glycol.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Propylene glycol. 582.1666 Section 582.1666 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1666 Propylene glycol. (a) Product. Propylene glycol. (b) Conditions of use. This substance...

21 CFR 582.1666 - Propylene glycol.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Propylene glycol. 582.1666 Section 582.1666 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1666 Propylene glycol. (a) Product. Propylene glycol. (b) Conditions of use. This substance...

Target-specific cellular uptake of PLGA nanoparticles coated with poly(L-lysine)-poly(ethylene glycol)-folate conjugate.

PubMed

Kim, Sun Hwa; Jeong, Ji Hoon; Chun, Ki Woo; Park, Tae Gwan

2005-09-13

Poly(D,L-lactic-co-glycolic acid) (PLGA) nanoparticles with anionic surface charge were surface coated with cationic di-block copolymer, poly(L-lysine)-poly(ethylene glycol)-folate (PLL-PEG-FOL) conjugate, for enhancing their site-specific intracellular delivery against folate receptor overexpressing cancer cells. The PLGA nanoparticles coated with the conjugate were characterized in terms of size, surface charge, and change in surface composition by XPS. By employing the flow cytometry method and confocal image analysis, the extent of cellular uptake was comparatively evaluated under various conditions. PLL-PEG-FOL coated PLGA nanoparticles demonstrated far greater extent of cellular uptake to KB cells, suggesting that they were mainly taken up by folate receptor-mediated endocytosis. The enhanced cellular uptake was also observed even in the presence of serum proteins, possibly due to the densely seeded PEG chains. The PLL-PEG-FOL coated PLGA nanoparticles could be potentially applied for cancer cell targeted delivery of various therapeutic agents.

Mechanochemical Cycloreversion of Cyclobutane Observed at the Single Molecule Level.

PubMed

Pill, Michael F; Holz, Katharina; Preußke, Nils; Berger, Florian; Clausen-Schaumann, Hauke; Lüning, Ulrich; Beyer, Martin K

2016-08-16

Mechanochemical cycloreversion of cyclobutane is known from ultrasound experiments. It is, however, not clear which forces are required to induce the cycloreversion. In atomic force microscopy (AFM) experiments, on the other hand, it is notoriously difficult to assign the ruptured bond. We have solved this problem through the synthesis of tailored macrocycles, in which the cyclobutane mechanophore is bypassed by an ethylene glycol chain of specific length. This macrocycle is covalently anchored between a glass substrate and an AFM cantilever by polyethylene glycol linkers. Upon mechanical stretching of the macrocycle, cycloreversion occurs, which is identified by a defined length increase of the stretched polymer. The measured length change agrees with the value calculated with the external force explicitly included (EFEI) method. By using two different lengths for the ethylene glycol safety line, the assignment becomes unambiguous. Mechanochemical cycloreversion of cyclobutane is observed at forces above 1.7 nN. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Temperature dependent viscosity of cobalt ferrite / ethylene glycol ferrofluids

NASA Astrophysics Data System (ADS)

Kharat, Prashant B.; Somvanshi, Sandeep B.; Kounsalye, Jitendra S.; Deshmukh, Suraj S.; Khirade, Pankaj P.; Jadhav, K. M.

2018-04-01

In the present work, cobalt ferrite / ethylene glycol ferrofluid is prepared in 0 to 1 (in the step of 0.2) volume fraction of cobalt ferrite nanoparticles synthesized by co-precipitation method. The XRD results confirmed the formation of single phase spinel structure. The Raman spectra have been deconvoluted into individual Lorentzian peaks. Cobalt ferrite has cubic spinel structure with Fd3m space group. FT-IR spectra consist of two major absorption bands, first at about 586 cm-1 (υ1) and second at about 392 cm-1 (υ2). These absorption bands confirm the formation of spinel-structured cobalt ferrite. Brookfield DV-III viscometer and programmable temperature-controlled bath was used to study the relationship between viscosity and temperature. Viscosity behavior with respect to temperature has been studied and it is revealed that the viscosity of cobalt ferrite / ethylene glycol ferrofluids increases with an increase in volume fraction of cobalt ferrite. The viscosity of the present ferrofluid was found to decrease with increase in temperature.

Transesterification of propylene glycol methyl ether in chromatographic reactors using anion exchange resin as a catalyst.

PubMed

Oh, Jungmin; Sreedhar, Balamurali; Donaldson, Megan E; Frank, Timothy C; Schultz, Alfred K; Bommarius, Andreas S; Kawajiri, Yoshiaki

2016-09-30

Reactive chromatography using an anion exchange resin is proposed for a transesterification reaction of propylene glycol methyl ether (DOWANOL™ PM) with ethyl acetate to produce propylene glycol methyl ether acetate (DOWANOL™ PMA). This reaction is studied in batch and chromatographic reactors catalyzed by an anion exchange resin. Several anion exchange resins are tested and compared based on the performance of resin as an adsorbent and a catalyst. A chromatographic column is packed with a selected catalyst, AMBERLITE™ IRA904, and both reaction and chromatographic elution are studied at different temperatures and feed concentrations. The resulting chromatograms are fitted to a mathematical model to obtain adsorption equilibrium and reaction kinetic parameters by the inverse method. Compared to esterification investigated in a previous study, transesterification has advantages such as a higher conversion at lower temperature and easy removal of the byproduct which may lead to higher productivity. Deactivation of anion exchange resins is observed and potential solutions are suggested. Copyright © 2016 Elsevier B.V. All rights reserved.

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.

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

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.

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.

A new apparatus for real-time assessment of the particle size distribution of disintegrating tablets.

PubMed

Quodbach, Julian; Kleinebudde, Peter

2014-11-01

The aim of this study is the introduction of a novel apparatus that is capable of continuously measuring the particle size reduction of disintegrating tablets and analysis of the obtained results. The apparatus is constructed such that no particles pass directly through the pumping system. Thereby, the overall energy input into the particle suspension is reduced, and continuous measurement is possible without rapid destruction of the generated particles. The detected particle sizes at the beginning and at the end of the measurement differ greatly, depending on the applied disintegrant. The median particle sizes at the end of the measurement vary between 621.5 and 178.0 μm for different disintegrants. It is demonstrated that the particle size reduction follows an exponential function and that the fit parameters can be used to describe the disintegration behavior. A strong correlation between the median particle size of crospovidone disintegrants and generated particle size of the tablets is observed. This could be due to a more homogeneous distribution of the disintegrant particles in the tablets. Similar trends are observed for sodium starch glycolate and croscarmellose sodium. The new apparatus provides an innovative method to describe disintegrant effectiveness and efficiency. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

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.

Reformulating Polycaprolactone Fumarate to Eliminate Toxic Diethylene Glycol: Effects of Polymeric Branching and Autoclave Sterilization on Material Properties

PubMed Central

Runge, M. Brett; Wang, Huan; Spinner, Robert J; Windebank, Anthony J; Yaszemski, Michael J.

2011-01-01

Polycaprolactone fumarate (PCLF) is a cross-linkable derivate of polycaprolactone diol that has been shown to be an effective nerve conduit material that supports regeneration across segmental nerve defects and has warranted future clinical trials. Degradation of the previously studied PCLF (PCLFDEG) releases toxic small molecules of diethylene glycol used as the initiator for the synthesis of polycaprolactone diol. In an effort to eliminate this toxic degradation product we present a strategy for the synthesis of PCLF from either propylene glycol (PCLFPPD) or glycerol (PCLFGLY). PCLFPPD is linear and resembles the previously studied PCLFDEG, while PCLFGLY is branched and exhibits dramatically different material properties. The synthesis and characterization of their thermal, rheological, and mechanical properties are reported. The results show that the linear PCLFPPD has material properties similar to the previously studied PCLFDEG. The branched PCLFGLY exhibits dramatically lower crystalline properties resulting in lower rheological and mechanical moduli, and is therefore a more compliant material. In addition, the question of an appropriate FDA approvable sterilization method is addressed. This study shows that autoclave sterilization on PCLF materials is an acceptable sterilization method for cross-linked PCLF and has minimal effect on the PCLF thermal and mechanical properties. PMID:21911087

Propylene Glycol Poisoning From Excess Whiskey Ingestion: A Case of High Osmolal Gap Metabolic Acidosis.

PubMed

Cunningham, Courtney A; Ku, Kevin; Sue, Gloria R

2015-01-01

In this report, we describe a case of high anion gap metabolic acidosis with a significant osmolal gap attributed to the ingestion of liquor containing propylene glycol. Recently, several reports have characterized severe lactic acidosis occurring in the setting of iatrogenic unintentional overdosing of medications that use propylene glycol as a diluent, including lorazepam and diazepam. To date, no studies have explored potential effects of excess propylene glycol in the setting of alcohol intoxication. Our patient endorsed drinking large volumes of cinnamon flavored whiskey, which was likely Fireball Cinnamon Whisky. To our knowledge, this is the first case of propylene glycol toxicity from an intentional ingestion of liquor containing propylene glycol.

Propylene Glycol Poisoning From Excess Whiskey Ingestion

PubMed Central

Ku, Kevin; Sue, Gloria R.

2015-01-01

In this report, we describe a case of high anion gap metabolic acidosis with a significant osmolal gap attributed to the ingestion of liquor containing propylene glycol. Recently, several reports have characterized severe lactic acidosis occurring in the setting of iatrogenic unintentional overdosing of medications that use propylene glycol as a diluent, including lorazepam and diazepam. To date, no studies have explored potential effects of excess propylene glycol in the setting of alcohol intoxication. Our patient endorsed drinking large volumes of cinnamon flavored whiskey, which was likely Fireball Cinnamon Whisky. To our knowledge, this is the first case of propylene glycol toxicity from an intentional ingestion of liquor containing propylene glycol. PMID:26904700

Clean fuels from bioconversion of solar energy. Annual report, 21 January 1980-20 January 1981

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

Feighner, S.D.; Sikka, H.C.

1981-03-01

The study seeks to enhance glycolic acid excretion by unicellular algae. The strains of algae selected to evaluate glycolic acid accumulation in culture medium were: Chlorella pyrenoidosa (UTEX 395), Chlamydomonas reinhardtii (UTEX 89), Scenedesmus obliquus (UTEX 393), and Ankistrodesmus braunii (UTEX 245). C. pyrenoidosa and C. reinhardtii, based on the amount of glycolic acid produced, were selected for further study. Initial experiments were conducted to measure the effect of different environmental growth conditions on the rate of glycolic accumulation in defined culture medium. The most pronounced effect on glycolic acid excretion was obtained by varying the concentration of carbon dioxidemore » in air. At 1% CO2 in air, C. pyrenoidosa accumulated 5.2 ppm glycolic acid in culture medium. Neither the pH of the culture medium nor the incubation temperature affected glycolic acid accumulation by growing C. pyrenoidosa cultures.« less

Control of Mechanical Properties of Thermoplastic Polyurethane Elastomers by Restriction of Crystallization of Soft Segment

PubMed Central

Kojio, Ken; Furukawa, Mutsuhisa; Nonaka, Yoshiteru; Nakamura, Sadaharu

2010-01-01

Mechanical properties of thermoplastic polyurethane elastomers based on either polyether or polycarbonate (PC)-glycols, 4,4’-dipheylmethane diisocyanate (1,1’-methylenebis(4-isocyanatobenzene)), 1,4-butanediol, were controlled by restriction of crystallization of polymer glycols. For the polyether glycol based-polyurethane elastomers (PUEs), poly(oxytetramethylene) glycol (PTMG), and PTMG incorporating dimethyl groups (PTG-X) and methyl side groups (PTG-L) were employed as a polymer glycol. For the PC-glycol, the randomly copolymerized PC-glycols with hexamethylene (C6) and tetramethylene (C4) units between carbonate groups with various composition ratios (C4/C6 = 0/100, 50/50, 70/30 and 90/10) were employed. The degree of microphase separation and mechanical properties of both the PUEs were investigated using differential scanning calorimetry, dynamic viscoelastic property measurements and tensile testing. Mechanical properties could be controlled by changing the molar ratio of two different monomer components. PMID:28883371

GLYCOL DEHYDRATOR BTEX AND VOC EMISSIONS TESTING RESULTS AT TWO UNITS IN TEXAS AND LOUISIANA VOL. II: APPENDICES

EPA Science Inventory

The report gives results of the collection of emissions test data st two triethylene glycol units to provide data for the comparison to GRI-GLYCalc, a computer program developed to estimate emissions from glycol dehydrators. [NOTE: Glycol dehydrators are used in the natural gas i...

GLYCOL DEHYDRATOR BTEX AND VOC EMISSIONS TESTING RESULTS AT TWO UNITS IN TEXAS AND LOUISIANA VOL. I: TECHNICAL REPORT

EPA Science Inventory

The report gives results of the collection of emissions tests data at two triethylene glycol units to provide data for comparison to GRI-GLYCalc, a computer program developed to estimate emissions from glycol dehydrators. (NOTE: Glycol dehydrators are used in the natural gas indu...

40 CFR 63.1275 - Glycol dehydration unit process vent standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 12 2012-07-01 2011-07-01 true Glycol dehydration unit process vent... Facilities § 63.1275 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

40 CFR 63.1275 - Glycol dehydration unit process vent standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Glycol dehydration unit process vent... Facilities § 63.1275 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

40 CFR 63.765 - Glycol dehydration unit process vent standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Glycol dehydration unit process vent... Facilities § 63.765 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart that must be controlled for air emissions as specified in either...

40 CFR 63.765 - Glycol dehydration unit process vent standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Glycol dehydration unit process vent... Facilities § 63.765 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

40 CFR 63.765 - Glycol dehydration unit process vent standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Glycol dehydration unit process vent... Facilities § 63.765 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart that must be controlled for air emissions as specified in either...

40 CFR 63.765 - Glycol dehydration unit process vent standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Glycol dehydration unit process vent... Facilities § 63.765 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

40 CFR 63.1275 - Glycol dehydration unit process vent standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Glycol dehydration unit process vent... Facilities § 63.1275 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

40 CFR 63.765 - Glycol dehydration unit process vent standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Glycol dehydration unit process vent... Facilities § 63.765 Glycol dehydration unit process vent standards. (a) This section applies to each glycol dehydration unit subject to this subpart with an actual annual average natural gas flowrate equal to or...

21 CFR 172.850 - Lactylated fatty acid esters of glycerol and propylene glycol.

Code of Federal Regulations, 2014 CFR

2014-04-01

... propylene glycol. 172.850 Section 172.850 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... CONSUMPTION Multipurpose Additives § 172.850 Lactylated fatty acid esters of glycerol and propylene glycol. The food additive lactylated fatty acid esters of glycerol and propylene glycol may be safely used in...

21 CFR 172.850 - Lactylated fatty acid esters of glycerol and propylene glycol.

Code of Federal Regulations, 2012 CFR

2012-04-01

... propylene glycol. 172.850 Section 172.850 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... esters of glycerol and propylene glycol. The food additive lactylated fatty acid esters of glycerol and propylene glycol may be safely used in food in accordance with the following prescribed conditions: (a) The...

21 CFR 172.850 - Lactylated fatty acid esters of glycerol and propylene glycol.

Code of Federal Regulations, 2013 CFR

2013-04-01

... propylene glycol. 172.850 Section 172.850 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... esters of glycerol and propylene glycol. The food additive lactylated fatty acid esters of glycerol and propylene glycol may be safely used in food in accordance with the following prescribed conditions: (a) The...

40 CFR 180.1040 - Ethylene glycol; exemption from the requirement of a tolerance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Ethylene glycol; exemption from the... Exemptions From Tolerances § 180.1040 Ethylene glycol; exemption from the requirement of a tolerance. Ethylene glycol as a component of pesticide formulations is exempt from the requirement of a tolerance when...

The effect of materials selection on metals reduction in propylene glycol methyl ether acetate, PGMEA

NASA Astrophysics Data System (ADS)

Entezarian, Majid; Geiger, Bob

2016-03-01

The trend in microelectronics fabrication is to produce nano-features measuring down to 10 nm and finer. The PPT levels of organic and inorganic contaminants in the photoresist, solvent and cleaning solutions are becoming a major processing variable affecting the process capability and defectivity. The photoresist usually contains gels, metals, and particulates that could interfere with the lithography process and cause microbridging defects. Nano filters of 5 nm polypropylene, 5 nm polyethylene, and 10 nm natural nylon were used to filter propylene glycol methyl ether acetate PGMEA containing 50 ppb of Na, Mg, Al, Ca, Cr, Mn, Fe, Cu, Zn, and Pb. All filters were effective in removing trivalent Al, Cr, and Fe metals indicating the mechanism for their removal as mechanical sieving. However, the nylon was also very effective in removing the divalent metals showing adsorptive properties. Furthermore, the metal removal of the nylon membrane was studied as a function of surface chemistry. Natural and charged 40 nm nylon membranes were tested and found that charged nylon is more effective for metal removal.

Injectable dual redox responsive diselenide-containing poly(ethylene glycol) hydrogel.

PubMed

Gong, Chu; Shan, Meng; Li, Bingqiang; Wu, Guolin

2017-09-01

An injectable dual redox responsive diselenide-containing poly(ethylene glycol) (PEG) hydrogel was successfully developed by combining the conceptions of injectable hydrogels and dual redox responsive diselenides. In the first step, four-armed PEG was modified with N-hydroxysuccinimide (NHS)-activated esters and thereafter, crosslinked by selenocystamine crosslinkers to form injectable hydrogels via the rapid reaction between NHS-activated esters and amino groups. The cross-sectional morphology, mechanical properties, and crosslinking modes of hydrogels were well characterized via scanning electron microscope (SEM), rheological measurements, and Fourier transform infrared spectra, respectively. In addition, the oxidation- and reduction-responsive degradation behaviors of hydrogels were observed and analyzed. The model drug, rhodamine B, was encapsulated in the hydrogel. The drug-loaded hydrogel exhibited a dual redox responsive release profile, which was consistent with the degradation experiments. The results of all experiments indicated that the formulated injectable dual redox responsive diselenide-containing PEG hydrogel can have potential applications in various biomedical fields such as drug delivery and stimuli-responsive drug release. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2451-2460, 2017. © 2017 Wiley Periodicals, Inc.

Prediction and validation of the duration of hemodialysis sessions for the treatment of acute ethylene glycol poisoning.

PubMed

Iliuta, Ioan-Andrei; Lachance, Philippe; Ghannoum, Marc; Bégin, Yannick; Mac-Way, Fabrice; Desmeules, Simon; De Serres, Sacha A; Julien, Anne-Sophie; Douville, Pierre; Agharazii, Mohsen

2017-08-01

The duration of hemodialysis (HD) sessions for the treatment of acute ethylene glycol poisoning is dependent on concentration, the operational parameters used during HD, and the presence and severity of metabolic acidosis. Ethylene glycol assays are not readily available, potentially leading to undue extension or premature termination of HD. We report a prediction model for the duration of high-efficiency HD sessions based retrospectively on a cohort study of 26 cases of acute ethylene glycol poisoning in 24 individuals treated by alcohol dehydrogenase competitive inhibitors, cofactors and HD. Two patients required HD for more than 14 days, and two died. In 19 cases, the mean ethylene glycol elimination half-life during high-efficiency HD was 165 minutes (95% confidence interval of 151-180 minutes). In a training set of 12 patients with acute ethylene glycol poisoning, using the 90th percentile half-life (195 minutes) and a target ethylene glycol concentration of 2 mmol/l (12.4 mg/dl) allowed all cases to reach a safe ethylene glycol under 3 mmol/l (18.6 mg/dl). The prediction model was then validated in a set of seven acute ethylene glycol poisonings. Thus, the HD session time in hours can be estimated using 4.7 x (Ln [the initial ethylene glycol concentration (mmol/l)/2]), provided that metabolic acidosis is corrected. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

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...

Repair of damaged DNA in-vivo. Comprehensive progress report, August 1980-August 1983

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

Hanawalt, P.C.

1983-07-01

We have extended our characterization of long patch excision repair (LPER) and have demonstrated that LPER is not mutagenic (or error-prone); that the recA function is required for LPER, at least for its regulation; that the substrate for LPER is produced as a linear (not an exponential) function of uv (254 nm) dose; and that LPER can occur in uvr/sup -/ cells treated with N-methyl-N-nitro-N-nitrosoguanidine (MNNG). We have developed 3 methods for measuring the frequency of interstrand crosslinks in DNA and are now applying these methods to the study of the formation and repair of DNA crosslinks in E.Coli. Wemore » have developed a monoclonal antibody specific for thymine glycol in DNA, and are using it to study the repair of thymine glycol in E. coli.« less

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.

High performance hydrophobic solvent, carbon dioxide capture

DOEpatents

Nulwala, Hunaid; Luebke, David

2017-05-09

Methods and compositions useful, for example, for physical solvent carbon capture. A method comprising: contacting at least one first composition comprising carbon dioxide with at least one second composition to at least partially dissolve the carbon dioxide of the first composition in the second composition, wherein the second composition comprises at least one siloxane compound which is covalently modified with at least one non-siloxane group comprising at least one heteroatom. Polydimethylsiloxane (PDMS) materials and ethylene-glycol based materials have high carbon dioxide solubility but suffer from various problems. PDMS is hydrophobic but suffers from low selectivity. Ethylene-glycol based systems have good solubility and selectivity, but suffer from high affinity to water. Solvents were developed which keep the desired combinations of properties, and result in a simplified, overall process for carbon dioxide removal from a mixed gas stream.

Tailoring of processing parameters for sintering microsphere-based scaffolds with dense-phase carbon dioxide

PubMed Central

Jeon, Ju Hyeong; Bhamidipati, Manjari; Sridharan, BanuPriya; Scurto, Aaron M.; Berkland, Cory J.; Detamore, Michael S.

2015-01-01

Microsphere-based polymeric tissue-engineered scaffolds offer the advantage of shape-specific constructs with excellent spatiotemporal control and interconnected porous structures. The use of these highly versatile scaffolds requires a method to sinter the discrete microspheres together into a cohesive network, typically with the use of heat or organic solvents. We previously introduced subcritical CO2 as a sintering method for microsphere-based scaffolds; here we further explored the effect of processing parameters. Gaseous or subcritical CO2 was used for making the scaffolds, and various pressures, ratios of lactic acid to glycolic acid in poly(lactic acid-co-glycolic acid), and amounts of NaCl particles were explored. By changing these parameters, scaffolds with different mechanical properties and morphologies were prepared. The preferred range of applied subcritical CO2 was 15–25 bar. Scaffolds prepared at 25 bar with lower lactic acid ratios and without NaCl particles had a higher stiffness, while the constructs made at 15 bar, lower glycolic acid content, and with salt granules had lower elastic moduli. Human umbilical cord mesenchymal stromal cells (hUCMSCs) seeded on the scaffolds demonstrated that cells penetrate the scaffolds and remain viable. Overall, the study demonstrated the dependence of the optimal CO2 sintering parameters on the polymer and conditions, and identified desirable CO2 processing parameters to employ in the sintering of microsphere-based scaffolds as a more benign alternative to heat-sintering or solvent-based sintering methods. PMID:23115065

Solvent directed morphologies and enhanced luminescent properties of BaWO4:Tm3+,Dy3+ for white light emitting diodes

NASA Astrophysics Data System (ADS)

Wu, Hongyue; Yang, Junfeng; Wang, Xiaoxue; Gan, Shucai; Li, Linlin

2018-05-01

A series of Tm3+ and Dy3+ codoped BaWO4 phosphors with tunable shapes were controllably synthesized by a facile solvothermal method. The effects of ratio of ethylene glycol (EG) and water on the morphologies of BaWO4 structures are systematically studied. It was discovered that the reason for these morphological changes is based on the reaction speed of the kinetic control, which relates to the strong chelating abilities of ethylene glycol. And when the solvent is pure ethylene glycol, the peanut-like BaWO4:Dy3+ has the strongest emission intensity. Moreover, the emission color of the phosphors varied from blue (0.232, 0.180) to white (0.268, 0.250) by controlling Dy3+ ions content with a fixed Tm3+ concentration. The energy transfer mechanism was investigated in detail. With increasing the doped concentration of Dy3+ ions, the energy transfer efficiency of BaWO4:0.005Tm3+,yDy3+ increased gradually and reached as high as 63% when the Dy3+ doped concentration is 0.03. The critical distance RC calculated by the spectral overlap method is about 19.93 Å, and it is in good agreement with that obtained using the concentration quenching method (19.70 Å), indicating that the electric dipole-dipole interaction is the main energy transfer mechanism for BaWO4:Tm3+,Dy3+ phosphors.

Luminescence study of Eu3+ doped GdVO4 nanoparticles: Concentration, particle size, and core/shell effects

NASA Astrophysics Data System (ADS)

Singh, N. Shanta; Ningthoujam, R. S.; Devi, L. Romila; Yaiphaba, N.; Sudarsan, V.; Singh, S. Dorendrajit; Vatsa, R. K.; Tewari, R.

2008-11-01

Nanoparticles of GdVO4 doped with Eu3+ and core/shell of GdVO4:Eu3+/GdVO4 are prepared by urea hydrolysis method using ethylene glycol as capping agent as well as reaction medium at 130 °C. Unit cell volume increases when GdVO4 is doped with Eu3+ indicating the substitution of Gd3+ lattice sites by Eu3+. From luminescence study, it is confirmed that there is no particle size effect on emission positions of Eu3+. Optimum luminescence intensity is found to be in 5-10 at. % Eu3+. Above these concentrations, luminescence intensity decreases due to concentration quenching effect. There is an enhancement in luminescence intensity of core/shell nanoparticles. This has been attributed to the reduction in surface inhomogenities of Eu3+ surroundings by bonding to GdVO4 shell. The lifetime for D50 level increases with annealing and core/shell formation.

Facile fabrication of high-quality Ag/PS coaxial nanocables based on the mixed mode of soft/hard templates

PubMed Central

Wan, Mimi; Zhao, Wenbo; Peng, Fang; Wang, Qi; Xu, Ping; Mao, Chun; Shen, Jian

2016-01-01

A new kind of high-quality Ag/PS coaxial nanocables can be facilely synthesized by using soft/hard templates method. In order to effectively introduce Ag sources into porous polystyrene (PS) nanotubes which were trapped in porous anodic aluminum oxide (AAO) hard template, Pluronic F127 (F127) was used as guiding agent, soft template and reductant. Meanwhile, ethylene glycol solution was also used as solvent and co-reducing agent to assist in the formation of silver nanowires. The influences of concentration of F127 and reducing reaction time on the formation of Ag/PS coaxial nanocables were discussed. Results indicated that the high-quality Ag/PS coaxial nanocables can be obtained by the mixed mode of soft/hard templates under optimized conditions. This strategy is expected to be extended to design more metal/polymer coaxial nanocables for the benefit of creation of complex and functional nanoarchitectures and components. PMID:27477888

Monetite formed in mixed solvents of water and ethylene glycol and its transformation to hydroxyapatite.

PubMed

Ma, Ming-Guo; Zhu, Ying-Jie; Chang, Jiang

2006-07-27

Agglomerated nanorods of hydroxyapatite have been synthesized using monetite as a precursor in a NaOH solution. Monetite consisting of nanosheets has been successfully synthesized by a one-step microwave-assisted method using CaCl(2).2.5H(2)O, NaH(2)PO(4), and sodium dodecyl sulfate (SDS) in water/ethylene glycol (EG) mixed solvents. The effects of the molar ratio of water to EG and the reaction time on the products were investigated. The products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared spectrometry (FTIR).

Enantiomeric Recognition of Organic Ammonium Salts by Chiral Dialkyl-, Dialkenyl-, and Tetramethyl-Substituted Pyridino-18-Crown-6 and Tetramethyl- Substituted Bis-Pyridino-18-Crown-6 Ligands: Comparison of Temperature-Dependent 1H NMR and Empirical Force Field Techniques

DTIC Science & Technology

1990-04-18

COVERED 14, DATE OF REPORT (Year. Month, Day) 15. PAGE COUNT Interim FROM _ _ TO April 18, 1990 16. SUPPLEMENTARY NOTATION 17 , COSATI CODES 18. SUBJECT...to epoxide 17 was carried out ,o by using the method of Koppenhoefer and Schurig.241-2 Our epoxides 17 where R was isopropyl, isobutyl, and Scheme i... 17 with diethylene glycol and a catalytic amount of sodium was carried out as reported for the preparation of the chiral dimethyl- tetraethylene glycol

A Deceptively Simple Solution for Refractory Melasma: Glycolic Acid Peels and Hydroquinone at Home

PubMed Central

Oka, Aiko; Osawa, Ema; Koshima, Isao

2017-01-01

Summary: Although various treatment methods for melasma have developed, substantial improvement of the condition is sometimes difficult. We have experientially found that some of refractory melasma caused by daily friction can easily be treated by using a combination of a peeling agent (20% glycolic acid) and a depigmenting agent (5% hydroquinone) twice daily at home. And here, by performing skin biopsies, we revealed the pathological mechanism: hyperkeratosis caused by repeated physical stimulus, which prevents infiltration of topical therapeutic agents, was dramatically reduced by chemical peeling, resulting that the melanin pigments were effectively cleared by topical hydroquinone. PMID:28607861

Shedding PEG Palisade by Temporal Photostimulation and Intracellular Reducing Milieu for Facilitated Intracellular Trafficking and DNA Release.

PubMed

Wang, Tieyan; Chen, Qixian; Lu, Hongguang; Li, Wei; Li, Zaifen; Ma, Jianbiao; Gao, Hui

2016-08-17

The dilemma of poly(ethylene glycol) surface modification (PEGylation) inspired us to develop an intracellularly sheddable PEG palisade for synthetic delivery systems. Here, we attempted to conjugate PEG to polyethylenimine (PEI) through tandem linkages of disulfide-bridge susceptible to cytoplasmic reduction and an azobenzene/cyclodextrin inclusion complex responsive to external photoirradiation. The subsequent investigations revealed that facile PEG detachment could be achieved in endosomes upon photoirradiation, consequently engendering exposure of membrane-disruptive PEI for facilitated endosome escape. The liberated formulation in the cytosol was further subjected to complete PEG detachment relying on disulfide cleavage in the reductive cytosol, thus accelerating dissociation of electrostatically assembled PEI/DNA polyplex to release DNA by means of polyion exchange reaction with intracellularly charged species, ultimately contributing to efficient gene expression.

Surfactant free graphene nanosheets based nanofluids by in-situ reduction of alkaline graphite oxide suspensions

NASA Astrophysics Data System (ADS)

Jyothirmayee Aravind, S. S.; Ramaprabhu, S.

2011-12-01

Herein we report an entirely different route for the synthesis of graphene nanosheets (GNs) based nanofluids without surfactant or harsh chemical treatments, by reducing the alkaline graphite oxide suspension in ethylene glycol (EG) and de-ionized (DI) water based fluids by a simple thermal treatment. The thermal conductivity measurement after the reduction shows about 6.5 and 13.6% enhancements at 25 °C for the 0.14% volume fraction of GN in EG and DI water, respectively, which is ascribed to the high aspect ratio of the GNs. In addition, a large enhancement in the electrical conductivity of EG and DI water based reduced nanofluids is observed. This interesting result is attributed to the high electrical conductivity of reduced graphene nanosheets suspensions.

Comparative studies on structural properties and antimicrobial potential of spinel ferrite nanoparticles synthesized using various methods

NASA Astrophysics Data System (ADS)

Baraliya, Jagdish D.; Rakhashiya, Purvi M.; Patel, Pooja P.; Thaker, Vrinda S.; Joshi, Hiren H.

2017-05-01

In this study, novel multifunctional magnetic iron-based nanoparticles (CoFe2O4) coated with silica, silica-DEG (diethylene glycol), PEG (polyethylene glycol) were synthesized using Auto Combustion Method (ACM), Co-precipitation Method (COPM), Citrate Precursor Method (CPM), Flash Combustion Method (FCM). These spinel ferrite nanoparticles also contain very high antibacterial properties to fulfill the requirements of a drug delivery system so that the antibiotic concentration could be minimized. A potential delivery system could be based on a ferromagnetic fluid. The effects of various preparation methods on the physical properties of the nanoparticles were examined. The nanoparticles were also tested against four human pathogenic bacteria (Gram negative E.coli, P. aeruginosa, Gram positive S. aureus, S. pyogenus) and two fungi (C. albicans, A.niger). It was revealed that a nanoparticle has strong antibacterial activity as compared to antifungal. Further, Gram positive bacteria are more affected than Gram negative bacteria. It was also clear that different methods of coating have great influence on the antimicrobial properties. It was observed that these nanoparticles have significantly different but potentially very high antimicrobial activities against the tested organisms than found elsewhere by other nanoparticles on the same organisms.

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.

18F-labeled Rhodamines as Potential Myocardial Perfusion Agents: Comparison of Pharmacokinetic Properties of Several Rhodamines

PubMed Central

Bartholoma, Mark D.; Zhang, Shaohui; Akurathi, Vamsidhar; Pacak, Christina A.; Dunning, Patricia; Fahey, Frederic H.; Cowan, Douglas B.; Treves, S. Ted; Packard, Alan B.

2015-01-01

Introduction We recently reported the development of the [18F]fluorodiethylene glycol ester of rhodamine B as a potential positron emission tomography (PET) tracer for myocardial perfusion imaging (MPI). This compound was developed by optimizing the ester moiety on the rhodamine B core, and its pharmacokinetic properties were found to be superior to those of the prototype ethyl ester. The goal of the present study was to optimize the rhodamine core while retaining the fluorodiethyleneglycol ester prosthetic group. Methods A series of different rhodamine cores (rhodamine 6G, rhodamine 101, and tetramethylrhodamine) were labeled with 18F using the corresponding rhodamine lactones as the precursors and [18F]fluorodiethylene glycol ester as the prosthetic group. The compounds were purified by semipreparative HPLC, and their biodistribution was measured in rats. Additionally, the uptake of the compounds was evaluated in isolated rat cardiomyocytes. Results As was the case with the different prosthetic groups, we found that the rhodamine core has a significant effect on the in vitro and in vivo properties of this series of compounds. Of the rhodamines evaluated to date, the pharmacologic properties of the 18F-labeled diethylene glycol ester of rhodamine 6G are superior to those of the 18F-labeled diethylene glycol esters of rhodamine B, rhodamine 101, and tetramethylrhodamine. As with 18F-labeled rhodamine B, [18F]rhodamine 6G was observed to localize in the mitochondria of isolated rat cardiomyocytes. Conclusions Based on these results, the 18F-labeled diethylene glycol ester of rhodamine 6G is the most promising potential PET MPI radiopharmaceutical of those that have been evaluated to date, and we are now preparing to carry out first-in-human clinical studies with this compound. PMID:26205075

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.

Highly selective separation of carbon dioxide from nitrogen and methane by nitrile/glycol-difunctionalized ionic liquids in supported ionic liquid membranes (SILMs).

PubMed

Hojniak, Sandra D; Silverwood, Ian P; Khan, Asim Laeeq; Vankelecom, Ivo F J; Dehaen, Wim; Kazarian, Sergei G; Binnemans, Koen

2014-07-03

Novel difunctionalized ionic liquids (ILs) containing a triethylene glycol monomethyl ether chain and a nitrile group on a pyrrolidinium or imidazolium cation have been synthesized and incorporated into supported ionic liquid membranes (SILMs). These ILs exhibit ca. 2.3 times higher CO2/N2 and CO2/CH4 gas separation selectivities than analogous ILs functionalized only with a glycol chain. Although the glycol moiety ensures room temperature liquidity of the pyrrolidinium and imidazolium ILs, the two classes of ILs benefit from the presence of a nitrile group in different ways. The difunctionalized pyrrolidinium ILs exhibit an increase in CO2 permeance, whereas the permeances of the contaminant gases rise negligibly, resulting in high gas separation selectivities. In the imidazolium ILs, the presence of a nitrile group does not always increase the CO2 permeance nor does it increase the CO2 solubility, as showed in situ by the ATR-FTIR spectroscopic method. High selectivity of these ILs is caused by the considerably reduced permeances of N2 and CH4, most likely due to the ability of the -CN group to reject the nonpolar contaminant gases. Apart from the CO2 solubility, IL-CO2 interactions and IL swelling were studied with the in situ ATR-FTIR spectroscopy. Different strengths of the IL-CO2 interactions were found to be the major difference between the two classes of ILs. The difunctionalized ILs interacted stronger with CO2 than the glycol-functionalized ILs, as manifested in the smaller bandwidths of the bending mode band of CO2 for the latter.

The Effects of Topically Applied Glycolic Acid and Salicylic Acid on Ultraviolet Radiation-Induced Erythema, DNA Damage and Sunburn Cell Formation in Human Skin

PubMed Central

Kornhauser, Andrija; Wei, Rong-Rong; Yamaguchi, Yuji; Coelho, Sergio G.; Kaidbey, Kays; Barton, Curtis; Takahashi, Kaoruko; Beer, Janusz Z.; Miller, Sharon A.; Hearing, Vincent J.

2009-01-01

Background α-Hydroxy acids (αHA) are reported to reduce signs of aging in the skin and are widely used cosmetic ingredients. Several studies suggest that αHA can increase the sensitivity of skin to ultraviolet radiation. More recently, β-hydroxy acids (βHA), or combinations of αHA and βHA have also been incorporated into antiaging skin care products. Concerns have also arisen about increased sensitivity to ultraviolet radiation following use of skin care products containing β-HA. Objective To determine whether topical treatment with glycolic acid, a representative αHA, or with salicylic acid, a βHA, modifies the short-term effects of solar simulated radiation (SSR) in human skin. Methods Fourteen subjects participated in this study. Three of the four test sites on the mid-back of each subject were treated daily Monday - Friday, for a total of 3.5 weeks, with glycolic acid (10%), salicylic acid (2%), or vehicle (control). The fourth site received no treatment. After the last treatment, each site was exposed to SSR, and shave biopsies from all 4 sites were obtained. The endpoints evaluated in this study were erythema (assessed visually and instrumentally), DNA damage and sunburn cell formation. Results Treatment with glycolic acid resulted in increased sensitivity of human skin to SSR, measured as an increase in erythema, DNA damage and sunburn cell formation. Salicylic acid did not produce significant changes in any of these biomarkers. Conclusions Short-term topical application of glycolic acid in a cosmetic formulation increased the sensitivity of human skin to SSR, while a comparable treatment with salicylic acid did not. PMID:19411163

Antifreeze poisoning

MedlinePlus

The poisonous ingredients in antifreeze are: Ethylene glycol Methanol Propylene glycol ... For ethylene glycol: Death may occur within the first 24 hours. If the patient survives, there may be little ...

Determination of ochratoxin A in wine by means of immunoaffinity and aminopropyl solid-phase column cleanup and fluorometric detection.

PubMed

Longobardi, Francesco; Iacovelli, Vito; Catucci, Lucia; Panzarini, Giuseppe; Pascale, Michelangelo; Visconti, Angelo; Agostiano, Angela

2013-02-27

A new analytical method for the determination of ochratoxin A (OTA) in red wine has been developed by using a double-extract cleanup and a fluorometric measurement after spectral deconvolution. Wine samples were diluted with a solution containing 1% polyethylene glycol and 5% sodium hydrogencarbonate, filtered, and purified by immunoaffinity and aminopropyl solid-phase column. OTA contents in the purified extract were determined by a spectrofluorometer (excitation wavelength, 330 nm; emission wavelength, 470 nm) after deconvolution of fluorescence spectra. Average recoveries from wine samples spiked with OTA at levels ranging from 0.5 to 3.0 ng/mL were 94.5-105.4% with relative standard deviations (RSD) of <15% (n = 4). The limit of detection (LOD) was 0.2 ng/mL, and the total time of analysis was 30 min. The developed method was tested on 18 red wine samples (naturally contaminated and spiked with OTA at levels ranging from 0.4 to 3.0 ng/mL) and compared with AOAC Official Method 2001.01, based on immunoaffinity column cleanup and HPLC with fluorescence detector. A good correlation (r(2) = 0.9765) was observed between OTA levels obtained with the two methods, highlighting the reliability of the proposed method, the main advantage of which is the simple OTA determination by a benchtop fluorometer with evident reductions of cost and time of analysis.

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

40 CFR 63.63 - Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Deletion of ethylene glycol monobutyl... Quantity Designations, Source Category List § 63.63 Deletion of ethylene glycol monobutyl ether from the list of hazardous air pollutants. The substance ethylene glycol monobutyl ether (EGBE,2-Butoxyethanol...

End-group characterisation of poly(propylene glycol)s by means of electrospray ionisation-tandem mass spectrometry (ESI-MS/MS).

PubMed

Jackson, Anthony T; Slade, Susan E; Thalassinos, Konstantinos; Scrivens, James H

2008-10-01

The end-group functionalisation of a series of poly(propylene glycol)s has been characterised by means of electrospray ionisation-tandem mass spectrometry (ESI-MS/MS). A series of peaks with mass-to-charge ratios that are close to that of the precursor ion were used to generate information on the end-group functionalities of the poly(propylene glycol)s. Fragment ions resulting from losses of both of the end groups were noted from some of the samples. An example is presented of how software can be used to significantly reduce the length of time involved in data interpretation (which is typically the most time-consuming part of the analysis).

Anaerobic treatability of wastewater contaminated with propylene glycol.

PubMed

Sezgin, Naim; Tonuk, Gulseven Ubay

2013-09-01

The purpose of this study was to investigate the biodegradability of propylene glycol in anaerobic conditions by using methanogenic culture. A master reactor was set up to develop a culture that would be acclimated to propylene glycol. After reaching steady-state, culture was transferred to serum bottles. Three reactors with same initial conditions were run for consistency. Propylene glycol was completely biodegradable under anaerobic methanogenic conditions. Semi-continuous reactors operated at a temperature of 35°C had consistently achieved a propylene glycol removal of higher than 95 % based on chemical oxygen demand (COD). It was found that in semi-continuous reactors, anaerobic treatment of propylene glycol at concentrations higher than 1,500 mg COD m(-3) day(-1) was not convenient due to instable effluent COD.

Evaluation of Triethylene Glycol Monomethyl Ether (TRIEGME) as an Alternative Fuel System Icing Inhibitor for JP-8 Fuel

DTIC Science & Technology

2010-08-01

ALTERNATIVE FUEL SYSTEM ICING INHIBITOR FOR JP-8 FUEL 5a. CONTRACT NUMBER F33615-03-2-2347 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62203F...Government. The authors would like to acknowledge funding support from the DoD Reduction of Total Ownership Cost program through Ed Wells of ASC...following individuals contributed substantially to the success of this program : Rex Cash of the 540 ACSS/GFLBB, Travis Whitmer of Boeing IDS, Tedd Biddle of

Dynamic kinetic asymmetric cross-benzoin additions of β-stereogenic α-keto esters.

PubMed

Goodman, C Guy; Johnson, Jeffrey S

2014-10-22

The dynamic kinetic resolution of β-halo α-keto esters via an asymmetric cross-benzoin reaction is described. A chiral N-heterocyclic carbene catalyzes the umpolung addition of aldehydes to racemic α-keto esters. The resulting fully substituted β-halo glycolic ester products are obtained with high levels of enantio- and diastereocontrol. The high chemoselectivity observed is a result of greater electrophilicity of the α-keto ester toward the Breslow intermediate. The reaction products are shown to undergo highly diastereoselective substrate-controlled reduction to give highly functionalized stereotriads.

Dynamic Kinetic Asymmetric Cross-Benzoin Additions of β-Stereogenic α-Keto Esters

PubMed Central

2015-01-01

The dynamic kinetic resolution of β-halo α-keto esters via an asymmetric cross-benzoin reaction is described. A chiral N-heterocyclic carbene catalyzes the umpolung addition of aldehydes to racemic α-keto esters. The resulting fully substituted β-halo glycolic ester products are obtained with high levels of enantio- and diastereocontrol. The high chemoselectivity observed is a result of greater electrophilicity of the α-keto ester toward the Breslow intermediate. The reaction products are shown to undergo highly diastereoselective substrate-controlled reduction to give highly functionalized stereotriads. PMID:25299730

Microwave dielectric relaxation spectroscopy study of propylene glycol/ethanol binary mixtures: Temperature dependence

NASA Astrophysics Data System (ADS)

Vishwam, T.; Shihab, Suriya; Murthy, V. R. K.; Tiong, Ha Sie; Sreehari Sastry, S.

2017-05-01

Complex dielectric permittivity measurements of propylene glycol (PG) in ethanol at various mole fractions were measured by using open-ended coaxial probe technique at different temperatures in the frequency range 0.02 < ν/GHz < 20. The dipole moment (μ), excess dipole moment (Δμ),excess permittivity (εE), excess inverse relaxation time(1/τ)E, Bruggeman parameter (fB), excess Helmholtz energy (ΔFE) are determined using experimental data. From the minimum energy based geometry optimization, dipole moments of individual monomers of propylene glycol and ethanol and their binary system have been evaluated theoretically at gaseous state as well as alcoholic medium by using PCM and IEFPCM solvation models from the Hatree-Fock (HF) and Density Functional Theory (DFT-B3LYP) methods with 6-311G* and 6-311G** basis sets. The obtained results have been interpreted in terms of the short and long range ordering of the dipoles, Kirkwood correlation factor (geff), thermodynamic parameters, mean molecular polarizability (αM) and interaction in the mixture through hydrogen bonding. Dielectric relaxation study of propylene glycol in ethanol medium Determination of excess dielectric and thermodynamic parameters Comparison of experimental dipole moment with theoretical calculations Interpretation of the molecular interactions in the liquid through H-bonding Correlation between the evaluated dielectric parameters and theoretical results

A novel strategy for the preparation of porous microspheres and its application in peptide drug loading.

PubMed

Wei, Yi; Wang, Yuxia; Zhang, Huixia; Zhou, Weiqing; Ma, Guanghui

2016-09-15

A new strategy is developed to prepare porous microspheres with narrow size distribution for peptides controlled release, involving a fabrication of porous microspheres without any porogens followed by a pore closing process. Amphiphilic polymers with different hydrophobic segments (poly(monomethoxypolyethylene glycol-co-d,l-lactide) (mPEG-PLA), poly(monomethoxypolyethylene glycol-co-d,l-lactic-co-glycolic acid) (mPEG-PLGA)) are employed as microspheres matrix to prepare porous microspheres based on a double emulsion-premix membrane emulsification technique combined with a solvent evaporation method. Both microspheres possess narrow size distribution and porous surface, which are mainly caused by (a) hydrophilic polyethylene glycol (PEG) segments absorbing water molecules followed by a water evaporation process and (b) local explosion of microspheres due to fast evaporation of dichloromethane (MC). Importantly, mPEG-PLGA microspheres have a honeycomb like structure while mPEG-PLA microspheres have a solid structure internally, illustrating that the different hydrophobic segments could modulate the affinity between solvent and matrix polymer and influence the phase separation rate of microspheres matrix. Long term release patterns are demonstrated with pore-closed microspheres, which are prepared from mPEG-PLGA microspheres loading salmon calcitonin (SCT). These results suggest that it is potential to construct porous microspheres for drug sustained release using permanent geometric templates as new porogens. Copyright © 2016 Elsevier Inc. All rights reserved.

Method for purifying bidentate organophosphorus compounds

DOEpatents

Schulz, Wallace W.

1977-01-01

Bidentate organophosphorus compounds useful for extracting actinide elements from acidic nuclear waste solutions are purified of undesirable acidic impurities by contacting the compounds with ethylene glycol which preferentially extracts the impurities found in technical grade bidentate compounds.

Polyethylene glycol 3350 in occasional constipation: A one-week, randomized, placebo-controlled, double-blind trial

PubMed Central

McGraw, Thomas

2016-01-01

AIM: To evaluate the efficacy and safety of polyethylene glycol (PEG) 3350 in subjects with self-reported occasional constipation. METHODS: Eligible subjects ≥ 17 years of age were randomized to receive either placebo or PEG 3350 17 g once daily in this multicenter, double-blind trial. Evaluations were conducted before (baseline) and after a 7-d treatment period. The primary efficacy variable was the proportion of subjects reporting complete resolution of straining and hard or lumpy stools. Secondary efficacy variables assessed the severity of the subjects’ daily bowel movement (BM) symptoms, and preference of laxatives based on diary entries, visual analog scale scores, and questionnaires. RESULTS: Of the 203 subjects enrolled in the study, 11 had major protocol violations. Complete resolution was noted by 36/98 (36.7%) subjects in the PEG 3350 group and 23/94 (24.5%) in the placebo group (P = 0.0595). The number of complete BMs without straining or lumpy stools was similar between both groups. Subjects receiving PEG 3350 experienced significant relief in straining and reduction in hardness of stools over a 7-d period (P < 0.0001). Subjects reported that PEG 3350 had a better effect on their daily lives, provided better control over a BM, better relief from constipation, cramping, and bloating, and was their preferred laxative. Adverse events (AEs) were balanced between the PEG 3350 and the placebo groups. No deaths, serious AEs, or discontinuations due to AEs were reported. This trial is registered at clinicaltrials.gov as NCT00770432. CONCLUSION: Oral administration of 17 g PEG 3350 once daily for a week is effective, safe, and well tolerated in subjects with occasional constipation. PMID:27158544

PVA and PEG functionalised LSMO nanoparticles for magnetic fluid hyperthermia application

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

Jadhav, S.V.; Nikam, D.S.; Khot, V.M.

2015-04-15

La{sub 0.7}Sr{sub 0.3}MnO{sub 3} magnetic nanoparticles are synthesized by a solution combustion method and functionalised with polyvinyl alcohol and polyethylene glycol. The induction heating characteristics of coated magnetic nanoparticles (42 °C) were observed at a reasonably low concentration (5 mg/mL). Remarkably, coated magnetic nanoparticles exhibited a promisingly high specific absorption rate with varying magnetic field and constant frequency. The surface analysis is carried out by X-ray photoelectron spectroscopy. A reduction in the agglomeration of the particles was observed when the magnetic nanoparticles were functionalised with polyvinyl alcohol or polyethylene glycol and can be confirmed by transmission electron microscopy and dynamicmore » light scattering studies. Vibrating sample magnetometer measurements indicate superparamagnetic behaviour at room temperature before and after coating. Colloidal stability revealed a considerably higher zeta potential value for coated system. In vitro cytotoxicity test of the magnetic nanoparticles indicates that coated nanoparticles have no significant effect on cell viability within the tested concentrations (1–5 mg mL{sup -1}) as compared to uncoated La{sub 0.7}Sr{sub 0.3}MnO{sub 3}. All these findings explore the potentiality of La{sub 0.7}Sr{sub 0.3}MnO{sub 3} nanoparticles for magnetic fluid hyperthermia. - Highlights: • Surface functionalization of LSMO nanoparticles — first time with PVA • Surface functionalization of LSMO nanoparticles — first time with PEG • BSA protein — first time used as dispersion medium for stability of LSMO nanoparticles • The heating ability observed at low concentration • Improved efficiency of magnetic fluid hyperthermia treatment with surfactants.« less

Antitumor activity of monomethoxy poly(ethylene glycol)-poly (ε-caprolactone) micelle-encapsulated doxorubicin against mouse melanoma.

PubMed

Zheng, Lan; Gou, Maling; Zhou, Shengtao; Yi, Tao; Zhong, Qian; Li, Zhengyu; He, Xiang; Chen, Xiancheng; Zhou, Lina; Wei, Yuquan; Qian, Zhiyong; Zhao, Xia

2011-06-01

Doxorubicin (Dox) is one of the most commonly used and highly effective antineoplastic agents, but the clinical application of this broad spectrum drug is largely hampered by its poor stability and serious toxicity to normal tissues. Hence, it is essential to improve the therapeutic effect and decrease the systematic toxicity for the administration of doxorubicin. In our study, doxorubicin was incorporated into monomethoxy poly(ethylene glycol)-poly(ε-caprolactone) (MPEG-PCL) micelle by a self-assembly method. The cytotoxicity and cellular uptake efficiency of Dox-loaded MPEG-PCL (Dox/MPEG-PCL) micelle against B16-F10 murine melanoma cells was examined by the methylthiazoltetrazolium (MTT) test and flow cytometry. The antitumor activity of Dox/MPEG-PCL was evaluated in C57BL/6 mice injected subcutaneously with B16-F10 cells. Toxicity was evaluated in tumor-free mice. Meanwhile, tumor proliferation, intratumoal angiogenesis and apoptotic cells were evaluated by PCNA, CD31 staining and TUNEL assay, respectively. Encapsulation of doxorubicin in MPEG-PCL micelle improved the cytotoxicity of doxorubicin and enhanced its cellular uptake on B16-F10 cell in vitro. Administration of Dox/MPEG-PCL micelle resulted in significant inhibition (75% maximum inhibition relative to controls) in the growth of B16-F10 tumor xenografts and prolonged the survival of the treated mice (P<0.05). These anti-tumor responses were associated with marked increase of tumor apoptosis and notable reduction of cell proliferation and intratumoral microvessel density (P<0.05). The system toxicity also decreased in the Dox/MPEG-PCL group compared with free doxorubicin group. Our data indicate that the encapsulation of doxorubicin in MPEG-PCL micelle improved the anti-tumor activity in vivo without conspicuous systemic toxic effects.

In vitro antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis in root canals.

PubMed

Valera, Marcia Carneiro; Maekawa, Lilian Eiko; de Oliveira, Luciane Dias; Jorge, Antonio Olavo Cardoso; Shygei, Érika; Carvalho, Cláudio Antonio Talge

2013-01-01

The aim of this study was to evaluate the antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis inoculated in root canals. Seventy-two human tooth roots were contaminated with C. albicans and E. faecalis for 21 days. The groups were divided according to the auxiliary chemical substance into: G1) 2.5% sodium hypochlorite (NaOCl), G2) 2% chlorhexidine gel (CHX), G3) castor oil, G4) glycolic Aloe vera extract, G5) glycolic ginger extract, and G6) sterile saline (control). The samples of the root canal were collected at different intervals: confirmation collection, at 21 days after contamination; 1st collection, after instrumentation; and 2nd collection, seven days after instrumentation. Microbiological samples were grown in culture medium and incubated at 37°C for 48 hours. The results were submitted to the Kruskal-Wallis and Dunn (5%) statistical tests. NaOCl and CHX completely eliminated the microorganisms of the root canals. Castor oil and ginger significantly reduced the number of CFU of the tested bacteria. Reduction of CFU/mL at the 1st and 2nd collections for groups G1, G2, G3 and G4 was greater in comparison to groups G5 and G6. It was concluded that 2.5% sodium hypochlorite and 2% chlorhexidine gel were more effective in eliminating C. albicans and E. faecalis, followed by the castor oil and glycolic ginger extract. The Aloe vera extract showed no antimicrobial activity.

Inducible antisense suppression of glycolate oxidase reveals its strong regulation over photosynthesis in rice.

PubMed

Xu, Huawei; Zhang, Jianjun; Zeng, Jiwu; Jiang, Linrong; Liu, Ee; Peng, Changlian; He, Zhenghui; Peng, Xinxiang

2009-01-01

Photorespiration is one of the most intensively studied topics in plant biology. While a number of mutants deficient in photorespiratory enzymes have been identified and characterized for their physiological functions, efforts on glycolate oxidase (GLO; EC 1.1.3.15) have not been so successful. This is a report about the generation of transgenic rice (Oryza sativa L.) plants carrying a GLO antisense gene driven by an estradiol-inducible promoter, which allowed for controllable suppressions of GLO and its detailed functional analyses. The GLO-suppressed plants showed typical photorespiration-deficient phenotypes. More intriguingly, it was found that a positive and linear correlation existed between GLO activities and the net photosynthetic rates (P(N)), and photoinhibition subsequently occurred once P(N) reduction surpassed 60%, indicating GLO can exert a strong regulation over photosynthesis. Various expression analyses identified that Rubisco activase was transcriptionally suppressed in the GLO-suppressed plants, consistent with the decreased Rubisco activation states. While the substrate glycolate accumulated substantially, few changes were observed for the product glyoxylate, and for some other downstream metabolites or genes as well in the transgenic plants. Further analyses revealed that isocitrate lyase and malate synthase, two key enzymes in the glyoxylate cycle, were highly up-regulated under GLO deficiency. Taken together, the results suggest that GLO is a typical photorespiratory enzyme and that it can exert a strong regulation over photosynthesis, possibly through a feed-back inhibition on Rubisco activase, and that the glyoxylate cycle may be partially activated to compensate for the photorespiratory glyoxylate when GLO is suppressed in rice.

21 CFR 500.50 - Propylene glycol in or on cat food.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Propylene glycol in or on cat food. 500.50 Section... Propylene glycol in or on cat food. The Food and Drug Administration has determined that propylene glycol in or on cat food is not generally recognized as safe and is a food additive subject to section 409 of...

21 CFR 589.1001 - Propylene glycol in or on cat food.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Propylene glycol in or on cat food. 589.1001... Listing of Specific Substances Prohibited From Use in Animal Food or Feed § 589.1001 Propylene glycol in or on cat food. The Food and Drug Administration has determined that propylene glycol in or on cat...

21 CFR 589.1001 - Propylene glycol in or on cat food.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Propylene glycol in or on cat food. 589.1001... Listing of Specific Substances Prohibited From Use in Animal Food or Feed § 589.1001 Propylene glycol in or on cat food. The Food and Drug Administration has determined that propylene glycol in or on cat...

21 CFR 589.1001 - Propylene glycol in or on cat food.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Propylene glycol in or on cat food. 589.1001... Listing of Specific Substances Prohibited From Use in Animal Food or Feed § 589.1001 Propylene glycol in or on cat food. The Food and Drug Administration has determined that propylene glycol in or on cat...

21 CFR 172.856 - Propylene glycol mono- and diesters of fats and fatty acids.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Propylene glycol mono- and diesters of fats and... CONSUMPTION Multipurpose Additives § 172.856 Propylene glycol mono- and diesters of fats and fatty acids. Propylene glycol mono- and diesters of fats and fatty acids may be safely used in food, subject to the...

21 CFR 500.50 - Propylene glycol in or on cat food.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Propylene glycol in or on cat food. 500.50 Section... Propylene glycol in or on cat food. The Food and Drug Administration has determined that propylene glycol in or on cat food is not generally recognized as safe and is a food additive subject to section 409 of...

Scalable synthesis of palladium icosahedra in plug reactors for the production of oxygen reduction reaction catalysts

DOE PAGES

Wang, Helan; Niu, Guangda; Zhou, Ming; ...

2016-03-10

We have synthesized Pd icosahedra with uniform, controllable sizes in plug reactors separated by air. The oxygen contained in the air segments not only contributed to the generation of a reductant from diethylene glycol in situ, but also oxidized elemental Pd back to the ionic form by oxidative etching and thus slowed down the reduction kinetics. Compared to droplet reactors involving silicone oil or fluorocarbon, the use of air as a carrier phase could reduce the production cost by avoiding additional procedures for the separation of products from the oil. The average diameters of the Pd icosahedra could be readilymore » controlled in the range of 12–20 nm. The Pd icosahedra were further employed as seeds for the production of Pd@Pt 2–3L core-shell icosahedra, which could serve as a catalyst toward the oxygen reduction reaction with greatly enhanced activity. As a result, we believe that the plug reactors could be extended to other types of noble-metal nanocrystals for their scale-up production.« less

Biodegradation of Ethylene Glycol by a Salt-Requiring Bacterium1

PubMed Central

Gonzalez, Carlos F.; Taber, Willard A.; Zeitoun, M. A.

1972-01-01

A gram-negative nonmotile rod which was capable of using 1,2-14C-ethylene glycol as a sole carbon source for growth was isolated from a brine pond, Great Salt Lake, Utah. The bacterium (ATCC 27042) required at least 0.85% NaCl for growth and, although the chloride ion was replaceable by sulfate ion, the sodium ion was not replaceable by potassium ion. The maximal concentration of salt tolerated for growth was approximately 12%. The bacterium was oxidase-negative when N,N-dimethyl-p-phenylenediamine was used and weakly positive when N,N,N′,N′-tetramethyl-p-phenylenediamine was used. It grows on many sugars but does not ferment them, it does not have an exogenous vitamin requirement, and it possesses a guanine plus cytosine ratio of 64.3%. Incorporation of ethylene glycol carbon into cell and respired CO2 was quantitated by use of radioactive ethylene glycol and a force-aerated fermentor. Glucose suppressed ethylene glycol metabolism. Cells grown on ethylene and propylene glycol respired ethylene glycol in a Warburg respirometer more rapidly than cells grown on glucose. Spectrophotometric evidence was obtained for oxidation of glycolate to glyoxylate by a dialyzed cell extract. PMID:4568254

Glycolic acid physical properties and impurities assessment

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

Lambert, D. P.; Pickenheim, B. R.; Hay, M. S.

This document has been revised to add analytical data for fresh, 1 year old, and 4 year old glycolic acid as recommended in Revision 2 of this document. This was needed to understand the concentration of formaldehyde and methoxyacetic acid, impurities present in the glycolic acid used in Savannah River National Laboratory (SRNL) experiments. Based on this information, the concentration of these impurities did not change during storage. These impurities were in the glycolic acid used in the testing included in this report and in subsequent testing using DuPont (now called Chemours) supplied Technical Grade 70 wt% glycolic acid. However,more » these impurities were not reported in the first two versions of this report. The Defense Waste Processing Facility (DWPF) is planning to implement a nitric-glycolic acid flowsheets to increase attainment to meet closure commitment dates during Sludge Batch 9. In fiscal year 2009, SRNL was requested to determine the physical properties of formic and glycolic acid blends.« less

FERMENTATION OF ETHYLENE GLYCOL BY CLOSTRIDIUM GLYCOLICUM, SP. N1

PubMed Central

Gaston, Lamont W.; Stadtman, E. R.

1963-01-01

Gaston, Lamont W. (National Heart Institute, National Institutes of Health, Bethesda, Md.) and E. R. Stadtman. Fermentation of ethylene glycol by Clostridium glycolicum, sp. n. J. Bacteriol. 85:356–362. 1963.—An anaerobic organism which utilizes ethylene glycol as a source of energy and carbon has been isolated from mud. It is a long (5 μ), slender, motile, gram-positive, spore-forming rod, with peritrichous flagellae. It grows well from 22 to 37 C at pH 7.4 to 7.6, and ferments glucose, fructose, sorbitol, dulcitol, and cellulose. It does not reduce nitrates, form indole, or cause hemolysis or proteolysis except for a slight attack on coagulated egg albumin. Fifteen amino acids and the vitamins biotin and pantothenate are required for optimal growth on ethylene glycol. Analogues other than propylene glycol do not support growth. Ethylene glycol and propylene glycol are stoichiometrically converted to equal amounts of the respective acid and alcohol. PMID:13946772

Mono-Amine Functionalized Phthalocyanines: Mwave-Assisted Solid-Phase Synthesis and Bioconjugation Strategies

PubMed Central

Erdem, S. Sibel; Nesterova, Irina V.; Soper, Steven A.; Hammer, Robert P.

2009-01-01

Phthalocyanines (Pcs) are excellent candidates for use as fluors for near-infrared (near-IR) fluorescent tagging of biomolecules for a wide variety of bioanalytical applications. Mono-functionalized Pcs, having two different types of peripheral substitutents; one for covalent conjugation of the Pc to biomolecules and others to improve the solubility of the macrocycle, ideally suit for the desired applications. To date, difficulties faced during the purification of the mono-functionalized Pcs limited their usage in various types of applications. Herein are reported a new synthetic method for rapid synthesis of the target Pcs and bioconjugation techniques for labeling of the oligonucleotides with the near-IR flours. A novel synthetic route was developed utilizing a hydrophilic, polyethylene glycol-based (PEG) support with an acid labile Rink Amide linker. The Pcs were functionalized with an amine group for covalent conjugation purposes and were decorated with short PEG chains, serving as solubilizing groups. Mwave-assisted solid-phase synthetic method was successfully applied to obtain pure asymmetrically-substituted mono-amine functionalized Pcs in a short period of time. Three different bioconjugation techniques, reductive amination, amidation and Huisgen cycloaddition, were employed for covalent conjugation of Pcs to oligonucleotides. The described μwave-assisted bioconjugation methods give an opportunity to synthesize and isolate the Pc-oligonucleotide conjugate in a few hours. PMID:19911767

Glass transition behavior of ternary disaccharide-ethylene glycol-water solutions

NASA Astrophysics Data System (ADS)

Yu, Tongxu; Zhao, Lishan; Wang, Qiang; Cao, Zexian

2017-06-01

Glass transition behavior of ternary disaccharide-ethylene glycol-water solutions, in reference to that of the binary combinations, has been investigated towards a better understanding of their cryoprotective ability. In water-deficient solutions, the disaccharides, including trehalose, sucrose and maltose, can associate with more than 100 ethylene glycol molecules to form amorphous complex, one order of magnitude larger than the corresponding hydration numbers. In water-rich solutions, a second glass transition emerges with increasing molar fraction of ethylene glycol, indicating the possible synergy of disaccharides and ethylene glycol in vitrification of the ternary aqueous solution.

Environmental Aspects of Aircraft and Airfield Deicing - An Air Force Perspective

DTIC Science & Technology

2010-11-01

e l l e n c e COD of Aircraft Deicers ADF Kg O2/Kg compd Ethylene glycol 1.14 T Propylene glycol 1.47 T Isopropyl alcohol 2.11 T Neopentyl glycol ...showed that commercial airports use about 25 million gallons of Aircraft Deicing Fluid (ADF) annually, of which 22.1 M (88%) is Propylene Glycol (PG...S e r v i c e - E x c e l l e n c e AF Aircraft Deicing Overview 70% (107) of bases reported using aircraft deicers Propylene Glycol (PG), AMS 1424

An approach to the systematic analysis of urinary steroids

PubMed Central

Menini, E.; Norymberski, J. K.

1965-01-01

1. Human urine, its extracts, extracts of urine pretreated with enzyme preparations containing β-glucuronidase and steroid sulphatase or β-glucuronidase alone, and products derived from the specific solvolysis of urinary steroid sulphates, were submitted to the following sequence of operations: reduction with borohydride; oxidation with a glycol-cleaving agent (bismuthate or periodate); separation of the products into ketones and others; oxidation of each fraction with tert.-butyl chromate, resolution of the end products by means of paper chromatography or gas–liquid chromatography or both. 2. Qualitative experiments indicated the kind of information the method and some of its modifications can provide. Quantitative experiments were restricted to the direct treatment of urine by the basic procedure outlined. It was partly shown and partly argued that the quantitative results were probably as informative about the composition of the major neutral urinary steroids (and certainly about their presumptive secretory precursors) as those obtained by a number of established analytical procedures. 3. A possible extension of the scope of the reported method was indicated. 4. A simple technique was introduced for the quantitative deposition of a solid sample on to a gas–liquid-chromatographic column. PMID:14333557

The synthesis and characterization of biotin-silver-dendrimer nanocomposites as novel bioselective labels

NASA Astrophysics Data System (ADS)

Malý, J.; Lampová, H.; Semerádtová, A.; Štofik, M.; Kováčik, L.

2009-09-01

This paper presents a synthesis of a novel nanoparticle label with selective biorecognition properties based on a biotinylated silver-dendrimer nanocomposite (AgDNC). Two types of labels, a biotin-AgDNC (bio-AgDNC) and a biotinylated AgDNC with a poly(ethylene)glycol spacer (bio-PEG-AgDNC), were synthesized from a generation 7 (G7) hydroxyl-terminated ethylenediamine-core-type (2-carbon core) PAMAM dendrimer (DDM) by an N,N'-dicyclohexylcarbodiimide (DDC) biotin coupling and a NaBH4 silver reduction method. Synthesized conjugates were characterized by several analytical methods, such as UV-vis, FTIR, AFM, TEM, ELISA, HABA assay and SPR. The results show that stable biotinylated nanocomposites can be formed either with internalized silver nanoparticles (AgNPs) in a DMM polymer backbone ('type I') or as externally protected ('type E'), depending on the molar ratio of the silver/DMM conjugate and type of conjugate. Furthermore, the selective biorecognition function of the biotin is not affected by the AgNPs' synthesis step, which allows a potential application of silver nanocomposite conjugates as biospecific labels in various bioanalytical assays, or potentially as fluorescence cell biomarkers. An exploitation of the presented label in the development of electrochemical immunosensors is anticipated.

Plasma-deposited tetraglyme surfaces greatly reduce total blood protein adsorption, contact activation, platelet adhesion, platelet procoagulant activity, and in vitro thrombus deposition.

PubMed

Cao, Lan; Chang, Mark; Lee, Chi-Ying; Castner, David G; Sukavaneshvar, Sivaprasad; Ratner, Buddy D; Horbett, Thomas A

2007-06-15

The ability of tetraethylene glycol dimethyl ether (tetraglyme) plasma deposited coatings exhibiting ultralow fibrinogen adsorption to reduce blood activation was studied with six in vitro methods, namely fibrinogen and von Willebrand's factor adsorption, total protein adsorption, clotting time in recalcified plasma, platelet adhesion and procoagulant activity, and whole blood thrombosis in a disturbed flow catheter model. Surface plasmon resonance results showed that tetraglyme surfaces strongly resisted the adsorption of all proteins from human plasma. The clotting time in the presence of tetraglyme surfaces was lengthened compared with controls, indicating a lower activation of the intrinsic coagulation cascade. Platelet adhesion and thrombin generation by adherent platelets were greatly reduced on tetraglyme-coated materials, compared with uncoated and Biospan-coated glass slides. In the in vitro disturbed blood flow model, tetraglyme plasma coated catheters had 50% less thrombus than did the uncoated catheters. Tetraglyme-coated materials thus had greatly reduced blood interactions as measured with all six methods. The improved blood compatibility of plasma-deposited tetraglyme is thus not only due to their reduced platelet adhesion and activation, but also to a generalized reduction in blood interactions. (c) 2007 Wiley Periodicals, Inc.

Linear and crosslinked Polyurethanes based catalysts for reduction of methylene blue.

PubMed

Sultan, Misbah; Javeed, Asma; Uroos, Maliha; Imran, Muhammad; Jubeen, Farhat; Nouren, Shazia; Saleem, Nazish; Bibi, Ismat; Masood, Rashid; Ahmed, Waqas

2018-02-15

The large amount of synthetic dyes in effluents is a serious concern to be addressed. The chemical reduction is one of the potential way to resolve this problem. In this study, linear and crosslinked polyurethanes i.e. LPUR & CLPUR were synthesized from toluene diisocyanate (TDI), polyethylene glycol (PEG;1000g/mole) and tetraethylenepentamine (TEPA). The structure and morphology of synthesized materials were examined by FTIR, SEM and BET. The CLPUR was found stable in aqueous system with 0.80g/cm 3 density and 16.4998m 2 g -1 surface area. These materials were applied for the reduction of methylene blue in presence of NaBH 4 . Both, polymers catalyzed the process and showed 100% reduction in 16 and 28mins., respectively, while, the reduction rate was significantly low in absence of these materials, even after 120mins. Furthermore, negligible adsorption was observed with only 7% removal of dye. The best reduction rates were observed at low concentration of dye, increasing concentration of NaBH 4 and with more dosage of polymeric catalyst. The kinetic study of process followed zero order kinetics. It was hence concluded that both synthesized polymers played a catalytic role in reduction process. However, stability in aqueous system and better efficiency in reduction process endorsed CLPUR as an optimal choice for further studies. Copyright © 2017 Elsevier B.V. All rights reserved.

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.

Equine ovarian tissue viability after cryopreservation and in vitro culture

USDA-ARS?s Scientific Manuscript database

The efficiency of several cryoprotective agents were compared using both slow-freezing and vitrification methods. Results indicate that the viability of ovarian tissue cells increases when DMSO (slow-freezing) and ethylene glycol (vitrification) are used....

Enantioselective synthesis of L-(-)-4- boronophenylalanine (L-BPA)

DOEpatents

Samsel, Edward G.

1992-01-01

A method of making substantially pure L-BPA is disclosed. The method includes the steps of reacting 4-bromobenzaldehyde with ethylene glycol to form 4-bromobenzaldehyde ethylene glycol acetal, sequentially reacting 4-bromobenzaldehyde ethyleneglycol acetal with Mg to produce the Grignard reagent and thereafter reacting with tributyl borate and then converting to an acid environment to form 4-boronobenzaldehyde, reacting 4-boronobenzaldehyde with diethanol amine to form 4-boronobenzaldehyde diethanolamine ester, condensing the 4-boronobenzaldehyde diethanolamine ester with 2-phenyl-2-oxazolin-5-one to form an azlactone, reacting the azlactone with an alkali metal hydroxide to form z-.alpha.-benzoylamino-4-boronocinnamic acid, asymmetrically hydrogenating the z-.alpha.-benzoylamino-4-boronocinnamic acid in the presence of a catalyst of a cheltate complex of rhodium (I) with chiral bisphosphines to form L-(+)-N-benzoyl-4-boronophenylalanine, and thereafter acidifying the L-(+)-N-benzoyl-4-boronophenylalanine in an organic medium to produce L-BPA.

Enantioselective synthesis of L-(-)-4- boronophenylalanine (L-BPA)

DOEpatents

Samsel, E.G.

1992-10-20

A method of making substantially pure L-BPA is disclosed. The method includes the steps of reacting 4-bromobenzaldehyde with ethylene glycol to form 4-bromobenzaldehyde ethylene glycol acetal, sequentially reacting 4-bromobenzaldehyde ethyleneglycol acetal with Mg to produce the Grignard reagent and thereafter reacting with tributyl borate and then converting to an acid environment to form 4-boronobenzaldehyde, reacting 4-boronobenzaldehyde with diethanol amine to form 4-boronobenzaldehyde diethanolamine ester, condensing the 4-boronobenzaldehyde diethanolamine ester with 2-phenyl-2-oxazolin-5-one to form an azlactone, reacting the azlactone with an alkali metal hydroxide to form z-[alpha]-benzoylamino-4boronocinnamic acid, asymmetrically hydrogenating the z-[alpha]-benzoylamino-4-boronocinnamic acid in the presence of a catalyst of a cheltate complex of rhodium (I) with chiral bisphosphines to form L-(+)-N-benzoyl-4-boronophenylalanine, and thereafter acidifying the L-(+)-N-benzoyl-4-boronophenylalanine in an organic medium to produce L-BPA. 3 figs.

Investigation on hemolytic effect of poly(lactic co-glycolic) acid nanoparticles synthesized using continuous flow and batch processes

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

Libi, Sumit; Calenic, Bogdan; Astete, Carlos E.

Abstract With the increasing interest in polymeric nanoparticles for biomedical applications, there is a need for continuous flow methodologies that allow for the precise control of nanoparticle synthesis. Poly(lactide-co-glycolic) acid (PLGA) nanoparticles with diameters of 220–250 nm were synthesized using a lab-on-a-chip, exploiting the precise flow control offered by a millifluidic platform. The association and the effect of PLGA nanoparticles on red blood cells (RBCs) were compared for fluorescent PLGA nanoparticles made by this novel continuous flow process using a millifluidic chip and smaller PLGA nanoparticles made by a batch method. Results indicated that all PLGA nanoparticles studied, independent ofmore » the synthesis method and size, adhered to the surface of RBCs but had no significant hemolytic effect at concentrations lower than 10 mg/ml.« less

Preparation, co-assembling and interfacial crosslinking of photocurable and folate-conjugated amphiphilic block copolymers for controlled and targeted drug delivery: smart armored nanocarriers.

PubMed

Khoee, Sepideh; Kavand, Alireza

2014-02-12

Novel pH-sensitive, biodegradable and biocompatible copolymers based on polycaprolactone-poly(ethylene glycol) (PCL/PEG) were synthesized and further modified with folic acid and/or acryloyl chloride. The mixed polymeric micelles were formed by self-assembling of folated-copolymer and non-folated-copolymer with different compositions via nanoprecipitation method. The solubilization of quercetin as anti-cancer drug by the mixed micelle with the optimized composition (folated/non-folated 20/80) was more efficient than those made of each one alone. Nanogels with different crosslinking density were produced in the presence of ethylene glycol dimethacrylate (EGDMA) as the crosslinker via a photochemical method. Interfacial crosslinking of acrylated groups were utilized to produce a core-shell spherical nanoparticle to evaluate their in-vitro drug release and degradation rate. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

75 FR 53867 - Additions to Listing of Exempt Chemical Mixtures

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-02

...% acetonitrile), dimethylformamide, ethylene glycol, isopropanol, methanol, methanol/water (50:50), methanol..., acetonitrile, acetonitrile: water (>= 50% acetonitrile), dimethylformamide, ethylene glycol, isopropanol...% acetonitrile), dimethylformamide, ethylene glycol, isopropanol, methanol, methanol/water (50:50), methanol...

[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.

Status Epilepticus due to Intraperitoneal Injection of Vehicle Containing Propylene Glycol in Sprague Dawley Rats

PubMed Central

Meade, Seth M.; Smith, Cara S.; Chen, Keying; Kleinman, Nanette; Capadona, Jeffrey R.

2017-01-01

Published reports of status epilepticus due to intraperitoneal injection containing propylene glycol in rats are sparse. In fact, there are no reports specifying a maximum safe dose of propylene glycol through intraperitoneal administration. We report here a case of unexpected seizures in Sprague Dawley rats after receiving an intraperitoneal injection containing propylene glycol. Nine-week-old, 225–250 gram male rats were reported to experience tremor progressing to seizures within minutes after given injections of resveratrol (30 mg/kg) dissolved in a 40 : 60 propylene glycol/corn oil vehicle solution by direct intraperitoneal (IP) slow bolus injection or via a preplaced intraperitoneal catheter. The World Health Organization suggests a maximum dose of 25 mg/kg/day of propylene glycol taken orally and no more than 25 mg/dL in blood serum, whereas the animals used in our study got a calculated maximum 0.52 g/kg (25 times lower dose). Blood tests from the seizing rat support a diagnosis of hemolysis and lactic acidosis which may have led to the seizures, all of which appeared to be a consequence of the propylene glycol administration. These findings are consistent with oral and intravenous administration of propylene glycol toxicity as previously reported in other species, including humans. To our knowledge, this report represents the first published case of status epilepticus due to an IP injection containing propylene glycol. PMID:28785508

Stabilization of distearoylphosphatidylcholine lamellar phases in propylene glycol using cholesterol.

PubMed

Harvey, Richard D; Ara, Nargis; Heenan, Richard K; Barlow, David J; Quinn, Peter J; Lawrence, M Jayne

2013-12-02

Phospholipid vesicles (liposomes) formed in pharmaceutically acceptable nonaqueous polar solvents such as propylene glycol are of interest in drug delivery because of their ability to improve the bioavailability of drugs with poor aqueous solubility. We have demonstrated a stabilizing effect of cholesterol on lamellar phases formed by dispersion of distearoylphosphatidylcholine (DSPC) in water/propylene glycol (PG) solutions with glycol concentrations ranging from 0 to 100%. The stability of the dispersions was assessed by determining the effect of propylene glycol concentration on structural parameters of the lamellar phases using a complementary combination of X-ray and neutron scattering techniques at 25 °C and in the case of X-ray scattering at 65 °C. Significantly, although stable lamellar phases (and liposomes) were formed in all PG solutions at 25 °C, the association of the glycol with the liposomes' lamellar structures led to the formation of interdigitated phases, which were not thermostable at 65 °C. With the addition of equimolar quantities of cholesterol to the dispersions of DSPC, stable lamellar dispersions (and indeed liposomes) were formed in all propylene glycol solutions at 25 °C, with the significant lateral phase separation of the bilayer components only detectable in propylene glycol concentrations above 60% (w/w). We propose that the stability of lamellar phases of the cholesterol-containing liposomes formed in propylene glycol concentrations of up to 60% (w/w) represent potentially very valuable drug delivery vehicles for a variety of routes of administration.

Status Epilepticus due to Intraperitoneal Injection of Vehicle Containing Propylene Glycol in Sprague Dawley Rats.

PubMed

Ereifej, Evon S; Meade, Seth M; Smith, Cara S; Chen, Keying; Kleinman, Nanette; Capadona, Jeffrey R

2017-01-01

Published reports of status epilepticus due to intraperitoneal injection containing propylene glycol in rats are sparse. In fact, there are no reports specifying a maximum safe dose of propylene glycol through intraperitoneal administration. We report here a case of unexpected seizures in Sprague Dawley rats after receiving an intraperitoneal injection containing propylene glycol. Nine-week-old, 225-250 gram male rats were reported to experience tremor progressing to seizures within minutes after given injections of resveratrol (30 mg/kg) dissolved in a 40 : 60 propylene glycol/corn oil vehicle solution by direct intraperitoneal (IP) slow bolus injection or via a preplaced intraperitoneal catheter. The World Health Organization suggests a maximum dose of 25 mg/kg/day of propylene glycol taken orally and no more than 25 mg/dL in blood serum, whereas the animals used in our study got a calculated maximum 0.52 g/kg (25 times lower dose). Blood tests from the seizing rat support a diagnosis of hemolysis and lactic acidosis which may have led to the seizures, all of which appeared to be a consequence of the propylene glycol administration. These findings are consistent with oral and intravenous administration of propylene glycol toxicity as previously reported in other species, including humans. To our knowledge, this report represents the first published case of status epilepticus due to an IP injection containing propylene glycol.

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.

Reduction-Degradable Polymeric Micelles Decorated with PArg for Improving Anticancer Drug Delivery Efficacy.

PubMed

Cui, Yani; Sui, Junhui; He, Mengmeng; Xu, Zhiyi; Sun, Yong; Liang, Jie; Fan, Yujiang; Zhang, Xingdong

2016-01-27

In this study, five kinds of reduction-degradable polyamide amine-g-polyethylene glycol/polyarginine (PAA-g-PEG/PArg) micelles with different proportions of hydrophilic and hydrophobic segments were synthesized as novel drug delivery vehicles. Polyarginine not only acted as a hydrophilic segment but also possessed a cell-penetrating function to carry out a rapid transduction into target cells. Polyamide amine-g-polyethylene glycol (PAA-g-PEG) was prepared for comparison. The characterization and antitumor effect of the DOX-incorporated PAA-g-PEG/PArg cationic polymeric micelles were investigated in vitro and in vivo. The cytotoxicity experiments demonstrated that the PAA-g-PEG/PArg micelles have good biocompatibility. Compared with DOX-incorporated PAA-g-PEG micelles, the DOX-incorporated PAA-g-PEG/PArg micelles were more efficiently internalized into human hepatocellular carcinoma (HepG2) cells and more rapidly released DOX into the cytoplasm to inhibit cell proliferation. In the 4T1-bearing nude mouse tumor models, the DOX-incorporated PAA-g-PEG/PArg micelles could efficiently accumulate in the tumor site and had a longer accumulation time and more significant aggregation concentration than those of PAA-g-PEG micelles. Meanwhile, it excellently inhibited the solid tumor growth and extended the survival period of the tumor-bearing Balb/c mice. These results could be attributed to their appropriate nanosize and the cell-penetrating peculiarity of polyarginine as a surface layer. The PAA-g-PEG/PArg polymeric micelles as a safe and high efficiency drug delivery system were expected to be a promising delivery carrier that targeted hydrophobic chemotherapy drugs to tumors and significantly enhanced antitumor effects.

Action of Chlorhexidine, Zingiber officinale, and Calcium Hydroxide on Candida albicans, Enterococcus faecalis, Escherichia coli, and Endotoxin in the Root Canals.

PubMed

Valera, Marcia C; Oliveira, Sarah Ac; Maekawa, Lilian E; Cardoso, Flávia Gr; Chung, Adriana; Silva, Stephanie Fp; Carvalho, Cláudio At

2016-02-01

The purpose of this in vitro study was to evaluate the antimicrobial activity of 2% chlorhexidine gel (CHX) as auxiliary chemical substance and intracanal medications on Candida albicans, Enterococcus faecalis, Escherichia coli, and their endotoxins in the root canals. The study was conducted on 48 single-rooted human teeth divided into four groups (n = 12), according to intracanal medications used: (1) Calcium hydroxide + apyrogenic saline solution (Ca(OH)2 + SS), (2) 20% ginger glycolic extract (GEN), (3) calcium hydroxide + 20% ginger glycolic extract (Ca(OH)2 + GEN), (4) apyrogenic SS (control). Collections were made from the root canal content before preparation (baseline-S1), immediately after instrumentation (S2), 7 days after instrumentation (S3), after 14 days the action of intracanal medication (S4), and 7 days after removal of the intracanal medication (S5). The antimicrobial activity and endotoxin content were analyzed for all collections. The results were statistically analyzed by the Kruskal-Wallis and Dunn tests at a significance level of 5%. After instrumentation with CHX, there was complete elimination of E. coli and C. albicans, except for E. faecalis, which was significantly reduced and then completely eliminated after intracanal medication. There was significant reduction of endotoxin after instrumentation. Comparison of collection after instrumentation and intracanal medication revealed reduction of endotoxins in all groups; this reduction was greater in group Ca(OH)2 followed by the group GEN. It was concluded that the instrumentation using CHX and intracanal medication used were able to eliminate the microorganisms from the root canal; the endotoxins were reduced, yet not completely eliminated. This study is important and relevant for searching alternatives during endodontic therapy, since it aims to study the effect of Zingiber officinale on microorganisms and endotoxins present in root canals.

Polyethylene Glycol 3350 With Electrolytes Versus Polyethylene Glycol 4000 for Constipation: A Randomized, Controlled Trial

PubMed Central

Bekkali, Noor L.H.; Hoekman, Daniël R.; Liem, Olivia; Bongers, Marloes E.J.; van Wijk, Michiel P.; Zegers, Bas; Pelleboer, Rolf A.; Verwijs, Wim; Koot, Bart G.P.; Voropaiev, Maksym; Benninga, Marc A.

2018-01-01

ABSTRACT Objective: The long-term efficacy and safety of polyethylene glycol (PEG) in constipated children are unknown, and a head-to-head comparison of the different PEG formulations is lacking. We aimed to investigate noninferiority of PEG3350 with electrolytes (PEG3350 + E) compared to PEG4000 without electrolytes (PEG4000). Methods: In this double-blind trial, children aged 0.5 to 16 years with constipation, defined as a defecation frequency of <3 times per week, were randomized to receive either PEG3350 + E or PEG4000. Primary outcomes were change in total sum score (TSS) at week 52 compared to baseline, and dose range determination. TSS was the sum of the severity of 5 constipation symptoms rated on a 4-point scale (0–3). Noninferiority margin was a difference in TSS of ≤1.5 based on a 95%-confidence interval [CI]. Treatment success was defined as a defecation frequency of ≥3 per week with <1 episode of fecal incontinence. Results: Ninety-seven subjects were included, of whom 82 completed the study. Mean reduction in TSS was −3.81 (95% CI: −4.96 to −2.65) and −3.74 (95%CI: −5.08 to −2.40), for PEG3350 + E and PEG4000, respectively. Noninferiority criteria were not met (maximum difference between groups: −1.81 to 1.68). Daily sachet use was: 0 to 2 years: 0.4 to 2.3 and 0.9 to 2.1; 2 to 4 years: 0.1 to 3.5 and 1.2 to 3.2; 4 to 8 years: 1.1 to 2.8 and 0.7 to 3.8; 8 to 16 years 0.6 to 3.7 and 1.0 to 3.7, in PEG3350 + E and PEG4000, respectively. Treatment success after 52 weeks was achieved in 50% and 45% of children, respectively (P = 0.69). Rates of adverse events were similar between groups, and no drug-related serious adverse events occurred. Conclusions: Noninferiority regarding long-term constipation-related symptoms of PEG3350 + E compared to PEG4000 was not demonstrated. However, analysis of secondary outcomes suggests similar efficacy and safety of these agents. PMID:28906317

Reformulating polycaprolactone fumarate to eliminate toxic diethylene glycol: effects of polymeric branching and autoclave sterilization on material properties.

PubMed

Runge, M Brett; Wang, Huan; Spinner, Robert J; Windebank, Anthony J; Yaszemski, Michael J

2012-01-01

Polycaprolactone fumarate (PCLF) is a cross-linkable derivative of polycaprolactone diol that has been shown to be an effective nerve conduit material that supports regeneration across segmental nerve defects and has warranted future clinical trials. Degradation of PCLF (PCLF(DEG)) releases toxic small molecules of diethylene glycol used as the initiator for the synthesis of polycaprolactone diol. In an effort to eliminate this toxic degradation product we present a strategy for the synthesis of PCLF from either propylene glycol (PCLF(PPD)) or glycerol (PCLF(GLY)). PCLF(PPD) is linear and resembles the previously studied PCLF(DEG), while PCLF(GLY) is branched and exhibits dramatically different material properties. The synthesis and characterization of their thermal, rheological, and mechanical properties are reported. The results show that the linear PCLF(PPD) has material properties similar to the previously studied PCLF(DEG). The branched PCLF(GLY) exhibits dramatically lower crystalline properties resulting in lower rheological and mechanical moduli, and is therefore a more compliant material. In addition, the question of an appropriate Food and Drug Administration approvable sterilization method is addressed. This study shows that autoclave sterilization of PCLF materials is an acceptable sterilization method for cross-linked PCLF and has minimal effect on the PCLF thermal and mechanical properties. Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Mixing a sol and a precipitate of block copolymers with different block ratios leads to an injectable hydrogel.

PubMed

Yu, Lin; Zhang, Zheng; Zhang, Huan; Ding, Jiandong

2009-06-08

A facile method to obtain a thermoreversible physical hydrogel was found by simply mixing an aqueous sol of a block copolymer with a precipitate of a similar copolymer but with a different block ratio. Two ABA-type triblock copolymers poly(D,L-lactic acid-co-glycolic acid)-B-poly(ethylene glycol)-B-poly(D,L-lactic acid-co-glycolic acid) (PLGA-PEG-PLGA) were synthesized. One sample in water was a sol in a broad temperature region, while the other in water was just a precipitate. The mixture of these two samples with a certain mix ratio underwent, however, a sol-to-gel-to-precipitate transition upon an increase of temperature. A dramatic tuning of the sol-gel transition temperature was conveniently achieved by merely varying mix ratio, even in the case of a similar molecular weight. Our study indicates that the balance of hydrophobicity and hydrophilicity within this sort of amphiphilic copolymers is critical to the inverse thermal gelation in water resulting from aggregation of micelles. The availability of encapsulation and sustained release of lysozyme, a model protein by the thermogelling systems was confirmed. This "mix" method provides a very convenient approach to design injectable thermogelling biomaterials with a broad adjustable window, and the novel copolymer mixture platform is potentially used in drug delivery and other biomedical applications.

Evaluation in vitro and in vivo of dimethicone transdermal therapeutic systems. Influence of propylene glycol on drug release.

PubMed

Ritschel, W A; Nayak, P M

1987-03-01

Coumarin-containing transdermal drug delivery systems were studied in vitro for drug release and in vivo in rats for drug absorption. The matrix of the transdermal delivery system, dimethicone, was a commercially available silicone elastomer. The devices containing 1, 3 and 5% coumarin released in vitro 8.8 (87.4%), 23.4 (74.5%) and 31.6 mg (63.3%) of drug within 24 h. The device containing 5% coumarin was selected for further studies in which 5, 10, 20, 30, 50 and 70% propylene glycol was added. Up to 20% propylene glycol content did not change the amount released. The preparations with 30, 50 and 70% propylene glycol released 69.3, 73.6 and 87.9%, respectively. The 50 and 70% preparations were physically not acceptable. Only the preparations containing 5% coumarin without propylene glycol and 5% coumarin and 30% propylene glycol in the elastomer were evaluated in vivo. The area under the blood level-time curve of the propylene glycol-containing system was twice that of the device without propylene glycol. Blood levels were maintained between about 2 micrograms/ml and 5 micrograms/ml during the time the device was kept on the skin (24 h).

Influence of nanoparticle concentration on thermo-physical properties of CuO-propylene glycol nanofluids.

PubMed

Suganthi, Kuppusamy Swaminathan; Radhakrishnan, Anju K; Anusha, Natarajan; Rajan, Kalpoondi Sekar

2014-06-01

Experiments were performed on the preparation and characterization of CuO-propylene glycol nanofluids. The influence of nanoparticle concentration and temperature on nanofluid viscosity reveals existence of a range of nanoparticle concentration and temperature in which the viscosity of nanofluid is lower than that of propylene glycol, possibly due to interactions between nanoparticles and propylene glycol. A temperature-independent, thermal conductivity enhancement of 38% was obtained for nanoparticle concentration of 1.5 vol% over a temperature range of 10-60 degrees C. We believe that particle clustering contributes to the thermal conductivity enhancement in CuO-propylene glycol nanofluids.

Determination of the composition of HgCdTe oxide films by neutron activation analysis

NASA Astrophysics Data System (ADS)

Gnade, B.; Simmons, A.; Little, D.; Strong, R.

1987-04-01

The composition of HgCdTe oxides grown by anodic oxidation in a standard KOH/ethylene glycol solution has been determined by neutron activation analysis (NAA). This technique is not hindered by the difficulties normally associated with methods using ion beams or electron beams. Neutron activation analysis has the advantage of being quantitative, and also NAA is not affected by the chemical composition of the matrix. The analysis of the KOH/ethylene glycol oxide film by neutron activation yields Hg:Cd:Te ratios of 0.534:0.19:1, in close agreement with Rutherford backscattering spectroscopy analysis (R.L. Strong et al., J. Vac. Sci. Technol. A4 (4) (1986) 1992).

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.

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.

Synthesis and surface properties of polyurethane end-capped with hybrid hydrocarbon/fluorocarbon double-chain phospholipid.

PubMed

Li, Jiehua; Zhang, Yi; Yang, Jian; Tan, Hong; Li, Jianshu; Fu, Qiang

2013-05-01

To improve hemocompatibility of biomedical polyurethanes (PUs), a series of new fluorinated phospholipid end-capped polyurethanes (FPCPUs) as blending PU additives were designed and synthesized using diphenyl methane diisocyanate and 1,4-butanediol as hard segment, poly(tetramethylene glycol), polypropylene glycol, polycarbonate diols, and polyethylene glycol as soft segments, respectively, aminofunctionalized hybrid hydrocarbon/fluorocarbon double-chain phospholipid as end-capper. The bulk structures and surface properties of the obtained FPCPUs were fully characterized by (1)H NMR, Fourier transform infrared, gel permeation chromatography, X-ray photoelectron spectroscopy, differential scanning calorimetry, atomic force microscopy, and water contact angle measurement. It was found that the phosphatidylcholine groups could enrich on the surfaces and subsurfaces with the help of the fluorocarbon chains and self-assemble into mimic biomembrane on these polymer surfaces. These surfaces could effectively suppress fibrinogen adsorption, as evaluated by enzyme-linked immunosorbent assay method. Our work indicates that the FPCPUs should be one of the most potential modified additives for enhancing hemocompatibility of traditional medical PUs. Copyright © 2012 Wiley Periodicals, Inc.

Experimental study on thermal conductivity of solution combustion synthesized MgO nanoparticles dispersed in water and ethylene glycol (50:50) binary mixture

NASA Astrophysics Data System (ADS)

Suseel Jai Krishnan, S.; P. K., Nagarajan

2017-05-01

In this present investigation, experiments were conducted on the magnesia nanoparticles (8-18 nm) synthesized by the solution combustion method, which was dispersed in the binary mixture of water-ethylene glycol (50:50) to prepare stable MgO-water-ethylene glycol (50:50) nanofluids through continuous 26h ultrasonication. The effect of nanoparticle concentration (0 to 0.2 vol%) and temperature (25°C to 60°C) on the thermal conductivity of the nanofluids was investigated. The results clearly indicate that an increase in the nanoparticle concentration increases the thermal conductivity of the nanofluid. Similarly the thermal conductivity of the nanofluid increases with increase in temperature. The enhanced thermal conductivity in the nanofluids may be due to either or both, the Brownian movement and the nano-interfacial layering. The maximum enhancement of 16% was obtained at 0.2 vol% nanoparticle concentration and at 60°C. An accurate correlation, modeling the thermal conductivity as a function of nanoparticle concentration and temperature was also proposed based on the experimental data.

40 CFR Table 9 to Subpart Ffff of... - Soluble Hazardous Air Pollutants

Code of Federal Regulations, 2010 CFR

2010-07-01

... sulfate 77781 6. Dinitrotoluene (2,4) 121142 7. Dioxane (1,4) 123911 8. Ethylene glycol dimethyl ether 110714 9. Ethylene glycol monobutyl ether acetate 112072 10. Ethylene glycol monomethyl ether acetate...

A prospective study of anti-aging topical therapies using a quantitative method of assessment.

PubMed

Rubino, Corrado; Farace, Francesco; Dessy, Luca A; Sanna, Marco P G; Mazzarello, Vittorio

2005-04-01

In the treatment of photoaged skin, glycolic acid works by removing superficial portions of the epidermis and stimulating dermis regeneration. Vitamins A, C, and E should stimulate collagen production and antioxidants should prevent free radical damage and skin aging. However, the effectiveness of different therapies has often relied on subjective methods of assessment. Histologic analysis has seldom been used because of the drawback of permanent scarring. In the literature, the use of a quantitative method for the assessment of facial rejuvenation has been described: the silicone replica technique. The authors' aim was to promote and recommend the use of this technique and, in particular, to test the effect of glycolic acid and multivitamin- and antioxidant-based products on skin texture. The authors performed a prospective, randomized, double-blind, controlled study on 30 women treated topically in the outer canthal region (crow's-feet area). Patients were divided into three groups (groups A, B, and C); each group consisted of five patients between the ages of 31 and 40 years and five patients between the ages of 41 and 50 years. Group A was treated by glycolic acid application, initially at home for 2 weeks, followed by a higher concentration administered in the office weekly for six applications. Group B was treated by topical application at home of a multivitamin product daily for 3 months. Group C was treated with a cream base (placebo) for 3 months and represented the control group. Skin areas under treatment were photographed and reproduced by the silicone replica technique at baseline and at the end of treatment. This technique reproduces exactly the skin's texture. Digital images were obtained from skin replicas and analyzed by specific software for different parameters: roughness, microsulcus number, and width. Pretreatment and posttreatment values were compared using the Wilcoxon signed-rank test. In group A, microsulcus number and width were statistically decreased, but roughness was not. In groups B and C, parameters were not statistically modified. The silicone replica technique allowed a quantitative analysis of results obtained with different topical therapies. In particular, it confirmed the efficacy of glycolic acid in skin rejuvenation.

One pot synthesis of exchange coupled Nd2Fe14B/alpha-Fe by pechini type sol-gel method.

PubMed

Hussain, Abid; Jadhav, Abhijit P; Baek, Yeon Kyung; Choi, Hul Jin; Lee, Jaeho; Kang, Young Soo

2013-11-01

In this work, a combination of nanoparticles of Nd2Fe14B hard magnetic phase and alpha-Fe soft magnetic phase were synthesized by one pot chemical synthesis technique using sol-gel method. A gel of Nd-Fe-B was prepared using NdCl3 x 6H2O, FeCl3 x 6H2O, H3BO3, citric acid, and ethylene glycol by pechini type sol-gel method. The gel was subsequently calcined and annealed to obtain the mixed oxide powders. The produced metal oxide particles were identified with XRD, SEM, TEM to obtain the crystal structure, shape and domain structure of them. The nanoparticles of mixed phase of Nd2Fe14B/alpha-Fe were obtained from these oxides by a process of reduction-diffusion in vacuum by employing CaH2 as reducing agent. During this process it was optimized by controlling temperature, reaction time and concentration of the reducing agent (CaH2). The phase formation of Nd2Fe14B was resulted by the direct diffusion of NdH2, Fe and B. The magnetic property of produced hard and soft phases was successfully identified with vibrating sample magnetometer (VSM). The mixed domains of the hard and soft phases were identified with selected area electron diffraction method (SAED) patterns.

Relative toxicities of formulated glycol aircraft deicers and pure glycol products to duckweed (Lemna minor)

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

DuFresne, D.L.; Pillard, D.A.

1995-12-31

Ethylene and propylene glycol deicers are commonly used at airports in the US and other countries to both remove snow and ice from aircraft, and to retard the accumulation of those materials. Snow and ice often pile up at airports during the winter and are then flushed into the storm sewer system during warmer temperatures or rainfall. Some of this water containing deicers may enter waterbodies without prior treatment, While previous studies have investigated the effects of deicers on aquatic animals and algae, data are not available on the effects on aquatic macrophytes, Glycol deicers were obtained in the formulatedmore » mixtures used on aircraft; pure ethylene and propylene glycol were obtained from Sigma{reg_sign}. Duckweed (Lemna minor) fronds were exposed to various concentrations of pure and formulated glycol mixtures. The number of fronds at test termination and chlorophyll concentration (measured using a spectrophotometer) were the measured endpoints. Based upon glycol concentration, the formulated products were more toxic than the pure material. These results are consistent with results seen in other animal and plant studies.« less

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.

Non-isothermal crystallization kinetics and characterization of biodegradable poly(butylene succinate-co-neopentyl glycol succinate) copolyesters.

PubMed

Xie, Wen-Jie; Zhou, Xiao-Ming

2015-01-01

Both biodegradable aliphatic neat poly(butylene succinate) (PBS) and poly(butylene succinate-co-neopentyl glycol succinate) (P(BS-co-NPGS)) copolyesters with different 1,4-butanediol/neopentyl glycol ratios were synthesized through a two-step process of transesterification and polycondensation using stannous chloride and 4-Methylbenzenesulfonic acid as the co-catalysts. The structure, non-isothermal crystallization behavior, crystalline morphology and crystal structure of neat PBS and P(BS-co-NPGS) copolyesters were characterized by (1)H NMR, differential scanning calorimetry (DSC), polarized optical microscope (POM) and wide angle X-ray diffraction (WAXD), respectively. The Avrami equation modified by Jeziorny and Mo's method was employed to describe the non-isothermal crystallization kinetics of the neat PBS and its copolyesters. The modified Avrami equation could adequately describe the primary stage of non-isothermal crystallization kinetics of the neat PBS and its copolyesters. Mo's method provided a fairly satisfactory description of the non-isothermal crystallization of neat PBS and its copolyesters. Interestingly, the values of 1/t1/2, Zc and F(T) obtained by the modified Avrami equation and Mo's method analysis indicated that the crystallization rate increased first and then decreased with an increase of NPGS content compared that of neat PBS, whereas the crystallization mechanism almost kept unchanged. The results of tensile testing showed that the ductility of PBS was largely improved by incorporating NPGS units. The elongation at break increased remarkably with increasing NPGS content. In particular, the sample with 20% NPGS content showed around 548% elongation at break. Copyright © 2014 Elsevier B.V. All rights reserved.

40 CFR Table 8 to Subpart Ffff of... - Soluble Hazardous Air Pollutants

Code of Federal Regulations, 2010 CFR

2010-07-01

.... Dinitrotoluene (2,4) 121142 7. Dioxane (1,4) 123911 8. Ethylene glycol dimethyl ether 110714 9. Ethylene glycol monobutyl ether acetate 112072 10. Ethylene glycol monomethyl ether acetate 110496 11. Isophorone 78591 12...

Sorption interactions between ethylene glycol and carbon nanotubes

NASA Astrophysics Data System (ADS)

Butyrskaya, E. V.; Belyakova, N. V.; Nechaeva, L. S.; Shaposhnik, V. A.; Selemenev, V. F.

2017-03-01

The adsorption of ethylene glycol by carbon nanoparticles is studied. Carbon nanoparticles with the highest affinity to ethylene glycol are identified, and an adsorption isotherm is constructed. Based on quantum chemical calculations of the energies of interaction between the sorbate and nanotubes with (4,4) and (6,6) chirality, a change in mechanism is revealed upon the monomolecular adsorption of ethylene glycol on carbon nanotubes, and the adsorption isotherm is thus interpreted.

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.

Molecular Hydrogen Formation from Proximal Glycol Pairs on TiO2(110)

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

Chen, Long; Li, Zhenjun; Smith, R. Scott

2014-04-16

Understanding hydrogen formation on TiO2 surfaces is of great importance as it could provide fundamental insight into water splitting for hydrogen production using solar energy. In this work, hydrogen formation from glycols having different numbers of methyl end-groups have been studied using temperature pro-grammed desorption on reduced, hydroxylated, and oxidized TiO2(110) surfaces. The results from OD-labeled glycols demon-strate that gas-phase molecular hydrogen originates exclusively from glycol hydroxyl groups. The yield is controlled by a combi-nation of glycol coverage, steric hindrance, TiO2(110) order and the amount of subsurface charge. Combined, these results show that proximal pairs of hydroxyl aligned glycol moleculesmore » and subsurface charge are required to maximize the yield of this redox reaction. These findings highlight the importance of geometric and electronic effects in hydrogen formation from adsorbates on TiO2(110).« less

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.

Evaluation of effectiveness of hyaluronic acid in combination with bioresorbable membrane (poly lactic acid-poly glycolic acid) for the treatment of infrabony defects in humans: A clinical and radiographic study

PubMed Central

Sehdev, Bhumika; Bhongade, Manohar Laxmanrao; Ganji, Kiran Kumar

2016-01-01

Background: The combination of biomaterials, bone graft substitutes along with guided tissue regeneration (GTR) has been shown to be an effective modality of periodontal regenerative therapy for infrabony defects. Therefore, the present randomized controlled clinical study was undertaken to evaluate the effectiveness of hyaluronic acid (HA) in combination with bioresorbable membrane for the treatment of human infrabony defects. Materials and Methods: Twenty four infrabony defects in 20 systemically healthy patients were randomly assigned to test (HA in combination with bioresorbable membrane) and control (bioresorbable membrane alone) treatment groups. Probing pocket depth (PPD), relative attachment level, and relative gingival margin level were measured with a computerized Florida disc probe at baseline and at 6 months follow-up. Radiographic measurements were also evaluated at baseline and at 6 months of postsurgery. Results: At 6 months, the mean reduction in PPD in test group and control group was 4.52 mm and 2.97 mm, respectively. Significantly higher clinical attachment level with a gain of 2.20 mm was found in the test group as compared to control group. In addition, statistically significant greater reduction of radiographic defect depth was observed in the test group. Conclusion: Regenerative approach using hyaloss in combination with GTR for the treatment of human infrabony defects resulted in a significant added benefit in terms of CAL gains, PPD reductions and radiographic defect fill, as well as LBG, compared to the GTR alone. PMID:27041838

A Multi-institutional Clinical Trial of Rectal Dose Reduction via Injected Polyethylene-Glycol Hydrogel During Intensity Modulated Radiation Therapy for Prostate Cancer: Analysis of Dosimetric Outcomes

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

Song, Danny Y., E-mail: dsong2@jhmi.edu; Herfarth, Klaus K.; Uhl, Matthias

2013-09-01

Purpose: To characterize the effect of a prostate-rectum spacer on dose to rectum during external beam radiation therapy for prostate cancer and to assess for factors correlated with rectal dose reduction. Methods and Materials: Fifty-two patients at 4 institutions were enrolled into a prospective pilot clinical trial. Patients underwent baseline scans and then were injected with perirectal spacing hydrogel and rescanned. Intensity modulated radiation therapy plans were created on both scans for comparison. The objectives were to establish rates of creation of ≥7.5 mm of prostate-rectal separation, and decrease in rectal V70 of ≥25%. Multiple regression analysis was performed tomore » evaluate the associations between preinjection and postinjection changes in rectal V70 and changes in plan conformity, rectal volume, bladder volume, bladder V70, planning target volume (PTV), and postinjection midgland separation, gel volume, gel thickness, length of PTV/gel contact, and gel left-to-right symmetry. Results: Hydrogel resulted in ≥7.5-mm prostate-rectal separation in 95.8% of patients; 95.7% had decreased rectal V70 of ≥25%, with a mean reduction of 8.0 Gy. There were no significant differences in preinjection and postinjection prostate, PTV, rectal, and bladder volumes. Plan conformities were significantly different before versus after injection (P=.02); plans with worse conformity indexes after injection compared with before injection (n=13) still had improvements in rectal V70. In multiple regression analysis, greater postinjection reduction in V70 was associated with decreased relative postinjection plan conformity (P=.01). Reductions in V70 did not significantly vary by institution, despite significant interinstitutional variations in plan conformity. There were no significant relationships between reduction in V70 and the other characteristics analyzed. Conclusions: Injection of hydrogel into the prostate-rectal interface resulted in dose reductions to rectum for >90% of patients treated. Rectal sparing was statistically significant across a range of 10 to 75 Gy and was demonstrated within the presence of significant interinstitutional variability in plan conformity, target definitions, and injection results.« less

Protective Effect of Propolis in Proteinuria, Crystaluria, Nephrotoxicity and Hepatotoxicity Induced by Ethylene Glycol Ingestion.

PubMed

El Menyiy, Nawal; Al Waili, Noori; Bakour, Meryem; Al-Waili, Hamza; Lyoussi, Badiaa

2016-10-01

Propolis is a natural honeybee product with wide biological activities and potential therapeutic properties. The aim of the study is to evaluate the protective effect of propolis extract on nephrotoxicity and hepatotoxicity induced by ethylene glycol in rats. Five groups of rats were used. Group 1 received drinking water, group 2 received 0.75% ethylene-glycol in drinking water, group 3 received 0.75% ethylene-glycol in drinking water along with cystone 500 mg/kg/body weight (bw) daily, group 4 received 0.75% ethylene-glycol in drinking water along with propolis extract at a dose of 100 mg/kg/bw daily, and group 5 received 0.75% ethylene-glycol in drinking water along with propolis extract at a dose of 250 mg/kg/bw daily. The treatment continued for a total of 30 d. Urinalyses for pH, crystals, protein, creatinine, uric acid and electrolytes, and renal and liver function tests were performed. Ethylene-glycol increased urinary pH, urinary volume, and urinary calcium, phosphorus, uric acid and protein excretion. It decreased creatinine clearance and magnesium and caused crystaluria. Treatment with propolis extract or cystone normalized the level of magnesium, creatinine, sodium, potassium and chloride. Propolis is more potent than cystone. Propolis extract alleviates urinary protein excretion and ameliorates the deterioration of liver and kidney function caused by ethylene glycol. Propolis extract has a potential protective effect against ethylene glycol induced hepatotoxicity and nephrotoxicity and has a potential to treat and prevent urinary calculus, crystaluria and proteinuria. Copyright © 2016 IMSS. Published by Elsevier Inc. All rights reserved.

Materials and methods for preventing and treating anastomotic leaks

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

Alverdy, John C.

Materials and methods for preventing and treating anastomotic leaks are disclosed. Data establishes that pathogenic microbes interfere with establishing epithelial cell barriers in anastomoses and, more generally, with the reconnection of any two portions of like or different tissues comprising epithelia. Suitable prophylactic and therapeutic composition comprise, e.g., a phosphorylated high molecular weight polyethylene glycol compound.

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

Code of Federal Regulations, 2010 CFR

2010-07-01

... information, and any information on methods for protecting against such risk, into an MSDS as described at... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF... substance is any manner or method of manufacture, import, or processing associated with any use of this...

40 CFR 721.10661 - Methylenebis[isocyanatobenzene], polymer with alkanedoic acid, alkylene glycols, alkoxylated...

Code of Federal Regulations, 2013 CFR

2013-07-01

...], polymer with alkanedoic acid, alkylene glycols, alkoxylated alkanepolyol and substituted trialkoxysilane... Specific Chemical Substances § 721.10661 Methylenebis[isocyanatobenzene], polymer with alkanedoic acid... as methylenebis[isocyanatobenzene], polymer with alkanedoic acid, alkylene glycols, alkoxylated...

DOUBLE-BLIND PROSPECTIVE RANDOMIZED STUDY COMPARING POLYETHYLENE GLYCOL TO LACTULOSE FOR BOWEL PREPARATION IN COLONOSCOPY

PubMed Central

MENACHO, Aline Moraes; REIMANN, Adriano; HIRATA, Lie Mara; GANZERELLA, Caroline; IVANO, Flavio Heuta; SUGISAWA, Ricardo

2014-01-01

Background Colonoscopy is the most frequent exam used to evaluate colonic mucosa, allowing the diagnosis and treatment of many diseases. The appropriate bowel preparation is indispensable for the realization of colonoscopy. Therefore, it is necessary the use of laxative medications, preferentially by oral administration. Aim To compare two medications used in bowel preparation in adult patients going to ambulatory colonoscopy and to analyze the patients' profile. Methods A double-blind prospective study with 200 patients, randomized in two groups: one that received polyethilene glycol and another that received lactulose. The patients answered to questionnaires to data compilation, as tolerance, symptoms and complications related to preparation. Besides, it was also evaluated the prepare efficacy related to the presence of fecal residue. Results Intestinal habit alterations and abdominal pain were the main reasons to realize the exams and hypertension was the most prevalent comorbidity. Ten percent of the ones who received lactulose didn't get to finish the preparation and 50% considered the taste "bad, but tolerable". The most common subjective symptom after the medication was nausea, especially after lactulose. During the exam, most of the patients who used lactulose had a "light discomfort" and the ones who used polyethilene glycol considered the discomfort as "tolerable". The quality of the preparation was good in 75%, undependable of the medication that was used. Conclusion Polyethilene glycol was more tolerable when compared to lactulose, without difference on the quality of the preparation. PMID:24676290

Echogenic Glycol Chitosan Nanoparticles for Ultrasound-Triggered Cancer Theranostics

PubMed Central

Min, Hyun Su; You, Dong Gil; Son, Sejin; Jeon, Sangmin; Park, Jae Hyung; Lee, Seulki; Kwon, Ick Chan; Kim, Kwangmeyung

2015-01-01

Theranostic nanoparticles hold great promise for simultaneous diagnosis of diseases, targeted drug delivery with minimal toxicity, and monitoring of therapeutic efficacy. However, one of the current challenges in developing theranostic nanoparticles is enhancing the tumor-specific targeting of both imaging probes and anticancer agents. Herein, we report the development of tumor-homing echogenic glycol chitosan-based nanoparticles (Echo-CNPs) that concurrently execute cancer-targeted ultrasound (US) imaging and US-triggered drug delivery. To construct this novel Echo-CNPs, an anticancer drug and bioinert perfluoropentane (PFP), a US gas precursor, were simultaneously encapsulated into glycol chitosan nanoparticles using the oil in water (O/W) emulsion method. The resulting Echo-CNPs had a nano-sized particle structure, composing of hydrophobic anticancer drug/PFP inner cores and a hydrophilic glycol chitosan polymer outer shell. The Echo-CNPs had a favorable hydrodynamic size of 432 nm, which is entirely different from the micro-sized core-empty conventional microbubbles (1-10 μm). Furthermore, Echo-CNPs showed the prolonged echogenicity via the sustained microbubble formation process of liquid-phase PFP at the body temperature and they also presented a US-triggered drug release profile through the external US irradiation. Interestingly, Echo-CNPs exhibited significantly increased tumor-homing ability with lower non-specific uptake by other tissues in tumor-bearing mice through the nanoparticle's enhanced permeation and retention (EPR) effect. Conclusively, theranostic Echo-CNPs are highly useful for simultaneous cancer-targeting US imaging and US-triggered delivery in cancer theranostics. PMID:26681985

Enantiomeric fraction of styrene glycol as a biomarker of occupational risk exposure to styrene.

PubMed

Lima, J J; Aguilar, A; Sánchez, F G; Díaz, A N

2017-02-01

This work reports a new analytical approach for monitoring the enantiomeric ratios of styrene glycol (SG), encountered during the manufacture of plastics, by chiral liquid chromatography and the application as a biomarker for exposure to styrene. The isomers were separated using an AGP column running in the reverse phase and isocratic mode with a mobile phase consisting of 20 mM phosphate buffer saline (pH 4.15) and methanol at a flow rate of 0.8 mL/min. Photometric, polarimetric, and circular dichroism detectors were employed. The chromatographic enantioselective resolution (Rs) and selectivity index (α) values were determined to be 1.60 and 1.48 (by photometric detection), respectively. Calibration curves used for the quantification of the SG enantiomers were linear with a correlation coefficient >0.99; the detection limits were in the range of 0.03-0.16 μg, depending on the detector used. Recovery assays on synthetic samples (in triplicate) covering the full range of enantiomeric fractions (0.0-1.0) show accuracy values below 5% for the enantiomeric fraction (EF) in every case. An alternative method based on the measurement of anisotropy factors for the determination of EF, which is faster and does not require the separation of enantiomers, has also been developed. The enantiomeric excess of the toxicant biomarker styrene glycol has been determined. No previous direct enantioselective determination of styrene glycol was published. Copyright © 2016 Elsevier Ltd. All rights reserved.

Rate of Glycolate Formation During Photosynthesis at High pH 1

PubMed Central

Orth, Gertrude M.; Tolbert, N. E.; Jimenez, Eduardo

1966-01-01

The products of C14O2 fixation by Chlamydomonas and Chlorella were studied under conditions most favorable for glycolate synthesis. The highest percentage of the C14 was incorporated into glycolate in the pH range of 8 to 9. After 1 to 2 minutes as much as 40% of the C14 was found in glycolate products and only a trace of C14 was present as phosphoglycerate. Below pH 8 the rate of photosynthesis was much faster, but only a small percent of the C14 was incorporated into glycolate in 1 or 2 minutes, while a high percent of the C14 accumulated in phosphoglycerate. C14 labeling of glycolate even at pH 8 or above did not occur at times shorter than 10 seconds. During the first seconds of photosynthesis, nearly all of the C14 was found in phosphoglycerate and sugar phosphates. Thus glycolate appears to be formed after the phosphate esters of the photosynthetic carbon cycle. Washing Chlamydomonas with water 2 or 3 times resulted in the loss of most of their free phosphate. When a small aliquot of NaHC14O3 was added to washed algae in the absence of this buffering capacity, the pH of the algal medium became 8 or above and much of the fixed C14 accumulated in glycolate. PMID:16656223

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...

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...

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...

40 CFR Table 9 to Subpart Ggg of... - Default Biorates for Soluble HAP

Code of Federal Regulations, 2010 CFR

2010-07-01

....178 Dinitrotoluene(2,4) 0.784 Dioxane(1,4) 0.393 Ethylene glycol dimethyl ether 0.364 Ethylene glycol monobutyl ether acetate 0.496 Ethylene glycol monomethyl ether acetate 0.159 Isophorone 0.598 Methanol a...

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...

Theory for polymer analysis using nanopore-based single-molecule mass spectrometry

PubMed Central

Reiner, Joseph E.; Kasianowicz, John J.; Nablo, Brian J.; Robertson, Joseph W. F.

2010-01-01

Nanometer-scale pores have demonstrated potential for the electrical detection, quantification, and characterization of molecules for biomedical applications and the chemical analysis of polymers. Despite extensive research in the nanopore sensing field, there is a paucity of theoretical models that incorporate the interactions between chemicals (i.e., solute, solvent, analyte, and nanopore). Here, we develop a model that simultaneously describes both the current blockade depth and residence times caused by individual poly(ethylene glycol) (PEG) molecules in a single α-hemolysin ion channel. Modeling polymer-cation binding leads to a description of two significant effects: a reduction in the mobile cation concentration inside the pore and an increase in the affinity between the polymer and the pore. The model was used to estimate the free energy of formation for K+-PEG inside the nanopore (≈-49.7 meV) and the free energy of PEG partitioning into the nanopore (≈0.76 meV per ethylene glycol monomer). The results suggest that rational, physical models for the analysis of analyte-nanopore interactions will develop the full potential of nanopore-based sensing for chemical and biological applications. PMID:20566890

Reduction of inflammatory responses and enhancement of extracellular matrix formation by vanillin-incorporated poly(lactic-co-glycolic acid) scaffolds.

PubMed

Lee, Yujung; Kwon, Jeongil; Khang, Gilson; Lee, Dongwon

2012-10-01

Vanillin is one of the major components of vanilla, a commonly used flavoring agent and preservative and is known to exert potent antioxidant and anti-inflammatory activities. In this work, vanillin-incorporated poly(lactic-co-glycolic acid) (PLGA) films and scaffolds were fabricated to evaluate the effects of vanillin on the inflammatory responses and extracellular matrix (ECM) formation in vitro and in vivo. The incorporation of vanillin to PLGA films induced hydrophilic nature, resulting in the higher cell attachment and proliferation than the pure PLGA film. Vanillin also reduced the generation of reactive oxygen species (ROS) in cells cultured on the pure PLGA film and significantly inhibited the PLGA-induced inflammatory responses in vivo, evidenced by the reduced accumulation of inflammatory cells and thinner fibrous capsules. The effects of vanillin on the ECM formation were evaluated using annulus fibrous (AF) cell-seeded porous PLGA/vanillin scaffolds. PLGA/vanillin scaffolds elicited the more production of glycosaminoglycan and collagen than the pure PLGA scaffold, in a concentration-dependent manner. Based on the low level of inflammatory responses and enhanced ECM formation, vanillin-incorporated PLGA constructs make them promising candidates in the future biomedical applications.

The integration of constructed wetlands into a treatment system for airport runoff.

PubMed

Revitt, D M; Worral, P; Brewer, D

2001-01-01

A new surface runoff treatment system has been designed for London Heathrow Airport, which incorporates separate floating constructed wetlands or reedbeds and sub-surface flow constructed wetlands as major pollutant removal systems. The primary requirement of the newly developed treatment system is to control the concentrations of glycols following their use as de-icers and anti-icers within the airport. The ability of reedbeds to contribute to this treatment role was fully tested through pilot scale, on-site experiments over a 2 year period. The average reductions in runoff BOD concentrations achieved by pilot scale surface flow and sub-surface flow reedbeds were 30.9% and 32.9%, respectively. The corresponding average glycol removal efficiencies were 54.2% and 78.3%, following shock dosing inputs. These treatment performances are used to predict the required full scale constructed wetland surface areas needed to attain the desired effluent water quality. The treatment system also incorporates aeration, storage and, combined with reedbed technology, has been designed to reduce a mixed inlet BOD concentration of 240 mg/l to less than 40 mg/l for water temperatures varying between 6 degrees C and 20 degrees C.

Manipulation and Biological Applications of Gold Nanorods

NASA Astrophysics Data System (ADS)

Rostro-Kohanloo, Betty Catalina

This thesis compared anionic polyelectrolyte wrapping stabilization with poly(sodium 4-stryene-sulfonate), (PSS), polyelectrolyte and methoxy (polyethylene glycol)-thiol (mPEG(5000)-SH) strategies. From this data the critical gold nanorod (GNR) and cetyl-trimethylammonium bromide (CTAB) concentration ratio needed for GNR stabilization was determined using optical and chemical extraction methods. This was followed by functionalization with a heterobifunctional Polyethylene glycol (PEG) linker, such as a-thio-w-carboxy poly(ethylene glycol) termed t-PEG-c and carbodiimide chemistries for antibody linkage with Immunoglobulin G (IgG), and epidermal growth factor receptor (EGFR) based Human Epidermal growth factor Receptor 2 (Her2), and Cetuximab (C225) antibodies, for in vitro cancer cell targeting. Confocal, two-photon luminescence (TPL), and dark scattering microscopy, and fluorescence, zeta potential, and Nanoparticle Enzyme-linked immunosorbent assay (ELISA) were used to monitor changes to the GNR surface. An untreatable form of bladder cancer was then studied using the t-GNR-PEG-c-Ab bioconjugates with C225 antibody, which housed a glyceraldehyde-3-phosphate (GAPDH), Fluorescein isothiocyanate (FITC) labeled siRNA, termed GAPDH-siRNA-FITC, which was included within a Luciferase based plasmid. A salt based electrostatic heating method was used to trap the GAPDH-siRNA-FITC from the PEG layer by activating the PEG polymer pour point, while a laser based heating system was used for in vitro release inside cancer cells. The down regulation of the GAPDH gene was targeted by the siRNA. as GAPDH has been shown to be up-regulated in many cancers and down-regulated by chemotherapeutic drugs. Cell culture, and subsequent imaging by transmission electron microscopy (TEM), TPL and confocal microscopy were used to view the internalized conjugates, and reverse transcriptase polymerase chain reaction (RT-PCR) were used to determine if the release of the GAPDH-siRNA caused a reduction in the expression of GAPDH-mRNA. Plasmonic gene silencing of the gene by the GAPDH-siRNA was then compared to a lipid based Dharmafect control in terms of transfection ability. RT-PCR results evidenced gene silencing of the plasmonic-GAPDH-siRNA vector when compared to the Dharmafect control. Silencing likely resulted from the zwitterionic charges of the plasmonic vector and the encapsulated GAPDH-siRNA, which yielded near neutral charge tendencies. This differs significantly from the Dharmafect lipid vector, which is cationic in nature. Endosomal release of the plasmonic vector is further enhanced by the laser excitation of the GNR at the longitudinal surface plasmon resonance (LSPR), which allows for the endosomal release of the GAPDH-siRNA through pore formation leading to cytoplasmic transport and subsequent gene silencing. Near neutral charges were welcomed in this plasmonic gene therapy study as they tend to favor endosomal release, pore formation, and transport.

Molecular structure impacts on secondary organic aerosol formation from glycol ethers

NASA Astrophysics Data System (ADS)

Li, Lijie; Cocker, David R.

2018-05-01

Glycol ethers, a class of widely used solvents in consumer products, are often considered exempt as volatile organic compounds based on their vapor pressure or boiling points by regulatory agencies. However, recent studies found that glycol ethers volatilize at ambient conditions nearly as rapidly as the traditional high-volatility solvents indicating the potential of glycol ethers to form secondary organic aerosol (SOA). This is the first work on SOA formation from glycol ethers. The impact of molecular structure, specifically -OH, on SOA formation from glycol ethers and related ethers are investigated in the work. Ethers with and without -OH, with methyl group hindrance on -OH and with -OH at different location are studied in the presence of NOX and under "NOX free" conditions. Photooxidation experiments under different oxidation conditions confirm that the processing of ethers is a combination of carbonyl formation, cyclization and fragmentation. Bulk SOA chemical composition analysis and oxidation products identified in both gas and particle phase suggests that the presence and location of -OH in the carbon bond of ethers determine the occurrence of cyclization mechanism during ether oxidation. The cyclization is proposed as a critical SOA formation mechanism to prevent the formation of volatile compounds from fragmentation during the oxidation of ethers. Glycol ethers with -CH2-O-CH2CH2OH structure is found to readily form cyclization products, especially with the presence of NOx, which is more relevant to urban atmospheric conditions than without NOx. Glycol ethers are evaluated as dominating SOA precursors among all ethers studied. It is estimated that the contribution of glycol ethers to anthropogenic SOA is roughly 1% of the current organic aerosol from mobile sources. The contribution of glycol ethers to anthropogenic SOA is roughly 1% of the current organic aerosol from mobile sources and will play a more important role in future anthropogenic SOA formation.

Anaerobic ethylene glycol degradation by microorganisms in poplar and willow rhizospheres.

PubMed

Carnegie, D; Ramsay, J A

2009-07-01

Although aerobic degradation of ethylene glycol is well documented, only anaerobic biodegradation via methanogenesis or fermentation has been clearly shown. Enhanced ethylene glycol degradation has been demonstrated by microorganisms in the rhizosphere of shallow-rooted plants such as alfalfa and grasses where conditions may be aerobic, but has not been demonstrated in the deeper rhizosphere of poplar or willow trees where conditions are more likely to be anaerobic. This study evaluated ethylene glycol degradation under nitrate-, and sulphate-reducing conditions by microorganisms from the rhizosphere of poplar and willow trees planted in the path of a groundwater plume containing up to 1.9 mol l(-1) (120 g l(-1)) ethylene glycol and, the effect of fertilizer addition when nitrate or sulphate was provided as a terminal electron acceptor (TEA). Microorganisms in these rhizosphere soils degraded ethylene glycol using nitrate or sulphate as TEAs at close to the theoretical stoichiometric amounts required for mineralization. Although the added nitrate or sulphate was primarily used as TEA, TEAs naturally present in the soil or CO(2) produced from ethylene glycol degradation were also used, demonstrating multiple TEA usage. Anaerobic degradation produced acetaldehyde, less acetic acid, and more ethanol than under aerobic conditions. Although aerobic degradation rates were faster, close to 100% disappearance was eventually achieved anaerobically. Degradation rates under nitrate-reducing conditions were enhanced upon fertilizer addition to achieve rates similar to aerobic degradation with up to 19.3 mmol (1.20 g) of ethylene glycol degradation l(-1) day(-1) in poplar soils. This is the first study to demonstrate that microorganisms in the rhizosphere of deep rooted trees like willow and poplar can anaerobically degrade ethylene glycol. Since anaerobic biodegradation may significantly contribute to the phytoremediation of ethylene glycol in the deeper subsurface, the need for "pump and treat" or an aerobic treatment would be eliminated, hence reducing the cost of treatment.

Production of thymine glycols in DNA by radiation and chemical carcinogens as detected by a monoclonal antibody.

PubMed Central

Leadon, S. A.

1987-01-01

In order to understand the role in carcinogenesis of damage indirectly induced by chemical carcinogens, it is important to identify the primary DNA lesions. We have measured the formation and repair of one type of DNA modification, 5,6-dihydroxydihydrothymine (thymine glycol), following exposure of cultured human cells to the carcinogens N-hydroxy-2-naphthylamine or benzo(a)pyrene. The efficiency of production of thymine glycols in DNA by these carcinogens was compared to that by ionizing radiation and ultraviolet light. Thymine glycols were detected using a monoclonal antibody against this product in a sensitive immunoassay. We found that thymine glycols were produced in DNA in a dose dependent manner after exposure to the carcinogens and that their production was reduced if either catalase or superoxide dismutase or both were present at the time of treatment. The efficiency of thymine glycol production following exposure to the chemical carcinogens was greater than that following equi-toxic doses of radiation. Thymine glycols were efficiently removed from the DNA of human cells following treatment with either the chemical carcinogens, ionizing radiation or ultraviolet light. PMID:3477281

Fermentation of glycolate by a pure culture of a strictly anaerobic gram-positive bacterium belonging to the family Lachnospiraceae.

PubMed

Janssen, Peter H; Hugenholtz, Philip

2003-05-01

The component bacteria of a three-membered mixed culture able to ferment glycolate to acetate, propionate and CO(2) were isolated in pure culture. All three strains were strict anaerobes that, on the basis of comparative 16S rRNA gene sequence analysis, belonged to the order Clostridiales in the phylum Firmicutes (low G+C gram-positive bacteria). Two of the strains were not involved in glycolate metabolism. The third, the glycolate-fermenting strain 19gly4 (DSM 11261), was related to members of the family Lachnospiraceae. The cells of strain 19gly4 were oval- to lemon-shaped, 0.85 microm long and 0.65 microm in diameter, occurring singly, in pairs, or in chains of up to 30 cells. Strain 19gly4 fermented glycolate or fumarate to acetate, succinate, and CO(2). Hydrogen was not formed, and strain 19gly4 was able to grow on glycolate in pure culture without any syntrophic hydrogen transfer and without the use of an external electron acceptor. There was no evidence for homoacetogenic metabolism. This bacterium therefore differs in metabolism from previously reported glycolate-utilising anaerobes.

Combination of microneedling and glycolic acid peels for the treatment of acne scars in dark skin.

PubMed

Sharad, Jaishree

2011-12-01

  Acne scars can cause emotional and psychosocial disturbance to the patient. Various modalities have been used for the treatment of acne scars like punch excision, subcision, peels, microdermabrasion, unfractionated and fractioned lasers. The latest in the treatment armamentarium is microneedling. Acne scars commonly coexist with postinflammatory hyperpigmentation. A combination of microneedling and glycolic acid (GA) peels was found to give excellent results in the treatment of such scars. The aim was to study the efficacy of a combination of microneedling with glycolic peel for the treatment of acne scars in pigmented skin.   Thirty patients in the age group of 20-40 years with atrophic box type or rolling scars with postinflammatory hyperpigmentation were chosen for the study. Two groups were made. The first group comprised of 30 patients in whom only microneedling was performed once in 6 weeks for five sessions. In the second group of 30 patients, a combination of microneedling and 35% GA peels was carried out. Patients from both groups were evaluated on the basis of Echelle d'Evaluation clinique des Cicatrices d'acné classification.   Based on the objective scoring and its statistical analysis, there was significant improvement in superficial and moderately deep scars (grade 1-3). There was also improvement in skin texture, reduction in postacne pigmentation in the second group.   Microneedling is a simple, inexpensive office procedure with no downtime. It is safe in Indian skin (skin types III-IV). The combined sequential treatment with GA peel caused a significant improvement in the acne scars without increasing morbidity. © 2011 Wiley Periodicals, Inc.

Non-aqueous synthesis of water-dispersible Fe3O4-Ca3(PO4)2 core-shell nanoparticles

NASA Astrophysics Data System (ADS)

Liu, HongLing; Wu, JunHua; Min, Ji Hyun; Hou, Peng; Song, Ah-Young; Kim, Young Keun

2011-02-01

The Fe3O4-Ca3(PO4)2 core-shell nanoparticles were prepared by one-pot non-aqueous nanoemulsion with the assistance of a biocompatible triblock copolymer, poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEO-PPO-PEO), integrating the magnetic properties of Fe3O4 and the bioactive functions of Ca3(PO4)2 into single entities. The Fe3O4 nanoparticles were pre-formed first by thermal reduction of Fe(acac)3 and then the Ca3(PO4)2 layer was coated by simultaneous deposition of Ca2 + and PO43 - . The characterization shows that the combination of the two materials into a core-shell nanostructure retains the magnetic properties and the Ca3(PO4)2 shell forms an hcp phase (a = 7.490 Å, c = 9.534 Å) on the Fe3O4 surface. The magnetic hysteresis curves of the nanoparticles were further elucidated by the Langevin equation, giving an estimation of the effective magnetic dimension of the nanoparticles and reflecting the enhanced susceptibility response as a result of the surface covering. Fourier transform infrared (FTIR) analysis provides the characteristic vibrations of Ca3(PO4)2 and the presence of the polymer surfactant on the nanoparticle surface. Moreover, the nanoparticles could be directly transferred to water and the aqueous dispersion-collection process of the nanoparticles was demonstrated for application readiness of such core-shell nanostructures in an aqueous medium. Thus, the construction of Fe3O4 and Ca3(PO4)2 in the core-shell nanostructure has conspicuously led to enhanced performance and multi-functionalities, offering various possible applications of the nanoparticles.

21 CFR 172.765 - Succistearin (stearoyl propylene glycol hydrogen succinate).

Code of Federal Regulations, 2010 CFR

2010-04-01

... HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Other Specific Usage Additives § 172.765 Succistearin (stearoyl propylene glycol hydrogen succinate). The food additive succistearin (stearoyl propylene glycol hydrogen...

40 CFR Table 37 to Subpart G of... - Default Biorates for List 1 Compounds

Code of Federal Regulations, 2010 CFR

2010-07-01

... DIMethyl sulfate 0.178 Dinitrophenol 2,4 0.620 Dinitrotoluene(2,4) 0.784 Dioxane(1,4) 0.393 Ethylene glycol dimethyl ether 0.364 Ethylene glycol monomethyl ether acetate 0.159 Ethylene glycol monobutyl ether acetate...

Improving gas dehydrator efficiency; Glycol losses from dehydrator solved by mist eliminator

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

Franke, S.; Neal, R.; Patel, K.

1989-07-01

Triethylene glycol losses from a natural gas dehydrator unit were costing Winnie Pipeline Co. well over $100/day. Several possible causes had been investigated, and a second, smaller unit had been added because insufficient capacity was thought to cause glycol carryover from the contactor. Eventually, glycol losses were virtually eliminated by replacing the standard mist eliminator pad in the top of the contactor tower with a higher-efficiency type. Use of this type of pad is discussed in this paper.

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

Exposure of German residents to ethylene and propylene glycol ethers in general and after cleaning scenarios.

PubMed

Fromme, H; Nitschke, L; Boehmer, S; Kiranoglu, M; Göen, T

2013-03-01

Glycol ethers are a class of semi-volatile substances used as solvents in a variety of consumer products like cleaning agents, paints, cosmetics as well as chemical intermediates. We determined 11 metabolites of ethylene and propylene glycol ethers in 44 urine samples of German residents (background level study) and in urine samples of individuals after exposure to glycol ethers during cleaning activities (exposure study). In the study on the background exposure, methoxyacetic acid and phenoxyacetic acid (PhAA) could be detected in each urine sample with median (95th percentile) values of 0.11 mgL(-1) (0.30 mgL(-1)) and 0.80 mgL(-1) (23.6 mgL(-1)), respectively. The other metabolites were found in a limited number of samples or in none. In the exposure study, 5-8 rooms were cleaned with a cleaner containing ethylene glycol monobutyl ether (EGBE), propylene glycol monobutyl ether (PGBE), or ethylene glycol monopropyl ether (EGPE). During cleaning the mean levels in the indoor air were 7.5 mgm(-3) (EGBE), 3.0 mgm(-3) (PGBE), and 3.3 mgm(-3) (EGPE), respectively. The related metabolite levels analysed in the urine of the residents of the rooms at the day of cleaning were 2.4 mgL(-1) for butoxyacetic acid, 0.06 mgL(-1) for 2-butoxypropionic acid, and 2.3 mgL(-1) for n-propoxyacetic acid. Overall, our study indicates that the exposure of the population to glycol ethers is generally low, with the exception of PhAA. Moreover, the results of the cleaning scenarios demonstrate that the use of indoor cleaning agents containing glycol ethers can lead to a detectable internal exposure of residents. Copyright © 2012 Elsevier Ltd. All rights reserved.

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.

A study of ethylene glycol exposure and kidney function of aircraft de-icing workers.

PubMed

Gérin, M; Patrice, S; Bégin, D; Goldberg, M S; Vyskocil, A; Adib, G; Drolet, D; Viau, C

1997-01-01

Ethylene glycol levels were measured in 154 breathing zone air samples and in 117 urine samples of 33 aviation workers exposed to de-icing fluid (basket operators, de-icing truck drivers, leads and coordinators) studied during 42 worker-days over a winter period of 2 months at a Montreal airport. Ethylene glycol as vapour did not exceed 22 mg/m3 (mean duration of samples 50 min). Mist was quantified at higher levels in 3 samples concerning 1 coordinator and 2 basket operators (76-190 mg/m3, 45-118 min). In 16 cases workers' post-shift or next-morning urine contained quantities of ethylene glycol exceeding 5 mmol/mol creatinine (up to 129 mmol/mol creatinine), with most of these instances occurring in basket operators and coordinators, some of whom did not wear paper masks and/or were accidentally sprayed with de-icing fluid. Diethylene glycol was also found in a few air and urinary samples at levels around one tenth those of ethylene glycol. Urinary concentrations of albumin, beta-N-acetyl-glucosaminidase, beta-2-microglobulin and retinol-binding protein were measured and compared over various periods, according to subgroups based on exposure level and according to the frequency of extreme values. These analyses did not demonstrate acute or chronic kidney damage that could be attributed to working in the presence of ethylene glycol. In conclusion, this study does not suggest important health effects of exposure to de-icing fluid in this group of workers. Potential for overexposure exists, however, in certain work situations, and recommendations on preventive measures are given. In addition, these results suggest that other routes of absorption than inhalation, such as the percutaneous route, may be important and that urinary ethylene glycol may be a useful indicator of exposure to ethylene glycol.

Manipulation of surface morphology of flower-like Ag/ZnO nanorods to enhance photocatalytic performance

NASA Astrophysics Data System (ADS)

U-thaipan, Kasira; Tedsree, Karaked

2018-06-01

The surface morphology of flower-like Ag/ZnO nanorod can be manipulated by adopting different synthetic routes and also loading different levels of Ag in order to alter their surface structures to achieve the maximum photocatalytic efficiency. In a single-step preparation method Ag/ZnO was prepared by heating directly a mixture of Zn2+ and Ag+ precursors in an aqueous NaOH-ethylene glycol solution, while in the two-step preparation method an intermediate of flower-shaped ZnO nanorod was obtained by a hydrothermal process before depositing Ag particles on the ZnO surfaces by chemical reduction. The structure, morphology and optical properties of the synthesized samples were characterized using TEM, SEM, XRD, DRS and PL techniques. The sample prepared by single-step method are characterized with agglomeration of Ag atoms as clusters on the surface of ZnO, whereas in the sample prepared by two-step method Ag atoms are found uniformly dispersed and deposited as discrete Ag nanoparticles on the surface of ZnO. A significant enhancement in the adsorption of visible light was evident for Ag/ZnO samples prepared by two-step method especially with low Ag content (0.5 mol%). The flower-like Ag/ZnO nanorod prepared with 0.5 mol% Ag by two-step process was found to be the most efficient photocatalyst for the degradation of phenol, which can decompose 90% of phenol within 120 min.

Airborne exposures to monoethanolamine, glycol ethers, and benzyl alcohol during professional cleaning: a pilot study.

PubMed

Melchior Gerster, Fabian; Brenna Hopf, Nancy; Pierre Wild, Pascal; Vernez, David

2014-08-01

A growing body of epidemiologic evidence suggests an association between exposure to cleaning products and respiratory dysfunction. Due to the lack of quantitative assessments of respiratory exposures to airborne irritants and sensitizers among professional cleaners, the culpable substances have yet to be identified. Focusing on previously identified irritants, our aims were to determine (i) airborne concentrations of monoethanolamine (MEA), glycol ethers, and benzyl alcohol (BA) during different cleaning tasks performed by professional cleaning workers and assess their determinants; and (ii) air concentrations of formaldehyde, a known indoor air contaminant. Personal air samples were collected in 12 cleaning companies, and analyzed by conventional methods. Nearly all air concentrations [MEA (n = 68), glycol ethers (n = 79), BA (n = 15), and formaldehyde (n = 45)] were far below (<1/10) of the corresponding Swiss occupational exposure limits (OEL), except for ethylene glycol mono-n-butyl ether (EGBE). For butoxypropanol and BA, no OELs exist. Although only detected once, EGBE air concentrations (n = 4) were high (49.48-58.72mg m(-3)), and close to the Swiss OEL (49mg m(-3)). When substances were not noted as present in safety data sheets of cleaning products used but were measured, air concentrations showed no presence of MEA, while the glycol ethers were often present, and formaldehyde was universally detected. Exposure to MEA was affected by its amount used (P = 0.036), and spraying (P = 0.000) and exposure to butoxypropanol was affected by spraying (P = 0.007) and cross-ventilation (P = 0.000). Professional cleaners were found to be exposed to multiple airborne irritants at low concentrations, thus these substances should be considered in investigations of respiratory dysfunctions in the cleaning industry; especially in specialized cleaning tasks such as intensive floor cleaning. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

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...

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...

40 CFR 63.1281 - Control equipment requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... requirements for sources except small glycol dehydration units. Owners and operators of small glycol dehydration units shall comply with the control requirements in paragraph (f) of this section. (1) The control... or operator shall determine glycol dehydration unit baseline operations (as defined in § 63.1271...