21 CFR 520.1846 - Polyoxyethylene (23) lauryl ether blocks.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Polyoxyethylene (23) lauryl ether blocks. 520.1846... Polyoxyethylene (23) lauryl ether blocks. (a) Specifications. Each molasses-based block contains 2.2 percent... (1 pound of block per 500 kilogram (1,100 pound) animal per day). (2) Indications for use. For...
Stanley, F. E.; Warner, A. M.; Schneiderman, E.; Stalcup, A. M.
2009-01-01
This work demonstrates a novel, convenient utilization of capillary electrophoresis (CE) instrumentation for the determination of critical micelle concentrations (CMCs). Solution viscosity differences across a range of surfactant concentrations were monitored by hydrodynamically forcing an analyte towards the detector. Upon reaching the surfactant's CMC value, migration times were observed to change drastically. CMC values for four commonly employed anionic surfactants were determined - sodium dodecyl sulfate: 8.1 mM; sodium caprylate- 300 mM; sodium decanoate- 86 mM; sodium laurate- 30 mM; and found to be in excellent agreement with values previously reported in the literature. The technique was then applied to the less well-characterized nonionic surfactants poly(oxyethylene) 8 myristyl ether (CMC ~ 9 μM), poly(oxyethylene) 8 decyl ether (CMC ~ 0.95 mM) and poly(oxyethylene) 4 lauryl ether. PMID:19836753
NASA Astrophysics Data System (ADS)
Lunter, Dominique; Daniels, Rolf
2014-12-01
A methodology that employs confocal Raman microscopy (CRM) on ex vivo skin samples is proposed for the investigation of drug content and distribution in the skin. To this end, the influence of the penetration enhancers propylene glycol and polyoxyethylene-23-lauryl ether on the penetration and permeation of procaine as a model substance was investigated. The drug content of skin samples that had been incubated with semisolid formulations containing one of these enhancers was examined after skin segmentation. The experiments showed that propylene glycol did not affect the procaine content that was delivered to the skin, whereas polyoxyethylene-23-lauryl ether led to higher procaine contents and deeper penetration. Neither substance was found to influence the permeation rate of procaine. It is thereby shown that CRM can provide additional information on drug penetration and permeation. Furthermore, the method was found to enhance the depth from which Raman spectra can be collected and to improve the depth resolution compared to previously proposed methods.
Removal of Tetranitromethane from Air Streams
1975-10-08
aryl sulfonates, Monsanto Corp., St, Louis, Mo., "Sterox SE", a polyoxyethylene thio ether, Monsanto Corp., "Deysonol", sodium lauryl sulfate , DuPont...910 M_ 50 16 1.06 6 810b 1% Daxad 55 17 1.05 4. 6 500b 0.5% Santomerse S 57 18 1.03 —- — c,b 0.5% Na Lauryl Sulfate — — 20 1.04 4. 6 910 0.5...hydrogen peroxide decomposed much less rapidly and could be used as TNM scavengers. Initial experiments with aqueous solutions of sodium sulfite
Development of and fabrication of high resolution gas chromatographic capillary columns
NASA Technical Reports Server (NTRS)
Zlatkis, A.
1982-01-01
Gas chromatographic columns which are used in the trace gas analyzer (TGA) for the space shuttle are coated with a polyoxyethylene lauryl ether. This stationary phase is of medium polarity and has a temperature limit of 160 C. A polymer for this application which has an improved thermal stability is investigated. The use of fused silica capillary columns with specially bonded phases as well as an introduction system (on column) was also studied.
Lu, Yang; Yao, Hui; Li, Chuang; Han, Juan; Tan, Zhenjiang; Yan, Yongsheng
2016-02-01
Polyoxyethylene lauryl ether (POELE10)-NaH2PO4 aqueous two-phase extraction system (ATPES) is coupled with HPLC to analyze chloramphenicol (CAP) in aquatic product. Response surface methodology (RSM) was adopted in the multi-factor experiment to determine the optimized conditions. The extraction efficiency of CAP (E%) is up to 99.42% under the optimal conditions, namely, the concentration of NaH2PO4, the concentration of POELE10, pH and temperature were 0.186 g · mL(-1), 0.033 g · mL(-1), 3.8 and 25 °C respectively. The optimal value of enrichment factor of CAP (F) was 22.56 when the concentration of NaH2PO4 was 0.192 g · mL(-1), the concentration of POELE10 was 0.024 g/ml, pH was 4.2 and temperature was 30 °C. The limit of detection (LOD) and limit of quantification (LOQ) of this method are 0.8 μg · kg(-1) and 1 μg · kg(-1), which meet the needs of determining trace or ultratrace CAP in food. The E% and F of this technique are much better than other extraction methods. Copyright © 2015 Elsevier Ltd. All rights reserved.
Lu, Yang; Cong, Biao; Tan, Zhenjiang; Yan, Yongsheng
2016-11-01
Polyoxyethylene lauryl ether (POELE10)-Na2C4H4O6 aqueous two-phase extraction system (ATPES) is a novel and green pretreatment technique to trace samples. ATPES coupled with high-performance liquid chromatography (HPLC) is used to analyze synchronously sulfadiazine (SDZ) and sulfamethazine (SMT) in animal by-products (i.e., egg and milk) and environmental water sample. It was found that the extraction efficiency (E%) and the enrichment factor (F) of SDZ and SMT were influenced by the types of salts, the concentration of salt, the concentration of POELE10 and the temperature. The orthogonal experimental design (OED) was adopted in the multi-factor experiment to determine the optimized conditions. The final optimal condition was as following: the concentration of POELE10 is 0.027gmL(-1), the concentration of Na2C4H4O6 is 0.180gmL(-1) and the temperature is 35°C. This POELE10-Na2C4H4O6 ATPS was applied to separate and enrich SDZ and SMT in real samples (i.e., water, egg and milk) under the optimal conditions, and it was found that the recovery of SDZ and SMT was 96.20-99.52% with RSD of 0.35-3.41%. The limit of detection (LOD) of this method for the SDZ and SMT in spiked samples was 2.52-3.64pgmL(-1), and the limit of quantitation (LOQ) of this method for the SDZ and SMT in spiked samples was 8.41-12.15pgmL(-1). Copyright © 2016 Elsevier Inc. All rights reserved.
Effect of vehicle on the nasal absorption of epinephrine during cardiopulmonary resuscitation.
Bleske, B E; Rice, T L; Warren, E W; Giacherio, D A; Gilligan, L J; Massey, K D; Chrisp, C E; Tait, A R
1996-01-01
We have shown in previous studies that epinephrine administered intranasally is a feasible route of administration during cardiopulmonary resuscitation (CPR). To promote the absorption of epinephrine we administered phentolamine prior to epinephrine and used a bile salt as a vehicle to dissolve the epinephrine. The purpose of this study was to compare the effect of two different vehicles (bile salt vs surfactant) in promoting the absorption of nasally administered epinephrine during CPR and to determine their effects on the nasal mucosa. A randomized, blinded study. A controlled laboratory environment. Eleven mongrel dogs. Each dog underwent 3 minutes of unassisted ventricular fibrillation (VF) followed by 7 minutes of VF with CPR. Five minutes after the start of VF, 10 dogs received intranasal phentolamine 0.25 mg/kg/nostril followed 1 minute later by intranasal epinephrine 7.5 mg/kg/nostril. The epinephrine was dissolved in a randomly assigned vehicle consisting of either taurodeoxycholic acid (group A, bile salt) or polyoxyethylene-9-lauryl ether (group B, surfactant). One animal acted as a control and received 0.9% sodium chloride nasally. Data from eight dogs (one control) were included for analysis. Histology of the nasal cavity demonstrated severe multifocal erosion and ulceration of the respiratory epithelium for groups A and B compared with the control. The severity was similar between the two groups. In addition, no significant differences in plasma epinephrine concentrations or blood pressure responses were seen between the groups. Based on histology, polyoxyethylene-9-lauryl ether offered no advantage over taurodeoxycholic acid in its effect on the nasal mucosa. The data available for changes in epinephrine concentration and pressure also suggest no difference between the two vehicles in promoting the absorption of epinephrine during CPR in an animal model.
Direct Observation Of Nanoparticle-Surfactant Interactions Using Small Angle Neutron Scattering
NASA Astrophysics Data System (ADS)
Kumar, Sugam; Aswal, V. K.
2010-12-01
Interactions of anionic silica nanoparticles with anionic, cationic and nonionic surfactants have directly been studied by contrast variation small angle neutron scattering (SANS). The measurements are performed on 1 wt% of both silica nanoparticles and surfactants of anionic sodium dodecyle sulphate (SDS), cationic dodecyltrimethyl ammonium bromide (DTAB) and non-ionic polyoxyethylene 10 lauryl ether (C12E10) in aqueous solution. We show that there is no direct interaction in the case of SDS with silica particles, whereas strong interaction for DTAB leads to the aggregation of silica particles. The interaction of C12E10 is found through the micelles adsorbed on the silica particles.
Search of non-ionic surfactants suitable for micellar liquid chromatography.
Peris-García, Ester; Rodríguez-Martínez, Jorge; Baeza-Baeza, Juan J; García-Alvarez-Coque, María Celia; Ruiz-Angel, María José
2018-06-19
Most reports in reversed-phase liquid chromatography (RPLC) with micellar mobile phases make use of the anionic sodium dodecyl sulfate. This surfactant masks efficiently the silanol groups that are the origin of the poor efficiencies and tailing peaks observed for basic compounds in conventional RPLC. However, it has the handicap of yielding excessive retention, which forces the addition of an organic solvent to reduce the retention times to practical values. Other surfactants, such as the non-ionic polyoxyethylene(23)lauryl ether (Brij-35), are rarely used. Brij-35 allows the separation of a large range of analytes in adequate retention times, without the need of adding an organic solvent to the mobile phase. However, this non-ionic surfactant shows irreversible adsorption on chromatographic columns and peak shape is poorer. Therefore, the search of non-ionic surfactants with similar properties to Brij-35, but showing reversible adsorption and better peak shape, can be of great interest. In this work, the adequacy of several non-ionic surfactants as modifiers in RPLC has been explored, being polyoxyethylene(10)tridecyl ether particularly attractive. The separation of different types of compounds was checked: sulfonamides (acidic), β-adrenoceptor antagonists and tricyclic antidepressants (basic with diverse polarity), and flavonoids (with and without hydroxyl groups on the aromatic rings). The chromatographic behaviors were examined in terms of retention and peak shape. The results were compared with those obtained with Brij-35.
Influence of different surfactants on the physicochemical properties of elastic liposomes.
Barbosa, R M; Severino, P; Preté, P S C; Santana, M H A
2017-05-01
Elastic liposomes are capable to improve drug transport through the skin by acting as penetration enhancers due to the high fluidity and elasticity of the liposome membranes. Therefore, elastic liposomes were prepared and characterized to facilitate the transdermal transport of bioactive molecules. Liposomes consisted of dimyristoylphosphatidylcholine (DMPC) as the structural component, with different surfactants derived from lauric acid as elastic components: C 12 E 5 (polyoxyethylene-5-lauryl ether), PEG4L (polyethyleneglycol-4-lauryl ester), PEG4DL (polyethylene glycol-4-dilauryl ester), PEG8L (polyethylene glycol-8-lauryl ester) and PEG8DL (polyethylene glycol-8-dilauryl ester). The elastic liposomes were characterized in terms of their phospholipid content, mean diameter, size distribution, elasticity and stability during storage, as well as their ability to incorporate surfactant and permeate through 50 nm pore size membranes. The results showed that the phospholipid phase transition temperature, the fluidity of the lipid bilayer resulting from incorporation of the surfactant and the preservation of particle integrity were factors determining the performance of the elastic liposomes in permeating through nanoporous membranes. The best results were obtained using DMPC combined with the surfactants PEG8L or PEG8DL. The findings demonstrate the potential of using elastic liposomes for transdermal administration of drugs.
Influence of droplet charge on the chemical stability of citral in oil-in-water emulsions.
Choi, Seung Jun; Decker, Eric Andrew; Henson, Lulu; Popplewell, L Michael; McClements, David Julian
2010-08-01
The chemical stability of citral, a flavor component widely used in beverage, food, and fragrance products, in oil-in-water emulsions stabilized by surfactants with different charge characteristics was investigated. Emulsions were prepared using cationic (lauryl alginate, LAE), non-ionic (polyoxyethylene (23) lauryl ether, Brij 35), and anionic (sodium dodecyl sulfate, SDS) surfactants at pH 3.5. The citral concentration decreased over time in all the emulsions, but the rate of decrease depended on surfactant type. After 7 d storage, the citral concentrations remaining in the emulsions were around 60% for LAE- or Brij 35-stabilized emulsions and 10% for SDS-stabilized emulsions. An increase in the local proton (H(+)) concentration around negatively charged droplet surfaces may account for the more rapid citral degradation observed in SDS-stabilized emulsions. A strong metal ion chelator (EDTA), which has previously been shown to be effective at increasing the oxidative stability of labile components, had no effect on citral stability in LAE- or Brij 35-stabilized emulsions, but it slightly decreased the initial rate of citral degradation in SDS-stabilized emulsions. These results suggest the surfactant type used to prepare emulsions should be controlled to improve the chemical stability of citral in emulsion systems.
Effects of Surfactants on Chlorobenzene Absorption on Pyrite Surface
NASA Astrophysics Data System (ADS)
Hoa, P. T.; Suto, K.; Inoue, C.; Hara, J.
2007-03-01
Recently, both surfactant extraction of chlorinated compounds from contaminated soils and chemical reduction of chlorinated compounds by pyrite have had received a lot of attention. The reaction of the natural mineral pyrite was found as a surface controlling process which strongly depends on absorption of contaminants on the surface. Surfactants were not only aggregated into micelle which increase solubility of hydrophobic compounds but also tend to absorb on the solid surface. This study investigated effects of different kinds of Surfactants on absorption of chlorobenzene on pyrite surface in order to identify coupling potential of surfactant application and remediation by pyrite. Surfactants used including non-ionic, anionic and cationic which were Polyoxyethylene (23) Lauryl Ether (Brij35), Sodium Dodecyl Sulfate (SDS) and Cetyl TrimethylAmmonium Bromide (CTAB) respectively were investigated with a wide range of surfactant concentration up to 4 times of each critical micelle concentration (CMC). Chlorobenzene was chosen as a representative compound. The enhancement or competition effects of Surfactants on absorption were discussed.
Nakao, Yusuke; Horiguchi, Michiko; Nakamura, Ryuji; Sasaki-Hamada, Sachie; Ozawa, Chihiro; Funane, Taichi; Ozawa, Ryo; Oka, Jun-Ichiro; Yamashita, Chikamasa
2016-12-30
Depression is a common mental disorder. More than 350 million people of all ages suffer from depression worldwide. Although a number of antidepressants are available, >20% of patients with major depressive disorder suffer from treatment-resistant depression. Therefore, development of novel therapeutics to overcome this condition is required. We reported that intracerebroventricular administration of glucagon-like peptide-2 (GLP-2) exerts antidepressant-like effects treated with or without adrenocorticotropic hormone. In the present study, we developed a nasal formulation of GLP-2 containing 5% polyoxyethylene (25) lauryl ether and 1% β-cyclodextrin that enhanced the resistance of GLP-2 to inactivation by dipeptidyl peptidase-4. Intranasal administration of this formulation (60μg/kg) increased the delivery of GLP-2 to the brain and had antidepressant-like effects on rats. These results suggest the potential of the GLP-2 nasal formulation for use as a novel antidepressant. Copyright © 2016 Elsevier B.V. All rights reserved.
A method for the determination of the anionic Steol CS-330 surfactant is described. CS-330 is a complex mixture of oligomers due to the various sizes of fatty alcohols and the number of moles of the ethoxylation. The main component of CS-330 is sodium lauryl ether sulfate (SLES)....
Enhanced rectal absorption of amphotericin B lyophilized with glycyrrhizinate in rabbits.
Tanaka, M; Kuwahara, E; Takahashi, M; Koyama, O; Takahashi, N; Yotsuyanagi, T
1998-08-01
The influence of bases and additives in the formulation for rectal absorption of amphotericin B (AMB) lyophilized with dipotassium glycyrrhizinate (GLYK) was investigated using rabbits in relation to an in vitro release test. The release of AMB from the fatty base of Witepsol or a medium chain triglyceride (MCT) was markedly faster than that from the hydrophilic base of macrogol. The addition of polyoxyethylene (2) lauryl ether (POE(2)LE) into the fatty bases led to a marked increase in the release rate, whereas POE(9)LE or sodium lauryl sulfate resulted in a significantly lower release rate. Animals received rectally each of seven AMB formulations of Witepsol H-15, macrogol, MCT with surfactants and aqueous solution. The absorption of the AMB lyophilized mixture with GLYK at a 1:9 molar ratio from a MCT base was significantly superior to that from macrogol. The addition of POE(2)LE into the MCT base resulted in a marked increase in bioavailability, showing the highest bioavailability of 4.9%. High serum levels of over 100 ng/ml of serum were maintained for 24 h following administration. The lowest bioavailability was 0.32% for the macrogol suppository. There was a good correlation between the release rate of AMB from the formulations and bioavailability. These results suggest that an AMB rectal formulation may provide a promising therapeutic alternative to infusion, taking into account the serum level of AMB exceeding the minimal inhibitory concentration of the infecting organism.
Effect of Surfactants on Mechanical, Thermal, and Photostability of a Monoclonal Antibody.
Agarkhed, Meera; O'Dell, Courtney; Hsieh, Ming-Ching; Zhang, Jingming; Goldstein, Joel; Srivastava, Arvind
2018-01-01
The purpose of this work was to evaluate the effect of commonly used surfactants (at 0.01% w/v concentration) on mechanical, thermal, and photostability of a monoclonal antibody (MAb1) of IgG1 sub-class and to evaluate the minimum concentration of surfactant (Polysorbate 80) required in protecting MAb1 from mechanical stress. Surfactants evaluated were non-ionic surfactants, Polysorbate 80, Polysorbate 20, Pluronic F-68 (polyoxyethylene-polyoxypropylene block polymer), Brij 35 (polyoxyethylene lauryl ether), Triton X-100, and an anionic surfactant, Caprylic acid (1-Heptanecarboxylic acid). After evaluating effect of surfactants and determining stabilizing effect of Polysorbate 80 against mechanical stress without compromising thermal and photostability of MAb1, the minimum concentration of Polysorbate 80 required for mechanical stability was further examined. Polysorbate 80 concentration was varied from 0 to 0.02%. Mechanical stability was evaluated by agitation of MAb1 at 300 rotations per minute at room temperature for 72 h. Samples were analyzed for purity by SEC-HPLC, turbidity by absorbance at 350 nm, visible particles by visual inspection, and sub-visible particles by light obscuration technique on a particle analyzer. All non-ionic surfactants tested showed a similar effect in protecting against mechanical stress and did not exhibit any significant negative effect on thermal and photostability. However, Caprylic acid had a slightly negative effect on mechanical and photostability when compared to the non-ionic surfactants or sample without surfactant. This work demonstrated that polysorbate 80 is better than other surfactants tested and that a concentration of at least 0.005% (w/v) Polysorbate 80 is needed to protect MAb1 against mechanical stress.
De Vrieze, Mike; Lynen, Frédéric; Chen, Kai; Szucs, Roman; Sandra, Pat
2013-07-01
Several in vitro methods have been tested for their ability to predict drug penetration across the blood-brain barrier (BBB) into the central nervous system (CNS). In this article, the performance of a variety of micellar liquid chromatographic (MLC) methods and immobilized artificial membrane (IAM) liquid chromatographic approaches were compared for a set of 45 solutes. MLC measurements were performed on a C18 column with sodium dodecyl sulfate (SDS), polyoxyethylene (23) lauryl ether (Brij35), or sodium deoxycholate (SDC) as surfactant in the micellar mobile phase. IAM liquid chromatography measurements were performed with Dulbecco's phosphate-buffered saline (DPBS) and methanol as organic modifier in the mobile phase. The corresponding retention and computed descriptor data for each solute were used for construction of models to predict transport across the blood-brain barrier (log BB). All data were correlated with experimental log BB values and the relative performance of the models was studied. SDS-based models proved most suitable for prediction of log BB values, followed closely by a simplified IAM method, in which it could be observed that extrapolation of retention data to 0% modifier in the mobile phase was unnecessary.
Synthesis and characterization of Cr-MSU-1 and its catalytic application for oxidation of styrene
NASA Astrophysics Data System (ADS)
Liu, Hong; Wang, Zhigang; Hu, Hongjiu; Liang, Yuguang; Wang, Mengyang
2009-07-01
Chromium-containing mesoporous silica material Cr-MSU-1 was synthesized using lauryl alcohol-polyoxyethylene (23) ether as templating agent under the neutral pH condition by two-step method. The sample was characterized by XRD, TEM, FT-IR, UV-Vis, ESR, ICP-AES and N 2 adsorption. Its catalytic performance for oxidation of styrene was studied. Effects of the solvent used, the styrene/H 2O 2 mole ratio and the reaction temperature and time on the oxidation of styrene over the Cr-MSU-1 catalyst were examined. The results indicate that Cr ions have been successfully incorporated into the framework of MSU-1 and the Cr-MSU-1 material has a uniform worm-like holes mesoporous structure. After Cr-MSU-1 is calcined, most of Cr 3+ is oxidized to Cr 5+ and Cr 6+ in tetrahedral coordination and no extra-framework Cr 2O 3 is formed. The Cr-MSU-1 catalyst is highly active for the selective oxidation of styrene and the main reaction products over Cr-MSU-1 are benzaldehyde and phenylacetaldehyde. Its catalytic performance remains stable within five repeated runs and no leaching is noticed for this chromium-based catalyst.
Code of Federal Regulations, 2013 CFR
2013-07-01
... Environmental Releases Report November 18, 1994. 112-35-6 Triethylene glycol monomethyl ether Health effects... Health effects November 23, 1993. 994-05-8 Tertiary-amyl methyl ether Health effects March 21, 1995. 1634-04-4 Methyl tert-butyl ether Health effects March 31, 1988. 2461-18-9 Lauryl glycidyl ether 1 Health...
Hirata, Yoshihiko; Ryu, Mizuyuki; Oda, Yuka; Igarashi, Keisuke; Nagatsuka, Asami; Furuta, Taro; Sugiura, Masaki
2009-08-01
Sophorolipids (SLs) are a family of glycolipid type biosurfactants, which are largely produced by the non-pathogenic yeast, Candida bombicola. In order to investigate the possibility of SLs for industrial use, here we examined the interfacial activities, cytotoxicity and biodegradability of SLs, and compared these properties with those of two lipopeptide type biosurfactants (surfactin and arthrofactin), sodium laurate (soap, SP) and four kinds of chemically synthesized surfactants including two block-copolymer nonionic surfactants (BPs), polyoxyethylene lauryl ether (AE) and sodium dodecyl sulfate (SDS). It was indicated that SLs had extremely low-foaming properties and high detergency comparable with commercially available low-foaming BPs. These interfacial activities of SLs were maintained under 100 ppm water hardness. Cytotoxicity of SLs on human keratinocytes was the same as surfactin, which has already been commercialized as cosmetic material, but higher than BPs. Moreover, biodegradability of SLs using the OECD Guidelines for Testing of Chemicals (301C, Modified MITI Test) displayed that SLs can be classified as "readily" biodegradable chemicals, which are defined as chemicals that are degraded 60% within 28 days under specified test methods. We observed 61% degradation of SLs on the eighth day of cultivation. Our results indicate that SLs are low-foaming surfactants with high detergency, which also exhibit both low cytotoxicity and readily biodegradable properties.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sugiura, Masaaki
1992-02-01
Fluxes of 14 kinds of lanthanides across cellulose triacetate membranes were determined by using mixtures of o-nitrophenyl n-octyl ether and a series of polyoxythylene n-alkyl ethers (POE ethers) as plasticizers, and hinokitiol as carrier. Effects of alkyl and polyoxyethylene (POE) chains of POE ether on the flux were demonstrated. The transport of the lanthanides was coupled to a flow of hydrogen ions. The POE ethers used (C{sub n}H{sub 2n+1}(OCH{sub 2}CH{sub 2}){sub x}OH, referred to as C{sub n}E{sub x}) were C{sub 10}E{sub 3}, C{sub 12}E{sub 3}, C{sub 14}E{sub 3}, C{sub 16}E{sub 3}, C{sub 12}E{sub 2}, C{sub 12}E{sub 4}, C{sub 12}E{sub 6}more » and C{sub 12}E{sub 8}, In all cases, high fluxes were observed for the lanthanides from samarium to lutetium. On the contrary, the fluxes for lanthanum to neodymium were extremely low. In experiments testing the effect of the alkyl chain, the order of the POE ethers in the lanthanide flux for samarium to lutetium was C{sub 12}E{sub 3} > C{sub 10}E{sub 3} > C{sub 14}E{sub 3} >C{sub 16}E{sub 3}. In experiments testing the effect of the POE chain, the flux decreased with an increase in the chain length.« less
Interactions between selected bile salts and Triton X-100 or sodium lauryl ether sulfate.
Cirin, Dejan M; Poša, Mihalj M; Krstonošić, Veljko S
2011-12-29
In order to develop colloidal drug carriers with desired properties, it is important to determine physico-chemical characteristics of these systems. Bile salt mixed micelles are extensively studied as novel drug delivery systems. The objective of the present investigation is to develop and characterize mixed micelles of nonionic (Triton X-100) or anionic (sodium lauryl ether sulfate) surfactant having oxyethylene groups in the polar head and following bile salts: cholate, deoxycholate and 7-oxodeoxycholate. The micellization behaviour of binary anionic-nonionic and anionic-anionic surfactant mixtures was investigated by conductivity and surface tension measurements. The results of the study have been analyzed using Clint's, Rubingh's, and Motomura's theories for mixed binary systems. The negative values of the interaction parameter indicate synergism between micelle building units. It was noticed that Triton X-100 and sodium lauryl ether sulfate generate the weakest synergistic interactions with sodium deoxycholate, while 7-oxodeoxycholate creates the strongest attractive interaction with investigated co-surfactants. It was concluded that increased synergistic interactions can be attributed to the larger number of hydrophilic groups at α side of the bile salts. Additionally, 7-oxo group of 7-oxodeoxycholate enhance attractive interactions with selected co-surfactants more than 7-hydroxyl group of sodium cholate.
Interactions between selected bile salts and Triton X-100 or sodium lauryl ether sulfate
2011-01-01
Background In order to develop colloidal drug carriers with desired properties, it is important to determine physico-chemical characteristics of these systems. Bile salt mixed micelles are extensively studied as novel drug delivery systems. The objective of the present investigation is to develop and characterize mixed micelles of nonionic (Triton X-100) or anionic (sodium lauryl ether sulfate) surfactant having oxyethylene groups in the polar head and following bile salts: cholate, deoxycholate and 7-oxodeoxycholate. Results The micellization behaviour of binary anionic-nonionic and anionic-anionic surfactant mixtures was investigated by conductivity and surface tension measurements. The results of the study have been analyzed using Clint's, Rubingh's, and Motomura's theories for mixed binary systems. The negative values of the interaction parameter indicate synergism between micelle building units. It was noticed that Triton X-100 and sodium lauryl ether sulfate generate the weakest synergistic interactions with sodium deoxycholate, while 7-oxodeoxycholate creates the strongest attractive interaction with investigated co-surfactants. Conclusion It was concluded that increased synergistic interactions can be attributed to the larger number of hydrophilic groups at α side of the bile salts. Additionally, 7-oxo group of 7-oxodeoxycholate enhance attractive interactions with selected co-surfactants more than 7-hydroxyl group of sodium cholate. PMID:22206681
Lin, Xuliang; Qiu, Xueqing; Yuan, Long; Li, Zihao; Lou, Hongming; Zhou, Mingsong; Yang, Dongjie
2015-06-01
Water-soluble lignin-based polyoxyethylene ether (EHL-PEG), prepared from enzymatic hydrolysis lignin (EHL) and polyethylene glycol (PEG1000), was used to improve enzymatic hydrolysis efficiency of corn stover. The glucose yield of corn stover at 72h was increased from 16.7% to 70.1% by EHL-PEG, while increase in yield with PEG4600 alone was 52.3%. With the increase of lignin content, EHL-PEG improved enzymatic hydrolysis of microcrystalline cellulose more obvious than PEG4600. EHL-PEG could reduce at least 88% of the adsorption of cellulase on the lignin film measured by quartz crystal microbalance with dissipation monitoring (QCM-D), while reduction with PEG4600 was 43%. Cellulase aggregated at 1220nm in acetate buffer analyzed by dynamic light scattering. EHL-PEG dispersed cellulase aggregates and formed smaller aggregates with cellulase, thereby, reduced significantly nonproductive adsorption of cellulase on lignin and enhanced enzymatic hydrolysis of lignocelluloses. Copyright © 2015 Elsevier Ltd. All rights reserved.
Methods for degrading lignocellulosic materials
Vlasenko, Elena [Davis, CA; Cherry, Joel [Davis, CA; Xu, Feng [Davis, CA
2008-04-08
The present invention relates to methods for degrading a lignocellulosic material, comprising: treating the lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant. The present invention also relates to methods for producing an organic substance, comprising: (a) saccharifying a lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant; (b) fermenting the saccharified lignocellulosic material of step (a) with one or more fermentating microoganisms; and (c) recovering the organic substance from the fermentation.
Methods for degrading lignocellulosic materials
Vlasenko, Elena [Davis, CA; Cherry, Joel [Davis, CA; Xu, Feng [Davis, CA
2011-05-17
The present invention relates to methods for degrading a lignocellulosic material, comprising: treating the lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant. The present invention also relates to methods for producing an organic substance, comprising: (a) saccharifying a lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant; (b) fermenting the saccharified lignocellulosic material of step (a) with one or more fermenting microorganisms; and (c) recovering the organic substance from the fermentation.
Methods for degrading lignocellulosic materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vlasenko, Elena; Cherry, Joel; Xu, Feng
2008-04-08
The present invention relates to methods for degrading a lignocellulosic material, comprising: treating the lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant. The present invention also relates to methods for producing an organic substance, comprising: (a) saccharifying a lignocellulosic material with an effective amount of one or more cellulolyticmore » enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant; (b) fermenting the saccharified lignocellulosic material of step (a) with one or more fermentating microoganisms; and (c) recovering the organic substance from the fermentation.« less
USDA-ARS?s Scientific Manuscript database
Surfactants are commonly used in insecticide formulations as adjuvants to enhance the performance of the insecticidal active ingredients. However, surfactants may have their own intrinsic detrimental effect on insects. In this study, the responses of red imported fire ants, Solenopsis invicta Buren,...
Bardhan, Soumik; Kundu, Kaushik; Das, Sajal; Poddar, Madhumita; Saha, Swapan K; Paul, Bidyut K
2014-09-15
Modification of the interface by blending of surfactants produces considerable changes in the elastic rigidity of the interface, which in turn affects the physicochemical properties of w/o microemulsions. Hence, it could be possible to tune the thermodynamic properties, microstructures and antimicrobial activity of microemulsions by using ionic/non-ionic mixed surfactants and polar lipophilic oil, which are widely used in biologically relevant systems. The present report was aimed at precise characterization of mixed cetyltrimethylammonium bromide and polyoxyethylene (23) lauryl ether microemulsions stabilized in 1-pentanol (Pn) and isopropyl myristate at different physicochemical conditions by employing phase studies, the dilution method, conductivity, DLS, FTIR (with HOD probing) and (1)H NMR measurements. Further, microbiological activities at different compositions were examined against two bacterial strains Bacillus subtilis and Escherichia coli at 303 K. The formation of mixed surfactant microemulsions was found to be spontaneous at all compositions, whereas it was endothermic at equimolar composition. FTIR and (1)H NMR measurements showed the existence of bulk-like, bound and trapped water molecules in confined environments. Interestingly, composition dependence of both highest and lowest inhibitory effects was observed against the bacterial strains, whereas similar features in spontaneity of microemulsion formation were also evidenced. These results suggested a close relationship between thermodynamic stability and antimicrobial activities. Such studies on polar lipophilic oil derived mixed surfactant microemulsions have not been reported earlier. Copyright © 2014 Elsevier Inc. All rights reserved.
Lin, Xuliang; Qiu, Xueqing; Zhu, Duming; Li, Zihao; Zhan, Ningxin; Zheng, Jieyi; Lou, Hongming; Zhou, Mingsong; Yang, Dongjie
2015-10-01
Effect of the molecular structure of lignin-based polyoxyethylene ether (EHL-PEG) on enzymatic hydrolysis of Avicel and corn stover was investigated. With the increase of PEG contents and molecular weight of EHL-PEG, glucose yield of corn stover increased. EHL-PEG enhanced enzymatic hydrolysis of corn stover significantly at buffer pH 4.8-5.5. Glucose yield of corn stover at 20% solid content increased from 32.8% to 63.8% by adding EHL-PEG, while that with PEG4600 was 54.2%. Effect of EHL-PEG on enzymatic hydrolysis kinetics of cellulose film was studied by quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM). An enhancing mechanism of EHL-PEG on enzymatic hydrolysis kinetics of cellulose was proposed. Cellulase aggregates dispersed by EHL-PEG excavated extensive cavities into the surface of cellulose film, making the film become more loose and exposed. After the maximum enzymatic hydrolysis rate, the film was mainly peeled off layer by layer until equilibrium. Copyright © 2015 Elsevier Ltd. All rights reserved.
Microwave-Assisted Synthesis of Mesoporous Nano-Hydroxyapatite Using Surfactant Templates
Mesoporous nano-hydroxyapatite (n-HAP) was expeditiously synthesized using the pseudo sol-gel microwave-assisted protocol (30 min) in the presence of two novel templates, namely sodium lauryl ether sulfate (SLES) and linear alkylbenzenesulfonate (LABS). The cooperative self-assem...
21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.
Code of Federal Regulations, 2012 CFR
2012-04-01
... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...
21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.
Code of Federal Regulations, 2011 CFR
2011-04-01
... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...
21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.
Code of Federal Regulations, 2013 CFR
2013-04-01
... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...
21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.
Code of Federal Regulations, 2010 CFR
2010-04-01
... filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot.... Maintain the temperature of the contents of the flask at 150 °F for 2 hours using a hot plate while also...
Hoeman, Kurt W; Culbertson, Christopher T
2008-12-01
A new buffer has been developed for fast, high-efficiency separations of amino acids by MEKC. This buffer was more environmentally friendly than the most commonly used surfactant-containing buffers for MEKC separations. It used a commercially available dishwashing soap by Seventh Generation (Burlington, VT, USA), which contained three micelle-forming agents. The mixed micelles were composed of sodium lauryl ether sulfate (anionic), cocamidopropyl betaine (zwitterionic), and cocamide monoethanolamine (non-ionic). The optimized buffer contained 5.0% w/w Seventh Generation Free & Clear dishwashing soap, 10 mM sodium borate, and was completely void of organics. The lack of organics and the biodegradability of the surfactant molecules made this buffer more environmentally friendly than typical SDS-containing buffers. This new buffer also had a different selectivity and provided faster separations with higher separation efficiencies than SDS-based buffers. Fast separations of BODIPY FL labeled amino acids yielded peaks with separation efficiencies greater than 100,000 in less than 20 s.
Deng, Quanhua; Li, Haiping; Sun, Haoyang; Sun, Yange; Li, Ying
2016-05-01
The foam properties, such as the foamability, foam stability, drainage, coalescence and bulk rheology, of aqueous solutions containing an eco-friendly exopolysaccharide (EPS) secreted by a deep-sea mesophilic bacterium, Wangia profunda SM-A87, and an anionic surfactant, sodium fatty alcohol polyoxyethylene ether sulfate (AES), were studied. Both the foamability and foam stability of the EPS/AES solutions are considerably higher than those of single AES solutions, even at very low AES concentrations, although pure EPS solutions cannot foam. The improved foamability and foam stability arise from the formation of the EPS/AES complex via hydrogen bonds at the interfaces. The synergism between the EPS and AES decreases the surface tension, increases the interfacial elasticity and water-carrying capacity, and suppresses the coalescence and collapse of the foams. The EPS/AES foams are more salt-resistant than the AES foams. This work provides not only a new eco-friendly foam with great potential for use in enhanced oil recovery and health-care products but also useful guidance for designing other environmentally friendly foam systems that exhibit high performance. Copyright © 2016 Elsevier B.V. All rights reserved.
Decellularized Rat Lung Scaffolds Using Sodium Lauryl Ether Sulfate for Tissue Engineering.
Ma, Jinhui; Ju, Zhihai; Yu, Jie; Qiao, Yeru; Hou, Chenwei; Wang, Chen; Hei, Feilong
Perfusion decellularization with detergents is effective to maintain the architecture and proteins of extracellular matrix (ECM) for use in the field of lung tissue engineering (LTE). However, it is unclear which detergent is ideal to produce an acellular lung scaffold. In this study, we obtained two decellularized rat lung scaffolds using a novel detergent sodium lauryl ether sulfate (SLES) and a conventional detergent sodium dodecyl sulfate (SDS). Both decellularized lung scaffolds were assessed by histology, immunohistochemistry, scanning electron microscopy, DNA quantification, sulfated glycosaminoglycans (GAGs) quantification and western blot. Subsequently, the scaffolds were implanted subcutaneously in rats for 6 weeks and were evaluated via hematoxylin and eosin staining and Masson staining. Results indicated that SLES was effective to remove cells; moreover, lungs decellularized with SLES showed better preservation of sulfated GAGs, lung architecture, and ECM proteins than SDS. After 6 weeks, SLES scaffolds demonstrated a significantly greater potential for cell infiltration and blood vessel formation compared with SDS scaffolds. Taken together, we conclude that SLES is a promising detergent to produce an acellular scaffold using LTE for eventual transplantation.
Tang, Yongqiang; Liu, Zhang; Zhu, Linyi; Han, Yuchun; Wang, Yilin
2015-02-24
The aggregation behavior of anionic single-chain surfactant sodium lauryl ether sulfate containing three ether groups (SLE3S) with positively bicharged organic salt 1,2-bis(2-benzylammoniumethoxy)ethane dichloride (BEO) has been investigated in aqueous solution, and the effects of the BEO/SLE3S aggregate transitions on the fluorescent properties of anionic conjugated polyelectrolyte MPS-PPV with a larger molecular weight and cationic conjugated oligoelectrolyte DAB have been evaluated. Without BEO, SLE3S does not affect the fluorescent properties of MPS-PPV and only affects the fluorescent properties of DAB at a higher SLE3S concentration. With the addition of BEO, SLE3S and BEO form gemini-like surfactant (SLE3S)2-BEO. When the BEO/SLE3S molar ratio is fixed at 0.25, with increasing the BEO/SLE3S concentration, the BEO/SLE3S mixture forms large, loosely arranged aggregates and then transforms to closely packed spherical aggregates and finally to long thread-like micelles. The photoluminescence (PL) intensity of MPS-PPV varies with the morphologies of the BEO/SLE3S aggregates, while the PL intensity of DAB is almost independent of the aggregate morphologies. The results demonstrate that gemini-like surfactants formed through intermolecular interactions can effectively adjust the fluorescent properties of conjugated polyelectrolytes.
21 CFR 177.1970 - Vinyl chloride-lauryl vinyl ether copolymers.
Code of Federal Regulations, 2014 CFR
2014-04-01
... of the flask at 150 °F for 2 hours using a hot plate while also maintaining gentle mechanical agitation. Filter the contents of the flask rapidly through No. 42 Whatman filter paper with the aid of suction. Transfer the filtrate to flat glass dishes that are warmed on a hot plate and evaporate the...
Li, Jian; Ma, Li-Yun; Xu, Li; Shi, Zhi-Guo
2015-08-01
Benzophenone-type UV filters (BPs) are ubiquitous in the environment. Transformation products (TPs) of BPs with suspected toxicity are likely to be produced during disinfection of water by chlorination. To quickly predict the toxicity of TPs, in this study, a novel two-dimensional liquid-chromatography (2D-LC) method was established in which the objective of the first dimension was to separate the multiple components of the BPs sample after chlorination, using a reversed-phase liquid-chromatography mode. A biochromatographic system, i.e. bio-partitioning micellar chromatography with the polyoxyethylene (23) lauryl ether aqueous solution as the mobile phase, served as the second dimension to predict the toxicity of the fraction from the first dimension on the basis of the quantitative retention-activity relationships (QRARs) model. Six BPs, namely 2,4-dihydroxybenzophenone, oxybenzone, 4-hydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone and 2,2'-dihydroxy-4-methoxybenzophenone, were the target analytes subjected to chlorination. The products of these BPs after chlorination were directly injected to the 2D-LC system for analysis. The results indicated that most TPs may be less toxic than their parent chemicals, but some may be more toxic, and that intestinal toxicity of TPs may be more obvious than blood toxicity. The proposed method is time-saving, high-throughput, and reliable, and has great potential for predicting toxicity or bioactivity of unknown and/or known components in a complex sample. Graphical Abstract The scheme for the 2D-LC online prediction of toxicity of the transformation products of benzophenone-type UV filters after chlorination.
Surfactant-induced electroosmotic flow in microfluidic capillaries.
Azadi, Glareh; Tripathi, Anubhav
2012-07-01
Control of EOF in microfluidic devices is essential in applications such as protein/DNA sizing and high-throughput drug screening. With the growing popularity of poly(methyl methacrylate) (PMMA) as the substrate for polymeric-based microfludics, it is important to understand the effect of surfactants on EOF in these devices. In this article, we present an extensive investigation exploring changes in EOF rate induced by SDS, polyoxyethylene lauryl ether (Brij35) and CTAB in PMMA microfluidic capillaries. In a standard protein buffer (Tris-Glycine), PMMA capillaries exhibited a cathodic EOF with measured mobility of 1.54 ± 0.1 (× 10⁻⁴ cm²/V.s). In the presence of surfactant below a critical concentration, EOF was independent of surfactant concentration. At high concentrations of surfactants, the electroosmotic mobility was found to linearly increase/decrease as the logarithm of concentration before reaching a constant value. With SDS, the EOF increased by 257% (compared to buffer), while it was decreased by 238% with CTAB. In the case of Brij35, the electroosmotic mobility was reduced by 70%. In a binary surfactant system of SDS/CTAB and SDS/Brij35, addition of oppositely charged CTAB reduced the SDS-induced EOF more effectively compared to nonionic Brij35. We propose possible mechanisms that explain the observed changes in EOF and zeta potential values. Use of neutral polymer coatings in combination with SDS resulted in 50% reduction in the electroosmotic mobility with 0.1% hydroxypropyl methyl cellulose (HPMC), while including 2% poly (N,N-dimethylacrylamide) (PDMA) had no effect. These results will potentially contribute to the development of PMMA-based microfluidic devices. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Nonionic amphiphile nanoarchitectonics: self-assembly into micelles and lyotropic liquid crystals
NASA Astrophysics Data System (ADS)
Shrestha, Lok Kumar; Strzelczyk, Karolina Maria; Goswami Shrestha, Rekha; Ichikawa, Kotoko; Aramaki, Kenji; Hill, Jonathan P.; Ariga, Katsuhiko
2015-05-01
Amphiphiles, molecules that possess both hydrophilic and hydrophobic moieties, are architecturally simple molecules that can spontaneously self-assemble into complex hierarchical structures from lower to higher dimensions either in the bulk phase or at an interface. Recent developments in multifunctional nanostructure design using the advanced concept of nanoarchitectonics utilize this simple process of assembly. Amphiphilic self-assemblies involving lipids or proteins mimic the structure of biological systems, thus highlighting the necessity of a fundamental physical understanding of amphiphilic self-assembly towards a realization of the complex mechanisms operating in nature. Herein, we describe self-assembled microstructures of biocompatible and biodegradable tetraglycerol lauryl ether (C12G4) nonionic surfactant in an aqueous solvent system. Temperature-composition analyses of equilibrium phases identified by using small-angle x-ray scattering (SAXS) provide strong evidence of various spontaneously self-assembled mesostructures, such as normal micelles (Wm), hexagonal liquid crystal (H1), and reverse micelles (Om). In contrast to conventional poly(oxyethylene) nonionic surfactants, C12G4 did not exhibit the clouding phenomenon at higher temperatures (phase separation was not observed up to 100 °C), demonstrating the greater thermal stability of the self-assembled mesophases. Generalized indirect Fourier transformation (GIFT) evaluation of the SAXS data confirmed the formation of core-shell-type spherical micelles with a maximum dimension ca. 8.7 nm. The shape and size of the C12G4 micelles remained apparently unchanged over a wide range of concentrations (up to 20%), but intermicellar interactions increased and could be described by the Percus-Yevick (PY) theory (after Carnahan and Starling), which provides a very accurate analytical expression for the osmotic pressure of a monodisperse hard sphere.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Towata, Tomomi; Division of Hematopoiesis, Center for AIDS Research, Kumamoto University, 2-2-1 Honjo, Kumamoto 860-0811; Komizu, Yuji
Primary effusion lymphoma (PEL) is an aggressive neoplasm caused by human herpes virus-8 infection, and is generally resistant to chemotherapy. Hybrid liposomes, composed of dimyristoylphosphatidylcholine (DMPC) and polyoxyethylene (21) dodecyl ether (C{sub 12}(EO){sub 21}) (HL-21), were rapidly accumulated in the membrane of PEL cells. HL-21 also increased membrane fluidity of PEL cells, and induced caspase-3 activation along with cell death. These results suggest that HL-21 should be an effective and attractive regent for PEL treatment.
Huh, Yoon Ho; Park, Byoungchoo
2013-01-14
We herein report on the improved photovoltaic (PV) effects of using a polymer bulk-heterojunction (BHJ) layer that consists of a low-band gap electron donor polymer of poly(N-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)) (PCDTBT) and an acceptor of [6,6]-phenyl C₇₁ butyric acid methyl ester (PCBM₇₀), doped with an interface-engineering surfactant additive of poly(oxyethylene tridecyl ether) (PTE). The presence of an interface-engineering additive in the PV layer results in excellent performance; the addition of PTE to a PCDTBT:PCBM₇₀ system produces a power conversion efficiency (PCE) of 6.0%, which is much higher than that of a reference device without the additive (4.9%). We attribute this improvement to an increased charge carrier lifetime, which is likely to be the result of the presence of PTE molecules oriented at the interfaces between the BHJ PV layer and the anode and cathode, as well as at the interfaces between the phase-separated BHJ domains. Our results suggest that the incorporation of the PTE interface-engineering additive in the PCDTBT:PCBM₇₀ PV layer results in a functional composite system that shows considerable promise for use in efficient polymer BHJ PV cells.
Nandy, Debdurlav; Mitra, Rajib K; Paul, Bidyut K
2007-06-01
The phase diagrams of the pseudo-quaternary systems poly(oxyethylene) (10) stearyl ether (Brij-76)/1-butanol/isooctane/water (with equal amounts of oil and water in the presence of two nonaqueous polar solvents (NPS), ethylene glycol (EG), and tetraethylene glycol (TEG)), have been constructed at 30 degrees C. Regular fish-tail diagrams were obtained up to psi (weight fraction of EG or TEG in the mixture of polar solvents) equal to 0.5, confirming the establishment of hydrophile-lipophile balance (HLB) of the systems. The maximum solubilization capacity passed through a minimum at psi=0.2. No HLB was obtained at higher psi. The usual fish-tail diagrams were also obtained in temperature-induced phase mapping at fixed W(1) (weight fraction of 1-butanol in total amphiphile). Solubilization capacity and HLB temperature (T(HLB)) decreased with increasing psi at a fixed W(1), the effect being more pronounced for TEG than EG. A correlation between HLB temperature (T(HLB)) and HLB number (N(HLB)) of mixed amphiphiles (Brij-76+Bu) in pseudo-quaternary systems (in the presence of water and partial substitution of water with both NPS) has been established. The novelty of the work with respect to possible applications has been discussed.
Vleugels, Leo F W; Pollet, Jennifer; Tuinier, Remco
2015-05-21
Polyelectrolyte-surfactant complexes (PESC) are a class of materials which form spontaneously by self-assembly driven by electrostatic and hydrophobic interactions. PESC containing sodium lauryl ether sulfates (SLES) have found wide application in hair care products like shampoo. Typically, SLES with only one or two ethylene oxide (EO) groups are used for this application. We have studied the influence of the size of the EO block (ranging from 0 to 30 EO groups) on complexation with two model polycations: linear polyDADMAC and branched PEI. PESC size and electrostatic properties were determined during stepwise titration of buffered polycation solutions. The critical aggregation concentration (CAC) of PESC was determined by surface tension measurements and fluorescence spectroscopy. For polyDADMAC, there is no influence of the size of the EO block on the complexation behavior; the stiff polycation governs the structure formation. For PEI, it was seen that the EO block size does affect the structure of the complexes. The CAC value of the investigated complexes turns out to be rather independent of the EO block size; however, the CMC/CAC ratio decreases with increasing size of the EO block. This latter observation explains why the Lochhead-Goddard effect is most effective for small EO blocks.
Masoum, Saeed; Gholami, Ali; Ghaheri, Salehe; Bouveresse, Delphine Jouan-Rimbaud; Cordella, Christophe B Y; Rutledge, Douglas N
2016-07-01
A new composite coating of polypyrrole and sodium lauryl ether sulfate was electrochemically prepared on a stainless-steel wire using cyclic voltammetry. The application and performance of the fiber was evaluated for the headspace solid-phase microextraction of a fragrance in aqueous bleach samples followed by gas chromatography combined with mass spectrometry to assess the fragrance stability in this kind of household cleaning product. To obtain a stable and efficient composite coating, parameters related to the coating process such as scan rate and numbers of cycles were optimized using a central composite design. In addition, the effects of various parameters on the extraction efficiency of the headspace solid-phase microextraction process such as extraction temperature and time, ionic strength, sample volume, and stirring rate were investigated by experimental design methods using Plackett-Burman and Doehlert designs. The optimum values of 53°C and 28 min for sample temperature and time, respectively, were found through response surface methodology. Results show that the combination of polypyrrole and sodium lauryl ether sulfate in a composite form presents desirable opportunities to produce new materials to study fragrance stability by headspace solid-phase microextraction. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Citral degradation in micellar structures formed with polyoxyethylene-type surfactants.
Park, Sung Joon; Hong, Chi Rac; Choi, Seung Jun
2015-03-01
In a micellar solution, the chemical degradation of poorly water-soluble food flavours can be influenced by the properties of the surfactants forming the micelles in aqueous solutions. To evaluate how hydrophilic head size and hydrophobic tail length influence the chemical degradation rate of food flavour, micelles were prepared with Brij surfactants (Brij 35, 58, 78 and 700), each of which had very similar molecular structures (polyoxyethylene fatty acid ether). The chemical degradation of citral in Brij micelles was found to be highest in an acidic environment. There was no significant difference in the chemical degradation rate of citral in Brij micelles in non-acidic conditions, regardless of the hydrophilic head size or hydrophobic tail length. Brij surfactants with larger hydrophilic heads effectively retarded the chemical degradation of citral in an acidic environment. Our findings suggest that the length of the hydrophobic tail rarely influenced the micelle's ability to chemically stabilize citral. Copyright © 2014 Elsevier Ltd. All rights reserved.
Palmgren, M G; Sommarin, M; Ulvskov, P; Larsson, C
1990-01-29
In search for a detergent to be used to assess the sidedness of plant plasma membrane vesicles by enzyme latency we tested the effect of 42 detergents on the ATPase activity of right-side-out and inside-out plasma membrane vesicles from sugar beet leaves. Most of the detergents seemed to inactivate the ATPase in addition to disrupting the permeability barrier to ATP. There were two main exceptions, namely long chain polyoxyethylene acyl ethers, such as detergents of the Brij series and Lubrol WX, and long chain lysophospholipids. These two types of detergents permeabilized the membranes at low concentrations and did not inhibit the ATPase at higher concentrations. Unmasking of latent active sites seemed to explain the activation of the plasma membrane H(+)-ATPase produced by long chain polyoxyethylene acyl ethers. These detergents should therefore be ideal for determination of vesicle orientation based on ATPase latency. By contrast, long chain lysophospholipids were found to be highly specific activators of the enzyme. In addition, long chain fatty acids were found to strongly inhibit ATP-dependent proton accumulation in the vesicles without inhibiting ATP hydrolysis. This uncoupling effect of the fatty acids could be abolished by the addition of fatty acid-free bovine serum albumin (BSA). Similarly, the proton transport capacity of ageing vesicles could be restored by addition of BSA. The latter findings may explain why isolated plasma membranes so often exhibit increased permeability to protons on ageing.
Ito, Toshifumi; Tsuji, Yukitaka; Aramaki, Kenji; Tonooka, Noriaki
2012-01-01
Multiple emulsions, also called complex emulsions or multiphase emulsions, include water-in-oil-in-water (W/O/W)-type and oil-in-water-in-oil (O/W/O)-type emulsions. W/O/W-type multiple emulsions, obtained by utilizing lamellar liquid crystal with a layer structure showing optical anisotropy at the periphery of emulsion droplets, are superior in stability to O/W/O-type emulsions. In this study, we investigated a two-step emulsification process for a W/O/W-type multiple emulsion utilizing liquid crystal emulsification. We found that a W/O/W-type multiple emulsion containing lamellar liquid crystal can be prepared by mixing a W/O-type emulsion (prepared by primary emulsification) with a lamellar liquid crystal obtained from poly(oxyethylene) stearyl ether, cetyl alcohol, and water, and by dispersing and emulsifying the mixture in an outer aqueous phase. When poly(oxyethylene) stearyl ether and cetyl alcohol are each used in a given amount and the amount of water added is varied from 0 to 15 g (total amount of emulsion, 100 g), a W/O/W-type multiple emulsion is efficiently prepared. When the W/O/W-type multiple emulsion was held in a thermostatic bath at 25°C, the droplet size distribution showed no change 0, 30, or 60 days after preparation. Moreover, the W/O/W-type multiple emulsion strongly encapsulated Uranine in the inner aqueous phase as compared with emulsions prepared by one-step emulsification.
Sodium lauryl ether sulfate (SLES) degradation by nitrate-reducing bacteria.
Paulo, Ana M S; Aydin, Rozelin; Dimitrov, Mauricio R; Vreeling, Harm; Cavaleiro, Ana J; García-Encina, Pedro A; Stams, Alfons J M; Plugge, Caroline M
2017-06-01
The surfactant sodium lauryl ether sulfate (SLES) is widely used in the composition of detergents and frequently ends up in wastewater treatment plants (WWTPs). While aerobic SLES degradation is well studied, little is known about the fate of this compound in anoxic environments, such as denitrification tanks of WWTPs, nor about the bacteria involved in the anoxic biodegradation. Here, we used SLES as sole carbon and energy source, at concentrations ranging from 50 to 1000 mg L -1 , to enrich and isolate nitrate-reducing bacteria from activated sludge of a WWTP with the anaerobic-anoxic-oxic (A 2 /O) concept. In the 50 mg L -1 enrichment, Comamonas (50%), Pseudomonas (24%), and Alicycliphilus (12%) were present at higher relative abundance, while Pseudomonas (53%) became dominant in the 1000 mg L -1 enrichment. Aeromonas hydrophila strain S7, Pseudomonas stutzeri strain S8, and Pseudomonas nitroreducens strain S11 were isolated from the enriched cultures. Under denitrifying conditions, strains S8 and S11 degraded 500 mg L -1 SLES in less than 1 day, while strain S7 required more than 6 days. Strains S8 and S11 also showed a remarkable resistance to SLES, being able to grow and reduce nitrate with SLES concentrations up to 40 g L -1 . Strain S11 turned out to be the best anoxic SLES degrader, degrading up to 41% of 500 mg L -1 . The comparison between SLES anoxic and oxic degradation by strain S11 revealed differences in SLES cleavage, degradation, and sulfate accumulation; both ester and ether cleavage were probably employed in SLES anoxic degradation by strain S11.
Physicochemical studies of mixed surfactant microemulsions with isopropyl myristate as oil.
Bardhan, Soumik; Kundu, Kaushik; Saha, Swapan K; Paul, Bidyut K
2013-07-15
The present study is focused on evaluation of interfacial compositions and thermodynamic properties of w/o mixed surfactant [(sodium dodecylsulfate, SDS/polyoxyethylene (23) lauryl ether, Brij-35)/1-pentanol (Pn)/isopropyl myristate (IPM)] microemulsions under various physicochemical conditions by the dilution method. The number of moles of Pn at the interface (n(a)(i)) and bulk oil (n(a)(o)), and various thermodynamic parameters [viz. standard Gibbs free energy (ΔG(o→i)(0)), standard enthalpy (ΔH(o→i)(0)), and standard entropy (ΔS(o→i)(0)) of the transfer of Pn from bulk oil to the interface] have been found to be dependent on the molar ratio of water to surfactant (ω), concentration of Brij-35 (X(Brij-35)), and temperature. Temperature-insensitive microemulsions with zero specific heat capacity (ΔC(p)(0))(o→i) have been formed at specific compositions. The intrinsic enthalpy change of the transfer process (ΔH(0))(o→i)* has been evaluated from linear correlation between ΔH(o→i)(0) and ΔS(o→i)(0) at different experimental temperatures. The present report also aims at a precise characterization on the basis of molecular interactions between the constituents and provides insight into the nature of the oil/water interfaces of these systems by conductivity and dynamic light scattering studies as a function of ω and X(Brij-35). Conductivity studies reveal that incorporation of Brij-35 in non-percolating water/SDS/Pn/IPM systems makes them favorable for ω-induced percolation behavior up to X(Brij-35) ≤ 0.5. But further addition of Brij-35 causes a decrease in conductivity with increasing ω. Furthermore, the hydrodynamic diameters of the microemulsion droplets increase with increase in both X(Brij-35) and ω. Correlations of the results in terms of the evaluated physicochemical parameters have been attempted. Copyright © 2013 Elsevier Inc. All rights reserved.
Synthesis of nanocrystalline CeO{sub 2} particles by different emulsion methods
DOE Office of Scientific and Technical Information (OSTI.GOV)
Supakanapitak, Sunisa; Boonamnuayvitaya, Virote; Jarudilokkul, Somnuk, E-mail: somnuk.jar@kmutt.ac.th
2012-05-15
Cerium oxide nanoparticles were synthesized using three different methods of emulsion: (1) reversed micelle (RM); (2) emulsion liquid membrane (ELM); and (3) colloidal emulsion aphrons (CEAs). Ammonium cerium nitrate and polyoxyethylene-4-lauryl ether (PE4LE) were used as cerium and surfactant sources in this study. The powder was calcined at 500 Degree-Sign C to obtain CeO{sub 2}. The effect of the preparation procedure on the particle size, surface area, and the morphology of the prepared powders were investigated. The obtained powders are highly crystalline, and nearly spherical in shape. The average particle size and the specific surface area of the powders frommore » the three methods were in the range of 4-10 nm and 5.32-145.73 m{sup 2}/g, respectively. The CeO{sub 2} powders synthesized by the CEAs are the smallest average particle size, and the highest surface area. Finally, the CeO{sub 2} prepared by the CEAs using different cerium sources and surfactant types were studied. It was found that the surface tensions of cerium solution and the type of surfactant affect the particle size of CeO{sub 2}. - Graphical Abstract: The emulsion droplet size distribution and the TEM images of CeO{sub 2} prepared by different methods: reversed micelle (RM), emulsion liquid membrane (ELM) and colloidal emulsion aphrons (CEAs). Highlights: Black-Right-Pointing-Pointer Nano-sized CeO{sub 2} was successfully prepared by three different emulsion methods. Black-Right-Pointing-Pointer The colloidal emulsion aphrons method producing CeO{sub 2} with the highest surface area. Black-Right-Pointing-Pointer The surface tensions of a cerium solution have slightly effect on the particle size. Black-Right-Pointing-Pointer The size control could be interpreted in terms of the adsorption of the surfactant.« less
Karakucuk, Alptug; Celebi, Nevin; Teksin, Zeynep Safak
2016-12-01
The objective of this study was to prepare ritonavir (RTV) nanosuspensions, an anti-HIV protease inhibitor, to solve its poor water solubility issues. The microfluidization method with a pre-treatment step was used to obtain the nanosuspensions. Design of Experiment (DoE) approach was performed in order to understand the effect of the critical formulation parameters which were selected as polymer type (HPMC or PVP), RTV to polymer ratio, and number of passes. Interactions between the formulation variables were evaluated according to Univariate ANOVA. Particle size, particle size distribution and zeta potential were selected as dependent variables. Scanning electron microscopy, X-ray powder diffraction, and differential scanning calorimetry were performed for the in vitro characterization after lyophilization of the optimum nanosuspension formulation. The saturation solubility was examined in comparison with coarse powder, physical mixture and nanosuspension. In vitro dissolution studies were conducted using polyoxyethylene 10 lauryl ether (POE10LE) and biorelevant media (FaSSIF and FeSSIF). The results showed nanosuspensions were partially amorphous and spherically shaped with particle sizes ranging from 400 to 600nm. Moreover, 0.1-0.4 particle size distribution and about -20mV zeta potential values were obtained. The nanosuspension showed a significantly increased solubility when compared to coarse powder (3.5 fold). Coarse powder, physical mixture, nanosuspension and commercial product dissolved completely in POE10LE; however, cumulative dissolved values reached ~20% in FaSSIF for the commercial product and nanosuspension. The nanosuspension showed more than 90% drug dissolved in FeSSIF compared to the commercial product which showed ~50% in the same medium. It was determined that RTV dissolution was increased by nanosuspension formulation. We concluded that DoE approach is useful to develop nanosuspension formulation to improve solubility and dissolution rate of RTV. Copyright © 2016 Elsevier B.V. All rights reserved.
Valerio, M; Diolez, P; Haraux, F
1993-09-01
ATP hydrolysis, triggered by the addition of polyoxyethylene-9-lauryl ether (Lubrol) or lauryldimethylamine oxide (LDAO) to energized plant mitochondria was studied in some details. The membrane disruption was quasi-instantaneous (2-3 s) with both detergents, as shown by the decrease of turbidity and the stopping of respiration. In pea leaf mitochondria, Lubrol triggered ATP hydrolysis in almost the same way as valinomycin plus nigericin, except that the activity was slightly stimulated and became insensitive to carboxyatractyloside. This allowed investigations of ATP hydrolysis without any interference of the ATP/ADP antiporter or the phosphate carrier. Lubrol did not prevent the ATPase from deactivating in pea leaf mitochondria, and did not trigger any ATP hydrolysis in potato tuber mitochondria. At variance with Lubrol, LDAO changed the properties of the F0F1 ATPase. It made the enzyme oligomycin insensitive and froze it in an activated state. The activity was also 5-8-times stimulated in pea leaf mitochondria. Moreover, LDAO revealed an important ATP hydrolase activity when added to energized potato tuber mitochondria. Despite the specific effect of LDAO, the activity triggered by this detergent strongly depended on the energized state of the organelles before detergent addition. From this study, it is concluded that the electrochemical proton gradient is completely necessary to activate the F0F1-ATPase in intact plant mitochondria, as known in chloroplasts and suggested by some reports in animal mitochondria. Moreover, it is suggested that the main difference between the enzymes of pea leaf and potato tuber mitochondria is their rate of deactivation after the collapse of the transmembrane electrochemical potential difference. Finally, when properly used, detergents appear to be a powerful tool to probe the state of the ATPase in intact mitochondria, and maybe in more integrated systems.
Wallgren, Marcus; Lidman, Martin; Pedersen, Anders; Brännström, Kristoffer; Karlsson, B Göran; Gröbner, Gerhard
2013-01-01
The anti-apoptotic B-cell CLL/lymphoma-2 (Bcl-2) protein and its counterpart, the pro-apoptotic Bcl-2-associated X protein (Bax), are key players in the regulation of the mitochondrial pathway of apoptosis. However, how they interact at the mitochondrial outer membrane (MOM) and there determine whether the cell will live or be sentenced to death remains unknown. Competing models have been presented that describe how Bcl-2 inhibits the cell-killing activity of Bax, which is common in treatment-resistant tumors where Bcl-2 is overexpressed. Some studies suggest that Bcl-2 binds directly to and sequesters Bax, while others suggest an indirect process whereby Bcl-2 blocks BH3-only proteins and prevents them from activating Bax. Here we present the results of a biophysical study in which we investigated the putative interaction of solubilized full-length human Bcl-2 with Bax and the scope for incorporating the former into a native-like lipid environment. Far-UV circular dichroism (CD) spectroscopy was used to detect direct Bcl-2-Bax-interactions in the presence of polyoxyethylene-(23)-lauryl-ether (Brij-35) detergent at a level below its critical micelle concentration (CMC). Additional surface plasmon resonance (SPR) measurements confirmed this observation and revealed a high affinity between the Bax and Bcl-2 proteins. Upon formation of this protein-protein complex, Bax also prevented the binding of antimycin A2 (a known inhibitory ligand of Bcl-2) to the Bcl-2 protein, as fluorescence spectroscopy experiments showed. In addition, Bcl-2 was able to form mixed micelles with Triton X-100 solubilized neutral phospholipids in the presence of high concentrations of Brij-35 (above its CMC). Following detergent removal, the integral membrane protein was found to have been fully reconstituted into a native-like membrane environment, as confirmed by ultracentrifugation and subsequent SDS-PAGE experiments.
Hou, Mengna; Dang, Leping; Liu, Tiankuo; Guo, Yun; Wang, Zhanzhong
2017-08-09
Nanoscale microemulsions have been utilized as delivery carriers for nutraceuticals and active biological drugs. Herein, we designed and synthesized a novel oil in water (O/W) fluorescent microemulsion based on isoamyl acetate, polyoxyethylene castor oil EL (CrEL), and water. The microemulsion emitted bright blue fluorescence, thus exhibiting its potential for active drug detection with label-free strategy. The microemulsion exhibited excitation-dependent emission and distinct red shift with longer excitation wavelengths. Lifetime and quantum yield of fluorescent microemulsion were 2.831 ns and 5.0%, respectively. An excellent fluorescent stability of the microemulsion was confirmed by altering pH, ionic strength, temperature, and time. Moreover, we proposed a probable mechanism of fluorochromic phenomenon, in connection with the aromatic ring structure of polyoxyethylene ether substituent in CrEL. Based on our findings, we concluded that this new fluorescent microemulsion is a promising drug carrier that can facilitate active drug detection with a label-free strategy. Although further research is required to understand the exact mechanism behind its fluorescence property, this work provided valuable guidance to develop new biosensors based on fluorescent microemulsion.
Synthesis of Eugenol–Lauryl Methacrylate Copolymers via Cationic Polymerization
NASA Astrophysics Data System (ADS)
Fajrin, A.; Marliana, SD; Handayani, D. S.
2018-04-01
Eugenol is one of the most abundant natural resources in Indonesia. The recently bio-based polymer resin is created based on eugenol because eugenol is functionalized with the polymerizable group. In order to improve the functional properties of eugenol, in this research Eugenol–Lauryl Methacrylate copolymers (co-poly(Eg-LMA)) were synthesized by cationic polymerization using H2SO4 as an initiator under the nitrogen atmosphere. Structure identification of the copolymer showed the absorption of the vinyl group from the monomers disappear at the analysis through FTIR at the wave number 1637-1639 and 985-995 cm-1 and also 1H-NMR on the chemical shift 5,97 and 5,08 ppm. The resulting copolymers obtained brown powder in 32.03 % yieldsand melting point at 96 – 97 °C. Solubility test of the co-poly(Eg-LMA) showed that the polymer couldnot soluble in water but soluble in chloroform, diethyl ether, and benzene. Average molecular weight of co-poly(Eg-LMA) Led Ostwald viscometry was obtained 42020 with the degree of polymerization by 200.
Study on property and stability mechanism of LAB-AEO-4 system
NASA Astrophysics Data System (ADS)
Song, Kaifei; Ge, Jijiang; Wang, Yang; Zhang, Guicai; Jiang, Ping
2017-04-01
The behaviors of binary blending systems of fatty alcohol polyoxyethylene ether (AEO-4) blended with the laurel amide betaine (LAB) was investigated at 80°C,the results indicated that the optimal ratio of the mixed system of LAB-AEO-4 was 5:2. The stability mechanism of LAB-AEO-4 system was analyzed from three aspects of dynamic surface tension,gas permeation rate and surface rheology.The results showed that the tension of mixed system was easier to achieve balance,the constant of gas permeation rate of the mixed system decreased by about 7% and the elastic modulus and dilational modulus increased by about 2 times compared with the single LAB system.
Barra Caracciolo, Anna; Cardoni, Martina; Pescatore, Tanita; Patrolecco, Luisa
2017-07-01
The anionic surfactant sodium lauryl ether sulphate (SLES) is the main component of most commercial products used for soil conditioning in the excavation industry, in particular as lubricants for mechanized tunnelling. Its use during the excavation processes can result in either the subsequent possible re-use of the huge amount of soil debris as by-products (e.g. land covering) or its discharge as waste. Currently, there are neither SLES soil threshold limits in European legislation, nor comprehensive studies on the environmental risk for soil ecosystems in these exposure scenarios. In this context, the present paper reviews the available data on the intrinsic characteristics of persistence and the ecotoxicological effects of the anionic surfactant SLES. Although SLES is generally reported to be biodegradable in standard tests, with degradation rates between 7 h and 30 days, depending on the initial conditions, data on its biodegradation in environmental studies are quite scarce. Consequently, assessing SLES biodegradation rates in field conditions is crucial for evaluating if in residual concentrations (typically in the range 40-500 mg/kg in excavated soils) it can or not be a potential hazard for terrestrial and water organisms. Laboratory ecotoxicological tests pointed out detrimental effects of SLES for aquatic organisms, while data on the terrestrial species are rather poor so far and further studies at the expected environmental concentrations are necessary. Finally, the review reports the main analytical methods available for detecting anionic surfactants in solid matrices and the future research needed to improve knowledge on the possible environmental risks posed by the use of SLES in foaming agents for mechanized tunnelling. Copyright © 2017 Elsevier Ltd. All rights reserved.
Code of Federal Regulations, 2010 CFR
2010-07-01
... polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct. 721.3800 Section 721.3800... Formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct. (a... generically as formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene...
Lavergne, Aurélie; Zhu, Ying; Pizzino, Aldo; Molinier, Valérie; Aubry, Jean-Marie
2011-08-15
Two agro-based anionic surfactants containing an isosorbide moiety have been synthesized and their amphiphilic properties evaluated. Since isosorbide is now considered as an important platform chemical of the starch industry, these compounds could represent bio-sourced alternatives to the alkyl ether sulfates (notably lauryl ether sulfate, LES) that are based on petroleum-derived ethylene oxides. As isosorbide is an asymmetric diol, two isomers can be prepared (2-O-dodecyl isosorbide sulfate and 5-O-dodecyl isosorbide sulfate) that show significantly different aqueous properties as regards to their Krafft temperatures and critical micellar concentrations. 5-O-dodecyl isosorbide sulfate is the most soluble and the most efficient surfactant. It possesses a much lower critical micelle concentration (cmc) than sodium dodecyl sulfate, SDS, leading to comparable foaming properties with a three times lower concentration. Its behavior compares well with the one of pure diethoxylated dodecyl sulfate that has also been prepared and evaluated in this work. Copyright © 2011 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Lunter, Dominique; Daniels, Rolf
2016-03-01
Confocal Raman microscopy has become an advancing technique in the characterization of drug transport into the skin. In this study the skin penetration of a local anesthetic from a semisolid preparation was investigated. Furthermore, the effect of the chemical enhancers propylene glycol and POE-23-lauryl ether on its penetration was investigated. The results show that confocal Raman microscopy may provide detailed information on the penetration of APIs into the skin and may elucidate their distribution within the skin with high resolution. The results of the CRM analysis are fully in line with those of conventional permeation and penetration experiments.
A novel kind of concrete superplasticizer based on aryl isocyanate polycondensates
NASA Astrophysics Data System (ADS)
Ding, Bei; Qian, Shanshan; Qiu, Ying; Wang, Yi; Zheng, Chunyang; Wang, Gaoming
2017-03-01
A novel superplasticizer was synthesized by polycondensation of Alkyl phenol phosphate and toluene diisocyanate grafting with methoxy polyoxyethylene ether (MPEG). The chemical structure and molecular weight of polycondensates molecules were determined by 1H nuclear magnetic resonance (NMR) and gel permeation chromatography respectively. The experimental results indicated that the polycondensates of Alkyl phenol phosphate and toluene diisocyanate grafting with MPEG not only exhibited good water-reducing properties but also demonstrated effective anti-clay abilities alone. Furthermore, the polycondensates showed good fluidity maintaining abilities within 1-3 h and good workability of concrete. The results of T500 Time experiments show that lower plastic viscosity of the polycondensates leads to fresh concrete much “looser” than conventional PCEs in self-compacting concrete.
Magnetically induced orientation of mesochannels in mesoporous silica films at 30 tesla.
Yamauchi, Yusuke; Sawada, Makoto; Komatsu, Masaki; Sugiyama, Atsushi; Osaka, Tetsuya; Hirota, Noriyuki; Sakka, Yoshio; Kuroda, Kazuyuki
2007-12-03
We demonstrate the magnetically induced orientation of mesochannels in mesoporous silica films prepared with low-molecular-weight surfactants under an extremely high magnetic field of 30 T. This process is principally applicable to any type of surfactant that has magnetic anisotropy because such a high magnetic field provides sufficient magnetic energy for smooth magnetic orientation. Hexadecyltrimethylammonium bromide (CTAB) and polyoxyethylene-10-cetyl ether (Brij 56) were used as cationic and nonionic surfactants, respectively. According to XRD and cross-sectional TEM, mesochannels aligned perpendicular to the substrates were observed in films prepared with low-molecular-weight surfactants, although the effect was incomplete. The evolution of these types of films should lead to future applications such as highly sensitive chemical sensors and selective separation.
Park, Sin Young; Cheong, Won Jo
2015-09-01
This study introduces a preparation method for polymer-encased monolith frits with improved durability for liquid chromatography columns. The inner surface of the polyether ether ketone tubing is pretreated with sulfuric acid in the presence of catalysts (vanadium oxide and sodium sulfate). The tubing was rinsed with water and acetone, flushed with nitrogen, and treated with glycidyl methacrylate. After washing, the monolith reaction mixture composed of lauryl methacrylate, ethylene glycol dimethacrylate, initiator, and porogenic solvent was filled in the tubing and subjected to in situ polymerization. The tubing was cut into thin slices and used as frits for microcolumns. To check their durability, the frit slices were placed in a vial and a heavy impact was applied on the vial by a vortex mixer for various periods. The frits made in the presence of catalysts were found to be more durable than those made without catalysts. Furthermore, when the monolith-incorporated tubing was used as a chromatography column, the column prepared in the presence of catalysts resulted in a better separation efficiency. The separation performance of the columns installed with the polyether ether ketone encased monolith frits was comparable to that of the columns installed with the commercial stainless-steel screen frits. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Effects of surfactants on the properties of mortar containing styrene/methacrylate superplasticizer.
Negim, El-Sayed; Kozhamzharova, Latipa; Khatib, Jamal; Bekbayeva, Lyazzat; Williams, Craig
2014-01-01
The physical and mechanical properties of mortar containing synthetic cosurfactants as air entraining agent are investigated. The cosurfactants consist of a combination of 2% dodecyl benzene sodium sulfonate (DBSS) and either 1.5% polyvinyl alcohol (PVA) or 1.5% polyoxyethylene glycol monomethyl ether (POE). Also these cosurfactants were used to prepare copolymers latex: styrene/butyl methacrylate (St/BuMA), styrene/methyl methacrylate (St/MMA), and styrene/glycidyl methacrylate (St/GMA), in order to study their effects on the properties of mortar. The properties of mortar examined included flow table, W/C ratio, setting time, water absorption, compressive strength, and combined water. The results indicate that the latex causes improvement in mortar properties compared with cosurfactants. Also polymer latex containing DBSS/POE is more effective than that containing DBSS/PVA.
Effects of Surfactants on the Properties of Mortar Containing Styrene/Methacrylate Superplasticizer
Negim, El-Sayed; Kozhamzharova, Latipa; Khatib, Jamal; Bekbayeva, Lyazzat; Williams, Craig
2014-01-01
The physical and mechanical properties of mortar containing synthetic cosurfactants as air entraining agent are investigated. The cosurfactants consist of a combination of 2% dodecyl benzene sodium sulfonate (DBSS) and either 1.5% polyvinyl alcohol (PVA) or 1.5% polyoxyethylene glycol monomethyl ether (POE). Also these cosurfactants were used to prepare copolymers latex: styrene/butyl methacrylate (St/BuMA), styrene/methyl methacrylate (St/MMA), and styrene/glycidyl methacrylate (St/GMA), in order to study their effects on the properties of mortar. The properties of mortar examined included flow table, W/C ratio, setting time, water absorption, compressive strength, and combined water. The results indicate that the latex causes improvement in mortar properties compared with cosurfactants. Also polymer latex containing DBSS/POE is more effective than that containing DBSS/PVA. PMID:24955426
Serna-Galvis, Efraim A; Silva-Agredo, Javier; Giraldo, Ana L; Flórez-Acosta, Oscar A; Torres-Palma, Ricardo A
2016-01-15
Synthetic pharmaceutical effluents loaded with the β-lactam antibiotic oxacillin were treated using advanced oxidation processes (the photo-Fenton system and TiO2 photocatalysis) and chloride mediated electrochemical oxidation (with Ti/IrO2 anodes). Combinations of the antibiotic with excipients (mannitol or tartaric acid), an active ingredient (calcium carbonate, i.e. bicarbonate ions due to the pH) and a cleaning agent (sodium lauryl ether sulfate) were considered. Additionally, urban wastewater that had undergone biological treatment was doped with oxacillin and treated with the tested systems. The evolution of antimicrobial activity was monitored as a parameter of processes efficiency. Although the two advanced oxidation processes (AOPs) differ only in the way they produce OH, marked differences were observed between them. There were also differences between the AOPs and the electrochemical system. Interestingly, each additive had a different effect on each treatment. For water loaded with mannitol, electrochemical treatment was the most suitable option because the additive did not significantly affect the efficiency of the system. Due to the formation of a complex with Fe(3+), tartaric acid accelerated the elimination of antibiotic activity during the photo-Fenton process. For TiO2 photocatalysis, the presence of bicarbonate ions contributed to antibiotic activity elimination through the possible formation of carbonate and bicarbonate radicals. Sodium lauryl ether sulfate negatively affected all of the processes. However, due to the higher selectivity of HOCl compared with OH, electrochemical oxidation showed the least inhibited efficiency. For the urban wastewater doped with oxacillin, TiO2 photocatalysis was the most efficient process. These results will help select the most suitable technology for the treatment of water polluted with β-lactam antibiotics. Copyright © 2015 Elsevier B.V. All rights reserved.
21 CFR 172.822 - Sodium lauryl sulfate.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium lauryl sulfate. 172.822 Section 172.822... CONSUMPTION Multipurpose Additives § 172.822 Sodium lauryl sulfate. The food additive sodium lauryl sulfate... following specifications: (1) It is a mixture of sodium alkyl sulfates consisting chiefly of sodium lauryl...
21 CFR 573.820 - Polyoxyethylene glycol (400) mono- and dioleates.
Code of Federal Regulations, 2011 CFR
2011-04-01
... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.820 Polyoxyethylene glycol (400) mono- and dioleates. The food additive polyoxyethylene glycol (400) mono- and dioleates may be safely used as an emulsifier...
21 CFR 573.820 - Polyoxyethylene glycol (400) mono- and dioleates.
Code of Federal Regulations, 2014 CFR
2014-04-01
... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.820 Polyoxyethylene glycol (400) mono- and dioleates. The food additive polyoxyethylene glycol (400) mono- and dioleates may be safely used as an emulsifier...
21 CFR 573.820 - Polyoxyethylene glycol (400) mono- and dioleates.
Code of Federal Regulations, 2013 CFR
2013-04-01
... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.820 Polyoxyethylene glycol (400) mono- and dioleates. The food additive polyoxyethylene glycol (400) mono- and dioleates may be safely used as an emulsifier...
21 CFR 573.820 - Polyoxyethylene glycol (400) mono- and dioleates.
Code of Federal Regulations, 2010 CFR
2010-04-01
... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.820 Polyoxyethylene glycol (400) mono- and dioleates. The food additive polyoxyethylene glycol (400) mono- and dioleates may be safely used as an emulsifier...
21 CFR 573.820 - Polyoxyethylene glycol (400) mono- and dioleates.
Code of Federal Regulations, 2012 CFR
2012-04-01
... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.820 Polyoxyethylene glycol (400) mono- and dioleates. The food additive polyoxyethylene glycol (400) mono- and dioleates may be safely used as an emulsifier...
Safety Assessment of Alkyl PEG Sulfosuccinates as Used in Cosmetics.
Johnson, Wilbur; Heldreth, Bart; Bergfeld, Wilma F; Belsito, Donald V; Hill, Ronald A; Klaassen, Curtis D; Liebler, Daniel C; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Andersen, F Alan
2015-09-01
The Cosmetic Ingredient Review (CIR) Expert Panel (Panel) reviewed the safety of alkyl polyethylene glycol (PEG) sulfosuccinates, which function in cosmetics mostly as surfactants/cleansing agents. Although these ingredients may cause ocular and skin irritation, dermal penetration is unlikely because of the substantial polarity and molecular size of these ingredients. The Panel considered the negative oral carcinogenicity and reproductive and developmental toxicity data on chemically related laureths (PEG lauryl ethers) and negative repeated dose toxicity and skin sensitization data on disodium laureth sulfosuccinate supported the safety of these alkyl PEG sulfosuccinates in cosmetic products, but. The CIR Expert Panel concluded that the alkyl PEG sulfosuccinates are safe in the present practices of use and concentration when formulated to be nonirritating. © The Author(s) 2015.
21 CFR 172.822 - Sodium lauryl sulfate.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium lauryl sulfate. 172.822 Section 172.822... Sodium lauryl sulfate. The food additive sodium lauryl sulfate may be safely used in food in accordance... of sodium alkyl sulfates consisting chiefly of sodium lauryl sulfate [CH2(CH2)10CH2OSO2Na]. (2) It...
Mesoporous silica film from a solution containing a surfactant and methods of making same
Liu, Jun [West Richland, WA; Domansky, Karel [Cambridge, MA; Li, Xiaohong [Richland, WA; Fryxell, Glen E [Kennewick, WA; Baskaran, Suresh [Kennewick, WA; Kohler, Nathan J [Richland, WA; Thevuthasan, Suntharampillai [Kennewick, WA; Coyle, Christopher A [Richland, WA; Birnbaum, Jerome C [Richland, WA
2001-12-11
The present invention is a mesoporous silica film having a low dielectric constant and method of making having the steps of combining a surfactant in a silica precursor solution, spin-coating a film from this solution mixture, forming a partially hydroxylated mesoporous film, and dehydroxylating the hydroxylated film to obtain the mesoporous film. It is advantageous that the small polyoxyethylene ether surfactants used in spin-coated films as described in the present invention will result in fine pores smaller on average than about 20 nm. The resulting mesoporous film has a dielectric constant less than 3, which is stable in moist air with a specific humidity. The present invention provides a method for superior control of film thickness and thickness uniformity over a coated wafer, and films with low dielectric constant.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ding, Wei -Liang
1999-02-12
Addition of a novel anionic surfactant, namely lauryl polyoxyethylene sulfate, to an aqueous-acetonitrile electrolyte makes it possible to separate nonionic organic compounds by capillary electrophoresis. Separation is based on differences in the association between analytes and the surfactant. Highly hydrophobic compounds such as polyaromatic hydrocarbons are well separated by this new surfactant. Migration times of analytes can be readily changed over an unusually large range by varying the additive concentration and the proportion of acetonitrile in the electrolyte. Several examples are given, including the separation of four methylbenz[a]anthracene isomers and the separation of normal and deuterated acetophenone. The effect ofmore » adding this new surfactant to the acidic electrolyte was also investigated. Incorporation of cetyltrimethylammonium bromide in the electrolyte is shown to dynamically coat the capillary and reverse electroosmotic flow. Chiral recognition mechanism is studied using novel synthetic surfactants as chiral selectors, which are made from amino acids reacting with alkyl chloroformates. A satisfactory separation of both inorganic and organic anions is obtained using electrolyte solutions as high as 5 M sodium chloride using direct photometric detection. The effect of various salts on electrophoretic and electroosmotic mobility is further discussed. Several examples are given under high-salt conditions.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baichenko, A.A.; Kaminskii, V.S.; Sokolova, V.S.
1977-01-01
Laboratory data are presented on the degradation of polyoxyethylene during storage and under mechanical and chemical action. Provided the physico-chemical properties of the polymer are considered and conditions are adjusted to minimize its degradation during solution preparation, POE can be used as a highly effective flocculant for the commercial filtration of flotation concentrate.
Haineault, Caroline; Gourde, Pierrette; Perron, Sylvie; Désormeaux, André; Piret, Jocelyne; Omar, Rabeea F; Tremblay, Roland R; Bergeron, Michel G
2003-08-01
The contraceptive properties of a gel formulation containing sodium lauryl sulfate were investigated in both in vitro and in vivo models. Results showed that sodium lauryl sulfate inhibited, in a concentration-dependent manner, the activity of sheep testicular hyaluronidase. Sodium lauryl sulfate also completely inhibited human sperm motility as evaluated by the 30-sec Sander-Cramer test. The acid-buffering capacity of gel formulations containing sodium lauryl sulfate increased with the molarity of the citrate buffers used for their preparations. Furthermore, experiments in which semen was mixed with undiluted gel formulations in different proportions confirmed their physiologically relevant buffering capacity. Intravaginal application of the gel formulation containing sodium lauryl sulfate to rabbits before their artificial insemination with freshly ejaculated semen completely prevented egg fertilization. The gel formulation containing sodium lauryl sulfate was fully compatible with nonlubricated latex condoms. Taken together, these results suggest that the gel formulation containing sodium lauryl sulfate could represent a potential candidate for use as a topical vaginal spermicidal formulation to provide fertility control in women.
21 CFR 178.3480 - Fatty alcohols, synthetic.
Code of Federal Regulations, 2010 CFR
2010-04-01
... derived lauryl alcohol permitted as an intermediate in the synthesis of sodium lauryl sulfate used in..._locations.html. (1) Synthetic fatty alcohols. (i) Hexyl, octyl, decyl, lauryl, myristyl, cetyl, and stearyl... they may contain not more than 0.8 weight percent total diols. (ii) Lauryl, myristyl, cetyl, and...
NASA Technical Reports Server (NTRS)
Levine, L. H.; Judkins, J. E.; Garland, J. L.; Sager, J. C. (Principal Investigator)
2000-01-01
A direct approach utilizing ion pairing reversed-phase chromatography coupled with suppressed conductivity detection was developed to monitor biodegradation of anionic surfactants during wastewater recycling through hydroponic plant growth systems and fixed-film bioreactors. Samples of hydroponic nutrient solution and bioreactor effluent with high concentrations (up to 120 mS electrical conductance) of inorganic ions can be analyzed without pretreatment or interference. The presence of non-ionic surfactants did not significantly affect the analysis. Dynamic linear ranges for tested surfactants [Igepon TC-42, ammonium lauryl sulfate, sodium laureth sulfate and sodium alkyl (C10-C16) ether sulfate] were 2 to approximately 500, 1 to approximately 500, 2.5 to approximately 550 and 3.0 to approximately 630 microg/ml, respectively.
Guimarães, José S; Bogado, Alexey L Gomel; da Cunha, Thiago Cezar B; Garcia, João Luis
2007-01-01
The objective of this study was to evaluate in vitro the action of eight chemical principles by disinfection efficacy (DE) of Eimeria tenella oocysts. Disinfection efficacy was evaluated by either destruction or sporulation inhibition of the oocysts. Eight treatments were performed: T1 (Glutaraldehyde 42.5 g + Benzalkonium Chloride 7.5 g); T2 (Benzalkonium chloride + quaternary ammonium salt); T3 (formol 37% + Sodium Dodecylbenzene Sulfonate 12%); T4 (sodium hypochlorite 2%); T5 (Orthodichlorobenzene 60% + Xylene 30%); T6 (Polyoctyl polyamino ethyl glycine + Polyoxyethylene alkylphenol ether + Sodium Chloride); T7 (Chloramine T) and finally T8 (free iodine 2.25% + Phosphoric acid 15 g). The control test was carried out with distilled water (T9). The best DE were observed, respectively, in T3 (79.49%), T5 (75.60%) and T4 (65.56%) treatments.
Inoue, Tohru; Higuchi, Yuka; Misono, Takeshi
2009-10-01
The melting behavior of polyethyleneglycol dodecyl ethers (C(12)E(6), C(12)E(7), and C(12)E(8)) in a room temperature ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF(4)), was investigated by means of differential scanning calorimetry (DSC). The melting temperature as a function of the surfactant concentration, combined with the cmc curve and cloud point curve, provided phase diagrams for the surfactant/bmimBF(4) mixtures in solvent-rich region. The characteristic feature of the mixtures is an existence of the Krafft temperature which is usually not observed with aqueous solutions of nonionic surfactants. The heat of fusion as a function of the surfactant concentration provided the interaction energy between the surfactant and bmimBF(4). The interaction energy shows a linear dependence on the length of polyoxyethylene (POE) chain of the surfactants, which suggests that the solvation takes place around the POE chain.
The Physiology, Biochemistry and Genetics of Survival of Bacteria Subjected to Environmental Stress
1981-11-01
sodium lauryl sulfate , but not to sodtimnl chloride or streptomycin alone. This sensitivity was again transient and capable of... sodium lauryl sulfate but not to sodium chloride or streptomycin alone. This sensitivity was again transient and capable of repair in the name simple...polymyxin B, bacitracin, and sodium lauryl . - 19 sutfate during growth, to ethylenediaminetetraacetic acid and sodium lauryl AUTHOR: 20 sulfate in
Ríos, Francisco; Fernández-Arteaga, Alejandro; Lechuga, Manuela; Fernández-Serrano, Mercedes
2017-04-01
This paper reports on a study that investigated the aquatic toxicity of new non-ionic surfactants derived from renewable raw materials, polyoxyethylene glycerol ester (PGE), and their binary mixtures with anionic and non-ionic surfactants. Toxicity of pure PGEs was determined using representative organisms from different trophic levels: luminescent bacteria (Vibrio fischeri), microalgae (Pseudokirchneriella subcapitata), and freshwater crustaceans (Daphnia magna). Relationships between toxicity and the structural parameters such as unit of ethylene oxide (EO) and hydrophilic-lipophilic balance (HLB) were evaluated. Critical micellar concentration (CMC) in the conditions of the toxicity test was also determined. It was found that the toxicity of the aqueous solutions of PGE decreased when the number of EO units in the molecule, HLB, and CMC increased. PGEs showed lower CMC in marine medium, and the toxicity to V. ficheri is lower when the CMC was higher. Given their non-polar nature, narcosis was expected to be the primary mode of toxic action of PGEs. For the mixture of surfactants, we observed that the mixtures with PGE that had the higher numbers of EO units were more toxic than the aqueous solutions of pure surfactants. Moreover, we found that concentration addition was the type of action more likely to occur for mixtures of PGE with lower numbers of EO units with non-ionic surfactants (alkylpolyglucoside and fatty alcohol ethoxylate), whereas for the mixture of PGE with lower EO units and anionic surfactant (ether carboxylic derivative), the most common response type was response addition. In case of mixtures involving amphoteric surfactants and PGEs with the higher numbers of EO units, no clear pattern with regard to the mixture toxicity response type could be observed.
21 CFR 177.1632 - Poly (phenyl-enetereph-thala-mide) resins.
Code of Federal Regulations, 2010 CFR
2010-04-01
...). Poly(oxyethylene) sorbitol monolaurate tetraoleate (CAS Reg. No. 71243-28-2). Poly(oxyethylene) sorbitol hexaoleate (CAS Reg. No. 57171-56-9). 4,4′-Butylidenebis (6-tert-butyl-m-cresol) (CAS Reg. No. 85...
Supercritical CO2/Co-solvents Extraction of Porogen and Surfactant to Obtain
NASA Astrophysics Data System (ADS)
Lubguban, Jorge
2005-03-01
A method of pore generation by supercritical CO2 (SCCO2)/co-solvents extraction for the preparation of nanoporous organosilicate thin films for ultralow dielectric constant materials is investigated. A nanohybrid film was prepared from poly (propylene glycol) (PPG) and poly(methylsilsesquioxane) (PMSSQ) whereby the PPG porogen are entrapped within the crosslinked PMSSQ matrix. Another set of thin films was produced by liquid crystal templating whereby non-ionic (polyoxyethylene 10 stearyl ether) (Brij76) and ionic (cetyltrimethylammonium bromide) (CTAB) surfactant were used as sacrificial templates in a tetraethoxy silane (TEOS) and methyltrimethoxy silane (MTMS) based matrix. These two types of films were treated with SCCO2/co-solvents to remove porogen and surfactant templates. As a comparison, porous structures generated by thermal decomposition were also evaluated. It is found that SCCO2/co-solvents treatment produced closely comparable results with thermal decomposition. The results were evident from Fourier Transform Infrared (FT- IR) spectroscopy and optical constants data obtained from variable angle spectroscopic ellipsometry (VASE).
Hildebrandt, K M; Anderson, J S
1990-01-01
Cytoplasmic membrane fragments of Micrococcus luteus catalyze in vitro biosynthesis of teichuronic acid from uridine diphosphate D-glucose (UDP-glucose), uridine diphosphate N-acetyl-D-mannosaminuronic acid (UDP-ManNAcA), and uridine diphosphate N-acetyl-D-glucosamine. Membrane fragments solubilized with Thesit (dodecyl alcohol polyoxyethylene ether) can utilize UDP-glucose and UDP-ManNAcA to effect elongation of teichuronic acid isolated from native cell walls. When UDP-glucose is the only substrate supplied, the detergent-solubilized glucosyltransferase incorporates a single glucosyl residue onto each teichuronic acid acceptor. When both UDP-glucose and UDP-ManNAcA are supplied, the glucosyltransferase and the N-acetylmannosaminuronosyltransferase act cooperatively to elongate the teichuronic acid acceptor by multiple additions of the disaccharide repeat unit. As shown by polyacrylamide gel electrophoresis, low-molecular-weight fractions of teichuronic acid are converted to higher-molecular-weight polymers by the addition of as many as 17 disaccharide repeat units. Images PMID:2118507
Effect of surfactant on single drop mass transfer for extraction of aromatics from lubricating oils
NASA Astrophysics Data System (ADS)
Izza, H.; Ben Abdessalam, S.; Korichi, M.
2018-03-01
Solvent extraction is an effective method for the reduction of the content of aromatic of lubricating oil. Frequently, with phenol, furfural, the NMP (out of N-methyl pyrrolidone). The power solvent and the selectivity can be still to increase while using surfactant as additive which facilitates the separation of phase and increases the yeild in raffinat. Liquid-liquid mass transfer coefficients for single freely rising drops in the presence of surfactant in an extraction column have been investigated. The surfactant used in this study was sodium lauryl ether sulfate (SLES). The experiments were performed by bubbling a solvent as a series of individual drops from the top of the column containing furfural-SLES solution. The column used in this experiment was made from glass with 17 mm inner diameter and a capacity of 125ml. The effects of the concentration of surfactant on the overall coefficient of mass transfer was investigated.
Removal of heavy metals from waste streams
DOE Office of Scientific and Technical Information (OSTI.GOV)
Spence, M.D.; Kozaruk, J.M.; Melvin, M.
1988-07-19
A method for removing heavy metals from effluent water is described comprising performing sequentially the following steps: (a) adding from 7-333 ppm of an anionic surfactant to the effluent water to provide coagulatable heavy metal ion; (b) adjusting the effluent water pH to within the range of 8 to 10, (c) providing from 10-200 ppm of a cationic coagulant to coagulate the heavy metal ion, (d) providing from 0.3 to 5.0 ppm of a polymeric flocculant whereby a heavy metal containing floc is formed for removal from the effluent water, and, (e) then removing the floc from the effluent water,more » wherein the anionic surfactant is sodium lauryl ether sulfate. The cationic coagulant is selected from the group consisting of diallyl dimethylammonium chloride polymer, epichlorohydrin dimethylamine polymer, ethylene amine polymer, polyaluminum chloride, and alum; and the flocculant is an acrylamide/sodium acrylate copolymer having an RSV greater than 23.« less
Chang, Shih-Hsien; Wang, Kai-Sung; Hu, Pei-I; Lui, I-Chun
2009-04-30
Copper-surfactant wastewaters are often encountered in electroplating, printed circuit boards manufacturing, and metal finishing industries, as well as in retentates from micellar-enhanced ultrafiltration process. A low-cost three-dimensional steel wool cathode reactor was evaluated for electrolytic recovery of Cu ion from dilute copper solution (0.2mM) in the presence of sodium dodecyl sulfate (SDS), octylphenol poly (ethyleneglycol) 9.5 ether (TX), nonylphenol poly (oxyethylene) 9 ether (NP9) and polyoxyethylene (20) sorbitan monooleate (TW) and also mixed surfactants (anionic/nonionic). The reactor showed excellent copper recovery ability in comparison to a parallel-plate reactor. The reactor rapidly recovered copper with a reasonable current efficiency. 93% of copper was recovered at current density of 1 A m(-2) and pH 4 in the presence of 8.5mM SDS. Initial solution pH, cathodic current density, solution mixing condition, SDS concentration, and initial copper concentrations significantly influenced copper recovery. The copper recovery rate increased with an increase in aqueous SDS concentrations between 5 and 8.5mM. The influences of nonionic surfactants on Cu recovery from SDS-Cu solution depended not only on the type of surfactants used, but also on applied concentrations. From the copper recovery perspective, TX at 0.1mM or NP should be selected rather than TW, because they did not inhibit copper recovery from SDS-Cu solution.
Nibu; Suemori; Inoue
1997-07-01
Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were used to construct and characterize the phase diagram for a binary mixture of heptaethylene glycol decyl ether (C10 E7 ) and water in the temperature range from -60 to 80°C. Plots of the endothermic peak temperatures obtained by DSC measurements against compositions provided eutectic solid-liquid phase boundaries with a eutectic composition of 34 wt% of H2 O. On the other hand, heat of fusion per unit weight of the mixture changed discretely at the composition corresponding to the "eutectic" composition. Furthermore, the IR spectra obtained for the mixture in the solid phase were well reproduced as a superposition of those for the mixture of 34 wt% H2 O and pure components but were not reproduced by superimposing the spectra obtained for the solid surfactant and ice. These observations indicate that a solid phase compound is formed between C10 E7 and water with a stoichiometry of 1:14 and that the compound and pure components exist as separate phases, rather than the phases separating into surfactant and ice, which would be expected if the C10 E7 /water mixture formed a true eutectic mixture system. It is estimated from the composition corresponding to the phase compounds that two molecules of water per oxyethylene unit are bound to hydrophilic polyoxyethylene chain of C10 E7 to form a hydrated compound.
21 CFR 172.834 - Ethoxylated mono- and diglycerides.
Code of Federal Regulations, 2010 CFR
2010-04-01
... ethoxylated mono-and diglycerides (polyoxyethylene (20) mono- and diglycerides of fatty acids) (polyglycerate... labeling it shall be followed by either “polyoxyethylene (20) mono-and diglycerides of fatty acids” or... myristic acids; or (2) Direct esterification of glycerol with a mixture of primarily stearic, palmitic, and...
Feuser, Paulo Emilio; Arévalo, Juan Marcelo Carpio; Junior, Enio Lima; Rossi, Gustavo Rodrigues; da Silva Trindade, Edvaldo; Rocha, Maria Eliane Merlin; Jacques, Amanda Virtuoso; Ricci-Júnior, Eduardo; Santos-Silva, Maria Claudia; Sayer, Claudia; de Araújo, Pedro H Hermes
2016-12-01
Lauryl gallate loaded in superparamagnetic poly(methyl methacrylate) nanoparticles surface modified with folic acid were synthesized by miniemulsion polymerization in just one step. In vitro biocompatibility and cytotoxicity assays on L929 (murine fibroblast), human red blood, and HeLa (uterine colon cancer) cells were performed. The effect of folic acid at the nanoparticles surface was evaluated through cellular uptake assays in HeLa cells. Results showed that the presence of folic acid did not affect substantially the polymer particle size (~120 nm), the superparamagnetic behavior, the encapsulation efficiency of lauryl gallate (~87 %), the Zeta potential (~38 mV) of the polymeric nanoparticles or the release profile of lauryl gallate. The release profile of lauryl gallate from superparamagnetic poly(methyl methacrylate) nanoparticles presented an initial burst effect (0-1 h) followed by a slow and sustained release, indicating a biphasic release system. Lauryl gallate loaded in superparamagnetic poly(methyl methacrylate) nanoparticles with folic acid did not present cytotoxicity effects on L929 and human red blood cells. However, free lauryl gallate presented significant cytotoxic effects on L929 and human red blood cells at all tested concentrations. The presence of folic acid increased the cytotoxicity of lauryl gallate loaded in nanoparticles on HeLa cells due to a higher cellular uptake when HeLa cells were incubated at 37 °C. On the other hand, when the nanoparticles were incubated at low temperature (4 °C) cellular uptake was not observed, suggesting that the uptake occurred by folate receptor mediated energy-dependent endocytosis. Based on presented results our work suggests that this carrier system can be an excellent alternative in targeted drug delivery by folate receptor.
NASA Astrophysics Data System (ADS)
Shen, Liguo; Li, Jianxi; Li, Renjie; Lin, Hongjun; Chen, Jianrong; Liao, Bao-Qiang
2018-04-01
In this study, a new strategy which blends low-density polyethylene (LDPE), magnesium hydroxide (MH) and lauryl acrylate by electron-beam radiation for production of LDPE-based composites with high performance was proposed. It was found that, MH played main roles in flame retardancy but reduced processing flow and mechanical properties of the composites. Meanwhile, melt flow rate (MFR) increased while viscosity of the composites decreased with lauryl acrylate content increased, facilitating LDPE composites processing. Electron beam radiation could prompt crosslinking of lauryl acrylate, which significantly enhanced the mechanical properties of LDPE composites. Meanwhile, lauryl acrylate addition only slightly decreased the flame retardancy, suggesting that LDPE composites could remain high flame retardancy even when lauryl acrylate content was high. The study highly demonstrated the feasibility to produce LDPE-based composites simultaneously with high flame retardancy and high mechanical properties by the blending strategy provided in this study.
21 CFR 172.810 - Dioctyl sodium sulfo-suc-cinate.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Dioctyl sodium sulfo-suc-cinate. 172.810 Section... combination with α-hydro-omega -hydroxy - poly(oxyethylene) - poly-(oxypropylene) (53-59 moles) poly(oxyethylene) (14-16 moles) block copolymer, having a molecular weight range of 3,500-4,125 and a cloud point...
21 CFR 172.810 - Dioctyl sodium sulfo-suc-cinate.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Dioctyl sodium sulfo-suc-cinate. 172.810 Section... combination with α-hydro-omega -hydroxy - poly(oxyethylene) - poly-(oxypropylene) (53-59 moles) poly(oxyethylene) (14-16 moles) block copolymer, having a molecular weight range of 3,500-4,125 and a cloud point...
21 CFR 172.810 - Dioctyl sodium sulfo-suc-cinate.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Dioctyl sodium sulfo-suc-cinate. 172.810 Section... combination with α-hydro-omega -hydroxy - poly(oxyethylene) - poly-(oxypropylene) (53-59 moles) poly(oxyethylene) (14-16 moles) block copolymer, having a molecular weight range of 3,500-4,125 and a cloud point...
21 CFR 172.810 - Dioctyl sodium sulfo-suc-cinate.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Dioctyl sodium sulfo-suc-cinate. 172.810 Section... combination with α-hydro-omega -hydroxy - poly(oxyethylene) - poly-(oxypropylene) (53-59 moles) poly(oxyethylene) (14-16 moles) block copolymer, having a molecular weight range of 3,500-4,125 and a cloud point...
Yamaguchi, Shunsuke; Tsuchiya, Koji; Sakai, Kenichi; Abe, Masahiko; Sakai, Hideki
2016-01-01
We have previously reported a new preparation method for liposomes using supercritical carbon dioxide (scCO2) as a solvent, referred to as the supercritical carbon dioxide reverse phase evaporation (scRPE) method. In our previous work, addition of ethanol to scCO2 as a co-solvent was needed, because lipid molecules had to be dissolved in scCO2 to form liposomes. In this new study, niosomes (nonionic surfactant vesicles) were prepared from various nonionic surfactants using the scRPE method. Among the nonionic surfactants tested were polyoxyethylene (6) stearylether (C18EO6), polyoxyethylene (5) phytosterolether (BPS-5), polyoxyethylene (6) sorbitan stearylester (TS-106V), and polyoxyethylene (4) sorbitan stearylester (Tween 61). All these surfactants have hydrophilic-lipophilic balance values (HLBs) around 9.5 to 9.9, and they can all form niosomes using the scRPE method even in the absence of ethanol. The high solubility of these surfactants in scCO2 was shown to be an important factor in yielding niosomes without ethanol addition. The niosomes prepared with the scRPE method had higher trapping efficiencies than those prepared using the conventional Bangham method, since the scRPE method gives a large number of unilamellar vesicles while the Bangham method gives multilamellar vesicles. Polyoxyethylene-type nonionic surfactants with HLB values from 9.5 to 9.9 were shown to be optimal for the preparation of niosomes with the scRPE method.
Bhattachar, Shobha N; Risley, Donald S; Werawatganone, Pornpen; Aburub, Aktham
2011-06-30
This work reports on the solubility of two weakly basic model compounds in media containing sodium lauryl sulfate (SLS). Results clearly show that the presence of SLS in the media (e.g. simulated gastric fluid or dissolution media) can result in an underestimation of solubility of some weak bases. We systematically study this phenomenon and provide evidence (chromatography and pXRD) for the first time that the decrease in solubility is likely due to formation of a less soluble salt/complex between the protonated form of the weak base and lauryl sulfate anion. Copyright © 2011 Elsevier B.V. All rights reserved.
Lee, S; McAuliffe, D J; Kollias, N; Flotte, T J; Doukas, A G
2001-01-01
Photomechanical waves render the stratum corneum permeable and allow macromolecules to diffuse into the epidermis and dermis. The aim of this study was to investigate the combined action of photomechanical waves and sodium lauryl sulfate, an anionic surfactant, for transdermal delivery. A single photomechanical wave was applied to the skin of rats in the presence of sodium lauryl sulfate. The sodium lauryl sulfate solution was removed and aqueous solutions of rhodamine-B dextran (40 kDa molecular weight) were applied to the skin at time points 2, 30, and 60 minutes post-exposure. The presence of rhodamine-B dextran in the skin was measured by fluorescence emission spectroscopy in vivo and fluorescence microscopy of frozen biopsies. The use of sodium lauryl sulfate delayed the recovery of the stratum corneum barrier and extended the time available for the diffusion of dextran through it. The combination of photomechanical waves and surfactants can enhance transdermal drug delivery. Copyright 2001 Wiley-Liss, Inc.
Zhang, Xiao-fang; Zhu, Bi-lin; Li, Wei; Wang, Lei; Zhang, Lei; Wu, Ting; Du, Yi-ping
2015-07-01
In this paper, a method of determination of trace lead in water by UV-Visible diffuse reflectance spectroscopy combined with surfactant and membrane filtration enrichment was proposed. In the NH3 x H2O-NH4Cl buffer solution with pH 8.5, the lead(II) ion would react with dithizone to form the red complex under vigorous stirring, which is hydrophobic and can be enriched by the mixed cellulose ester membrane. In addition, the nonionic surfactant Polyoxyethylene lauryl ether (Brij-30) was added into the solution to improve the enrichment efficiency, then visible diffuse reflectance spectra of the membrane were measured directly after the membrane were naturally dried. We also optimized the reaction conditions which may affect the complexation reaction process, such as type of surfactants, the concentration of the surfactant, the reaction acidity, the concentration of dithizone as well as the reaction time. The research results show that under the optimum conditions, a good linear correlation between absorbance at 485 nm and concentration of lead in the range of 5.0-100.0 microg x L(-1) was obtained with a squared correlation coefficient (R2) of 0.9906, and the detection limit was estimated accordingly to be 2.88 microg x L(-1). To determine real water sample, the interference from some potential coexisting ions was also studied at the optimal conditions when the concentration of lead (II) ion standard solution was fixed to 20 microg x L(-1). The results indicate that the following ions cannot interfere in the determination of lead with the proposed method: 500 times of the K+, Na+, Ca2+, Mg2+, NH4+, NO3-, Cl-, CH3COO-, SO4(2-); 10 times of the Al3+ (using 10% NaF as a masking reagent to avoid the interference); 10 times of the Fe3+ (using 10% NaF and 10% sodium potassium tartrate as masking reagents); 10 times of Hg2+ or Zn2+ (using 10% NaSCN and 10% potassium sodium tartrate as masking reagents); the same amount of Cd2+, Cu2+. The proposed method was applied to the determnation of lead (II) in bottled water as a real sample. The determination results show good agreements between the proposed method and graphite furnace atomic absorption spectrometry (GFAAS) method. The recoveries in case of spiked real samples were between 95.4% and 104.5%, and the standard deviations (SD) were between 0.5 micro x L(-1) and 1.5 microg x L(-1), which indicate that the method developed in the present work with advantages of accuracy, simpleness, sensitiveness are of potential application for the determination of trace lead in water samples.
Enhanced Oxidation and Solvolysis Reactions in Chemically Inert Microheterogeneous Systems.
1986-01-15
has been found in a O/W microemulsion containing sodium lauryl sulfate , cyclohexane, n-butanol and water. SHORT TERM PROJECTS New O/W and W/O...microemulsion containing lauryl acid sodium salt, cyclohexane, n-butanol and water towards hydrogen peroxide has been tested. Kinetic measurements...using hydrogen peroxide The system lauryl acid sodium salt, cyclohexane, n-butanol, water has been selected as one of those potentially compatible
Development of a Methodology for the Rapid Detection of Coliform Bacteria.
1981-02-27
Micelle Concentration Determination of Sodium Lauryl Sulfate 19 10 Sheath Flow Measuring Chamber 24 ll(a-c) Negative Substrate Control Comparisons 27...the net result being a net increase in the level of detectability. Sodium lauryl sulfate was chosen as the candidate surfactant and used at its...determined experimentally by taking conductivity mea- surements for a concentration series of sodium lauryl sulfate . Plotting equivalent conductivity vs
Preformulation and Formulation of Investigational New Drugs
1985-07-01
Sodium Lauryl Sulfate (SLS) on the Degradation of Dilute Solutions (0,5 mg/ml) of HI-6 in pH 5.74 Citrate Buffer...Stability was enhanced by the use of sodium lauryl sulfate but not by the use of sodium taurocholate. ,q,.l 9 MethodoloUy Reagents HI-6CI, (WRAIR... sodium hydroxide, citric acid monohydrate, concentrated hydro- Uchloric acid, sodium chloride (Mallinckrodt); sodium lauryl sulfate , (Pfaltz and
21 CFR 172.810 - Dioctyl sodium sulfosuccinate.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Dioctyl sodium sulfosuccinate. 172.810 Section 172...-hydro-omega -hydroxy - poly(oxyethylene) - poly-(oxypropylene) (53-59 moles) poly(oxyethylene) (14-16 moles) block copolymer, having a molecular weight range of 3,500-4,125 and a cloud point of 9 °C-12 °C...
Transdermal Drug Delivery System. Stage 1. Volume 3
1987-12-30
lauryl sulfate (0.33%) docusate sodium (0.35%) and potassium laurate (1%) were tested and found not irritating to rabbit skin. Formulations of 50% S...hydroxypropylmethylcellulose (HPMC) gel containing either 0.198% sodium lauryl sulfate or 0.21% docusate sodium . A HPMC gel containing 50% S-26741...formulation excipients and combinations of both. S-26741 (neat chemical) and a 50% S-26741/0.33% sodium lauryl sulfate formulation were tested using the
Cellular localization and detergent dependent oligomerization of rice allene oxide synthase-1.
Yoeun, Sereyvath; Kim, Jeong-Il; Han, Oksoo
2015-01-01
Allene oxide synthase-1 from Oryza sativa (OsAOS1) localizes to the chloroplast, but lacks a putative chloroplast targeting sequence typically found in dicot AOS. Here, kinetic parameters and the oligomerization state/subunit composition of OsAOS1 were characterized in vitro in the absence or presence of detergent micelles. The catalytic efficiency (k(cat)/K(m)) of OsAOS1 reached a maximum near the critical micelle concentration for polyoxyethylene 10 tridecyl ether. Native gel analysis showed that OsAOS1 exists as a multimer in the absence of detergent micelles. The multimeric form of OsAOS1 was stably cross-linked in the absence of detergents, while only monomeric OsAOS1 was detected in the presence of detergent micelles. Gel filtration analysis indicated that the oligomeric state of OsAOS1 depends strongly on the detergents and that the monomer becomes the predominant form in the presence of detergent micelles. These data suggest that the detergent-dependent oligomeric state of OsAOS1 is an important factor for the regulation of its catalytic efficiency.
El-Hadidy, Gladious Naguib; Ibrahim, Howida Kamal; Mohamed, Magdi Ibrahim; El-Milligi, Mohamed Farid
2012-01-01
This work was undertaken to investigate microemulsion (ME) as a topical delivery system for the poorly water-soluble voriconazole. Different ME components were selected for the preparation of plain ME systems with suitable rheological properties for topical use. Two permeation enhancers were incorporated, namely sodium deoxycholate or oleic acid. Drug-loaded MEs were evaluated for their physical appearance, pH, rheological properties and in vitro permeation studies using guinea pig skin. MEs based on polyoxyethylene(10)oleyl ether (Brij 97) as the surfactant showed pseudoplastic flow with thixotropic behavior and were loaded with voriconazole. Jojoba oil-based MEs successfully prolonged voriconazole release up to 4 h. No significant changes in physical or rheological properties were recorded on storage for 12 months at ambient conditions. The presence of permeation enhancers favored transdermal rather than dermal delivery. Sodium deoxycholate was more effective than oleic acid for enhancing the voriconazole permeation. Voriconazole-loaded MEs, with and without enhancers, showed significantly better antifungal activity against Candida albicans than voriconazole supersaturated solution. In conclusion, the studied ME formulae could be promising vehicles for topical delivery of voriconazole.
Hong, Chi Rac; Park, Sung Joon; Choi, Seung Jun
2016-07-01
Surfactant-made micelles can control the rate of chemical degradation of poorly water-soluble food flavors. To evaluate how the molecular structure of surfactant has an influence on the chemical decomposition rate of citral, micelles were prepared with polyoxyethylene alkyl ether-type surfactants that had similar molecular structures but various hydrophilic head sizes and hydrophobic tail lengths. At a critical 20× micelle concentration of surfactant, there was no significant difference in the chemical degradation rate of citral in micelles in neutral pH, regardless of the hydrophilic head size or hydrophobic tail length. In an acidic environment, the degradation rate constant of citral generally increased proportionally with increasing hydrophilic head size of surfactant (0.1563 and 0.2217 for surfactants with 23 and 100 oxyethylene units, respectively) but the length of hydrophobic tail did not affect the citral stability. Also, little difference (0.2217 and 0.2265 for surfactant having 100 oxyethylene units with and without Fe(3+) ) in degradation rate constant of citral between simple micellar solution and micellar solution containing iron suggested that iron ions could not accelerate citral degradation in micelles, regardless of the form of iron (Fe(2+) and Fe(3+) ). This work concludes that although the concentration of surfactant could be relevant, if its concentration could be controlled in the same manner as the critical micelle concentration, then a polyethylene alkyl ether-type surfactant with a small hydrophilic head could more efficiently stabilize citral at an acidic pH. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.
Formulation and evaluation of antihyperglycemic leaf extracts of Zizyphus spina-christi (L.) Willd.
Nesseem, D I; Michel, C G; Sleem, A A; El-Alfy, T S
2009-02-01
This study deals with the formulation of antihyperglycemic leaf extracts of Zizyphus spina-christi (L.) Willd. A bioactivity guided fractionation of different leaf extracts [defatted ethanol 70% (a), butanol (b), ethanol 70% (c), ethyl acetate (d) and petroleum ether (e) extracts] revealed that extract (c) possessed the highest antihyperglycemic activity followed by (b) and (a). HPLC was adopted for standardization of the extract (c) based on evaluation of the major saponin christinin-A which was used as marker. The detection limit was 9.45 mg/ml for Christinin-A. Extracts (a), (b) and (c) were separately formulated in soft (S) and hard (H) gelatin capsules. Two different formulations (F1 and F2) were tried using different excipients suitable for oral drug delivery. Formula 1, used for soft gelatin capsules [(F1) Sa, Sb, Sc] Formula 2, used for hard gelatin capsules [(F2) - Ha, Hb, Hc]. The recovery rates of the samples of saponin were in the range 99.43-101.86% at 200, 800 microg/ml and 1200 microg/ml. Saponin release rates from different formulae were carried out using dissolution tester USP XXIV. The highest release was obtained from formulation Sc. The release of the extracts followed diffusion mechanism. The selected formula Sc exhibited highest anti-diabetic activity (P < 0.01) on acute and long-term administration and highest saponin release. This formula (Sc) contained poly-oxyethylene (20) cetyl ether (BC-20TX), PEG 400, PEG 6000, purified water, meglyol 810, ascorbic acid and 200 mg of extract (c).
Fogeron, Marie-Laure; Badillo, Aurélie; Jirasko, Vlastimil; Gouttenoire, Jérôme; Paul, David; Lancien, Loick; Moradpour, Darius; Bartenschlager, Ralf; Meier, Beat H; Penin, François; Böckmann, Anja
2015-01-01
Membrane proteins are notoriously difficult to express in a soluble form. Here, we use wheat germ cell-free expression in the presence of various detergents to produce the non-structural membrane proteins 2, 4B and 5A of the hepatitis C virus (HCV). We show that lauryl maltose neopentyl glycol (MNG-3) and dodecyl octaethylene glycol ether (C12E8) detergents can yield essentially soluble membrane proteins at detergent concentrations that do not inhibit the cell-free reaction. This finding can be explained by the low critical micelle concentration (CMC) of these detergents, which keeps the monomer concentrations low while at the same time providing the necessary excess of detergent concentration above CMC required for full target protein solubilization. We estimate that a tenfold excess of detergent micelles with respect to the protein concentration is sufficient for solubilization, a number that we propose as a guideline for detergent screening assays. Copyright © 2014 Elsevier Inc. All rights reserved.
Equilibration of a polycation - anionic surfactant mixture at the water/vapor interface.
Akanno, Andrew; Guzmán, Eduardo; Fernández-Peña, Laura; Llamas, Sara; Ortega, Francisco; Rubio, Ramon Gonzalez
2018-06-01
The adsorption of concentrated poly(diallyldimethylammonium chloride) (PDADMAC) - sodium lauryl ether sulfate (SLES) mixtures at the water / vapor interface has been studied by different surface tension techniques and dilational visco-elasticity measurements. This work tries to shed light on the way in which the formation of polyelectrolyte - surfactant complexes in the bulk affects to the interfacial properties of mixtures formed by a polycation and an oppositely charged surfactant. The results are discussed in terms of a two-step adsorption-equilibration of PDADMAC - SLES complexes at the interface, with the initial stages involving the diffusion of kinetically trapped aggregates formed in the bulk to the interface followed by the dissociation and spreading of such aggregates at the interface. This latter process becomes the main contribution to the surface tension decrease. This work helps on the understanding of the most fundamental bases of the physico-chemical behavior of concentrated polyelectrolyte - surfactant mixtures which present complex bulk and interfacial interactions with interest in both basic and applied sciences.
NASA Astrophysics Data System (ADS)
Blagojević, S. M.; Pejić, N. D.; Blagojević, S. N.
2017-12-01
The physicochemical properties of initial formulation, that is anionic/amphoteric surfactants mixture SLES/AOS/CAB (sodium lauryl ether sulfate (SLES), α-olefin sulfonates (AOS) and cocamidopropyl betaine (CAB) at ratio 80 : 15 : 5) with nonionic surfactant of amine oxide type (lauramine oxide (AO)) in various concentration (1-5%) were studied. To characterize the surfactants mixture, the critical micelle concentration (CMC), surface tension (γ), foam volume, biodegradability and irritability were determined. This study showed that adding of AO in those mixtures lowered both γ and CMC as well as enhanced SLES/AOS/CAB foaming properties, but did not significantly affect biodegradability and irritability of initial formulation. Moreover, an increase in AO concentration has a meaningful synergistic effect on the initial formulation properties. All those results indicates that a nonionic surfactant of amine oxide type significantly improves the performance of anionic/amphoteric mixed micelle systems, and because of that anionic/amphoteric/nonionic mixture can be used in considerably lower concentrations as a cleaning formulation.
Kerwin, Bruce A
2008-08-01
Polysorbates 20 and 80 (Tween 20 and Tween 80) are used in the formulation of biotherapeutic products for both preventing surface adsorption and as stabilizers against protein aggregation. The polysorbates are amphipathic, nonionic surfactants composed of fatty acid esters of polyoxyethylene sorbitan being polyoxyethylene sorbitan monolaurate for polysorbate 20 and polyoxyethylene sorbitan monooleate for polysorbate 80. The polysorbates used in the formulation of biopharmaceuticals are mixtures of different fatty acid esters with the monolaurate fraction of polysorbate 20 making up only 40-60% of the mixture and the monooleate fraction of polysorbate 80 making up >58% of the mixture. The polysorbates undergo autooxidation, cleavage at the ethylene oxide subunits and hydrolysis of the fatty acid ester bond. Autooxidation results in hydroperoxide formation, side-chain cleavage and eventually formation of short chain acids such as formic acid all of which could influence the stability of a biopharmaceutical product. Oxidation of the fatty acid moiety while well described in the literature has not been specifically investigated for polysorbate. This review focuses on the chemical structure of the polysorbates, factors influencing micelle formation and factors and excipients influencing stability and degradation of the polyoxyethylene and fatty acid ester linkages.
Dermal Sensitization Potential of Niclosamide in Guinea Pigs
1988-09-01
al--3 sterile water, from the same lot as for DNCB stock solution, were used to prepare the dilutions of FCA. Sodium lauryl sulfate (SLS) was obtained...test agent was non- irritating, the area was pretreated with 10% sodium lauryl sulfate in petrolatum immediately after the clipping and shaving. The SLS...control combination was prepared by adding 0.25 ml of FCA stock to 4.75 ml of propylene glycol. Topical Induction and Challenge: The sodium lauryl
Coatings and Biodegradable and Bioabsorbable Films
2006-09-01
Properties Properties (Latex) Properties (Paint) M1. 726-39 Sodium lauryl sulfate 2.27 phi Control APS Viscous caossy, some Acceptablecracks, fo a y" l...SS 726-49 Sodium laufyl sulfate 2.17 phr Control APS Viscous, foamy Cracks in film Foam SIS 726-51 Sodium lauryl sulfate 2.17 phi Control APS Crashed...Not Formulated Not Formulated SS 726-35 Sodium lauryl sulfate 2.17 phr Control APS Acceptable Glossy with some Unusually foamy ________ _______fo am
Control of Foaming by Adding Known Mixtures of Pure Chemicals
1949-04-01
Sodium lauryl sulfate — do -- „NACA^ 12 FACA TN No. I8k2 TABLE VIII,- AEROSOL OT HUH DIEFEBBHT, SÜBSTABCE3 IK AEBOSHELL 120...80 34.2 Nacconal NRSF 400 —_—-<-(Lo ■— 80 49.6 Sodium lauryl sulfonate 300 do —— - 90 49.6 Sapamine MS 400 do- 80 52.1 Lauryl sulfonic acid...400 do-- 80 ^9.8 Sodium heptadecyl sulfate 400 do — - — 80 7.6 Sodium octyl sulfate 4oo —do - 80 46.8 --.— Xylidines 10,000 51.5
2004-01-01
Antibacterial peptide acylation, which mimics the structure of the natural lipopeptide polymyxin B, increases antimicrobial and endotoxin-neutralizing activities. The interaction of the lactoferricin-derived peptide LF11 and its N-terminally acylated analogue, lauryl-LF11, with different chemotypes of bacterial lipopolysaccharide (LPS Re, Ra and smooth S form) was investigated by biophysical means and was related to the peptides' biological activities. Both peptides exhibit high antibacterial activity against the three strains of Salmonella enterica differing in the LPS chemotype. Lauryl-LF11 has one order of magnitude higher activity against Re-type, but activity against Ra- and S-type bacteria is comparable with that of LF11. The alkyl derivative peptide lauryl-LF11 shows a much stronger inhibition of the LPS-induced cytokine induction in human mononuclear cells than LF11. Although peptide–LPS interaction is essentially of electrostatic nature, the lauryl-modified peptide displays a strong hydrophobic component. Such a feature might then explain the fact that saturation of the peptide binding takes place at a much lower peptide/LPS ratio for LF11 than for lauryl-LF11, and that an overcompensation of the negative LPS backbone charges is observed for lauryl-LF11. The influence of LF11 on the gel-to-liquid-crystalline phase-transition of LPS is negligible for LPS Re, but clearly fluidizing for LPS Ra. In contrast, lauryl-LF11 causes a cholesterol-like effect in the two chemotypes, fluidizing in the gel and rigidifying of the hydrocarbon chains in the liquid-crystalline phase. Both peptides convert the mixed unilamellar/non-lamellar aggregate structure of lipid A, the ‘endotoxic principle’ of LPS, into a multilamellar one. These data contribute to the understanding of the mechanisms of the peptide-mediated neutralization of endotoxin and effect of lipid modification of peptides. PMID:15344905
Roll-on perfume compositions containing polyoxybutylene-polyoxyethylene copolymers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schmolka, I.R.
1987-05-26
This patent describes a liquid roll-on composition containing, in weight percent based upon the total composition weight, from 5 percent to 15 percent of a perfume oil, from 25 percent to 40 percent of a volatile alcohol, from 10 percent to 60 percent water, and from 10 percent to 30 percent of a nonionic polyether surfactant. The improvement comprises employing as the nonionic polyether surfactant a cogeneric polyoxybutylene-polyoxyethylene block copolymer.
1990-12-01
benzophenone (Aldrich 23:985-2), tetrabutylammonium nitrate (Kodak 9664), sodium lauryl sulfate (dodecyl sulfide, sodium salt) (Aldrich 86-201-0), helium gas...phase buffer for the initial identity confirmation using a Supelco LC-I column by dissolving 6.0 g of sodium lauryl sulfate and 1.0 g of...water, glacial acetic acid (Baker Reagent’Grade), tetrabutylammonium chloride (Aldrich g8. percent), sodium lauryl sulfate (Aldrich 98 percent), sodium
Lyotropic liquid crystalline phase behaviour in amphiphile-protic ionic liquid systems.
Chen, Zhengfei; Greaves, Tamar L; Fong, Celesta; Caruso, Rachel A; Drummond, Calum J
2012-03-21
Approximate partial phase diagrams for nine amphiphile-protic ionic liquid (PIL) systems have been determined by synchrotron source small angle X-ray scattering, differential scanning calorimetry and cross polarised optical microscopy. The binary phase diagrams of some common cationic (hexadecyltrimethyl ammonium chloride, CTAC, and hexadecylpyridinium bromide, HDPB) and nonionic (polyoxyethylene (10) oleyl ether, Brij 97, and Pluronic block copolymer, P123) amphiphiles with the PILs, ethylammonium nitrate (EAN), ethanolammonium nitrate (EOAN) and diethanolammonium formate (DEOAF), have been studied. The phase diagrams were constructed for concentrations from 10 wt% to 80 wt% amphiphile, in the temperature range 25 °C to >100 °C. Lyotropic liquid crystalline phases (hexagonal, cubic and lamellar) were formed at high surfactant concentrations (typically >50 wt%), whereas at <40 wt%, only micelles or polydisperse crystals were present. With the exception of Brij 97, the thermal stability of the phases formed by these surfactants persisted to temperatures above 100 °C. The phase behaviour of amphiphile-PIL systems was interpreted by considering the PIL cohesive energy, liquid nanoscale order, polarity and ionicity. For comparison the phase behaviour of the four amphiphiles was also studied in water.
Effect of H2O2 and nonionic surfactant in alkaline copper slurry
NASA Astrophysics Data System (ADS)
Haobo, Yuan; Yuling, Liu; Mengting, Jiang; Guodong, Chen; Weijuan, Liu; Shengli, Wang
2015-01-01
For improving the polishing performance, in this article, the roles of a nonionic surfactant (Fatty alcohol polyoxyethylene ether) and H2O2 were investigated in the chemical mechanical planarization process, respectively. Firstly, the effects of the nonionic surfactant on the within-wafer non-uniformity (WIWNU) and the surface roughness were mainly analyzed. In addition, the passivation ability of the slurry, which had no addition of BTA, was also discussed from the viewpoint of the static etch rate, electrochemical curve and residual step height under different concentrations of H2O2. The experimental results distinctly revealed that the nonionic surfactant introduced in the slurry improved the WIWNU and surface roughness, and that a 2 vol% was considered as an appropriate concentration relatively. When the concentration of H2O2 surpasses 3 vol%, the slurry will possess a relatively preferable passivation ability, which can effectively decrease the step height and contribute to acquiring a flat and smooth surface. Hence, based on the result of these experiments, the influences of the nonionic surfactant and H2O2 are further understood, which means the properties of slurry can be improved.
Exploring the Effects of Different Types of Surfactants on Zebrafish Embryos and Larvae
Wang, Yanan; Zhang, Yuan; Li, Xu; Sun, Mingzhu; Wei, Zhuo; Wang, Yu; Gao, Aiai; Chen, Dongyan; Zhao, Xin; Feng, Xizeng
2015-01-01
Currently, surfactants are widely distributed in the environment. As organic pollutants, their toxicities have drawn extensive attention. In this study, the effects of anionic [sodium dodecyl sulphate (SDS) ], cationic [dodecyl dimethyl benzyl ammonium chloride (1227)] and non-ionic [fatty alcohol polyoxyethylene ether (AEO) ] surfactants on zebrafish larval behaviour were evaluated. Five behavioural parameters were recorded using a larval rest/wake assay, including rest total, number of rest bouts, rest bouts length, total activity and waking activity. The results revealed that 1227 and AEO at 1 μg/mL were toxic to larval locomotor activity and that SDS had no significant effects. Moreover, we tested the toxicities of the three surfactants in developing zebrafish embryos. AEO exposure resulted in smaller head size, smaller eye size and shorter body length relative to SDS and 1227. All three surfactants incurred concentration-dependent responses. Furthermore, in situ hybridisation indicated that smaller head size may be associated with a decreased expression of krox20. The altered expression of ntl demonstrated that the developmental retardation stemmed from inhibited cell migration and growth. These findings provide references for ecotoxicological assessments of different types of surfactants, and play a warning role in the application of surfactants. PMID:26053337
Effect of surfactant on kinetics of thinning of capillary bridges
NASA Astrophysics Data System (ADS)
Nowak, Emilia; Kovalchuk, Nina; Simmons, Mark
2015-11-01
Kinetics of thinning of capillary bridges is of great scientific and industrial interest being of vital importance for example in various emulsification and microfluidic processes. It is well known that the rate of bridge thinning is proportional to the interfacial tension. Therefore it is expected that the process should slow down by addition of surfactant. The kinetics of capillary bridges in the presence of surfactant was studied by the dripping of liquid from a capillary tip under conditions of nearly zero flow rate (We << 1). The tested liquids were aqueous solutions of sodium lauryl ether sulphate (SLES), which is broadly used in personal care products. The viscosity, surfactant activity and adsorption kinetics have been controlled by addition of glycerol and sodium chloride. The study has shown that the kinetics of capillary bridges are determined by dynamic surface tension rather than by its equilibrium value. In particular, the kinetics of the bridge thinning for the 0.1 g L-1 aqueous SLES solution is practically the same as that of pure water despite twice lower equilibrium surface tension. EPSRC Programme Grant, MEMPHIS, EP/K0039761/1.
Biodegradation of sodium lauryl ether sulfate (SLES) by two different bacterial consortia.
Khleifat, Khaled M
2006-11-01
Two bacterial consortia capable of degrading SLES were isolated from a wastewater treatment plant. The two consortia consisted of three members, Acinetobacter calcoacetiacus and Klebsiella oxytoca in one co-culture (A-K) and Serratia odorifera in the second co-culture (S-A), which contains Acinetobacter calcoacetiacus as well. In all experiments, cells were grown on SLES (1000-7000 ppm) containing the M9 minimal medium as sole carbon source. The co-culture A-K demonstrated a higher growth rate (0.26 h(-1)) and significant greater viability than that of the co-culture S-A (0.21 h(-1)). Glucose, sucrose, maltose, mannitol, and succinic acid as carbon sources produced the same degradation rate (approximately 100 ppm/h) and enhanced the SLES degradation rate by 3-fold upon the control (without an added carbon source). In the case of the co-culture S-A, the situation was different; all the carbon sources being tested except maltose caused a repression in the degradation ability in a range between 25-100%. Maltose causes an enhancement by almost fivefold, compared with the positive control.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Niwa, Masazo; Hayashi, Takehiro; Higashi, Nobuyuki
1990-01-01
Amphiphilic block polymers (2,3) composed of poly(acrylic acid) (PAA) or poly(oxyethylene) (POE) and chain length controlled poly(styrene) (PSt) have been prepared by using a catalytic system of tribromomethyl-terminated oligomer and manganese carbonyl. All the amphiphilic materials formed well-behaved surface monolayers, and the II-A curves for them expanded systematically with an increase of the PSt chain length.
Saraji, M; Shirvani, N
2017-02-01
Polyethoxylated surfactants are widely used in the formulation of different cleaning agents such as shampoo, dish washing and hand washing products and lotion formulation. During the production of polyethoxylated surfactants, 1,4-dioxane as a toxic and carcinogenic by-product is formed. A simple low-cost method based on headspace single-drop microextraction combined with gas chromatography-flame ionization detection was developed for the determination of 1,4-dioxane in surfactants and cleaning agents. In this method, 1,4-dioxane was extracted from 8.0 mL sample solution into a microdrop of an organic solvent, and then, it was injected to gas chromatography. The effects of such parameters as the solvent type, salt addition, microdrop volume, stirring rate, equilibrium time, extraction time and the temperature of sample solution on the extraction performance were studied and optimized. An ethoxylated surfactant containing 1,4-dioxane was used as the sample for the optimization of the extraction parameters. The linear range, determination coefficient, limit of detection and relative standard deviation of the method were 0.5-100 μg g -1 , 0.9977, 0.4 μg g -1 and 7.2% (n = 5), respectively. Different real samples including sodium lauryl ether sulphate, sodium lauryl sulphate (SLS), four brands of shampoo, and hand washing and dish washing liquids were analysed by the method. 1,4-Dioxane was detected at the concentration range of 2.4-201 μg g -1 in the samples, except dish washing liquid and SLS. A new method with the merits of simplicity, low cost, low organic solvent consumption, short analysis time, good repeatability and suitable detection limit was developed for the analysis of 1,4-dioxane in surfactants and cleaning agents. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.
Formation of hollow silica nanospheres by reverse microemulsion
NASA Astrophysics Data System (ADS)
Lin, Cheng-Han; Chang, Jen-Hsuan; Yeh, Yi-Qi; Wu, Si-Han; Liu, Yi-Hsin; Mou, Chung-Yuan
2015-05-01
Uniform hollow silica nanospheres (HSNs) synthesized with reverse microemulsion have great application potential as nanoreactors because enzymes or nanocatalysts can be easily encapsulated de novo in synthesis. Water-in-oil (w/o) reverse microemulsions comprising the polymeric surfactant polyoxyethylene (5) isooctylphenyl ether (Igepal CA-520), ammonia and water in a continuous oil phase (alkanes) coalesce into size-tunable silica nanoparticles via diffusion aggregation after the introduction of silica precursors. Here, we elucidate in detail the growth mechanism for silica nanoparticles via nucleation of ammonium-catalyzed silica oligomers from tetraethylorthosilicate (TEOS) and nanoporous aminopropyltrimethoxy silane (APTS) in the reverse microemulsion system. The formation pathway was studied in situ with small-angle X-ray scattering (SAXS). We find a four-stage process showing a sigmoidal growth behavior in time with a crossover from the induction period, early nucleation stage, coalescence growth and a final slowing down of growth. Various characterizations (TEM, N2 isotherm, dynamic light scattering, zeta potential, NMR, elemental analysis) reveal the diameters, scattering length density (SLD), mesoporosity, surface potentials and chemical compositions of the HSNs. Oil phases of alkanes with different alkyl chains are systematically employed to tune the sizes of HSNs by varying oil molar volumes, co-solvent amounts or surfactant mixture ratios. Silica condensation is incomplete in the core region, with the silica source of TEOS and APTS leading to the hollow silica nanosphere after etching with warm water.Uniform hollow silica nanospheres (HSNs) synthesized with reverse microemulsion have great application potential as nanoreactors because enzymes or nanocatalysts can be easily encapsulated de novo in synthesis. Water-in-oil (w/o) reverse microemulsions comprising the polymeric surfactant polyoxyethylene (5) isooctylphenyl ether (Igepal CA-520), ammonia and water in a continuous oil phase (alkanes) coalesce into size-tunable silica nanoparticles via diffusion aggregation after the introduction of silica precursors. Here, we elucidate in detail the growth mechanism for silica nanoparticles via nucleation of ammonium-catalyzed silica oligomers from tetraethylorthosilicate (TEOS) and nanoporous aminopropyltrimethoxy silane (APTS) in the reverse microemulsion system. The formation pathway was studied in situ with small-angle X-ray scattering (SAXS). We find a four-stage process showing a sigmoidal growth behavior in time with a crossover from the induction period, early nucleation stage, coalescence growth and a final slowing down of growth. Various characterizations (TEM, N2 isotherm, dynamic light scattering, zeta potential, NMR, elemental analysis) reveal the diameters, scattering length density (SLD), mesoporosity, surface potentials and chemical compositions of the HSNs. Oil phases of alkanes with different alkyl chains are systematically employed to tune the sizes of HSNs by varying oil molar volumes, co-solvent amounts or surfactant mixture ratios. Silica condensation is incomplete in the core region, with the silica source of TEOS and APTS leading to the hollow silica nanosphere after etching with warm water. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr01395j
Characterisation of chlorophyll a solubilised in sodium lauryl sulphate micelles
NASA Astrophysics Data System (ADS)
Mukherjee, T.; Sapre, A. V.; Mittal, Jai P.
1980-01-01
Poisson statistics has been applied to the problem of solubilisation of chlorophyll a in sodium lauryl sulphate micelles. Dilution experiments have been carried out to support the finding that each unit of chlorophyll a contributing to the 740 nm band contains just one chlorophyll a molecule.
Park, Young-Joon; Ryu, Dong-Sung; Li, Dong Xun; Quan, Qi Zhe; Oh, Dong Hoon; Kim, Jong Oh; Seo, Youn Gee; Lee, Young-Im; Yong, Chul Soon; Woo, Jong Soo; Choi, Han-Gon
2009-06-01
To develop a novel tacrolimus-loaded solid dispersion with improved solubility, various solid dispersions were prepared with various ratios of water, sodium lauryl sulfate, citric acid and carboxylmethylcellulose-Na using spray drying technique. The physicochemical properties of solid dispersions were investigated using scanning electron microscopy, differential scanning calorimetery and powder X-ray diffraction. Furthermore, their solubility and dissolution were evaluated compared to drug powder. The solid dispersion at the tacrolimus/CMC-Na/sodium lauryl sulfate/citric acid ratio of 3/24/3/0.2 significantly improved the drug solubility and dissolution compared to powder. The scanning electron microscopy result suggested that carriers might be attached to the surface of drug in this solid dispersion. Unlike traditional solid dispersion systems, the crystal form of drug in this solid dispersion could not be converted to amorphous form, which was confirmed by the analysis of DSC and powder X-ray diffraction. Thus, the solid dispersion system with water, sodium lauryl sulfate, citric acid and CMC-Na should be a potential candidate for delivering a poorly water-soluble tacrolimus with enhanced solubility and no convertible crystalline.
Antiviral activity of lauryl gallate against animal viruses.
Hurtado, Carolina; Bustos, Maria Jose; Sabina, Prado; Nogal, Maria Luisa; Granja, Aitor G; González, Maria Eugenia; Gónzalez-Porqué, Pedro; Revilla, Yolanda; Carrascosa, Angel L
2008-01-01
Antiviral compounds are needed in the control of many animal and human diseases. We analysed the effect of the antitumoural drug lauryl gallate on the infectivity of the African swine fever virus among other DNA (herpes simplex and vaccinia) and RNA (influenza, porcine transmissible gastroenteritis and Sindbis) viruses, paying attention to its effect on the viability of the corresponding host cells. Viral production was strongly inhibited in different cell lines at non-toxic concentrations of the drug (1-10 microM), reducing the titres 3->5 log units depending on the multiplicity of infection. In our model system (African swine fever virus in Vero cells), the addition of the drug 1 h before virus adsorption completely abolished virus productivity in a one-step growth virus cycle. Interestingly, no inhibitory effect was observed when lauryl gallate was added after 5-8 h post-infection. Both cellular and viral DNA synthesis and late viral transcription were inhibited by the drug; however, the early viral protein synthesis and the virus-mediated increase of p53 remained unaffected. Activation of the apoptotic effector caspase-3 was not detected after lauryl gallate treatment of Vero cells. Furthermore, the presence of the drug abrogated the activation of this protease induced by the virus infection. Lauryl gallate is a powerful antiviral agent against several pathogens of clinical and veterinary importance. The overall results indicate that a cellular factor or function might be the target of the antiviral action of alkyl gallates.
NASA Astrophysics Data System (ADS)
Yang, Fang; Li, Gang; Qi, Jian; Zhang, Song-Mei; Liu, Rong
2010-10-01
A series of trimeric n-alkylphenol polyoxyethylene surfactants (TAP) were successfully synthesized and the molecular structure were confirmed by NMR, FTIR spectrum and elemental analysis. Using the same synthesis route, the trimeric nonylphenol polyoxyethylene surfactant (TNP) was synthesized using industrial product nonylphenol and paraformaldehyde, and its molecular structure was characterized by 1HNMR, FTIR spectrum and elemental analysis. The optimal reaction conditions were established. The surface activity properties of TAP and TNP (such as the critical micelle concentration (cmc), the values of surface tension at the cmc ( γcmc), the maximum surface excess concentration ( Γcmc), and the minimum surface area per surfactant molecule ( Acmc)), were determined by means of Wilhelmy plate method and steady-state fluorescence probe method, respectively. The experimental results show that the lengths of the hydrophilic group oxyethylene (EO) chains and hydrophobic group methylene chains have an influence on the cmc, γcmc, Γcmc, and Acmc of series of surfactants. Furthermore, TAP are arranged to staggered three-dimensional array mode at the air-water interface, which has exhibited better surface properties, such as low cmc values, strong adsorption affinities and wet abilities.
Piret, Jocelyne; Laforest, Geneviève; Bussières, Martin; Bergeron, Michel G
2008-03-01
The safety of an ethylene oxide/propylene oxide gel formulation containing sodium lauryl sulfate (2%, w/w), that could be a potent candidate as a topical microbicide, has been evaluated. More specifically, the subchronic (26- and 52-week) toxicity of the formulation when applied intravaginally as well as its irritating potential for the rectal, penile, eye, skin and buccal mucosa have been examined in animal models. The results showed that the vaginal administration of the gel formulation containing sodium lauryl sulfate once and twice daily (with doses 12 +/- 2 h apart) for 26 weeks to rats and for 52 weeks to rabbits induced slight to moderate histopathological alterations. When the formulation was applied intrarectally to male and female rabbits once and twice daily (with doses 12 +/- 2 h apart) for 14 days, no macroscopic or microscopic changes were reported. For both vaginal and rectal dosing, no effect was seen on the haematology, coagulation and serum chemistry parameters as well as on the body weight of animals and the relative organ weights. Other sporadic macroscopic and histopathological findings were incidental in origin and of no toxicological significance. The gel formulation containing sodium lauryl sulfate was considered as mildly irritating for the penile mucosa of rabbits, non-irritating for the eye of rabbits, mildly irritating for the skin in a rabbit model and non-irritating for the hamster cheek pouch. It is suggested that the gel formulation containing sodium lauryl sulfate is safe for most tissues that could be exposed to the product under normal use.
NASA Astrophysics Data System (ADS)
Özden, Pınar; Nesrullajev, Arif; Oktik, Şener
2010-12-01
Phase states in sodium lauryl sulphate-water-1-decanol lyotropic liquid-crystalline system have been investigated for different temperature ranges. The dependence of triangle phase diagram types, phase boundaries, and sequence of lyotropic mesophases vs temperature has been found. The thermomorphologic, thermotropic, and magnetomorphologic properties of hexagonal E, lamellar D, nematic-calamitic NC , nematic-discotic ND , and biaxial nematic Nbx mesophases have been studied in detail. Dynamics of transformations of magnetically induced textures has been investigated. Peculiarities of typical and magnetically induced textures have been investigated in detail. Triangle phase diagrams of sodium lauryl sulphate-water-1-decanol lyotropic liquid-crystalline system for different temperatures and typical and magnetically induced textures of E, D, NC , ND , and Nbx mesophases are presented.
Stability of a Cosmetic Multiple Emulsion Loaded with Green Tea Extract
Mahmood, Tariq; Akhtar, Naveed
2013-01-01
Multiple emulsions are excellent and exciting potential systems for the delivery of useful cosmetic agents. The work describes stability of a multiple emulsion for cosmetic purpose, loaded with extract of Camellia sinensis L. (Theaceae) in concentration of 5%. The formulation constitutes of cetyl dimethicone copolyol and polyoxyethylene (20) cetyl ether as emulsifiers and was characterised and monitored for various physicochemical aspects. Centrifugation has no devastating effect on physical destabilization/phase separation observed for 30 days. Mean globule sizes of multiple droplets were found in the range of 10.29 ± 4.4 μm to 12.77 ± 5.1 μm and of inner droplets were in the range of 0.8 ± 0.4 μm to 1.6 ± 0.8 μm. All samples exhibited shear thinning behavior with increase in shear stress. The results of the present study indicate that multiple emulsions can be used as carrier of 5% Camellia sinensis L. extract to enhance desired effects. The developed physically and chemically stable system is an effective system for targeting skin layers; however, long-term stability at elevated temperatures may be needed with suitable modifications, if required. PMID:24058284
Lu, Wen-Chien; Chiang, Been-Huang; Huang, Da-Wei; Li, Po-Hsien
2014-03-01
Nanoemulsions can be used for transporting pharmaceutical phytochemicals in skin-care products because of their stability and rapid permeation properties. However, droplet size may be a critical factor aiding permeation through skin and transdermal delivery efficiency. We prepared D-limonene nanoemulsions with various droplet sizes by ultrasonic emulsification using mixed surfactants of sorbitane trioleate and polyoxyethylene (20) oleyl ether under different hydrophilic-lipophilic balance (HLB) values. Droplet size decreased with increasing HLB value. With HLB 12, the droplet size was 23 nm, and the encapsulated ratio peaked at 92.3%. Transmission electron microscopy revealed spherical droplets and the gray parts were D-limonene precipitation incorporated in spherical droplets of the emulsion system. Franz diffusion cell was used to evaluate the permeation of D-limonene nanoemulsion through rat abdominal skin; the permeation rate depended on droplet size. The emulsion with the lowest droplet size (54 nm) achieved the maximum permeation rate. The concentration of D-limonene in the skin was 40.11 μL/cm(2) at the end of 360 min. Histopathology revealed no distinct voids or empty spaces in the epidermal region of permeated rat skin, so the D-limonene nanoemulsion may be a safe carrier for transdermal drug delivery. Copyright © 2013 Elsevier B.V. All rights reserved.
Shear rheology and in-vitro release kinetic study of apigenin from lyotropic liquid crystal.
Fan, Jun; Liu, Feng; Wang, Zhongni
2016-01-30
Apigenin is a flavonoid compound with diverse pharmacological functions which could develop health benefit products, but its formulation is hampered by its poor water solubility and bioavailability. In this paper, in order to overcome these difficulties, apigenin was encapsulated in LLC formed by polyoxyethylene-10-oleyl ether (Brij 97) and sodium deoxycholate (NaDC) mixtures. The hexagonal liquid crystalline phase (H) and the cubic liquid crystalline phase (C) were found in this system. The shear rheology was used to study the structure change with temperature. It was shown that C3 (Brij 97-NaDC/IPM-PEG400/H2O=36:9:55) was C at low temperature. But above 35.6°C, the matrix of C3 completely transformed to polymer solution. The matrix of H3 was H (Brij 97-NaDC:IPM-PEG 400:H2O=50:9:41) below 50°C, but the structural strength change was obvious. Vitro release experiment was used to study drug release kinetics. It was indicated that apigenin encapsulated in LLC conformed to the concentration diffusion model, and cumulative percentage of apigenin released from C3 and H3 had corresponding relationship with the shear rheology at different temperatures. Copyright © 2015. Published by Elsevier B.V.
Evaluation of certain food additives.
2015-01-01
This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, including flavouring agents, and to prepare specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation of and assessment of dietary exposure to food additives, including flavouring agents. A summary follows of the Committee's evaluations of technical, toxicological and dietary exposure data for eight food additives (Benzoe tonkinensis; carrageenan; citric and fatty acid esters of glycerol; gardenia yellow; lutein esters from Tagetes erecta; octenyl succinic acid-modified gum arabic; octenyl succinic acid-modified starch; paprika extract; and pectin) and eight groups of flavouring agents (aliphatic and alicyclic hydrocarbons; aliphatic and aromatic ethers; ionones and structurally related substances; miscellaneous nitrogen-containing substances; monocyclic and bicyclic secondary alcohols, ketones and related esters; phenol and phenol derivatives; phenyl-substituted aliphatic alcohols and related aldehydes and esters; and sulfur-containing heterocyclic compounds). Specifications for the following food additives were revised: citric acid; gellan gum; polyoxyethylene (20) sorbitan monostearate; potassium aluminium silicate; and Quillaia extract (Type 2). Annexed to the report are tables summarizing the Committee's recommendations for dietary exposures to and toxicological evaluations of all of the food additives and flavouring agents considered at this meeting.
Limiting solubilizing capacity of some nonionic surfactants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wan, L.S.C.
1980-12-01
This report gives an account of the attempts to solubilize corn oil. A fixed quantity of corn oil or oily dispersion containing corn oil and a sorbitan ester was added to a series of 25 ml of polysorbate solutions of increasing concentration. This investigation showed that corn oil is not solubilized by either aqueous solutions of polyoxyethylene sorbitan esters or by a combination of these surfactants with sorbitan esters. The findings suggest that nonionic surfactants of the polyoxyethylene sorbitan ester type as well as the sorbitan esters have limiting capacities to solubilize extremely hydrophobic substances such as corn oil. 19more » references.« less
Dugan, Patrick R.; Apel, William A.
1983-01-01
The application of an aqueous solution of sodium lauryl sulfate and sodium benzoate to the surface of high-sulfur coal refuse resulted in the inhibition of iron-and sulfur-oxidizing chemoautotrophic bacteria and in the decrease of acidic drainage from the refuse, suggesting that acid drainage can be abated in the field by inhibiting iron- and sulfur-oxidizing bacteria. PMID:16346347
The Effect of Liquid Gun Propellant (LGP) on Skin.
1992-02-27
sodium lauryl sulfate ) decreased the barrier properties of hairless guinea pig skin to the greatest extent after I day, and the barrier returned to normal...San Francisco, CA. Wilhelm K.-P., Surber, C. and Maibach, H.I. Effect of sodium lauryl sulfate - induced skin irritation on in vivo percutaneous...NJ), followed by an intravenous injection of sodium pentobarbital (18 mg/kg, Anthony Products, Arcadia, CA). A Padgett Electro Dermatome (Padgett
Quality Evaluation of Herbs and Spices in The Military Food System
1976-06-01
tested would inhibit bacterial growth, Eseheric- hia coli and Staphyloeoeeus aureus were inoculated in tubes of lauryl sulfate tryptose (LST) broth... lauryl sulfate tryptose (LST) broth by standard methods**. Gas producing LST tubes were confirmed in brilliant green lactose bile (2%) broth (BGLB...and trypticase soy broth (TSB) containing 10% sodium chloride (NaCl), respectively, to which was added 1 ml of 1:10 dilution of each spice
Onysko, Steven J.; Kleinmann, Robert L. P.; Erickson, Patricia M.
1984-01-01
Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds. PMID:16346592
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang Jilin; Shi Jianxin, E-mail: chemshijx@163.co; Gong Menglian
2009-08-15
Nickel ferrite nanospheres were successfully synthesized by a reverse emulsion-assisted hydrothermal method. The reverse emulsion was composed of water, cetyltrimethyl ammonium bromide, polyoxyethylene(10)nonyl phenyl ether, iso-amyl alcohol and hexane. During the hydrothermal process, beta-FeO(OH) and Ni{sub 0.75}Fe{sub 0.25}(CO{sub 3}){sub 0.125}(OH){sub 2}.0.38H{sub 2}O (INCHH) nanorods formed first and then transformed into nickel spinel ferrite nanospheres. The phase transformation mechanism is proposed based on the results of X-ray powder diffraction, transmission electron microscopy and energy-dispersive X-ray spectroscopy, etc. Nickel ferrite may form at the end of the INCHH nanorods or from the solution accompanied by the dissolution of beta-FeO(OH) and INCHH nanorods.more » The X-ray photoelectron spectroscopy analysis shows that a few Fe{sup 3+} ions have been reduced to Fe{sup 2+} ions during the formation of nickel ferrite. The maximum magnetization of the nickel ferrite nanospheres obtained after hydrothermal reaction for 30 h is 55.01 emu/g, which is close to that of bulk NiFe{sub 2}O{sub 4}. - Graphical abstract: Nickel ferrite nanospheres were obtained through a reverse emulsion-assisted hydrothermal process. The phase transformation as a function of reaction time was studied based on the XRD, TEM and EDS analyses.« less
Research and Development of Wound Dressing in Maxillofacial Trauma.
1982-06-23
duplicate samples with and without 0.002% sodium lauryl sulfate . Values in parentheses are assays in CH 2C12/CH 3OH. 16 A representative section of fabric...tested, with and without 0.002% sodium lauryl sulfate as a wetting agent. Since there was no obvious effect of the surfactant, the results are averaged...aqueous). The precipitates were then washed with ethanol. Lidocaine sulfate has a melting point of u 2150C and is slightly soluble in water. Lidocaine
Fiume, Monice; Bergfeld, Wilma F; Belsito, Donald V; Klaassen, Curtis D; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Alan Andersen, F
2010-05-01
Sodium cetearyl sulfate is the sodium salt of a mixture of cetyl and stearyl sulfate. The other ingredients in this safety assessment are also alkyl salts, including ammonium coco-sulfate, ammonium myristyl sulfate, magnesium coco-sulfate, sodium cetyl sulfate, sodium coco/hydrogenated tallow sulfate, sodium coco-sulfate, sodium decyl sulfate, sodium ethylhexyl sulfate, sodium myristyl sulfate, sodium oleyl sulfate, sodium stearyl sulfate, sodium tallow sulfate, sodium tridecyl sulfate, and zinc coco-sulfate. These ingredients are surfactants used at concentrations from 0.1% to 29%, primarily in soaps and shampoos. Many of these ingredients are not in current use. The Cosmetic Ingredient Review (CIR) Expert Panel previously completed a safety assessment of sodium and ammonium lauryl sulfate. The data available for sodium lauryl sulfate and ammonium lauryl sulfate provide sufficient basis for concluding that sodium cetearyl sulfate and related alkyl sulfates are safe in the practices of use and concentration described in the safety assessment.
Cheong, Jean Ne; Mirhosseini, Hamed; Tan, Chin Ping
2010-06-01
The main objective of the present study was to investigate the effect of polyoxyethylene sorbitan esters and sodium caseinate on physicochemical properties of palm-based functional lipid nanodispersions prepared by the emulsification-evaporation technique. The results indicated that the average droplet size increased significantly (P < 0.05) by increasing the chain length of fatty acids and also by increasing the hydrophile-lipophile balance value. Among the prepared nanodispersions, the nanoemulsion containing Polysorbate 20 showed the smallest average droplet size (202 nm) and narrowest size distribution for tocopherol-tocotrienol nanodispersions, while sodium caseinate-stabilized nanodispersions containing carotenoids had the largest average droplet size (386 nm), thus indicating a greater emulsifying role for Polysorbate 20 compared with sodium caseinate.
Mycobacteriocins produced by rapidly growing mycobacteria are Tween-hydrolyzing esterases.
Saito, H; Tomioka, H; Watanabe, T; Yoneyama, T
1983-01-01
Smegmatocin, a protein produced by Mycobacterium smegmatis ATCC 14468, was found to have an esterase activity, hydrolyzing Tween 80, polyoxyethylene sorbitan monooleate, added to the assay medium for various "bacteriocins" from mycobacteria. Because M. diernhoferi ATCC 19340 (indicator strain for smegmatocin) is highly susceptible to oleic acid and smegmatocin requires Tween 80 for manifestation of its anti-M. diernhoferi activity, it is likely that smegmatocin-mediated antimicrobial action is caused by oleic acid generated by hydrolysis of Tween 80 by the inherent esterase action of smegmatocin. Other mycobacteriocins from rapidly growing mycobacteria also have inherent esterase activity against Tween 80 and require Tween 80 for expression of antimycobacterial action. Smegmatocin was found to hydrolyze various polyoxyethylene (sorbitan) fatty acyl esters but not sorbitan monooleate and glyceryl esters. Images PMID:6826523
Brunelli, Elvira; Talarico, Erminia; Corapi, Barbara; Perrotta, Ida; Tripepi, Sandro
2008-10-01
We analysed the morphology and ultrastructure of the gill apparatus of the ornate wrasse, Thalassoma pavo, under normal conditions and after exposure to a sublethal concentration of sodium lauryl sulphate (3.5 mg/l, which is one-third of the 96LC99 value). To identify the biochemical mechanisms affected by this pollutant, we evaluated and compared the localisation of Na(+)/K(+) ATPase in normal and experimental conditions. Immunocytochemical analysis revealed that this enzyme was active in the chloride cells (CCs), which were distributed in clusters in the interlamellar region of the filament. Ultrastructural analysis revealed conspicuous alterations on the epithelium after 96 and 192 h of exposure to sodium lauryl sulphate: structural features of the surface cells were lost, the appearance of intercellular lacunae changed, and cellular degeneration occurred. Statistical analysis comparing the number and dimensions of CCs in normal conditions and after 96 h of exposure showed that the CC area decreased after exposure to the detergent.
Inert Reassessment Document for Poly(oxyethylene)(5) sorbitan monooleate
The sorbitan fatty acid esters and polysorbates are inert ingredients used as surfactants, related adjuvants of surfactants, emulsifiers, buffering agents, and corrosion inhibitors in a variety of pesticide products.
Low-Level Effects of VX Vapor Exposure on Pupil Size and Cholinesterase Levels in Rats
2005-03-01
Longwood, FL) along with 25 tL of 2.08 mM sodium lauryl sulfate in a pH 7.2 phosphate buffer (30 mM). The plate was read at 536 nm and 37°C using a...Hemoglobin Determination by Using Sodium Lauryl Sulfate (SLS). Clin. Biochem. 15(1) 83-88 (1982). Prins, J., "Product and Process Comparison," Chapter 7...standard VX-G were eluted with I mL ethyl acetate that was collected and dried over anhydrous sodium sulfate . The ethyl acetate was removed from the
NASA Astrophysics Data System (ADS)
Al-Latief, D. N.; Arnelli, Astuti, Y.
2015-12-01
Surfactant-modified active carbon (SMAC) has been successfully synthesized from waste rice husk using a series of treatments i.e. carbonization, activation with H3PO4 and surface modification using sodium lauryl sulfate (SLS). The synthesized SMAC was characterized using SEM-EDX and FTIR. The adsorption results show that the SMAC synthesized using H3PO4 treatment for 8 hours followed with SLS treatment for 5 hours had efficiency and capacity of the waste lead removal of 99.965% and 0.499825 mg.g-1, respectively.
Dasgupta, Sudip; Bandyopadhyay, Amit; Bose, Susmita
2010-01-01
Calcium phosphate (CaP) nanoparticle with calcium to phosphorus (Ca:P) molar ratio of 1.5:1 were synthesized using reverse micro emulsion. Ca(NO3)2.4H2O and H3PO4 were used as aqueous phase, cyclohexane as organic phase, and poly(oxyethylene)12 nonylphenol ether (NP-12) as surfactant. Depending on calcination temperature between 600 and 800 °C, CaP nanoparticle showed different phases calcium deficient hydroxyapatite (CDHA) and β-tricalcium phosphate (β-TCP), particle size between 48 and 69 nm, the BET specific average surface area between 73 m2/g and 57 m2/g. Bovine serum albumin (BSA) was used as a model protein to study loading and release behavior. Adsorptive property of BSA was investigated with the change in BET surface area of these nanoparticle and the pH of the suspension. At pH 7.5, maximum amount of BSA was adsorbed onto CaP nanoparticle. The release kinetics of BSA showed a gradual time dependent increase at pH 4.0 and 6.0 buffer solutions. However, the amount of released protein was significantly smaller at pH 7.2. BSA release rate also varied depending on the presence of different phases of CaPs in the system, β-TCP or CDHA. These results suggest that BSA protein release rate can be controlled by changing particle size, surface area and phase composition of CaP nanocarriers. PMID:19435617
Gabboun, N H; Najib, N M; Ibrahim, H G; Assaf, S
2001-01-05
Release of salicylic acid, diclofenac acid, diclofenac diethylamine and diclofenac sodium, from lyotropic structured systems, namely; neat and middle liquid crystalline phases, across mid-dorsal hairless rat skin into aqueous buffer were studied. Release results were compared with those from the isotropic systems. The donor systems composed of the surfactant polyoxyethylene (20) isohexadecyl ether, HCl buffer of pH 1 or distilled water and the specific drug. High performance liquid chromatography (HPLC) methods were used to monitor the transfer of the drugs across the skin barrier. Results indicated that the rate-determining step in the transport process was the release of the drug from the specified donor system. Further, apparent zero order release was demonstrated with all systems. Except for diclofenac sodium, drug fluxes decreased as the donor medium changed from isotropic to anisotropic. The decrease in fluxes was probably due to the added constrains on the movement of drug molecules. By changing the anisotropic donor medium from neat to middle phase, drug flux decreased in case of salicylic acid and diclofenac sodium. In the mean time, flux increased in case of the diethylamine salt and appeared nearly similar in case of diclofenac acid. Rates of drug transfer across the skin from the anisotropic donors seemed to be largely controlled by the entropy contribution to the transport process. The type and extent of drug-liquid crystal interactions probably influenced the latter.
Development of New Lipid-Based Paclitaxel Nanoparticles Using Sequential Simplex Optimization
Dong, Xiaowei; Mattingly, Cynthia A.; Tseng, Michael; Cho, Moo; Adams, Val R.; Mumper, Russell J.
2008-01-01
The objective of these studies was to develop Cremophor-free lipid-based paclitaxel (PX) nanoparticle formulations prepared from warm microemulsion precursors. To identify and optimize new nanoparticles, experimental design was performed combining Taguchi array and sequential simplex optimization. The combination of Taguchi array and sequential simplex optimization efficiently directed the design of paclitaxel nanoparticles. Two optimized paclitaxel nanoparticles (NPs) were obtained: G78 NPs composed of glyceryl tridodecanoate (GT) and polyoxyethylene 20-stearyl ether (Brij 78), and BTM NPs composed of Miglyol 812, Brij 78 and D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS). Both nanoparticles successfully entrapped paclitaxel at a final concentration of 150 μg/ml (over 6% drug loading) with particle sizes less than 200 nm and over 85% of entrapment efficiency. These novel paclitaxel nanoparticles were stable at 4°C over three months and in PBS at 37°C over 102 hours as measured by physical stability. Release of paclitaxel was slow and sustained without initial burst release. Cytotoxicity studies in MDA-MB-231 cancer cells showed that both nanoparticles have similar anticancer activities compared to Taxol®. Interestingly, PX BTM nanocapsules could be lyophilized without cryoprotectants. The lyophilized powder comprised only of PX BTM NPs in water could be rapidly rehydrated with complete retention of original physicochemical properties, in-vitro release properties, and cytotoxicity profile. Sequential Simplex Optimization has been utilized to identify promising new lipid-based paclitaxel nanoparticles having useful attributes. PMID:19111929
Mahmood, Tariq; Akhtar, Naveed; Manickam, Sivakumar
2014-05-12
Multiple emulsions have excellent encapsulating potential and this investigation has been aimed to encapsulate two different plant extracts as functional cosmetic agents in the W/O/W multiple emulsions and the resultant system's long term stability has been determined in the presence of a thickener, hydroxypropyl methylcellulose (HPMC). Multiple W/O/W emulsions have been generated using cetyl dimethicone copolyol as lipophilic emulsifier and a blend of polyoxyethylene (20) cetyl ether and cetomacrogol 1000® as hydrophilic emulsifiers. The generated multiple emulsions have been characterized with conductivity, pH, microscopic analysis, phase separation and rheology for a period of 30 days. Moreover, long term shelf-storage stability has been tested to understand the shelf-life by keeping the generated multiple emulsion formulations at 25 ± 10°C and at 40 ± 10% relative humidity for a period of 12 months. It has been observed that the hydrophilic emulsifiers and HPMC have considerably improved the stability of multiple emulsions for the followed period of 12 months at different storage conditions. These multiple emulsions have shown improved entrapment efficiencies concluded on the release rate of conductometric tracer entrapped in the inner aqueous phase of the multiple emulsions. Multiple emulsions have been found to be stable for a longer period of time with promising characteristics. Hence, stable multiple emulsions loaded with green tea and lotus extracts could be explored for their cosmetic benefits.
77 FR 61515 - Alkyl Amines Polyalkoxylates; Exemption From the Requirement of a Tolerance
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-10
... polyoxyethylene polymers and fatty acids; carriers such as clay and diatomaceous earth; thickeners such as carrageenan and modified cellulose; wetting, spreading, and dispersing agents; propellants in aerosol...
Kadir, R; Stempler, D; Liron, Z; Cohen, S
1989-02-01
A nonionic surfactant, diethyleneglycol lauryl ether (PEG-2-L), increases the flux of either theophylline or adenosine by a factor of 2.2-2.7, when these are delivered from propionic acid solutions into human skin samples, with respect to propionic acid alone. At the same time, the flux of propionic acid from the same vehicles is decreased. Significant expansion of the partial molal volumes vi of both purines occurs following incorporation of PEG-2-L into their propionic acid solution. Hence, the enhancing effect of this surfactant arises mainly from an increase in the excess free energy of these solutes in the donor phase ("push" effect). Paraffin oil increases the flux of either drug from propionic acid by an entirely different mechanism. It enhances the flux of propionic acid into the skin, thus promoting the partitioning of the purine solute in the modified skin barrier ("pull" effect). Indeed, the magnitude of vi of either purine in propionic acid:paraffin oil solution gives no indication of a significant interaction between paraffin oil and the purine solute. Finally, the penetration enhancing effects of PEG-2-L and paraffin oil combined together in the same propionic acid vehicle are additive, resulting in a flux which is approximately the sum total of fluxes obtained separately with PEG-2-L or paraffin oil.
Effect of ethyleneoxide groups of anionic surfactants on lipase activity.
Magalhães, Solange S; Alves, Luís; Sebastião, Marco; Medronho, Bruno; Almeida, Zaida L; Faria, Tiago Q; Brito, Rui M M; Moreno, Maria J; Antunes, Filipe E
2016-09-01
The use of enzymes in laundry and dish detergent products is growing. Such tendency implies dedicated studies to understand surfactant-enzyme interactions. The interactions between surfactants and enzymes and their impact on the catalytic efficiency represent a central problem and were here evaluated using circular dichroism, dynamic light scattering, and enzyme activity determinations. This work focuses on this key issue by evaluating the role of the ethyleneoxide (EO) groups of anionic surfactants on the structure and activity of a commercial lipase, and by focusing on the protein/surfactant interactions at a molecular level. The conformational changes and enzymatic activity of the protein were evaluated in the presence of sodium dodecyl sulfate (SDS also denoted as SLE 0 S) and of sodium lauryl ether sulfate with two EO units (SLE 2 S). The results strongly suggest that the presence of EO units in the surfactant polar headgroup determines the stability and the activity of the enzyme. While SDS promotes enzyme denaturation and consequent loss of activity, SLE 2 S preserves the enzyme structure and activity. The data further highlights that the electrostatic interactions among the protein groups are changed by the presence of the adsorbed anionic surfactants being such absorption mainly driven by hydrophobic interactions. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1276-1282, 2016. © 2016 American Institute of Chemical Engineers.
Effects of addition of sodium lauryl sulfate on frozen-thawed canine spermatozoa.
Hori, Tatsuya; Kaseki, Hanae; Fukuhara, Youko; Oba, Hiromichi; Mizutani, Tatsuji; Kawakami, Eiichi; Tsutsui, Toshihiko
2006-10-01
The addition of Orvus ES paste (OEP) to extender may be essential for preparing frozen dog semen. The major ingredient of OEP is sodium lauryl sulfate (SLS). In this study, we compared the effect of SLS on frozen dog semen with that of OEP. There were no significant differences between the 2-mg/ml SLS group and OEP group concerning sperm motility, viability and the percentage of viable sperm with intact acrosomes after freeze-thawing. These results suggest that the effectiveness of frozen dog semen extender containing 2 mg/ml of SLS is similar effective to that demonstrated for OEP.
Rhodamine-123: a p-glycoprotein marker complex with sodium lauryl sulfate.
Al-Mohizea, Abdullah M; Al-Jenoobi, Fahad Ibrahim; Alam, Mohd Aftab
2015-03-01
Aim of this study was to investigate the role of sodium lauryl sulfate (SLS) as P-glycoprotein inhibitor. The everted rat gut sac model was used to study in-vitro mucosal to serosal transport of Rhodamine-123 (Rho-123). Surprisingly, SLS decreases the serosal absorption of Rho-123 at all investigated concentrations. Investigation reveals complex formation between Rhodamine-123 and sodium lauryl sulfate. Interaction profile of SLS & Rho-123 was studied at variable SLS concentrations. The SLS concentration higher than critical micelle concentration (CMC) increases the solubility of Rho-123 but could not help in serosal absorption, on the contrary the absorption of Rho-123 decreased. Rho-123 and SLS form pink color complex at sub-CMC. The SLS concentrations below CMC decrease the solubility of Rho-123. For further studies, Rho-123 & SLS complex was prepared by using solvent evaporation technique and characterized by using differential scanning calorimeter (DSC). Thermal analysis also proved the formation of complex between SLS & Rho-123. The P values were found to be significant (<0.05) except group comprising 0.0001% SLS, and that is because 0.0001% SLS is seems to be very low to affect the solubility or complexation of Rho-123.
Piccirilli, Gisela N; García, Agustina; Leonardi, Darío; Mamprin, María E; Bolmaro, Raúl E; Salomón, Claudio J; Lamas, María C
2014-11-01
Encapsulation of albendazole, a class II compound, into polymeric microparticles based on chitosan-sodium lauryl sulfate was investigated as a strategy to improve drug dissolution and oral bioavailability. The microparticles were prepared by spray drying technique and further characterized by means of X-ray powder diffractometry, infrared spectroscopy and scanning electron microscopy. The formation of a novel polymeric structure between chitosan and sodium lauryl sulfate, after the internal or external gelation process, was observed by infrared spectroscopy. The efficiency of encapsulation was found to be between 60 and 85% depending on the internal or external gelation process. Almost spherically spray dried microparticles were observed using scanning electron microscopy. In vitro dissolution results indicated that the microparticles prepared by internal gelation released 8% of the drug within 30 min, while the microparticles prepared by external gelation released 67% within 30 min. It was observed that the AUC and Cmax values of ABZ from microparticles were greatly improved, in comparison with the non-encapsulated drug. In conclusion, the release properties and oral bioavailability of albendazole were greatly improved by using spraydried chitosan-sodium lauryl sulphate microparticles.
1980-01-01
In a multi-laboratory trial with the membrane filtration technique, three surfactants--Teepol 610 (T610), Tergitol 7 (T7) and sodium lauryl sulphate (LS)--were compared in media for the enumeration of coliform organisms and Escherichia coli in water. A total of 179 samples of water (87 raw and 92 marginally chlorinated) were examined for colony counts of coliform organisms, and 185 water samples (94 raw and 91 marginally chlorinated) for E. coli. Slight differences in the confirmed colony counts between the three media were noted, but few of these were observed consistently in every laboratory. In most laboratories, T7 gave slightly higher counts of E. coli than LS with chlorinated waters; a higher incidence of false-positive results for E. coli at 44 degrees C was also noted with T7. As there were no outstanding differences in the trial, sodium lauryl sulphate, which is chemically defined, cheap and readily available, is therefore recommended for use at a concentration of 0 . 1% instead of Teepol 610 in the standard medium for the enumeration of coliform organisms and E. coli in water by the membrane filtration technique. PMID:7005324
40 CFR 180.1022 - Iodine-detergent complex; exemption from the requirement of a tolerance.
Code of Federal Regulations, 2014 CFR
2014-07-01
... the surfactants (a) polyoxypropylene-polyoxyethylene glycol nomionic block polymers (minimum average... molecular weight of 748 and in which the nonyl group is a propylene trimer isomer, is exempted from the...
40 CFR 180.1022 - Iodine-detergent complex; exemption from the requirement of a tolerance.
Code of Federal Regulations, 2013 CFR
2013-07-01
... the surfactants (a) polyoxypropylene-polyoxyethylene glycol nomionic block polymers (minimum average... molecular weight of 748 and in which the nonyl group is a propylene trimer isomer, is exempted from the...
40 CFR 180.1022 - Iodine-detergent complex; exemption from the requirement of a tolerance.
Code of Federal Regulations, 2012 CFR
2012-07-01
... the surfactants (a) polyoxypropylene-polyoxyethylene glycol nomionic block polymers (minimum average... molecular weight of 748 and in which the nonyl group is a propylene trimer isomer, is exempted from the...
78 FR 8513 - Product Cancellation Order for Certain Pesticide Registrations
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-06
...) Granular Concentrate. ethylene(dimethylimino)ethylene dichloride). 004787-00036 Glyfos Au Herbicide...-dimethyl, chloride. 045309-00010 Aqua Clear Algae Preventative.... Poly(oxyethylene(dimethylimino) ethylene(dimethylimino)ethylene dichloride). 045309-00011 Spa Clear Non-Foaming Algaecide.. Poly(oxyethylene...
Maswal, Masrat; Dar, Aijaz Ahmad
2013-06-15
Citral is a flavour component widely used in food and cosmetic industries, but is chemically unstable and degrades over time in aqueous solutions due to acid-catalysed and oxidative reactions leading to loss of desirable flavour. The present study reveals the effect of non-ionic micellar solutions of Brij30 and Brij35 on the extent of solubilisation and stabilisation of citral. The rate of chemical degradation of citral in acidic aqueous solutions was found to be highest, which was subsequently reduced significantly within these studied surfactant systems, suggesting protection of citral from an acidic environment once it is incorporated into the micelles. The work concludes that polyoxyethylene alkylether surfactants with lower HLB value, less dense hydrophilic corona and more hydrophobic core volume are efficient in solubilising and stabilising citral against an acidic environment. Copyright © 2012 Elsevier Ltd. All rights reserved.
The solubilization of dodecane by polyoxyethylene (20) sorbitan monooleate, a nonionic surfactant, was investigated as a potential means of recoveringnonaqueous-phase liquids from contaminated aquifers. Residual saturations of dodecane were established by injecting 14C...
Dissolution and solubility behavior of fenofibrate in sodium lauryl sulfate solutions.
Granero, Gladys E; Ramachandran, Chandrasekharan; Amidon, Gordon L
2005-10-01
The solubility of fenofibrate in pH 6.8 McIlvaine buffers containing varying concentrations of sodium lauryl sulfate was determined. The dissolution behavior of fenofibrate was also examined in the same solutions with rotating disk experiments. It was observed that the enhancement in intrinsic dissolution rate was approximately 500-fold and the enhancement in solubility was approximately 2000-fold in a pH 6.8 buffer containing 2% (w/v) sodium lauryl sulfate compared to that in buffer alone. The micellar solubilization equilibrium coefficient (k*) was estimated from the solubility data and found to be 30884+/-213 L/mol. The diffusivity for the free solute, 7.15x10(-6) cm2/s, was calculated using Schroeder's additive molal volume estimates and Hayduk-Laurie correlation. The diffusivity of the drug-loaded micelle, estimated from the experimental solubility and dissolution data and the calculated value for free solute diffusivity, was 0.86x10(-6) cm2/s. Thus, the much lower enhancement in dissolution of fenofibrate compared to its enhancement in solubility in surfactant solutions appears to be consistent with the contribution to the total transport due to enhanced micellar solubilization as well as a large decrease (approximately 8-fold) in the diffusivity of the drug-loaded micelle.
Oral Sustained Release of a Hydrophilic Drug Using the Lauryl Sulfate Salt/Complex.
Kasashima, Yuuki; Yoshihara, Keiichi; Yasuji, Takehiko; Sako, Kazuhiro; Uchida, Shinya; Namiki, Noriyuki
2016-01-01
The objective of this study was to establish the key factor of the lauryl sulfate (LS) salt/complex for sustained release of a hydrophilic drug at various physiological pH levels. Mirabegron is a hydrophilic drug that exhibits pH-dependent solubility. Sodium lauryl sulfate (SLS) bound to mirabegron in a stoichiometric manner. The formation of the LS salt/complex significantly reduced mirabegron solubility and helped achieve sustained release of mirabegron over a wide range of pH levels. In addition to SLS, other additives containing a sulfate group formed salts/complexes with mirabegron and reduced its solubility at different pH levels. Furthermore, octyl sulfate (OS), myristyl sulfate (MS), and cetyl sulfate (CS) salts/complexes, which contain alkyl chains of different lengths, showed a lower solubility than mirabegron and promoted sustained release of mirabegron. The rank order of solubility and dissolution rate were as follows: OS salt/complex>LS salt/complex>MS salt/complex>CS salt/complex, which corresponded to the rank of alkyl chain lengths. We conclude that the presence of a sulfate group and the length of the alkyl chain are key factors of the LS salt/complex for sustained release of a hydrophilic drug at various physiological pH levels.
Shelate, Pragna; Dave, Divyang
2016-01-01
The objective of this work was design, characterization, and optimization of controlled drug delivery system containing antibiotic drug/s. Osmotic drug delivery system was chosen as controlled drug delivery system. The porous osmotic pump tablets were designed using Plackett-Burman and Box-Behnken factorial design to find out the best formulation. For screening of three categories of polymers, six independent variables were chosen for Plackett-Burman design. Osmotic agent sodium chloride and microcrystalline cellulose, pore forming agent sodium lauryl sulphate and sucrose, and coating agent ethyl cellulose and cellulose acetate were chosen as independent variables. Optimization of osmotic tablets was done by Box-Behnken design by selecting three independent variables. Osmotic agent sodium chloride, pore forming agent sodium lauryl sulphate, and coating agent cellulose acetate were chosen as independent variables. The result of Plackett-Burman and Box-Behnken design and ANOVA studies revealed that osmotic agent and pore former had significant effect on the drug release up to 12 hr. The observed independent variables were found to be very close to predicted values of most satisfactory formulation which demonstrates the feasibility of the optimization procedure in successful development of porous osmotic pump tablets containing antibiotic drug/s by using sodium chloride, sodium lauryl sulphate, and cellulose acetate as key excipients. PMID:27610247
Dasgupta, Sudip; Bandyopadhyay, Amit; Bose, Susmita
2009-10-01
Calcium phosphate (CaP) nanoparticles with a calcium to phosphorus (Ca:P) molar ratio of 1.5:1 were synthesized using reverse microemulsion. Ca(NO(3))(2).4H(2)O and H(3)PO(4) were used as the aqueous phase, cyclohexane as the organic phase and poly(oxyethylene)(12) nonylphenol ether (NP-12) as the surfactant. Depending on the calcination temperature between 600 and 800 degrees C, CaP nanoparticle showed different phases of calcium-deficient hydroxyapatite (CDHA) and beta-tricalcium phosphate (beta-TCP), particle size between 48 and 69 nm, and a BET specific average surface area between 73 and 57 m(2)g(-1). Bovine serum albumin (BSA) was used as a model protein to study loading and release behavior. The adsorptive property of BSA was investigated by the change in BET surface area of these nanoparticles and the pH of the suspension. At pH 7.5, the maximum amount of BSA was adsorbed onto CaP nanoparticle. The release kinetics of BSA showed a gradual time-dependent increase in pH 4.0 and 6.0 buffer solutions. However, the amount of protein released was significantly smaller at pH 7.2. The BSA release rate also varied depending on the presence of different phases of CaPs in the system, beta-TCP or CDHA. These results suggest that the BSA protein release rate can be controlled by changing the particle size, surface area and phase composition of the CaP nanocarriers.
2014-01-01
Background and aims Multiple emulsions have excellent encapsulating potential and this investigation has been aimed to encapsulate two different plant extracts as functional cosmetic agents in the W/O/W multiple emulsions and the resultant system’s long term stability has been determined in the presence of a thickener, hydroxypropyl methylcellulose (HPMC). Methods Multiple W/O/W emulsions have been generated using cetyl dimethicone copolyol as lipophilic emulsifier and a blend of polyoxyethylene (20) cetyl ether and cetomacrogol 1000® as hydrophilic emulsifiers. The generated multiple emulsions have been characterized with conductivity, pH, microscopic analysis, phase separation and rheology for a period of 30 days. Moreover, long term shelf-storage stability has been tested to understand the shelf-life by keeping the generated multiple emulsion formulations at 25 ± 10°C and at 40 ± 10% relative humidity for a period of 12 months. Results It has been observed that the hydrophilic emulsifiers and HPMC have considerably improved the stability of multiple emulsions for the followed period of 12 months at different storage conditions. These multiple emulsions have shown improved entrapment efficiencies concluded on the release rate of conductometric tracer entrapped in the inner aqueous phase of the multiple emulsions. Conclusion Multiple emulsions have been found to be stable for a longer period of time with promising characteristics. Hence, stable multiple emulsions loaded with green tea and lotus extracts could be explored for their cosmetic benefits. PMID:24885994
Formulation and in vitro assessment of minoxidil niosomes for enhanced skin delivery.
Balakrishnan, Prabagar; Shanmugam, Srinivasan; Lee, Won Seok; Lee, Won Mo; Kim, Jong Oh; Oh, Dong Hoon; Kim, Dae-Duk; Kim, Jung Sun; Yoo, Bong Kyu; Choi, Han-Gon; Woo, Jong Soo; Yong, Chul Soon
2009-07-30
Niosomes have been reported as a possible approach to improve the low skin penetration and bioavailability characteristics shown by conventional topical vehicle for minoxidil. Niosomes formed from polyoxyethylene alkyl ethers (Brij) or sorbitan monoesters (Span) with cholesterol molar ratios of 0, 1 and 1.5 were prepared with varying drug amount 20-50mg using thin film-hydration method. The prepared systems were characterized for entrapment efficiency, particle size, zeta potential and stability. Skin permeation studies were performed using static vertical diffusion Franz cells and hairless mouse skin treated with either niosomes, control minoxidil solution (propylene glycol-water-ethanol at 20:30:50, v/v/v) or a leading topical minoxidil commercial formulation (Minoxyl). The results showed that the type of surfactant, cholesterol and incorporated amount of drug altered the entrapment efficiency of niosomes. Higher entrapment efficiency was obtained with the niosomes prepared from Span 60 and cholesterol at 1:1 molar ratio using 25mg drug. Niosomal formulations have shown a fairly high retention of minoxidil inside the vesicles (80%) at refrigerated temperature up to a period of 3 months. It was observed that both dialyzed and non-dialyzed niosomal formulations (1.03+/-0.18 to 19.41+/-4.04%) enhanced the percentage of dose accumulated in the skin compared to commercial and control formulations (0.11+/-0.03 to 0.48+/-0.17%) except dialyzed Span 60 niosomes. The greatest skin accumulation was always obtained with non-dialyzed vesicular formulations. Our results suggest that these niosomal formulations could constitute a promising approach for the topical delivery of minoxidil in hair loss treatment.
Zhang, Lei; Li, Bao; Xia, Yangchao; Liu, Shengyu
2017-09-01
Lignite is an important and useful fossil fuel in the world and the strong hydrophilicity of it limits its applications. Surfactant adsorption on lignite is an effective way to make it hydrophobic. In this work, aiming to examine the effect of the degree of ethoxylation on the adsorption behavior of dodecyl poly ethoxylated surfactants on lignite and the wettability modification of modified lignite by surfactant adsorption, different combined systems formed by surfactants, water and a model surface of Wender lignite have been studied using molecular dynamics simulation. The adsorption configurations vary with the degree of ethoxylation. At the same adsorption amounts, increasing the degree of ethoxylation can make the adsorption layer more compactness and bring stronger adsorption strength. The results of binding energy and its components show that the adsorption of alkyl polyoxyethylene ethers surfactant on lignite is physically adsorbed rather than electrostatically or chemisorbed. Meanwhile, van der Waals interaction plays a dominant role in the adsorption. The addition of surfactant could reduce the possibility of the interaction between water and lignite. Compared to the original lignite, the interaction between them is weakened after surfactant adsorption in water/surfactant/lignite system, thus strengthening the hydrophobicity of lignite. Similar to the adsorption strength, hydrophobicity of modified lignite increases with the increase of the degree of ethoxylation. The lignite surface properties are changed due to surfactant adsorption by analyzing the compositions of interaction energy and the change of hydrogen bonds. Copyright © 2017 Elsevier Inc. All rights reserved.
Suh, D H; Youn, J I; Eun, H C
2001-11-01
Skin aging may be divided into photoaging and intrinsic aging. The purpose of this study was to investigate the effects of 12-O-tetradecanoyl-phorbol-13-acetate and sodium lauryl sulfate on the production and expression of cytokines and proto-oncogenes in photoaged and intrinsically aged skin, compared with young skin. Keratinocytes were taken from newborns, young adults in their twenties, and from the forearm and thigh of volunteers in their fifties and seventies. Interleukin-1alpha and -6, and interleukin-1 receptor antagonist, c-fos and c-myc were measured after cultured keratinocytes had been treated with 12-O-tetradecanoyl-phorbol-13-acetate and sodium lauryl sulfate. There has been no report concerning the dependence of cytokine production by sodium lauryl sulfate upon photoaging and intrinsic aging. This study also involves the first investigation of the effects of aging on c-myc expression by 12-O-tetradecanoyl-phorbol-13-acetate treatment. Cytokine production decreased markedly with age. These results suggest the progressive decline of cellular function with age. The ratio of cytokine production in the irritant-treated group compared with that in the control group showed a different pattern in photoaging and intrinsic aging. With the significant difference between photoaging and intrinsic aging, T/C ratio decreased in interleukin-1alpha and interleukin-1 receptor antagonist upon aging, whereas it increased in interleukin-6. S/C ratio was uniquely elevated on photoaged skin in the 50 y age group. It is suggested that photoaged skin shows an exaggerated reaction to surfactant. Compared with the control, c-fos expression in 12-O-tetradecanoyl-phorbol-13-acetate-treated keratinocytes decreased with age in the thigh, but increased in the photoaged skin of forearm. The increased c-fos expression in 12-O-tetradecanoyl-phorbol-13-acetate-treated keratinocytes could be relevant for the predisposition of photoaged keratinocytes to malignant transformation.
Inert Reassessment Document for Poly(oxyethylene) adducts of mixed phytosterols
Poly(oxyethy1ene) adducts of mixed phytosterols is uncategorized as to list classification status. Based upon the reasonable certainty of no harm safety finding, the List 4B classification for poly(oxyethy1ene) adducts of mixed phytosterols is affirmed.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-18
... alcohols and hydrocarbons; surfactants such as polyoxyethylene polymers and fatty acids; carriers such as... NAPAAS primary amines and primary amine acetate salt may also be conjugated, whether by glucuronidation...
Yutani, Reiko; Teraoka, Reiko; Kitagawa, Shuji
2015-01-01
We examined the phase behavior of various polyoxyethylene sorbitan fatty acid ester (polysorbates)/ethanol/isopropyl myristate (IPM)/150 mM NaCl solution (NaClaq) systems in order to prepare a microemulsion containing a low ratio of ethanol, which is more suitable for in vivo application. Using polyoxyethylene sorbitan trioleate (Tween 85), which has a large lipophilic moiety, as a surfactant component, single-phase domain of the phase diagram was the largest of all the polysorbates examined, and in particular a large oil-rich single-phase domain was obtained. When the ratio of Tween 85 to ethanol was changed from 1 : 1 to 3 : 1, the oil-rich single-phase domain further expanded, which led to a reduced ethanol concentration in the preparation. Thus, we determined the composition of the microemulsion to be Tween 85 : ethanol : IPM : NaClaq=30 : 10 : 53 : 7, and used it for skin delivery of resveratrol. Microemulsion gel was also prepared by adding 6.5% Aerosil) 200 into the microemulsion for ease of topical application. When applied with each vehicle, delivery of resveratrol into guinea pig skin in vitro was significantly enhanced compared with that by IPM, and resveratrol incorporated into the skin by microemulsion gel decreased lipid peroxidation to 29.5% compared with that of the control. Pretreatment of guinea pig dorsal skin with the microemulsion gel containing resveratrol almost completely prevented UV-B-induced erythema formation in vivo. These findings demonstrate that the microemulsion using Tween 85 containing a minimal concentration of ethanol enhanced the skin delivery of resveratrol and the incorporated resveratrol exhibited a protective effect against UV-induced oxidative damage.
Carricajo, A.; Fonsale, N.; Vautrin, A. C.; Aubert, G.
2001-01-01
A total of 52 mycobacterial isolates were recovered from 1,197 clinical specimens decontaminated by a sodium dodecyl (lauryl) sulfate (SDS)-NaOH protocol. Of these, 94% were recovered with the BacT/Alert 3D system (Organon Teknika, Durham, N.C.) and 79% were recovered on Löwenstein-Jensen (LJ) medium. Mean times to detection of organisms of the Mycobacterium tuberculosis complex (n = 47) were 22.8 days with LJ medium and 16.2 days with the system. The BacT/Alert 3D system is a rapid and efficient detection system which can be used with an SDS-NaOH decontamination procedure. PMID:11574623
Elsayed, Amani; Al-Remawi, Mayyas; Qinna, Nidal; Farouk, Asim; Al-Sou'od, Khaldoun A; Badwan, Adnan A
2011-09-01
The present work explores the possibility of formulating an oral insulin delivery system using nanoparticulate complexes made from the interaction between biodegradable, natural polymer called chitosan and anionic surfactant called sodium lauryl sulfate (SLS). The interaction between chitosan and SLS was confirmed by Fourier transform infrared spectroscopy. The nanoparticles were prepared by simple gelation method under aqueous-based conditions. The nanoparticles were stable in simulated gastric fluids and could protect the encapsulated insulin from the GIT enzymes. Additionally, the in vivo results clearly indicated that the insulin-loaded nanoparticles could effectively reduce the blood glucose level in a diabetic rat model. However, additional formulation modifications are required to improve insulin oral bioavailability.
NASA Astrophysics Data System (ADS)
Wijayati, N.; Masubah, K.; Supartono
2017-02-01
Lipase is an enzyme with large biotechnology applications, such as hydrolysis in the food industry, applications in chemical industry, synthesis of polymers and surfactants. Lipase was isolated from oyster mushroom with activity 0,93 U/mg and protein content 1,1234 mg/mL. Lipase was immobilized by entrapment method in a matrix of Ca-alginate. This report describes that we have developed for the synthesis of lauryl diethanolamide The result showed that the optimum condition of lipase immobilization was achieved on 3% Na-alginate solution with protein content 0,84 mg/mL and the activity 3,33 U/mg. An amide (22.911%) formed from the amidation of lauric acid and diethanolamine.
Foam-assisted delivery of nanoscale zero valent iron in porous media
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ding, Yuanzhao; Liu, Bo; Shen, Xin
2013-09-01
Foam is potentially a promising vehicle to deliver nanoparticles for vadose zone remediation as foam can overcome the intrinsic problems associated with solution-based delivery, such as preferential flow and contaminant mobilization. In this work, the feasibility of using foam to deliver nanoscale zero valent iron (nZVI) in unsaturated porous media was investigated. Foams generated using surfactant sodium lauryl ether sulfate (SLES) showed excellent ability to carry nZVI. SLES and nZVI concentrations in the foaming solutions did not affect the percentages of nZVI concentrations in foams relative to nZVI concentrations in the solutions. When foams carrying nZVI were injected through themore » unsaturated columns, the fractions of nZVI exiting the column were much higher than those when nZVI was injected in liquid. The enhanced nZVI transport implies that foam delivery could significantly increase the radius of influence of injected nZVI. The type and concentrations of surfactants and the influent nZVI concentrations did not noticeably affect nZVI transport during foam delivery. In contrast, nZVI retention increased considerably as the grain size of porous media decreased. Oxidation of foam-delivered nZVI due to oxygen diffusion into unsaturated porous media was visually examined using a flow cell. It was demonstrated that if foams are injected to cover a deep vadose zone layer, oxidation would only cause a small fraction of foam-delivered nZVI to be oxidized before it reacts with contaminants.« less
Enhanced Remedial Amendment Delivery to Subsurface Using Shear Thinning Fluid and Aqueous Foam
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhong, Lirong; Szecsody, James E.; Oostrom, Martinus
2011-04-23
A major issue with in situ subsurface remediation is the ability to achieve an even spatial distribution of remedial amendments to the contamination zones in an aquifer or vadose zone. Delivery of amendment to the aquifer using shear thinning fluid and to the vadose zone using aqueous foam has the potential to enhance the amendment distribution into desired locations and improve the remediation. 2-D saturated flow cell experiments were conducted to evaluate the enhanced sweeping, contaminant removal, and amendment persistence achieved by shear thinning fluid delivery. Bio-polymer xanthan gum solution was used as the shear thinning fluid. Unsaturated 1-D columnmore » and 2-D flow cell experiments were conducted to evaluate the mitigation of contaminant mobilization, amendment uniform distribution enhancement, and lateral delivery improvement by foam delivery. Surfactant sodium lauryl ether sulfate was used as the foaming agent. It was demonstrated that the shear thinning fluid injection enhanced the fluid sweeping over a heterogeneous system and increased the delivery of remedial amendment into low-permeability zones. The persistence of the amendment distributed into the low-perm zones by the shear thinning fluid was prolonged compared to that of amendment distributed by water injection. Foam delivery of amendment was shown to mitigate the mobilization of highly mobile contaminant from sediments under vadose zone conditions. Foam delivery also achieved more uniform amendment distribution in a heterogeneous unsaturated system, and demonstrated remarkable increasing in lateral distribution of the injected liquid compared to direct liquid injection.« less
Agishi, T; Funakoshi, Y; Honda, H; Yamagata, K; Kobayashi, M; Takahashi, M
1988-01-01
In order to investigate a new possibility for artificial blood with oxygen-carrying capability to be applied to other than mere supplementation, normothermic whole body rinse-out in which artificial blood deriving from perfluorochemical emulsion, Fluosol-DA 20% (Green Cross Co., Ltd., Osaka, Japan) or stabilized hemoglobin solution, (pyridoxylated hemoglobin)-(polyoxyethylene) conjugate solution (Ajinomoto Co., Ltd., Tokyo, Japan) were used as rinsing fluid for a blood purification experiment. Replacement either with approximately 150 ml/kg of Fluosol-DA or stabilized hemoglobin solution showed effective removal of digoxin at a reduction rate of 96.3% or 92.2%, respectively. However, when Fluosol-DA was used, a certain amount of perfluorochemical should be retrieved by centrifugation to avoid a possible toxic effect on the reticulo-endothelial system. Even though 3 out of 6, and 3 out of 8 dogs, respectively, survived for a long period after the procedure, the experimental dogs were very susceptible to infection.
40 CFR 721.10170 - Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic).
Code of Federal Regulations, 2013 CFR
2013-07-01
... polyalkylarylphenylether sulfate ammonium salt (generic). 721.10170 Section 721.10170 Protection of Environment... polyalkylarylphenylether sulfate ammonium salt (generic). (a) Chemical substance and significant new uses subject to... sulfate ammonium salt (PMN P-03-197) is subject to reporting under this section for the significant new...
40 CFR 721.10170 - Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic).
Code of Federal Regulations, 2012 CFR
2012-07-01
... polyalkylarylphenylether sulfate ammonium salt (generic). 721.10170 Section 721.10170 Protection of Environment... polyalkylarylphenylether sulfate ammonium salt (generic). (a) Chemical substance and significant new uses subject to... sulfate ammonium salt (PMN P-03-197) is subject to reporting under this section for the significant new...
40 CFR 721.10170 - Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic).
Code of Federal Regulations, 2011 CFR
2011-07-01
... polyalkylarylphenylether sulfate ammonium salt (generic). 721.10170 Section 721.10170 Protection of Environment... polyalkylarylphenylether sulfate ammonium salt (generic). (a) Chemical substance and significant new uses subject to... sulfate ammonium salt (PMN P-03-197) is subject to reporting under this section for the significant new...
40 CFR 721.10170 - Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic).
Code of Federal Regulations, 2014 CFR
2014-07-01
... polyalkylarylphenylether sulfate ammonium salt (generic). 721.10170 Section 721.10170 Protection of Environment... polyalkylarylphenylether sulfate ammonium salt (generic). (a) Chemical substance and significant new uses subject to... sulfate ammonium salt (PMN P-03-197) is subject to reporting under this section for the significant new...
40 CFR 721.10170 - Polyoxyethylene polyalkylarylphenylether sulfate ammonium salt (generic).
Code of Federal Regulations, 2010 CFR
2010-07-01
... polyalkylarylphenylether sulfate ammonium salt (generic). 721.10170 Section 721.10170 Protection of Environment... polyalkylarylphenylether sulfate ammonium salt (generic). (a) Chemical substance and significant new uses subject to... sulfate ammonium salt (PMN P-03-197) is subject to reporting under this section for the significant new...
76 FR 6335 - Sodium and Potassium Salts of N-alkyl (C8
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-04
...): Solvents such as alcohols and hydrocarbons; surfactants such as polyoxyethylene polymers and fatty acids... metabolites are not systemically toxic and would be rapidly conjugated and excreted. The SSNA surfactants (mono and di-sodium propionates) may be conjugated and excreted directly. Alternatively, the tertiary...
Uter, Wolfgang; Geier, Johannes; Becker, Detlef; Brasch, Jochen; Löffler, Harald
2004-01-01
In a multicentre study of the German Contact Dermatitis Research Group, sodium lauryl sulfate (SLS) 0.25% and 0.5% aq. has been added to routine allergen patch tests to assess its properties as a convenient diagnostic indicator of individual susceptibility to irritation at the time of patch testing. Previous studies indicated that irritant SLS reactivity may be related to individual factors such as age and sex. As these factors are, in turn, among the important predictors of contact allergy to many allergens, e.g. summarized in the 'MOAHLFA index', the impact of the MOAHLFA factors on irritant SLS patch test reactivity, and thus a potential for confounding, was assessed in the 5971 participating patients. As a result of 2 logistic regression analyses with an irritant reaction to 0.25% and 0.5% SLS, respectively, as outcome, male sex was identified as a relatively weak but significant risk factor (OR 1.38), while age 40 years or older was an even weaker risk factor (OR 1.22 and 1.15, respectively). Upon detailed analysis, no clear age gradient could, however, be identified. 1-day exposure time almost halved the odds of an irritant SLS reaction. In conclusion, this type of SLS patch test can be regarded as robust, indicating individual irritability relatively independent from the individual factors analysed here.
Oral sustained-release suspension based on a lauryl sulfate salt/complex.
Kasashima, Yuuki; Uchida, Shinya; Yoshihara, Keiichi; Yasuji, Takehiko; Sako, Kazuhiro; Namiki, Noriyuki
2016-12-30
The objective of this study was to evaluate the feasibility of lauryl sulfate (LS) salt/complex as a novel carrier in oral sustained-release suspensions. Mirabegron, which has a pH-dependent solubility, was selected as the model drug. Sodium lauryl sulfate (SLS) was bound to mirabegron in a stoichiometric manner to form an LS salt/complex. LS salt/complex formulation significantly reduced the solubility of mirabegron and helped mirabegron achieve sustained-release over a wide range of pH conditions. Microparticles containing the LS salt/complex were prepared by spray drying with the aqueous dispersion of ethylcellulose (Aquacoat ® ECD). The diameter of the microparticles was less than 200μm, which will help avoid a gritty taste. In vitro results indicated the microparticles had slower dissolution profiles than the LS salt/complex. The dissolution rate could be controlled flexibly by changing the amount of Aquacoat ® ECD. The microparticle suspension retained the desired sustained-release property and dissolution profile after being stored for 30days at 40°C. In addition, the suspension displayed sustained-release behavior in dogs without a pronounced C max peak, which will help prevent side effects. These results suggest that microparticles containing LS salt/complex may be useful as a novel sustained-release suspension for oral delivery. Copyright © 2016 Elsevier B.V. All rights reserved.
Lauryl Amine as heavy metal collector of boiler ash from pulp and paper mill waste
NASA Astrophysics Data System (ADS)
Sembiring, M. P.; Kaban, J.; Bangun, N.; Saputra, E.
2018-04-01
Theincreasing of demand of pulp and paper products, will following with the growing the pulp and paper industryand generate significant mill waste. The total waste reached 1/3 of the amount raw materials used and ash boiler is the waste with the largest percentage of 52%. For that it takes effort to manage the existing waste. The boiler ash contained the chemical elements, it can be utilized such as fertilizer, because it also contains transition metals in form of heavy metal such as Cadmium (Cd), Cobalt (Co), Chrome (Cr), Cupprum (Cu), Ferrum (Fe), Nickel (Ni), and Zinc (Zn), the use of boiler ash must follow the threshold specified by the Government. Several studies have been undertaken to reduce and extract heavy metals from ash and sand of the boiler by using carbon dioxide as its ligand. Eelectrochemical method was used to remove and recovery of heavy metals from the incenerator. This study focused on removal of heavy metals using Lauryl Amine as collector and three solvents namely Dichloromethane, Ethanol and n-Hexane. The treatmentswas able to extract the heavy metal and generally reduce the heavy metal content of ash boiler pulp and paper mill waste. The combination treatment used toreduce the heavy metal content of 5 gram Lauryl Amine collector in Dichloromethane solvent for 4 hours process time.
... Sodium lauryl sulfate (SLS), an ingredient in many toothpastes and mouthwashes, has been linked to canker sores, ... you brush your teeth . Brush and rinse with toothpastes and mouthwashes that don't contain SLS. And ...
Corazza, Monica; Virgili, Annarosa
2005-05-01
In patients suspected of allergic contact dermatitis because of topical ophthalmic medicaments, patch tests performed with patients' own products are often negative. The irritant anionic surfactant sodium lauryl sulfate (SLS) may alter the stratum corneum and increase antigen penetration. Pre-treatment of the skin with SLS 0.5% for 24 h was performed in the sites of patch tests with patients' own products in 15 selected patients. In patients previously negative to their own products tested with conventional patch tests, SLS pre-treatment showed 6 new relevant positive reactions and induced a stronger positive reaction in 1 patient. SLS pre-treatment could be proposed as an alternative promising method, which may increase sensitivity of patch tests with patients' own products.
Dai, Wei-Guo; Dong, Liang C
2007-05-04
An insulin/lauryl sulfate complex was prepared by hydrophobic ion pairing (HIP). The physiochemical and biological properties of the HIP complex were characterized using octanol/water partition measurement, isothermal titration calorimetry (ITC), ultraviolet-circular dichroism (UV-CD) and Fourier transform infrared spectroscopy (FTIR). Sodium dodecyl sulfate (SDS) bound to the insulin in a stoichiometric manner. The formed complex exhibited lipophilicity, and its insulin retained its native structure integrity. The in vivo bioactivity of the complex insulin was evaluated in rats by monitoring the plasma glucose level after intravenous (i.v.) injection, and the glucose level was compared with that for free insulin. The pharmacodynamic study result in rats showed that the complex insulin had in vivo bioactivity comparable to free insulin.
β-Glucoside Activators of Mung Bean UDP-Glucose: β-Glucan Synthase 1
Callaghan, Theresa; Ross, Peter; Weinberger-Ohana, Patricia; Benziman, Moshe
1988-01-01
n-Alkyl (C6-C12) β-d-monoglucopyranosides have been found to be highly potent activators of mung bean β-glucan synthase in vitro, increasing the Vmax of the enzyme as much as 60-fold and with Ka values as low as 10 micromolar. Activation is highly specific for the β-linked terminal glucose residue; other alkyl glycosides such as, octyl-α-glucoside, dodecyl β-maltoside, 6-lauryl sucrose, 6-lauryl glucose, which lack this structure, are ineffective as activators. Based on the similarities in their structure and effects on β-glucan synthesis under a variety of conditions, it is proposed that the alkyl β-glucosides are structural analogs of the native glucolipid activator of β-glucan synthase isolated from mung bean extracts. PMID:16666039
Li, Mingzhong; Qiao, Ning; Wang, Ke
2013-10-11
The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine-nicotinamide (CBZ-NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ-NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ-NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ-NIC cocrystal but they had totally opposite effects on the IDR of the CBZ-NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ-NIC cocrystal while Tween 80 decreased its IDR.
Li, Mingzhong; Qiao, Ning; Wang, Ke
2013-01-01
The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine–nicotinamide (CBZ–NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ–NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ–NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ–NIC cocrystal but they had totally opposite effects on the IDR of the CBZ–NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ–NIC cocrystal while Tween 80 decreased its IDR. PMID:24300560
21 CFR 177.1500 - Nylon resins.
Code of Federal Regulations, 2013 CFR
2013-04-01
... condensation of adipic acid, 1,3-benzenedimethanamine, and alpha-(3-aminopropyl)-omega-(3-amino-propoxy)poly- oxyethylene under such conditions that the alpha-(3-amino-propyl)-omega-(3-aminopropoxy) polyoxyethylene... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Nylon resins. 177.1500 Section 177.1500 Food and...
21 CFR 177.1500 - Nylon resins.
Code of Federal Regulations, 2011 CFR
2011-04-01
... condensation of adipic acid, 1,3-benzenedimethanamine, and alpha-(3-aminopropyl)-omega-(3-amino-propoxy)poly- oxyethylene under such conditions that the alpha-(3-amino-propyl)-omega-(3-aminopropoxy) polyoxyethylene... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Nylon resins. 177.1500 Section 177.1500 Food and...
21 CFR 177.1500 - Nylon resins.
Code of Federal Regulations, 2012 CFR
2012-04-01
... condensation of adipic acid, 1,3-benzenedimethanamine, and alpha-(3-aminopropyl)-omega-(3-amino-propoxy)poly- oxyethylene under such conditions that the alpha-(3-amino-propyl)-omega-(3-aminopropoxy) polyoxyethylene... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Nylon resins. 177.1500 Section 177.1500 Food and...
21 CFR 177.1500 - Nylon resins.
Code of Federal Regulations, 2014 CFR
2014-04-01
...-benzenedimethanamine, and alpha-(3-aminopropyl)-omega-(3-amino-propoxy)poly- oxyethylene under such conditions that the alpha-(3-amino-propyl)-omega-(3-aminopropoxy) polyoxyethylene monomer content does not exceed 7 percent... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Nylon resins. 177.1500 Section 177.1500 Food and...
21 CFR 177.1500 - Nylon resins.
Code of Federal Regulations, 2010 CFR
2010-04-01
... condensation of adipic acid, 1,3-benzenedimethanamine, and alpha-(3-aminopropyl)-omega-(3-amino-propoxy)poly- oxyethylene under such conditions that the alpha-(3-amino-propyl)-omega-(3-aminopropoxy) polyoxyethylene... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Nylon resins. 177.1500 Section 177.1500 Food and...
21 CFR 573.840 - Polysorbate 60.
Code of Federal Regulations, 2012 CFR
2012-04-01
..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.840 Polysorbate 60. The food additive polysorbate 60 (polyoxyethylene (20) sorbitan... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Polysorbate 60. 573.840 Section 573.840 Food and...
21 CFR 573.860 - Polysorbate 80.
Code of Federal Regulations, 2013 CFR
2013-04-01
..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.860 Polysorbate 80. The food additive polysorbate 80 (polyoxyethylene (20) sorbitan... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Polysorbate 80. 573.860 Section 573.860 Food and...
21 CFR 573.840 - Polysorbate 60.
Code of Federal Regulations, 2010 CFR
2010-04-01
..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.840 Polysorbate 60. The food additive polysorbate 60 (polyoxyethylene (20) sorbitan... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Polysorbate 60. 573.840 Section 573.840 Food and...
21 CFR 573.840 - Polysorbate 60.
Code of Federal Regulations, 2011 CFR
2011-04-01
..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.840 Polysorbate 60. The food additive polysorbate 60 (polyoxyethylene (20) sorbitan... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Polysorbate 60. 573.840 Section 573.840 Food and...
21 CFR 573.860 - Polysorbate 80.
Code of Federal Regulations, 2012 CFR
2012-04-01
..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.860 Polysorbate 80. The food additive polysorbate 80 (polyoxyethylene (20) sorbitan... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Polysorbate 80. 573.860 Section 573.860 Food and...
21 CFR 573.860 - Polysorbate 80.
Code of Federal Regulations, 2014 CFR
2014-04-01
..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.860 Polysorbate 80. The food additive polysorbate 80 (polyoxyethylene (20) sorbitan... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Polysorbate 80. 573.860 Section 573.860 Food and...
21 CFR 573.860 - Polysorbate 80.
Code of Federal Regulations, 2011 CFR
2011-04-01
..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.860 Polysorbate 80. The food additive polysorbate 80 (polyoxyethylene (20) sorbitan... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Polysorbate 80. 573.860 Section 573.860 Food and...
21 CFR 573.840 - Polysorbate 60.
Code of Federal Regulations, 2014 CFR
2014-04-01
..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.840 Polysorbate 60. The food additive polysorbate 60 (polyoxyethylene (20) sorbitan... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Polysorbate 60. 573.840 Section 573.840 Food and...
21 CFR 573.860 - Polysorbate 80.
Code of Federal Regulations, 2010 CFR
2010-04-01
..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.860 Polysorbate 80. The food additive polysorbate 80 (polyoxyethylene (20) sorbitan... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Polysorbate 80. 573.860 Section 573.860 Food and...
21 CFR 573.840 - Polysorbate 60.
Code of Federal Regulations, 2013 CFR
2013-04-01
..., FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.840 Polysorbate 60. The food additive polysorbate 60 (polyoxyethylene (20) sorbitan... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Polysorbate 60. 573.840 Section 573.840 Food and...
40 CFR 180.960 - Polymers; exemptions from the requirement of a tolerance.
Code of Federal Regulations, 2014 CFR
2014-07-01
...-hydroxypoly (oxypropylene) and/or poly (oxyethylene) polymers where the alkyl chain contains a minimum of six...-hydroxypoly(oxyethylene)poly (oxypropylene) poly(oxyethylene) block copolymer; the minimum poly(oxypropylene... weight (in amu), 900,000 62386-95-2 Monophosphate ester of the block copolymer α-hydro-ω-hydroxypoly...
Micelle Catalysis of an Aromatic Substitution Reaction
ERIC Educational Resources Information Center
Corsaro, Gerald; Smith J. K.
1976-01-01
Describes an experiment in which the iodonation of aniline reaction is shown to undergo catalysis in solution of sodium lauryl sulfate which forms micelles with negatively charged pseudo surfaces. (MLH)
Bardhan, Soumik; Kundu, Kaushik; Saha, Swapan K; Paul, Bidyut K
2013-12-01
In this contribution, we report on a systematic investigation of phase behavior and solubilization of water in water-in-heptane or decane aggregates stabilized by mixtures of polyoxyethylene (20) cetyl ether (Brij-58) and cetyltrimethylammonium bromide (CTAB) surfactants with varying compositions in conjugation with 1-pentanol (Pn) at fixed surfactant(s)/Pn ratio and temperature. Synergism in water solubilization was evidenced by the addition of CTAB to Brij-58 stabilized system in close proximity of equimolar composition in both oils. An attempt has been made to correlate composition dependent water solubilization and volume induced conductivity studies to provide insight into the solubilization mechanism of these mixed systems. Conductivity studies reveal the ascending curve in water solubilization capacity-(Brij-58:CTAB, w/w) profile as the interdroplet interaction branch indicating percolation of conductance and the descending curve is a curvature branch due to the rigidity of the interface in these systems. The microstructure of these systems as a function of surfactant composition has been determined by dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FTIR) measurements. FTIR study reveals increase and decrease in relative population of bound and bulk-like water, respectively, with increase in Brij-58:CTAB (w/w). DLS measurements showed that the droplet hydrodynamic diameter (Dh) decreases significantly with the increase in Brij-58:CTAB (w/w). Further, the interfacial composition and energetic parameters for the transfer of Pn from bulk oil to the interface were evaluated by the dilution method. Formation of temperature-insensitive microemulsions and temperature invariant droplet sizes are evidenced in the vicinity of the equimolar composition. The results are interpreted in terms of a proposed mechanism. Copyright © 2013 Elsevier Inc. All rights reserved.
Gürkan, Ramazan; Korkmaz, Sema; Altunay, Nail
2016-08-01
A new ultrasonic-thermostatic-assisted cloud point extraction procedure (UTA-CPE) was developed for preconcentration at the trace levels of vanadium (V) and molybdenum (Mo) in milk, vegetables and foodstuffs prior to determination via flame atomic absorption spectrometry (FAAS). The method is based on the ion-association of stable anionic oxalate complexes of V(V) and Mo(VI) with [9-(diethylamino)benzo[a]phenoxazin-5-ylidene]azanium; sulfate (Nile blue A) at pH 4.5, and then extraction of the formed ion-association complexes into micellar phase of polyoxyethylene(7.5)nonylphenyl ether (PONPE 7.5). The UTA-CPE is greatly simplified and accelerated compared to traditional cloud point extraction (CPE). The analytical parameters optimized are solution pH, the concentrations of complexing reagents (oxalate and Nile blue A), the PONPE 7.5 concentration, electrolyte concentration, sample volume, temperature and ultrasonic power. Under the optimum conditions, the calibration curves for Mo(VI) and V(V) are obtained in the concentration range of 3-340µgL(-1) and 5-250µgL(-1) with high sensitivity enhancement factors (EFs) of 145 and 115, respectively. The limits of detection (LODs) for Mo(VI) and V(V) are 0.86 and 1.55µgL(-1), respectively. The proposed method demonstrated good performances such as relative standard deviations (as RSD %) (≤3.5%) and spiked recoveries (95.7-102.3%). The accuracy of the method was assessed by analysis of two standard reference materials (SRMs) and recoveries of spiked solutions. The method was successfully applied into the determination of trace amounts of Mo(VI) and V(V) in milk, vegetables and foodstuffs with satisfactory results. Copyright © 2016 Elsevier B.V. All rights reserved.
Calderó, G; Montes, R; Llinàs, M; García-Celma, M J; Porras, M; Solans, C
2016-09-01
Ethylcellulose nanoparticles have been obtained from O/W nano-emulsions of the water/polyoxyethylene 10 oleyl ether/[ethyl acetate+4wt% ethylcellulose] system by low energy-energy emulsification at 25°C. Nano-emulsions with droplet sizes below 200nm and high kinetic stability were chosen for solubilising dexamethasone (DXM). Phase behaviour, conductivity and optical analysis studies of the system have evidenced for the first time that both, the polymer and the drug play a role on the structure of the aggregates formed along the emulsification path. Nano-emulsion formation may take place by both, phase inversion and self-emulsification. Spherical polymeric nanoparticles containing surfactant, showing sizes below 160nm have been obtained from the nano-emulsions by organic solvent evaporation. DXM loading in the nanoparticles was high (>90%). The release kinetics of nanoparticle dispersions with similar particle size and encapsulated DXM but different polymer to surfactant ratio were studied and compared to an aqueous DXM solution. Drug release from the nanoparticle dispersions was slower than from the aqueous solution. While the DXM solution showed a Fickian release pattern, the release behaviour from the nanoparticle dispersions was faster than that expected from a pure Fickian release. A coupled diffusion/relaxation model fitted the results very well, suggesting that polymer chains undergo conformational changes enhancing drug release. The contribution of diffusion and relaxation to drug transport in the nanoparticle dispersions depended on their composition and release time. Surfactant micelles present in the nanoparticle dispersion may exert a mild reservoir effect. The small particle size and the prolonged DXM release provided by the ethylcellulose nanoparticle dispersions make them suitable vehicles for controlled drug delivery applications. Copyright © 2016 Elsevier B.V. All rights reserved.
Klammt, Christian; Schwarz, Daniel; Fendler, Klaus; Haase, Winfried; Dötsch, Volker; Bernhard, Frank
2005-12-01
Cell-free expression has become a highly promising tool for the fast and efficient production of integral membrane proteins. The proteins can be produced as precipitates that solubilize in mild detergents usually without any prior denaturation steps. Alternatively, membrane proteins can be synthesized in a soluble form by adding detergents to the cell-free system. However, the effects of a representative variety of detergents on the production, solubility and activity of a wider range of membrane proteins upon cell-free expression are currently unknown. We therefore analyzed the cell-free expression of three structurally very different membrane proteins, namely the bacterial alpha-helical multidrug transporter, EmrE, the beta-barrel nucleoside transporter, Tsx, and the porcine vasopressin receptor of the eukaryotic superfamily of G-protein coupled receptors. All three membrane proteins could be produced in amounts of several mg per one ml of reaction mixture. In general, the detergent 1-myristoyl-2-hydroxy-sn-glycero-3-[phospho-rac-(1-glycerol)] was found to be most effective for the resolubilization of membrane protein precipitates, while long chain polyoxyethylene-alkyl-ethers proved to be most suitable for the soluble expression of all three types of membrane proteins. The yield of soluble expressed membrane protein remained relatively stable above a certain threshold concentration of the detergents. We report, for the first time, the high-level cell-free expression of a beta-barrel type membrane protein in a functional form. Structural and functional variations of the analyzed membrane proteins are evident that correspond with the mode of expression and that depend on the supplied detergent.
Terpenoid biosynthesis in Euphorbia lathyris and Copaifera spp
DOE Office of Scientific and Technical Information (OSTI.GOV)
Skrukrud, C.L.
1987-07-01
Biosynthesis of triterpenoids by isolated latex of Euphorbia lathyris was investigated. The rate of in vitro incorporation of mevalonic acid into triterpenoids was thirty times greater than acetate incorporation indicating that the rate-limiting step in the pathway occurs prior to mevalonate. Both HMG-CoA reductase (EC 1.1.1.34) and HMG-CoA lyase (EC 4.1.3.4) activities were detected in isolated latex. HMG-CoA reductase was localized to a membrane-bound fraction of a 5000g pellet of latex. The rate of conversion of HMG-CoA to mevalonate by this enzyme is comparable to the overall rate of acetate incorporation into the triterpenoids suggesting that this enzyme is rate-determiningmore » in the biosynthesis of triterpenoids in E. lathyris latex. HMG-CoA reductase of E. lathyris vegetative tissue was localized to the membrane-bound portion of a particulate fraction (18,000g), and was solubilized by treatment with 2% polyoxyethylene ether W-1. Differences in the optimal pH for activity of HMG-CoA reductase from the latex and vegetative tissue suggest that isozymes of the enzyme may be present in the two tissue types. Studies of the incorporation of various precursors into leaf discs and cuttings taken from Copaifera spp. show differences in the rate of incorporation into Copaifera sesquiterpenes suggesting that the site of sesquiterpene biosynthesis may differ in its accessibility to the different substrates and/or reflecting the metabolic controls on carbon allocation to the terpenes. Mevalonate incorporation by Copaifera langsdorfii cuttings into sesquiterpenes was a hundred-fold greater than either acetate or glucose incorporation, however, its incorporation into squalene and triterpenoids was also a hundred-fold greater than the incorporation into sesquiterpenes. 119 refs., 58 figs., 16 tabs.« less
Growth of wormlike micelles in nonionic surfactant solutions: Quantitative theory vs. experiment.
Danov, Krassimir D; Kralchevsky, Peter A; Stoyanov, Simeon D; Cook, Joanne L; Stott, Ian P; Pelan, Eddie G
2018-06-01
Despite the considerable advances of molecular-thermodynamic theory of micelle growth, agreement between theory and experiment has been achieved only in isolated cases. A general theory that can provide self-consistent quantitative description of the growth of wormlike micelles in mixed surfactant solutions, including the experimentally observed high peaks in viscosity and aggregation number, is still missing. As a step toward the creation of such theory, here we consider the simplest system - nonionic wormlike surfactant micelles from polyoxyethylene alkyl ethers, C i E j . Our goal is to construct a molecular-thermodynamic model that is in agreement with the available experimental data. For this goal, we systematized data for the micelle mean mass aggregation number, from which the micelle growth parameter was determined at various temperatures. None of the available models can give a quantitative description of these data. We constructed a new model, which is based on theoretical expressions for the interfacial-tension, headgroup-steric and chain-conformation components of micelle free energy, along with appropriate expressions for the parameters of the model, including their temperature and curvature dependencies. Special attention was paid to the surfactant chain-conformation free energy, for which a new more general formula was derived. As a result, relatively simple theoretical expressions are obtained. All parameters that enter these expressions are known, which facilitates the theoretical modeling of micelle growth for various nonionic surfactants in excellent agreement with the experiment. The constructed model can serve as a basis that can be further upgraded to obtain quantitative description of micelle growth in more complicated systems, including binary and ternary mixtures of nonionic, ionic and zwitterionic surfactants, which determines the viscosity and stability of various formulations in personal-care and house-hold detergency. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.
Sandoval, Catalina; Ortega, Anakenna; Sanchez, Susana A.; Morales, Javier; Gunther, German
2015-01-01
Background Reactors found in nature can be described as micro-heterogeneous systems, where media involved in each micro-environment can behave in a markedly different way compared with the properties of the bulk solution. The presence of water molecules in micro-organized assemblies is of paramount importance for many chemical processes, ranging from biology to environmental science. Self-organized molecular assembled systems are frequently used to study dynamics of water molecules because are the simplest models mimicking biological membranes. The hydrogen bonds between sucrose and water molecules are described to be stronger (or more extensive) than the ones between water molecules themselves. In this work, we studied the capability of sucrose moiety, attached to alkyl chains of different length, as a surface blocking agent at the water-interface and we compared its properties with those of polyethylenglycol, a well-known agent used for this purposes. Published studies in this topic mainly refer to the micellization process and the stability of mixed surfactant systems using glycosides. We are interested in the effect induced by the presence of sucrose monoesters at the interface (direct and reverse micelles) and at the palisade (mixtures with Triton X-100). We believe that the different functional group (ester), the position of alkyl chain (6-O) and the huge capability of sucrose to interact with water will dramatically change the water structuration at the interface and at the palisade, generating new possibilities for technological applications of these systems. Results Our time resolved and steady state fluorescence experiments in pure SEs micelles show that sucrose moieties are able to interact with a high number of water molecules promoting water structuration and increased viscosity. These results also indicate that the barrier formed by sucrose moieties on the surface of pure micelles is more effective than the polyoxyethylene palisade of Triton X-100. The fluorescence quenching experiments of SEs at the palisade of Triton X-100 micelles indicate a blocking effect dependent on the number of methylene units present in the hydrophobic tail of the surfactant. A remarkable blocking effect is observed when there is a match in size between the hydrophobic regions forming the apolar core (lauryl SE/ Triton X-100). This blocking effect disappears when a mismatch in size between hydrophobic tails, exists due to the disturbing effect on the micelle core. PMID:25905632
21 CFR 178.3130 - Antistatic and/or anti-fogging agents in food-packaging materials.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Antistatic and/or anti-fogging agents in food..., fresh fruits, and fresh vegetables. Alpha-(Carboxymethyl)-omega-(tetradecyloxy)polyoxyethylene) For use... at levels not to exceed 3.0 percent by weight of polystyrene or rubber-modified polystyrene complying...
21 CFR 178.3130 - Antistatic and/or anti-fogging agents in food-packaging materials.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Antistatic and/or anti-fogging agents in food..., fresh fruits, and fresh vegetables. Alpha-(Carboxymethyl)-omega-(tetradecyloxy)polyoxyethylene) For use... at levels not to exceed 3.0 percent by weight of polystyrene or rubber-modified polystyrene complying...
A Simple, Inexpensive Molecular Weight Measurement for Water-Soluble Polymers Using Microemulsions.
ERIC Educational Resources Information Center
Mathias, Lon J.; Moore, D. Roger
1985-01-01
Describes an experiment involving use of a microemulsion and its characteristic thermal phase change to determine molecular weights of polyoxyethylene samples. The experiment provides students with background information on polymers and organized media and with experience in evaluating polymer molecular weight by using a unique property of a…
40 CFR 180.960 - Polymers; exemptions from the requirement of a tolerance.
Code of Federal Regulations, 2013 CFR
2013-07-01
...-hydroxypoly (oxypropylene) and/or poly (oxyethylene) polymers where the alkyl chain contains a minimum of six... (oxypropylene) poly(oxyethylene) block copolymer; the minimum poly(oxypropylene) content is 27 moles and the... number average molecular weight (in amu), 900,000 62386-95-2 Monophosphate ester of the block copolymer α...
Tush, Daniel; Loftin, Keith A.; Meyer, Michael T.
2013-01-01
Little is known about the occurrence, fate, and effects of the ancillary additives in pesticide formulations. Polyoxyethylene tallow amine (POEA) is a non-ionic surfactant used in many glyphosate formulations, a widely applied herbicide both in agricultural and urban environments. POEA has not been previously well characterized, but has been shown to be toxic to various aquatic organisms. Characterization of technical mixtures using ultra-high performance liquid chromatography (UHPLC) and mass spectrometry shows POEA is a complex combination of homologs of different aliphatic moieties and ranges of ethoxylate units. Tandem mass spectrometry experiments indicate that POEA homologs generate no product ions readily suitable for quantitative analysis due to poor sensitivity. A comparison of multiple high performance liquid chromatography (HPLC) and UHPLC analytical columns indicates that the stationary phase is more important in column selection than other parameters for the separation of POEA. Analysis of several agricultural and household glyphosate formulations confirms that POEA is a common ingredient but ethoxylate distributions among formulations vary.
NASA Astrophysics Data System (ADS)
Taniguchi, Ikuo; Wada, Norihisa; Kinugasa, Kae; Higa, Mitsuru
2017-11-01
Due to CO2-philic nature of polyoxyethylene (POE), a dense POE comb structure was tethered onto PMMA backbone to develop CO2 separation membranes over N2. The resulting hyper-branched polymers displayed preferential CO2 permeation. When the polymer thin layer was formed on a high gas permeable polydimethylsiloxane (PDMS) support by a spray-coating manner, the resulting thin film composite (TFC) membranes displayed very high CO2 permeability. However, the CO2 selectivity, which was the permeability ratio of CO2 over N2, was moderate and lower than 50. To enhance the selectivity, poly(amidoamine) (PAMAM) was introduced to the hyper-branched polymers in the CO2-selective layer of the TFC membranes. The CO2 selectivity increased from 47 to 90 with increasing PAMAM content to 40 wt%, and it was drastically enhanced to 350 with PAMAM content of 50 wt%. Differential scanning calorimetry (DSC) and laser microscope revealed formation of PAMAM-rich domain at the higher amine content, where CO2 could readily migrate in comparison to the other polymeric fractions.
NASA Astrophysics Data System (ADS)
Hashimoto, Shuichi; Thomas, J. Kerry
1984-08-01
The effect of caffeine on a few photo-induced reactions of pyrene in micellar sodium lauryl sulfate (NaLS) has been studied. In these systems caffeine complexes with the pyrene (K asso = 85 ± 10 M -1 and also with the other reactants, e.g. Cu 2+ or TI +. The efficiencies of reactions which involve contact, i.e. pyrene excimer formation, and quenching by TI + ions to give the triplet state of pyrene, are significantly reduced in the presence of caffeine, due to geometric inhibitions formed by the complexation processes. The kinetics of photo-induced electron transfer, e.g. between excited pyrene and Cu 2+, are not affected. However, the subsequent reactions of the products are modified and the yield of ionic products is markedly increased.
Jungersted, Jakob Mutanu; Høgh, Julie K; Hellegren, Lars I; Jemec, Gregor B E; Agner, Tove
2011-05-01
The skin barrier, located in the stratum corneum, is influenced mainly by the lipid and protein composition of this layer. In eczematous diseases impairment of the skin barrier is thought to be of prime importance. Topical anti-inflammatory drugs and emollients are the most widely used eczema treatments. The aim of this study was to examine the effects of topically applied corticosteroid, tacrolimus and emollient on stratum corneum lipids and barrier parameters. Nineteen healthy volunteers participated in the study. Both forearms of the subjects were divided into four areas, which were treated twice daily for one week with betamethasone, tacrolimus, emollient, or left untreated, respectively. After one week each area was challenged with a 24 h sodium lauryl sulphate patch test. The lipids were collected using the cyanoacrylate method and evaluated by high performance thin layer chromatography. For evaluation of the skin barrier, transepidermal water loss, erythema and electrical capacitance were measured. The ceramide/cholesterol ratio was increased in betamethasone- (p = 0.008) and tacrolimus-treated (p = 0.025) skin compared with emollient-treated skin. No differences in ceramide subgroups were found between treatment regimes. Pretreatment with betamethasone (p = 0.01) or with tacrolimus (p = 0.001) causes a decreased inflammatory response to sodium lauryl sulphate compared with emollient. In conclusion, treatment with betamethasone and tacrolimus has a positive effect on the ceramide/cholesterol ratio and susceptibility to irritant reaction compared with an emollient.
The in vitro impact of toothpaste extracts on cell viability.
Cvikl, Barbara; Lussi, Adrian; Gruber, Reinhard
2015-06-01
Toothpastes contain three main components: detergents, abrasives, and fluoride. Detergents, particularly sodium lauryl sulfate, have been proposed as components that enable toothpastes to produce cytotoxic effects in vitro. However, not all toothpastes contain sodium lauryl sulfate, and almost no studies have found an association between detergents and the in vitro cytotoxicity of toothpastes. The present study examined the in vitro cytotoxicity of nine commercially available toothpastes containing four different detergents. Toothpastes were diluted in serum-free medium, centrifuged, and filter sterilized. The half-lethal concentration of the toothpaste-conditioned medium (TCM) was calculated based on the formation of formazan by gingival fibroblasts, oral squamous cell carcinoma HSC-2 cells, and L929 cells. Cell proliferation was analyzed, and live-dead staining was performed, after exposure of cells to conditioned medium prepared with 1% toothpaste (1% TCM). It was found that toothpastes containing sodium lauryl sulfate and amine fluoride strongly inhibited cell viability with the half-lethal concentration being obtained with conditioned medium prepared with approximately 1% toothpaste (1% TCM). Toothpastes containing cocamidopropyl betaine and Steareth-20 showed higher half-lethal concentration values, with the half-lethal concentration being obtained with conditioned medium prepared with 10% (10% TCM) and 70% (70% TCM) toothpaste, respectively. Proliferation and live-dead data were consistent with the cell-viability analyses. These results demonstrate that the type of detergent in toothpastes can be associated with changes in in vitro cell toxicity. © 2015 Eur J Oral Sci.
Alonso, Hernan; Roujeinikova, Anna
2012-11-01
The alkane hydroxylase system of Pseudomonas putida GPo1 allows it to use alkanes as the sole source of carbon and energy. Bacterial alkane hydroxylases have tremendous potential as biocatalysts for the stereo- and regioselective transformation of a wide range of chemically inert unreactive alkanes into valuable reactive chemical precursors. We have produced and characterized the first 2-dimensional crystals of the integral membrane component of the P. putida alkane hydroxylase system, the nonheme di-iron alkane monooxygenase AlkB. Our analysis reveals for the first time that AlkB reconstituted into a lipid bilayer forms trimers. Addition of detergents that do not disrupt the AlkB oligomeric state (decyl maltose neopentyl glycol [DMNG], lauryl maltose neopentyl glycol [LMNG], and octaethylene glycol monododecyl ether [C(12)E(8)]) preserved its activity at a level close to that of the detergent-free control sample. In contrast, the monomeric form of AlkB produced by purification in n-decyl-β-D-maltopyranoside (DM), n-dodecyl-β-D-maltopyranoside (DDM), octyl glucose neopentyl glycol (OGNG), and n-dodecyl-N,N-dimethylamine-N-oxide (LDAO) was largely inactive. This is the first indication that the physiologically active form of membrane-embedded AlkB may be a multimer. We present for the first time experimental evidence that 1-octyne acts as a mechanism-based inhibitor of AlkB. Therefore, despite the lack of any significant full-length sequence similarity with members of other monooxygenase classes that catalyze the terminal oxidation of alkanes, AlkB is likely to share a similar catalytic mechanism.
Rheological characterization of hair shampoo in the presence of dead sea salt.
Abu-Jdayil, B; Mohameed, H A; Sa'id, M; Snobar, T
2004-02-01
In Jordan, a growing industry has been established to produce different types of Dead Sea (DS) cosmetics that have DS salt (contains mainly NaCl, KCl, and MgCl(2)) in their formulas. In this work, the effect of DS salt on the rheology of hair shampoo containing the sodium lauryl ether sulfate as a main active matter was studied. The effects of DS salt and active matter concentration, and the temperature and time of salt mixing, on the rheological properties of hair shampoo were investigated. The salt-free shampoo showed a Newtonian behavior at 'low active matter' (LAM) and shear thinning at 'high active matter' (HAM). The presence of DS salt changed the rheological behavior of LAM shampoo from Newtonian (for the salt-free shampoo) to shear thinning. On the other hand, the behavior of HAM shampoo switched from shear thinning to Newtonian behavior in the presence of high concentration of DS salt. The addition of DS salt increased the apparent viscosity of shampoo to reach a maximum value that corresponded to a salt concentration of 1.5 wt.%. Further addition of DS salt led to a decrease in the shampoo viscosity to reach a value less than that of the salt-free sample at high salt concentration. Changing the mixing temperature (25-45 degrees C) and mixing time (15-120 min) of DS salt with shampoo has no significant influence on the rheological behavior. However, the mixing process increased the apparent viscosity of salt-free shampoo. The power law model fitted well the flow curves of hair shampoo with and without DS salt.
21 CFR 172.822 - Sodium lauryl sulfate.
Code of Federal Regulations, 2010 CFR
2010-04-01
... melting fractions of crude vegetable oils and animal fats, provided that the partition step is followed by... and oils. (c) To insure the safe use of the additive, the label of the food additive container shall...
Characterization of Materials by Raman Scattering
NASA Astrophysics Data System (ADS)
Kozielski, M.
2007-03-01
The paper reports on the use of phonon spectra obtained with the Raman spectroscopy for characterization of different materials. The Raman scattering spectra obtained for zinc selenide crystals, mixed crystals zinc selenide admixtured with magnesium or beryllium, oxide crystals including strontium lanthanum gallate, molecular crystals of triammonium hydrogen diseleniate and a homologous series of polyoxyethylene glycols are analysed.
USDA-ARS?s Scientific Manuscript database
This study was conducted to evaluate the effect of biosurfactants on the populations of Escherichia coli O157:H7 in suspension and on spinach leaves. Eight surfactants including four soybean oil-based biosurfactants, sodium dodecyl sulfate (SDS), polyoxyethylene sorbitan monooleate (Tween 80), sopho...
21 CFR 172.822 - Sodium lauryl sulfate.
Code of Federal Regulations, 2011 CFR
2011-04-01
... high and low melting fractions of crude vegetable oils and animal fats, provided that the partition... deodorization of the fats and oils. (c) To insure the safe use of the additive, the label of the food additive...
Wang, Jing; Jia, Rui; Wang, Jiaxi; Sun, Zhiqiang; Wu, Zitao; Liu, Rutao; Zong, Wansong
2018-02-01
As a classic type of anionic surfactants, sodium lauryl sulfonate (SLS) might change the structure and function of antioxidant enzyme catalase (CAT) through their direct interactions. However, the underlying molecular mechanism is still unknown. This study investigated the direct interaction of SLS with CAT molecule and the underlying mechanisms using multi-spectroscopic methods, isothermal titration calorimetry, and molecular docking studies. No obvious effects were observed on CAT structure and activity under low SLS concentration exposure. The particle size of CAT molecule decreased and CAT activity was slightly inhibited under high SLS concentration exposure. SLS prefers to bind to the interface of CAT mainly via van der Waals' forces and hydrogen bonds. Subsequently, SLS interacts with the amino acid residues around the heme groups of CAT via hydrophobic interactions and might inhibit CAT activity. © 2017 Wiley Periodicals, Inc.
Brown, Ronald S; Smith, Langston; Glascoe, Alison L
2018-02-01
Sodium lauryl sulfate (SLS), a popular surface active agent ingredient within toothpastes, is known for its foaming action. Surface active agents increase the effectiveness of toothpastes with respect to dental plaque removal. SLS is a known irritant and also has allergenic potential. The authors report 3 patients with oral pain secondary to inflammation of the dorsal anterior tongue. These patients were all using toothpastes with SLS as an ingredient. The dorsal tongue lesions and oral pain resolved upon switching to toothpastes without SLS as an ingredient. Clinicians should be aware of the potential of SLS within toothpastes to cause oral mucosal inflammatory reactions of the anterior dorsal tongue. To our knowledge, these are the first case reports of oral mucosal inflammatory reactions of the anterior dorsal tongue associated with SLS containing toothpastes. Copyright © 2017 Elsevier Inc. All rights reserved.
Glycerin Borax Treatment of Exfoliative Cheilitis Induced by Sodium Lauryl Sulfate: a Case Report
2016-01-01
This paper reports on the results of a case study of a 19-year-old female who presented to the Oral Medicine clinic with a chief complaint of scaly and peeling lips. The lesions had persisted on her lips for more than 7 years and were refractory to previous treatment. Her physician’s diagnosis was contact dermatitis. We diagnosed this patient as having exfoliative cheilitis (EC). A patch test using the toothpaste containing sodium lauryl sulfate (SLS) was positive and the patient discontinued using it. Instead, she started using a toothpaste not containing SLS. One year after treating her lesions with hydrogen peroxide mouthwash 1% and glycerin borax, a gradual improvement was observed until returning to normal. Glycerin borax was safe, low cost and simple to use in treatment of refractory exfoliative cheilitis. SLS may have been a precipitating factor in EC in this case. PMID:27789914
Glycerin Borax Treatment of Exfoliative Cheilitis Induced by Sodium Lauryl Sulfate: a Case Report.
Thongprasom, Kobkan
2016-06-01
This paper reports on the results of a case study of a 19-year-old female who presented to the Oral Medicine clinic with a chief complaint of scaly and peeling lips. The lesions had persisted on her lips for more than 7 years and were refractory to previous treatment. Her physician's diagnosis was contact dermatitis. We diagnosed this patient as having exfoliative cheilitis (EC). A patch test using the toothpaste containing sodium lauryl sulfate (SLS) was positive and the patient discontinued using it. Instead, she started using a toothpaste not containing SLS. One year after treating her lesions with hydrogen peroxide mouthwash 1% and glycerin borax, a gradual improvement was observed until returning to normal. Glycerin borax was safe, low cost and simple to use in treatment of refractory exfoliative cheilitis. SLS may have been a precipitating factor in EC in this case.
Dewetting-Induced Photoluminescent Enhancement of Poly(lauryl methacrylate)/Quantum Dot Thin Films.
Geldmeier, Jeffrey; Rile, Lexy; Yoon, Young Jun; Jung, Jaehan; Lin, Zhiqun; Tsukruk, Vladimir V
2017-12-19
A new method for enhancing photoluminescence from quantum dot (QD)/polymer nanocomposite films is proposed. Poly(lauryl methacrylate) (PLMA) thin films containing embedded QDs are intentionally allowed to undergo dewetting on substrates by exposure to a nonsolvent vapor. After controlled dewetting, films exhibited typical dewetting morphologies with increased amounts of scattering that served to outcouple photoluminescence from the film and reduce internal light propagation within the film. Up to a 5-fold enhancement of the film emission was achieved depending on material factors such as the initial film thickness and QD concentration within the film. An increase in initial film thickness was shown to increase the dewetted maximum feature size and its characteristic length until a critical thickness was reached where dewetting became inhibited. A unique light exposure-based photopatterning method is also presented for the creation of high contrast emissive patterns as guided by spatially controlled dewetting.
Removal of sodium lauryl sulphate by coagulation/flocculation with Moringa oleifera seed extract.
Beltrán-Heredia, J; Sánchez-Martín, J
2009-05-30
Among other natural flocculant/coagulant agents, Moringa oleifera seed extract ability to remove an anionic surfactant has been evaluated and it has been found to be very interesting. Sodium lauryl sulphate was removed from aqueous solutions up to 80% through coagulation/flocculation process. pH and temperature were found to be not very important factors in removal efficiency. Freundlich (F), Frumkin-Fowler-Guggenheim (FFG) and Gu-Zhu (GZ) models were used to adjust experimental data in a solid-liquid adsorption hypothesis. Last one resulted to be the most accurate one. Several data fit parameters were determined, as Freundlich order, which was found to be 1.66, Flory-Huggins interaction parameter from FFG model, which was found to be 4.87; and limiting Moringa surfactant adsorption capacity from GZ model, which was found to be 2.13 x 10(-3)mol/g.
Abdl-Rahman, M A; Sawiress, F A R; Abd El-Aty, A M
2010-01-01
The aim of the current study was to evaluate the effect of sodium lauryl sulfate-fumaric acid coupled addition on in vitro methangenesis and rumen fermentation. Evaluation was carried out using in vitro gas production technique. Ruminal contents were collected from five steers immediately after slaughtering and used for preparation of inoculums of mixed rumen microorganisms. Rumen fluid was then mixed with the basal diet of steers and used to generate four treatments, negative control (no additives), sodium lauryl sulfate (SLS) treated, fumaric acid treated, and SLS-fumaric acid coupled addition treated. The results revealed that, relative to control, efficiency in reduction of methanogenesis was as follows: coupled addition > SLS-addition > fumaric acid addition. Both SLS-addition and SLS-fumaric acid coupled addition demonstrated a decremental effect on ammonia nitrogen (NH(3)-N), total short chain volatile fatty acids (SCVFAs) concentrations and the amount of substrate degraded, and an increment effect on microbial mass and microbial yield (Y(ATP)). Nevertheless, fumaric acid did not alter any of the previously mentioned parameters but induced a decremental effect on NH(3)-N. Furthermore, both fumaric acid and SLS-fumaric acid coupled addition increased propionate at the expense of acetate and butyrate, while, defaunation increased acetate at the expense of propionate and butyrate. The pH value was decreased by all treatments relative to control, while, cellulase activity did not differ by different treatments. The current study can be promising strategies for suppressing ruminal methane emissions and improving ruminants feed efficiency.
Abdl-Rahman, M. A.; Sawiress, F. A. R.; Abd El-Aty, A. M.
2010-01-01
The aim of the current study was to evaluate the effect of sodium lauryl sulfate-fumaric acid coupled addition on in vitro methangenesis and rumen fermentation. Evaluation was carried out using in vitro gas production technique. Ruminal contents were collected from five steers immediately after slaughtering and used for preparation of inoculums of mixed rumen microorganisms. Rumen fluid was then mixed with the basal diet of steers and used to generate four treatments, negative control (no additives), sodium lauryl sulfate (SLS) treated, fumaric acid treated, and SLS-fumaric acid coupled addition treated. The results revealed that, relative to control, efficiency in reduction of methanogenesis was as follows: coupled addition > SLS-addition > fumaric acid addition. Both SLS-addition and SLS-fumaric acid coupled addition demonstrated a decremental effect on ammonia nitrogen (NH3–N), total short chain volatile fatty acids (SCVFAs) concentrations and the amount of substrate degraded, and an increment effect on microbial mass and microbial yield (YATP). Nevertheless, fumaric acid did not alter any of the previously mentioned parameters but induced a decremental effect on NH3–N. Furthermore, both fumaric acid and SLS-fumaric acid coupled addition increased propionate at the expense of acetate and butyrate, while, defaunation increased acetate at the expense of propionate and butyrate. The pH value was decreased by all treatments relative to control, while, cellulase activity did not differ by different treatments. The current study can be promising strategies for suppressing ruminal methane emissions and improving ruminants feed efficiency. PMID:20445794
21 CFR 172.210 - Coatings on fresh citrus fruit.
Code of Federal Regulations, 2010 CFR
2010-04-01
... CONSUMPTION Coatings, Films and Related Substances § 172.210 Coatings on fresh citrus fruit. Coatings may be... a 2:1 ratio. Sodium lauryl sulfate Complying with § 172.822. As a film former. Wood rosin Color of K...
Synthesis of mesoporous nano-hydroxyapatite by using zwitterions surfactant
Mesoporous nano-hydroxyapatite (mn-HAP) was successfully synthesized via a novel micelle-templating method using lauryl dimethylaminoacetic acid as zwitterionic surfactant. The systematic use of such a surfactant in combination with microwave energy inputenables the precise contr...
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...
Lubricating Coolant for Cold Rolling of Aluminum and Its Alloys,
The title fluid consists of a mixtures of alkyl esters of high molecular weight acids, an ester of xylitol and a C(subscript 6) or higher fatty acid...molecular weight acids 3-6, an ester of xylitol and a C(subscript 6) or higher fatty acid 1-3, an Al soap 0.3-1, a mineral oil 10-60, a polyoxyethylene
21 CFR 178.3130 - Antistatic and/or anti-fogging agents in food-packaging materials.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Antistatic and/or anti-fogging agents in food...-(Carboxymethyl)-omega-(tetradecyloxy)polyoxyethylene) For use only as an antistatic and/or antifogging agent at... § 176.170(c) of this chapter. 2. As antistatic agents at levels not to exceed 3.0 percent by weight of...
Qi, Sheng; Belton, Peter; McAuley, William; Codoni, Doroty; Darji, Neerav
2013-04-01
Gelucire 50/13, a polyoxyethylene glycol glyceride mixture, has been widely used in drug delivery, but its moisture uptake behaviour is still poorly understood. In this study, the effects of relative humidity, temperature, and drug incorporation on the moisture uptake of Gelucire are reported in relation to their practical implications for preparation of solid dispersions using this material. DVS combined with kinetics modelling was used as the main experimental method to study the moisture uptake behaviour of Gelucire. Thermal and microscopic methods were employed to investigate the effect of moisture uptake on the physical properties of the material and drug loaded solid dispersions. The moisture uptake by Gelucire 50/13 is temperature and relative humidity dependent. At low temperatures and low relative humidities, moisture sorption follows a GAB model. The model fitting indicated that at high relative humidities the sorption is a complex process, potentially involving PEG being dissolved and the PEG solution acting as solvent to dissolve other components. Careful control of the storage and processing environmental conditions are required when using Gelucire 50/13. The incorporation of model drugs not only influences the moisture uptake capacity of Gelucire 50/13 but also the solidification behaviour.
Uyama, Makoto; Araki, Hidefumi; Fukuhara, Tadao; Watanabe, Kei
2018-06-07
The α-form hydrated crystalline phase (often called as an α-gel) is one of the hydrated crystalline phases which can be exhibited by surfactants and lipids. In this study, a novel system of an α-form hydrated crystal was developed, composed of 3-(10-carboxydecyl)-1,1,1,3,5,5,5-heptamethyl trisiloxane (CDTS), polyoxyethylene (5 mol) glyceryl monostearate (GMS-5), higher alcohol. This is the first report to indicate that a silicone surfactant can form an α-form hydrated crystal. The physicochemical properties of this system were characterized by small and wide angle X-ray scattering (SWAXS), differential scanning calorimetry (DSC), and diffusion-ordered NMR spectroscopy (DOSY) experiments. SWAXS and DSC measurements revealed that a plurality of crystalline phases coexist in the CDTS/higher alcohol/water ternary system. By adding GMS-5 to the ternary system, however, a wide region of a single α-form hydrated crystalline phase was obtained. The self-diffusion coefficients (D sel ) from the NMR measurements suggested that all of the CDTS, GMS-5, and higher alcohol molecules were incorporated into the same α-form hydrated crystals.
Hofmann, Michael A.
2006-11-14
The present invention is directed to sulfonimide-containing polymers, specifically sulfonimide-containing poly(arylene ether)s and sulfonimide-containing poly(arylene ether sulfone)s, and processes for making the sulfonimide-containing poly(arylene ether)s and sulfonimide-containing poly(arylene ether sulfone)s, for use conductive membranes and fuel cells.
Greco, Kristyn; Bogner, Robin
2011-09-01
Forming a salt is a common way to increase the solubility of a poorly soluble compound. However, the solubility enhancement gained by salt formation may be lost due to solution-mediated phase transformation (SMPT) during dissolution. The SMPT of a salt can occur due to a supersaturated solution near the dissolving surface caused by pH or other solution conditions. In addition to changes in pH, surfactants are also known to affect SMPT. In this study, SMPT of a highly soluble salt, haloperidol mesylate, at pH 7 in the presence of a commonly used surfactant, sodium lauryl sulfate (SLS), was investigated. Dissolution experiments were performed using a flow-through dissolution apparatus with solutions containing various concentrations of SLS. Compacts of haloperidol mesylate were observed during dissolution in the flow-through apparatus using a stereomicroscope. Raman microscopy was used to characterize solids. The dissolution of haloperidol mesylate was significantly influenced by the addition of sodium lauryl sulfate. In conditions where SMPT was expected, the addition of SLS at low concentrations (0.1-0.2 mM) reduced the dissolution of haloperidol mesylate. In solutions containing concentrations of SLS above the critical micelle concentration (CMC) (10-15 mM), the dissolution of haloperidol mesylate increased compared to below the CMC. The solids recovered from solubility experiments of haloperidol mesylate indicated that haloperidol free base precipitated at all concentrations of SLS. Above 5 mM of SLS, Raman microscopy suggested a new form, perhaps the estolate salt. The addition of surfactant in solids that undergo solution-mediated phase transformation can add complexity to the dissolution profiles and conversion.
Novel Nanocomposites of Poly(lauryl methacrylate)-Grafted Al2O3 Nanoparticles in LDPE.
Cobo Sánchez, Carmen; Wåhlander, Martin; Taylor, Nathaniel; Fogelström, Linda; Malmström, Eva
2015-11-25
Aluminum oxide nanoparticles (NPs) were surface-modified by poly(lauryl methacrylate) (PLMA) using surface-initiated atom-transfer radical polymerization (SI-ATRP) of lauryl methacrylate. Nanocomposites were obtained by mixing the grafted NPs in a low-density polyethylene (LDPE) matrix in different ratios. First, the NPs were silanized with different aminosilanes, (3-aminopropyl)triethoxysilane, and 3-aminopropyl(diethoxy)methylsilane (APDMS). Subsequently, α-BiB, an initiator for SI-ATRP, was attached to the amino groups, showing higher immobilization ratios for APDMS and confirming that fewer self-condensation reactions between silanes took place. In a third step SI-ATRP of LMA at different times was performed to render PLMA-grafted NPs (NP-PLMAs), showing good control of the polymerization. Reactions were conducted for 20 to 60 min, obtaining a range of molecular weights between 23 000 and 83 000 g/mol, as confirmed by size-exclusion chromoatography of the cleaved grafts. Nanocomposites of NP-PLMAs at low loadings in LDPE were prepared by extrusion. At low loadings, 0.5 wt % of inorganic content, the second yield point, storage, and loss moduli increased significantly, suggesting an improved interphase as an effect of the PLMA grafts. These observations were also confirmed by an increase in transparency of the nanocomposite films. At higher loadings, 1 wt % of inorganics, the increasing amount of PLMA gave rise to the formation of small aggregates, which may explain the loss of mechanical properties. Finally, dielectric measurements were performed, showing a decrease in tan δ values for LDPE-NP-PLMAs, as compared to the nanocomposites containing unmodified NP, thus indicating an improved interphase between the NPs and LDPE.
Peruzzo, Daiane Cristina; Salvador, Sérgio Luis; Sallum, Antonio Wilson; da Nogueira-Filho, Getúlio Rocha
2008-10-01
The purpose of the present investigation was to evaluate the effects of sodium lauryl sulphate (SLS), present in a commercial dentifrice, on the formation of volatile sulphur compounds (VSC) and tongue coating in a panel of periodontally healthy subjects. A two-step blinded, crossover, randomized study was carried out in 25 dental students with healthy periodontium; these were divided into two experimental groups: SLS (dentifrice with SLS) and WSLS (dentifrice without SLS). The volunteers received the designated dentifrice and a new toothbrush for a 3x/day brushing regimen for 2 periods of 30 days. A seven-day washout interval was used between the periods. The assessed parameters were: plaque index (PI), gingival index (GI), organoleptic breath (ORG), VSC levels by portable sulphide monitor before (H1) and after (H2) cleaning of the tongue, tongue coating wet weight (TC) and benzoyl-DL-arginine-naphthylamide (BANA) test from tongue coating samples. The intra-group analysis showed a decrease in the median of organoleptic scores from 3 to 2 after 30 days for the SLS group (p < 0.05). The inter-group analysis showed lower values in ORG and H1 for the SLS group (p < 0.05). There was no difference between the amount of TC in SLS and WSLS groups. In the BANA test, the presence of SLS did not affect the BANA number of +/- results (p > 0.05). These findings suggest that sodium lauryl sulphate (SLS), present in dentifrice, appears to prevent VSC formation in morning bad breath regardless of the amount of tongue coating in periodontally healthy subjects.
Taghizadeh, S Mojtaba; Moghimi-Ardakani, Ali; Mohamadnia, Fatemeh
2015-03-01
A series of drug-in-adhesive transdermal drug delivery systems (patch) with different chemical penetration enhancers were designed to deliver drug through the skin as a site of application. The objective of our effort was to study the influence of various chemical penetration enhancers on skin permeation rate and adhesion properties of a transdermal drug delivery system using Box-Behnken experimental design. The response surface methodology based on a three-level, three-variable Box-Behnken design was used to evaluate the interactive effects on dependent variables including, the rate of skin permeation and adhesion properties, namely peel strength and tack value. Levulinic acid, lauryl alcohol, and Tween 80 were used as penetration enhancers (patch formulations, containing 0-8% of each chemical penetration enhancer). Buprenorphine was used as a model penetrant drug. The results showed that incorporation of 20% chemical penetration enhancer into the mixture led to maximum skin permeation flux of buprenorphine from abdominal rat skin while the adhesion properties decreased. Also that skin flux in presence of levulinic acid (1.594 μg/cm(2) h) was higher than Tween 80 (1.473 μg/cm(2) h) and lauryl alcohol (0.843 μg/cm(2) h), and in mixing these enhancers together, an additional effect was observed. Moreover, it was found that each enhancer increased the tack value, while levulinic acid and lauryl alcohol improved the peel strength but Tween 80 reduced it. These findings indicated that the best chemical skin penetration enhancer for buprenorphine patch was levulinic acid. Among the designed formulations, the one which contained 12% (wt/wt) enhancers exhibited the highest efficiency.
Alonso, Hernan
2012-01-01
The alkane hydroxylase system of Pseudomonas putida GPo1 allows it to use alkanes as the sole source of carbon and energy. Bacterial alkane hydroxylases have tremendous potential as biocatalysts for the stereo- and regioselective transformation of a wide range of chemically inert unreactive alkanes into valuable reactive chemical precursors. We have produced and characterized the first 2-dimensional crystals of the integral membrane component of the P. putida alkane hydroxylase system, the nonheme di-iron alkane monooxygenase AlkB. Our analysis reveals for the first time that AlkB reconstituted into a lipid bilayer forms trimers. Addition of detergents that do not disrupt the AlkB oligomeric state (decyl maltose neopentyl glycol [DMNG], lauryl maltose neopentyl glycol [LMNG], and octaethylene glycol monododecyl ether [C12E8]) preserved its activity at a level close to that of the detergent-free control sample. In contrast, the monomeric form of AlkB produced by purification in n-decyl-β-d-maltopyranoside (DM), n-dodecyl-β-d-maltopyranoside (DDM), octyl glucose neopentyl glycol (OGNG), and n-dodecyl-N,N-dimethylamine-N-oxide (LDAO) was largely inactive. This is the first indication that the physiologically active form of membrane-embedded AlkB may be a multimer. We present for the first time experimental evidence that 1-octyne acts as a mechanism-based inhibitor of AlkB. Therefore, despite the lack of any significant full-length sequence similarity with members of other monooxygenase classes that catalyze the terminal oxidation of alkanes, AlkB is likely to share a similar catalytic mechanism. PMID:22941083
Saat, Gülbahar; Balci, Fadime Mert; Alsaç, Elif Pınar; Karadas, Ferdi; Dag, Ömer
2018-01-01
Mesoporous thin films of transition metal lithiates (TML) belong to an important group of materials for the advancement of electrochemical systems. This study demonstrates a simple one pot method to synthesize the first examples of mesoporous LiCoO 2 and LiMn 2 O 4 thin films. Molten salt assisted self-assembly can be used to establish an easy route to produce mesoporous TML thin films. The salts (LiNO 3 and [Co(H 2 O) 6 ](NO 3 ) 2 or [Mn(H 2 O) 4 ](NO 3 ) 2 ) and two surfactants (10-lauryl ether and cethyltrimethylammonium bromide (CTAB) or cethyltrimethylammonium nitrate (CTAN)) form stable liquid crystalline mesophases. The charged surfactant is needed for the assembly of the necessary amount of salt in the hydrophilic domains of the mesophase, which produces stable metal lithiate pore-walls upon calcination. The films have a large pore size with a high surface area that can be increased up to 82 m 2 g -1 . The method described can be adopted to synthesize other metal oxides and metal lithiates. The mesoporous thin films of LiCoO 2 show promising performance as water oxidation catalysts under pH 7 and 14 conditions. The electrodes, prepared using CTAN as the cosurfactant, display the lowest overpotentials in the literature among other LiCoO 2 systems, as low as 376 mV at 10 mA cm -2 and 282 mV at 1 mA cm -2 . © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Srirattana, Supawan; Piaowan, Kitsanateen; Lowry, Gregory V; Phenrat, Tanapon
2017-09-01
Nanoscale zerovalent iron (NZVI) is a promising remediation agent for volatile organic compound (VOC) contamination in saturated sub-surfaces, but is rarely applied to the vadose zone as there are not enough water molecules in the unsaturated zone to participate in reductive dechlorination. In this study, we evaluated the possibility of using foam as a carrying vehicle to emplace NZVI in unsaturated porous media followed by the application of low frequency-electromagnetic field (LF-EMF) to enhance VOC volatilization in laboratory batch reactors. We found that the optimal condition for generating foam-based NZVI (F-NZVI) was using sodium lauryl ether sulfate (SLES) at a concentration of 3% (w/w) and a N 2 flow rate of 500 mL/min. Also, F-NZVI could carry as much as 41.31 g/L of NZVI in the liquid phase of the foam and generate heat to raise ΔT to 77 °C in 15 min under an applied LF-EMF (150 kHz and 13 A). Under these conditions, F-NZVI together with LF-EMF enhanced trichloroethylene (TCE) volatilization from TCE-dense non-aqueous phase liquid (DNAPL) in unsaturated sand by 39.51 ± 6.59-fold compared to reactors without LF-EMF application. This suggested that using F-NZVI together with LF-EMF could theoretically be an alternative to radio frequency heating (RFH) as it requires a much lower irradiation frequency (336-fold lower), which should result in significantly lower capital and operational costs compared to RFH. Copyright © 2017 Elsevier Ltd. All rights reserved.
Code of Federal Regulations, 2011 CFR
2011-07-01
... program. Requirements as specified in § 721.72 (a), (b), (c), (d), (f), (g)(3)(ii), and (g)(5). (ii) Release to water. Requirements as specified in § 721.90 (a)(4), (b)(4) and (c)(4) (where N = 400 ppb). (b... oxide adduct (PMN P-90-360) is subject to reporting under this section for the significant new uses...
Bondi, Cara Am; Marks, Julia L; Wroblewski, Lauren B; Raatikainen, Heidi S; Lenox, Shannon R; Gebhardt, Kay E
2015-01-01
Environmental chemical exposure is a major concern for consumers of packaged goods. The complexity of chemical nomenclature and wide availability of scientific research provide detailed information but lends itself to misinterpretation by the lay person. For the surfactant sodium lauryl sulfate (SLS), this has resulted in a misunderstanding of the environmental health impact of the chemical and statements in the media that are not scientifically supported. This review demonstrates how scientific works can be misinterpreted and used in a manner that was not intended by the authors, while simultaneously providing insight into the true environmental health impact of SLS. SLS is an anionic surfactant commonly used in consumer household cleaning products. For decades, this chemical has been developing a negative reputation with consumers because of inaccurate interpretations of the scientific literature and confusion between SLS and chemicals with similar names. Here, we review the human and environmental toxicity profiles of SLS and demonstrate that it is safe for use in consumer household cleaning products.
NASA Astrophysics Data System (ADS)
Arneli; Safitri, Z. F.; Pangestika, A. W.; Fauziah, F.; Wahyuningrum, V. N.; Astuti, Y.
2017-02-01
This research aims to study the influence of activating agents to produce rice husk based-carbon with high adsorption capacity and efficiency for either hazardous organic molecules or heavy metals which are unfriendly for the environment. Firstly, rice husk was burned by pyrolysis at different temperatures to produce rice husk-based carbon. To improve its ability as an adsorbent, carbon was treated with activating agents, namely, H3PO4 and KOH at room and high temperature (420 °C). The performance of carbon was then tested by contacting it with surfactant (SLS). Finally, the surfactant-modified active carbon was applied for chrome metal removal. The result shows that activation of carbon using phosphate acid (H3PO4) was more effective than potassium hydroxide (KOH) conducted at high temperature to adsorb sodium lauryl sulfate (SLS) and chrome metal with the adsorption capacity 1.50 mgg-1 and 0.375 mgg-1, respectively.
Impact of sodium lauryl sulfate in oral liquids on e-tongue measurements.
Immohr, Laura Isabell; Turner, Roy; Pein-Hackelbusch, Miriam
2016-12-30
During development of oral liquid medicines taste assessment is often required to evaluate taste and taste masking. Electronic tongue analysis can provide taste assessment of medicinal products but should only be conducted with medicines that interact with the instrument without damaging the sensor membranes or interfering with their electrical output so that robust data is generated. To explore the impact of a substance deemed unsuitable for electronic tongue analysis the influence of the anionic surfactant sodium lauryl sulfate (SLS), on the performance of the electronic tongue was conducted using electronic tongues equipped with self-developed PVC based sensors. The results showed a significant impact of SLS on all applied sensor types and an alteration of the sensor's sensitivity. Nevertheless, concentration dependent sensor responses could still be obtained and the sensor performance was not impacted negatively. Assessment of unsuitable substances should therefore be evaluated prior to performing electronic tongue analysis so that their impact is understood fully. Copyright © 2016 Elsevier B.V. All rights reserved.
Bondi, Cara AM; Marks, Julia L; Wroblewski, Lauren B; Raatikainen, Heidi S; Lenox, Shannon R; Gebhardt, Kay E
2015-01-01
Environmental chemical exposure is a major concern for consumers of packaged goods. The complexity of chemical nomenclature and wide availability of scientific research provide detailed information but lends itself to misinterpretation by the lay person. For the surfactant sodium lauryl sulfate (SLS), this has resulted in a misunderstanding of the environmental health impact of the chemical and statements in the media that are not scientifically supported. This review demonstrates how scientific works can be misinterpreted and used in a manner that was not intended by the authors, while simultaneously providing insight into the true environmental health impact of SLS. SLS is an anionic surfactant commonly used in consumer household cleaning products. For decades, this chemical has been developing a negative reputation with consumers because of inaccurate interpretations of the scientific literature and confusion between SLS and chemicals with similar names. Here, we review the human and environmental toxicity profiles of SLS and demonstrate that it is safe for use in consumer household cleaning products. PMID:26617461
Schliemann, Sibylle; Schmidt, Christina; Elsner, Peter
2014-01-01
The objective of our study was to investigate the tandem irritation potential of two organic solvents with concurrent exposure to the hydrophilic detergent irritant sodium lauryl sulphate (SLS). A tandem repeated irritation test was performed with two undiluted organic solvents, cumene (C) and octane (O), with either alternating application with SLS 0.5% or twice daily application of each irritant alone in 27 volunteers on the skin of the back. The cumulative irritation induced over 4 days was quantified using visual scoring and non-invasive bioengineering measurements (skin colour reflectance, skin hydration and transepidermal water loss). Repeated application of C/SLS and O/SLS induced more decline of stratum corneum hydration and higher degrees of clinical irritation and erythema compared to each irritant alone. Our results demonstrate a further example of additive harmful skin effects induced by particular skin irritants and indicate that exposure to organic solvents together with detergents may increase the risk of acquiring occupational contact dermatitis. © 2014 S. Karger AG, Basel.
Coating liposomes with collagen (Mr 50,000) increases uptake into liver.
Fonseca, M J; Alsina, M A; Reig, F
1996-03-13
Collagen-coated small unilamellar liposomes were prepared by incubation of two hydrophobic derivatives of collagen (average Mr 50 000) with preformed vesicles. The introduction of hexyl and lauryl residues to the collagen molecule improved by 10-fold the ability of collagen to coat liposomes. In vitro stability of the different coated vesicles prepared, was studied by their ability to retain entrapped carboxyfluorescein as a function of the time. Coated vesicles were clearly more stable in vitro than control liposomes, except for those containing the lauryl derivative in a protein/phospholipid weight ratio higher than 10(-3). Vesicle clearance from circulation as well as tissue distribution were also determined. Pharmacokinetics (determined by both fluorescence and radioactive techniques) were highly dependent on the injected dose, phospholipids used and the content of collagen. Half-lives were maximum for liposomes composed of saturated phospholipids injected at a dose of 2 micromol phospholipid. Besides, blood elimination of collagen-containing vesicles was about 2-fold faster and liver uptake 1.5 to 2-fold higher than control liposomes.
1981-01-01
Gas production by coliform organisms and Escherichia coli from lauryl tryptose lactose broth (LTLB) was compared with that from brilliant green (lactose) bile broth (BGB). These media were compared with lauryl tryptose mannitol broth (LTMB) with and without added tryptophan for both gas and indole production. At 37 degrees C, LTLB and BGB were both satisfactory for gas production, but at 44 degrees C, LTLB gave fewer false-negative results and was thus significantly less inhibitory than BGB. However when LTLB and LTMB were compared as single-tube confirmatory media, LTLB give a high proportion of false-negative reactions in the indole test at 44 degrees C. The substitution of mannitol for lactose and the addition of tryptophan yielded a satisfactory medium for both confirmation of gas production and the demonstration of indole at 44 degrees C. PMID:7031125
Infectious Multiple Drug Resistance in the Enterobacteriaceae
1978-09-01
charge, relative increase in resistance to lysis by sodium lauryl sulfate , EDTA and lysozyme as well as loss of sensitivity to phages Tl and T4. Other more...to find any significant publica- tion dealing with Shigella membrane proteins. Nonetheless by employing the sodium dodecyl sulfate (SDS
Poly(arylene ether)s containing pendent ethynyl groups
NASA Technical Reports Server (NTRS)
Hergenrother, Paul M. (Inventor); Jensen, Brian J. (Inventor)
1996-01-01
Poly(arylene ether)s containing pendent ethynyl and substituted ethynyl groups and poly(arylene ether) copolymers containing pendent ethynyl and substituted ethynyl groups are readily prepared from bisphenols containing ethynyl and substituted ethynyl groups. The resulting polymers are cured up to 350.degree. C. to provide crosslinked poly(arylene ether)s with good solvent resistance, high strength and modulus.
Poly(arylene ether)s containing pendent ethynyl groups
NASA Technical Reports Server (NTRS)
Hergenrother, Paul M. (Inventor); Jensen, Brian J. (Inventor)
1994-01-01
Poly(arylene ether)s containing pendent ethynyl and substituted ethynyl groups and poly(arylene ether) copolymers containing pendent ethynyl and substituted ethynyl groups are readily prepared from bisphenols containing ethynyl and substituted ethynyl groups. The resulting polymers are cured up to 350 C to provide crosslinked poly(arylene ether)s with good solvent resistance, high strength and modulus.
Radiolabeled cholesteryl ethers: A need to analyze for biological stability before use.
Manual Kollareth, Denny Joseph; Chang, Chuchun L; Hansen, Inge H; Deckelbaum, Richard J
2018-03-01
Radiolabeled cholesteryl ethers are widely used as non-metabolizable tracers for lipoproteins and lipid emulsions in a variety of in vitro and in vivo experiments. Since cholesteryl ethers do not leave cells after uptake and are not hydrolyzed by mammalian cellular enzymes, these compounds can act as markers for cumulative cell uptakes of labeled particles. We have employed [ 3 H]cholesteryl oleoyl ether to study the uptake and distribution of triglyceride-rich emulsion particles on animal models. However, questionable unexpected results compelled us to analyze the stability of these ethers. We tested the stability of two commercially available radiolabeled cholesteryl ethers - [ 3 H]cholesteryl oleoyl ether and [ 3 H]cholesteryl hexadecyl ether from different suppliers, employing in vitro , in vivo and chemical model systems. Our results show that, among the two cholesteryl ethers tested, one ether was hydrolyzed to free cholesterol in vitro , in vivo and chemically under alkaline hydrolyzing agent. Free cholesterol, unlike cholesteryl ether, can then re-enter the circulation leading to confounding results. The other ether was not hydrolyzed to free cholesterol and remained as a stable ether. Hence, radiolabeled cholesteryl ethers should be analyzed for biological stability before utilizing them for in vitro or in vivo experiments.
Tush, Daniel; Meyer, Michael T
2016-06-07
Polyoxyethylene tallow amine (POEA) is an inert ingredient added to formulations of glyphosate, the most widely applied agricultural herbicide. POEA has been shown to have toxic effects to some aquatic organisms making the potential transport of POEA from the application site into the environment an important concern. This study characterized the adsorption of POEA to soils and assessed its occurrence and homologue distribution in agricultural soils from six states. Adsorption experiments of POEA to selected soils showed that POEA adsorbed much stronger than glyphosate; calcium chloride increased the binding of POEA; and the binding of POEA was stronger in low pH conditions. POEA was detected on a soil sample from an agricultural field near Lawrence, Kansas, but with a loss of homologues that contain alkenes. POEA was also detected on soil samples collected between February and early March from corn and soybean fields from ten different sites in five other states (Iowa, Illinois, Indiana, Missouri, Mississippi). This is the first study to characterize the adsorption of POEA to soil, the potential widespread occurrence of POEA on agricultural soils, and the persistence of the POEA homologues on agricultural soils into the following growing season.
Tush, Daniel L.; Meyer, Michael T.
2016-01-01
Polyoxyethylene tallow amine (POEA) is an inert ingredient added to formulations of glyphosate, the most widely applied agricultural herbicide. POEA has been shown to have toxic effects to some aquatic organisms making the potential transport of POEA from the application site into the environment an important concern. This study characterized the adsorption of POEA to soils and assessed its occurrence and homologue distribution in agricultural soils from six states. Adsorption experiments of POEA to selected soils showed that POEA adsorbed much stronger than glyphosate; calcium chloride increased the binding of POEA; and the binding of POEA was stronger in low pH conditions. POEA was detected on a soil sample from an agricultural field near Lawrence, Kansas, but with a loss of homologues that contain alkenes. POEA was also detected on soil samples collected between February and early March from corn and soybean fields from ten different sites in five other states (Iowa, Illinois, Indiana, Missouri, Mississippi). This is the first study to characterize the adsorption of POEA to soil, the potential widespread occurrence of POEA on agricultural soils, and the persistence of the POEA homologues on agricultural soils into the following growing season.
Reversibility between glass and melting transitions of poly(oxyethylene)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Qui, Wulin; Pyda, Marek; Nowak-Pyda, Elisabieta
2005-01-01
The heat capacities, C{sub p}, of poly(oxyethylene), POE, with molar masses from 1500 to 900,000 Da, were analyzed by differential scanning calorimetry (DSC), quasi-isothermal, temperature-modulated DSC (TMDSC), and wide-angle X-ray diffraction (WAXD). There is no change in crystal structure before melting, but the lattice parameters increase rapidly in the melting region. Perfected extended-chain and once- or twice-folded crystals of the oligomers with a molar mass above 1100 Da melt practically fully irreversibly and permit direct measurement of the thermodynamic C{sub p}. The folded-chain crystals of high molar mass show some locally reversible melting. The reversing, apparent C{sub p} depends onmore » molar mass and amplitude and frequency of modulation. After separation from the latent heat effects, the reversible, thermodynamic C{sub p} depends on the melting temperature for low molar masses and increases beyond the vibrational C{sub p} due to conformational motion. Molar masses of 8000-20,000 have almost the same C{sub p}. These observations permit a quantitative discussion of the thermodynamic C{sub p} and the locally reversible melting of the globally metastable POE in the melting range. The increase in C{sub p} between 250 K and the melting temperature is interpreted as a glass transition within the crystal.« less
Human cholestatic hepatitis owing to polyoxyethylene nonylphenol ingestion
Min, Jihye; Han, Joohye; Kim, Kyungju; Park, Samel; Lee, Sunhyo; Hong, Jungrak; Gil, Hyowook; Song, Hoyeon; Hong, Saeyong
2017-01-01
Abstract Rationale: The purpose of this study was to identify the chemical responsible for cholestatic hepatitis in a 55-year-old woman who ingested 1,1′-iminodi (octamethylene) diguanidinium triacetate (iminoctadine triacetate), a fungicide. The fungicide formulation was also composed of polyoxyethylene nonylphenol (NP-40) and methanol. Patient concerns: Severe cholestatic hepatitis developed, which led to the patient's death on day 88 of hospitalization. Post-mortem necropsy of the liver showed focal hepatocyte necrosis involving mostly the mid-zone, along with intracytoplasmic and intracanalicular cholestasis. Diagnoses: To identify the chemical responsible for hepatic injury, the cellular toxicity of all chemicals in the fungicide formulation was assessed in HepG2 cells using the 3-(4,5-dimethylthiaxol-2yl)-2, 5-diphenyl tetrazolium bromide test. Outcomes: Viability of cells treated with the surfactant NP-40 was significantly lower (P < .001), but that of cells treated with other components of the fungicide, including the active ingredient, iminoctadine triacetate, was unaffected. Fluorescence-activated cell sorting analysis confirmed that necrosis was induced in HepG2 cells treated with 25–80 μM of NP-40, while significant numbers of apoptotic cells were not detected. Lessons: NP-40 appears to be the chemical responsible for the patient's irreversible hepatic injury, accompanied by intracytoplasmic and intracanalicular cholestasis. PMID:28796059
Matsui, Rakan; Ueda, Osamu; Uchida, Shinya; Namiki, Noriyuki
2015-06-01
The aim of this study was to evaluate the in vitro skin permeation and in vivo transdermal absorption of natural progesterone (Prog) from alcoholic gel-based transdermal formulations containing Prog dissolved stably at a concentration of 3%. 3% Prog dissolved gel formulations were prepared containing with water, ethanol, 1,3-butylene glycol, carboxyvinylpolymer, diisopropanolamine, polyoxyethylene (2) oleylether and benzyl alcohol. The gel formulations added different hydrophilic surfactants and isopropyl myristate or propylene glycol dicaprylate (PGDC) as oily solvents were applied in vitro permeation study through excised rat skin on unocclusive condition. The gel formulations added polyoxyethylene (20) oleylether (Oleth-20) as hydrophilic surfactant and PGDC were applied in vivo single- and repeated-dose transdermal absorption study of rat on unocclusive condition. The results of evaluation of the gel formulations by an in vitro skin permeation study revealed a high flux of Prog from the formulation containing Oleth-20 and Oleth-20 with PGDC. The results of single and repeated in vivo transdermal absorption studies confirmed that good plasma levels of Prog were achieved and maintained by Oleth-20 and PGDC containing gel formulation. The Oleth-20 and PGDC containing ethanolic gel formulation seemed to have the ability to maintain a high activity of Prog and high diffusivity or solubility of Prog in the epidermis on the practical formulation application.
NASA Technical Reports Server (NTRS)
Jaffe, Richard; Han, Jie; Yoon, Do; Langhoff, Stephen R. (Technical Monitor)
1997-01-01
The so-called oxygen gauche effect in poly(oxyethylene) (POE) and its model molecules such as 1,2-dimethoxyethane (DME) and diglyme (CH3OC2H4OC2H4OCH3) is manifested in the preference for gauche C-C bond conformations over trans. This has also been observed for poly(ethylene terephthalate) (PET). Our previous quantum chemistry calculations demonstrated that the large C-C gauche population in DME is due, in part, to a low-lying tg +/- g+ conformer that exhibits a substantial 1,5 CH ... O attraction. New calculations will be described that demonstrate the accuracy of the original quantum chemistry calculations. In addition, an extension of this work to model molecules for PET will be presented. It is seen that the C-C gauche preference is much stronger in 1,2 diacetoxyethane than in DME. In addition, there exist low-lying tg +/- g+/- and g+/-g+/-g+/- conformers that exhibit 1,5 CH ... O attractions involving the carbonyl oxygens. It is expected that the -O-C-C-O- torsional properties will be quite different in these two polymers. The quantum chemistry results are used to parameterize rotational isomeric states models (RIS) and force fields for molecular dynamics simulations of these polymers.
1991-03-01
gram of —> Triton X-405 (70%) and 0.5 gram sodium lauryl sulfate . After a nitrogen -3- /- „, y-iu/iouitj Cod*s Avail and/oh ’t , • Special...period of several hours and d) using a redox system comprising of additional persulfate and a reducing agent such as sodium bisulfite or sodium
75 FR 56101 - Lauryl Sulfate Salts Registration Review Final Decision; Notice of Availability
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-15
... intended function without causing unreasonable adverse effects on human health or the environment. Through... other knowledge, including its effects on human health and the environment. FOR FURTHER INFORMATION... may be of interest to a wide range of stakeholders including environmental, human health, farm worker...
21 CFR 177.1210 - Closures with sealing gaskets for food containers.
Code of Federal Regulations, 2011 CFR
2011-04-01
... cetyl sulfate 1 percent. Sodium decylbenzenesulfonate Do. Sodium decyl sulfate Do. Sodium formaldehyde sulfoxylate 0.05 percent. Sodium lauryl sulfate 1 percent. Sodium lignin sulfonate 0.2 percent. Sodium myristyl sulfate (sodium tetradecyl sulfate) 0.6 percent. Sodium nitrite 0.2 percent; for use only in...
40 CFR 141.21 - Coliform sampling.
Code of Federal Regulations, 2011 CFR
2011-07-01
... transit. 3 Lactose broth, as commercially available, may be used in lieu of lauryl tryptose broth, if the... total coliform, using lactose broth, is less than 10 percent. 4 If inverted tubes are used to detect gas... negative-rates may be based on lactose fermentation, the rapid test for β-galactosidase and cytochrome...
40 CFR 141.21 - Coliform sampling.
Code of Federal Regulations, 2010 CFR
2010-07-01
... transit. 3 Lactose broth, as commercially available, may be used in lieu of lauryl tryptose broth, if the... total coliform, using lactose broth, is less than 10 percent. 4 If inverted tubes are used to detect gas... negative-rates may be based on lactose fermentation, the rapid test for β-galactosidase and cytochrome...
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...
Huh, Yoon Ho; Bae, In-Gon; Jeon, Hong Goo; Park, Byoungchoo
2016-10-31
We herein report a homogeneous [6,6]-phenyl C61 butyric acid methyl ester (PCBM) layer, produced by a solution process of horizontal-dipping (H-dipping) to improve the photovoltaic (PV) effects of bilayer heterojunction organic photovoltaic cells (OPVs) based on a bi-stacked poly(3-hexylthiophene) (P3HT) electron donor layer and a PCBM electron acceptor layer (P3HT/PCBM). It was shown that a homogeneous and uniform coating of PCBM layers in the P3HT/PCBM bilayer OPVs resulted in reliable and reproducible device performance. We recorded a power conversion efficiency (PCE) of 2.89%, which is higher than that (2.00%) of bilayer OPVs with a spin-coated PCBM layer. Moreover, introducing surfactant additives of poly(oxyethylene tridecyl ether) (PTE) into the homogeneous P3HT/PCBM PV layers resulted in the bilayer OPVs showing a PCE value of 3.95%, which is comparable to those of conventional bulk-heterojunction (BHJ) OPVs (3.57-4.13%) fabricated by conventional spin-coating. This improved device performance may be attributed to the selective collection of charge carriers at the interfaces among the active layers and electrodes due to the PTE additives as well as the homogeneous formation of the functional PCBM layer on the P3HT layer. Furthermore, H-dip-coated PCBM layers were deposited onto aligned P3HT layers by a rubbing technique, and the rubbed bilayer OPV exhibited improved in-plane anisotropic PV effects with PCE anisotropy as high as 1.81, which is also higher than that (1.54) of conventional rubbed BHJ OPVs. Our results suggest that the use of the H-dip-coating process in the fabrication of PCBM layers with the PTE interface-engineering additive could be of considerable interest to those seeking to improve PCBM-based opto-electrical organic thin-film devices.
Tang, Jian; Qu, Zhou; Luo, Jianhui; He, Lanyan; Wang, Pingmei; Zhang, Ping; Tang, Xianqiong; Pei, Yong; Ding, Bin; Peng, Baoliang; Huang, Yunqing
2018-02-15
The detachment process of an oil molecular layer situated above a horizontal substrate was often described by a three-stage process. In this mechanism, the penetration and diffusion of water molecules between the oil phase and the substrate was proposed to be a crucial step to aid in removal of oil layer/drops from substrate. In this work, the detachment process of a two-dimensional alkane molecule layer from a silica surface in aqueous surfactant solutions is studied by means of molecular dynamics (MD) simulations. By tuning the polarity of model silica surfaces, as well as considering the different types of surfactant molecules and the water flow effects, more details about the formation of water molecular channel and the expansion processes are elucidated. It is found that for both ionic and nonionic type surfactant solutions, the perturbation of surfactant molecules on the two-dimensional oil molecule layer facilitates the injection and diffusion of water molecules between the oil layer and silica substrate. However, the water channel formation and expansion speed is strongly affected by the substrate polarity and properties of surfactant molecules. First, only for the silica surface with relative stronger polarity, the formation of water molecular channel is observed. Second, the expansion speed of the water molecular channel upon the ionic surfactant (dodecyl trimethylammonium bromide, DTAB and sodium dodecyl benzenesulfonate, SDBS) flooding is more rapidly than the nonionic surfactant system (octylphenol polyoxyethylene(10) ether, OP-10). Third, the water flow speed may also affect the injection and diffusion of water molecules. These simulation results indicate that the water molecular channel formation process is affected by multiple factors. The synergistic effects of perturbation of surfactant molecules and the electrostatic interactions between silica substrate and water molecules are two key factors aiding in the injection and diffusion of water molecules and helpful for the oil detachment from silica substrate.
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.
Anticancer Therapeutic Potential of VEGI, an Antiangiogenic Cytokine
2002-10-01
PCR product. The blots were hybridized at 42°C overnight and washed in wash buffer 1 ( 2 x SSC, 0.1% sodium lauryl sulfate ) and wash buffer 2 (1 x SSC...transfected into MDA- MIB-231 breast cancer cells by electroporation. Stable transfectants were selected in 2 mg/ml G418 sulfate (Invitrogen). Conditioned
The Polar and Electrical Nature of Dye Binding Sites on Human Red Blood Cell Membranes.
positive charges at the binding sites. By increasing the concentration of the anionic BPB (or by the addition of the anionic detergent sodium lauryl ... sulfate ) these positive charges appear to be successively titrated, rendering the membrane binding sites electrically neutral at this pH. The average
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-30
... function without unreasonable adverse effects on human health or the environment. Through this program, EPA..., including its effects on human health and the environment. DATES: Comments must be received on or before... interest to a wide range of stakeholders including environmental, human health, farm worker, and...
21 CFR 172.822 - Sodium lauryl sulfate.
Code of Federal Regulations, 2012 CFR
2012-04-01
... acid-acidulated dry beverage base whereby the additive does not exceed 25 parts per million of the finished beverage and such beverage base is not for use in a food for which a standard of identity established under section 401 of the Act precludes such use. (ii) Fumaric acid-acidulated fruit juice drinks...
Lee, E J; Rothwell, J T
2010-04-01
To characterise the changes caused to sheep skin by deep dermal and subcutaneous injections of sodium lauryl sulfate (SLS) and describe the subsequent healing process. On 6 sheep 20 small areas of skin were each given deep dermal and subcutaneous injections of 0.2 mL of 7% SLS. Biopsies were collected at intervals up to 28 days after treatment and the histological changes in each of the treated skin samples were assessed and graded. There was no evidence of alterations in behaviour, weight gain or appetite of the sheep following the injections. Initial swelling of the treated site subsided by day 14, leaving a firm, slightly raised crust. At day 21, the treated area was depressed and covered by a scab, which sloughed completely by day 28. There was necrosis of the subcutis and deep dermis 2 min after treatment, followed by inflammation, fibroplasia, angiogenesis and tissue remodelling. Injection of SLS caused almost immediate local necrosis followed by eschar formation, sloughing and scarring of treated skin. Deep dermal and subcutaneous SLS is potentially useful as a chemical alternative to mulesing.
Usefulness of addition of Orvus ES paste and sodium lauryl sulfate to frozen feline semen.
Mizutani, Tatsuji; Sumigama, Shiho; Nagakubo, Keiichi; Shimizu, Noriko; Oba, Hiromichi; Hori, Tatsuya; Tsutsui, Toshihiko
2010-01-01
It has been shown that addition of the surfactant Orvus ES paste (OEP) and its main component sodium lauryl sulfate (SLS) to boar or dog semen before freezing improves post-thaw sperm motility and protects acrosome caps. In this study, we investigated the usefulness of the addition of OEP (0, 1, 2 and 4%) or SLS (0, 1, 2, 3 and 4 mg/ml) to cat ejaculates before freezing and their concentrations. Among the OEP addition groups, the 1% OEP group showed higher sperm motility than the other groups. Among the SLS addition groups, the 3 mg/ml SLS group showed slightly higher sperm motility and viability than the other groups. Comparison between the 1% OEP and 3 mg/ml SLS addition groups suggested a higher percentage of sperm with an acrosome cap in the 1% OEP group. The other sperm properties did not significantly differ between the 2 groups. These results indicate that addition of 1% OEP or 3 mg/ml SLS is effective for freezing of cat ejaculated semen.
Aburub, Aktham; Risley, Donald S; Mishra, Dinesh
2008-01-22
The aim of this work is to evaluate one of the most commonly used fasted state simulating gastric fluids (FaSSGFs), which contains sodium lauryl sulfate (SLS) (FaSSGF(SLS)), and propose a more appropriate surfactant concentration. Surface tension studies clearly show that the critical micelle concentration (CMC) of SLS in the relevant media (a media whose pH and sodium chloride concentration are representative of physiological conditions) is significantly lower (p<0.05) than 8.67 mM, which is the SLS concentration in FaSSGF(SLS). The CMC of SLS in the relevant media was determined to be 1.75 mM. Based on this a modified recipe is proposed in which the concentration of SLS is sufficient to achieve a surface tension similar to that in vivo without causing artificial micellar solubilization. Solubility, intrinsic dissolution, and GastroPlus modeling studies are presented to support and give rationale for the modified recipe. In addition, a comparison between the modified recipe and other FaSSGFs reported in the literature is made.
Fuchs, S M; Schliemann-Willers, S; Fischer, T W; Elsner, P
2005-01-01
In the present study, we evaluated the protective action of cream preparations containing seven different types of marigold and rosemary extracts in vivo in healthy volunteers with experimentally induced irritant contact dermatitis (ICD). Marigold and rosemary extracts in base cream DAC (Deutscher Arzneimittel-Codex = German Pharmaceutical Codex) were tested in a 4-day repetitive irritation test using sodium lauryl sulfate. The effect was evaluated visually and quantified by noninvasive bioengineering methods, namely chromametry and tewametry. When the test products were applied parallel to the induction period of ICD, a statistically significant protective effect of all cream preparations was observed by all methods. This effect, although not statistically significant, was superior to control by undyed marigold und faradiol ester-enriched extracts in chromametry and by dyed and undyed rosemary extracts in tewametry. The sequential treatment (postirritation) once a day for 5 days was without any effect. Thus, a protective effect of some marigold and rosemary extracts against ICD could be shown in the elicitation phase. Copyright (c) 2005 S. Karger AG, Basel.
New nanocomposites of polystyrene with polyaniline doped with lauryl sulfuric acid
NASA Astrophysics Data System (ADS)
Pud, A. A.; Nikolayeva, O. A.; Vretik, L. O.; Noskov, Yu. V.; Ogurtsov, N. A.; Kruglyak, O. S.; Fedorenko, E. A.
2017-08-01
This work is concentrated on synthesis and investigation of new core-shell nanocomposites of polystyrene (PS) with doped polyaniline (PANI). The latex containing PS nanoparticles with sizes of 15-30 nm was prepared by microemulsion polymerization of styrene in water media. The PS/PANI nanocomposites were synthesized by chemical oxidative polymerization of aniline in the PS latex media in a presence of lauryl sulfuric acid (LSA), which served as both dopant and plasticizer. The real content of PANI in the synthesized nanocomposites was determined by UV-Vis spectroscopy method. The composition of the nanocomposites and oxidation state of the doped polyaniline were characterized by FTIR spectroscopy. The core-shell morphology of the nanocomposite nanoparticles was proved by transmission and scanning electron microscopy. It was found that conductivity and thermal behavior in air of these nanocomposites not only nonlinearly depended on the doped polyaniline content but also were strongly effected both by plasticizing properties of the acid-dopant and presence of the polyaniline shell. A possibility of application of these nanocomposites as sensor materials has been demonstrated.
Matsumiya, Y; Murata, N; Tanabe, E; Kubota, K; Kubo, M
2010-06-01
To degrade ether-type polyurethane (ether-PUR), ether-PUR-degrading micro-organism was isolated. Moreover, ether-PUR-degrading mechanisms were analysed using model compounds of ether-PUR. A fungus designated as strain PURDK2, capable of changing the configuration of ether-PUR, has been isolated. This isolated fungus was identified as Alternaria sp. Using a scanning electron microscope, the grid structure of ether-PUR was shown to be melted and disrupted by the fungus. The degradation of ether-PUR by the fungus was analysed, and the ether-PUR was degraded by the fungus by about 27.5%. To analyse the urethane-bond degradation by the fungus, a degraded product of ethylphenylcarbamate was analysed using GC/MS. Aniline and ethanol were detected by degradation with the supernatant, indicating that the fungus secreted urethane-bond-degrading enzyme(s). PURDK2 also degraded urea bonds when diphenylmethane-4,4'-dibutylurea was used as a substrate. The enzyme(s) from PURDK2 degraded urethane and urea bonds to convert the high molecular weight structure of ether-PUR to small molecules; and then the fungus seems to use the small molecules as an energy source. Ether-PUR-degrading fungus, strain PURDK2, was isolated, and the urethane- and urea-bonds-degrading enzymes from strain PURDK2 could contribute to the material recycling of ether-PUR.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
Phillips Petroleum Co. is poised to license its high conversion process to produce fuel ethers for blending in reformulated gasolines. The technology has been proven in a Phillips semiworks at Bartlesville, Okla. The process can produce methyl tertiary butyl ether, ethyl tertiary butyl ether, tertiary amyl methyl ether, or tertiary amyl ethyl ether with typical refinery process equipment and techniques. Phillips said it can achieve conversion levels of 92-99%, depending on the ether. The ether produced is determined by which hydrocarbon fraction is used for feedstock and which alcohol is chosen for reaction. The process is described.
A new route to synthesize aryl acetates from carbonylation of aryl methyl ethers
Yang, Youdi; Li, Shaopeng; Han, Buxing
2018-01-01
Ether bond activation is very interesting because the synthesis of many valuable compounds involves conversion of ethers. Moreover, C–O bond cleavage is also very important for the transformation of biomass, especially lignin, which abundantly contains ether bonds. Developing efficient methods to activate aromatic ether bonds has attracted much attention. However, this is a challenge because of the inertness of aryl ether bonds. We proposed a new route to activate aryl methyl ether bonds and synthesize aryl acetates by carbonylation of aryl methyl ethers. The reaction could proceed over RhCl3 in the presence of LiI and LiBF4, and moderate to high yields of aryl acetates could be obtained from transformation of various aryl methyl ethers with different substituents. It was found that LiBF4 could assist LiI to cleave aryl methyl ether bonds effectively. The reaction mechanism was proposed by a combination of experimental and theoretical studies. PMID:29795781
Mizutani, Taeko; Mori, Ryota; Hirayama, Misaki; Sagawa, Yuki; Shimizu, Kenji; Okano, Yuri; Masaki, Hitoshi
2016-12-01
Sodium lauryl sulfate (SLS), a representative anionic surfactant, is well-known to induce rough skin following single or multiple topical applications. The mechanism by which SLS induces rough skin is thought to result from the disruption of skin moisture function consisting of NMF and epidermal lipids. However, a recent study demonstrated that topically applied SLS easily penetrates into the living cell layers of the epidermis, which suggests that physiological alterations of keratinocytes might cause the SLS-induced rough skin. This study was conducted to clarify the effects of SLS on keratinocytes to demonstrate the contribution of SLS to the induction of rough skin. In addition, the potentials of other widely used anionic surfactants to induce rough skin were evaluated. HaCaT keratinocytes treated with SLS had increased levels of intracellular ROS and IL-1α secretion. Application of SLS on the surface of a reconstructed epidermal equivalent also showed the increased generation of ROS. Further, SLS-treated cells showed an increase of intracellular calpain activity associated with the increase of intracellular Ca 2+ concentration. The increase of intracellular ROS was abolished by the addition of BAPTA-AM, a specific chelator of Ca 2+ . In addition, IL-1α also stimulated ROS generation by HaCaT keratinocytes. An ESR spin-labeling study demonstrated that SLS increased the fluidity of membranes of liposomes and cells. Together, those results indicate that SLS initially interacts with cell membranes, which results in the elevation of intracellular Ca 2+ influx. Ca 2+ stimulates the secretion of IL-1α due to the activation of calpain, and also increases ROS generation. IL-1α also stimulates ROS generation by HaCaT keratinocytes. We conclude from these results that the elevation of intracellular ROS levels is one of the causes of SLS-induced rough skin. Finally, among the other anionic surfactants tested, sodium lauryl phosphate has less potential to induce rough skin because of its lower generation of ROS.
Catalytic oxidation of dimethyl ether
Zelenay, Piotr; Wu, Gang; Johnston, Christina M.; Li, Qing
2016-05-10
A composition for oxidizing dimethyl ether includes an alloy supported on carbon, the alloy being of platinum, ruthenium, and palladium. A process for oxidizing dimethyl ether involves exposing dimethyl ether to a carbon-supported alloy of platinum, ruthenium, and palladium under conditions sufficient to electrochemically oxidize the dimethyl ether.
Palladium-Catalyzed Reductive Insertion of Alcohols into Aryl Ether Bonds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Meng; Gutiérrez, Oliver Y.; Camaioni, Donald M.
Pd/C catalyzes C-O bond cleavage of aryl ethers (diphenyl ether and cyclohexyl phenyl ether) by methanol in H2. The aromatic C-O bond is cleaved by reductive methanolysis, which is initiated by Pd-catalyzed partial hydrogenation of one phenyl ring to form an enol ether. The enol ether reacts rapidly with methanol to form a ketal, which generates methoxycyclohexene by eliminating phenol or an alkanol. Subsequent hydrogenation leads to methoxycyclohexane.
Liu, H; Agishi, T; Kawai, T; Hayashi, T; Fujita, S; Fuchinoue, S; Takahashi, K; Teraoka, S; Ota, K
1992-01-01
A new type of artificial blood, pyridoxylated hemoglobin-polyoxyethylene conjugate (PHP) solution, (developed by PHP research group of the department of health and welfare of Japan, and produced by Ajinomoto Co., Inc. Tokyo) as an oxygen-carrying component, has been recently devised using hemoglobin obtained from hemolyzed human erythrocytes. Recently, the studies using this solution as a preservation solution were performed in some instances. To examine the mechanism of improved viability using this solution as a preservation solution, we developed a model of orthotopic small intestine transplantation (OIT) in the rat. As a baseline study, we compared parameters of viability of the grafts preserved in Collins and UW solution to those preserved in PHP solution including a survival rate, a serum level total protein and albumin, and a change in body weight after transplantation. In our study, the simple hypothermia storage together with intestinal perfusion preservation with PHP solution was performed. Animals were divided into 6, 12, and 24 hr preservation groups. All of the rats survived after 6 hr preservation following transplantation. However, in 12 hr storage, five of six rats in PHP solution preservation survived and recovery in body weight after grafting was better than those with Collins and UW solution. We conclude that the PHP solution is, therefore, considered to possibly be a more suitable perfusate for small intestine preservation than Collins and UW solution.
NASA Astrophysics Data System (ADS)
Guigas, Claudia; Walz, Elke; Gräf, Volker; Heller, Knut J.; Greiner, Ralf
2017-06-01
The potential of engineered nanomaterials to induce genotoxic effects is an important aspect of hazard identification. In this study, cytotoxicity and mutagenicity as a function of metabolic activation of three silver nanoparticle (AgNP) preparations differing in surface coating were determined in Chinese hamster ovary (CHO) subclone K1 cells. Three silver nanoparticle preparations ( x 90,0 <30 nm) stabilized with polyoxyethylene glycerol trioleate and polyoxyethylene sorbitan monolaurate (AgPure™), citrate (Citrate-Ag), and polyvinylpyrrolidone (PVP-Ag) were used for the experiments. The cytotoxic effect of AgNPs was assessed with the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide) test using different concentrations of nanoparticles, while the mutagenicity was evaluated using the hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene mutation assay. The cytotoxicity of all three AgNPs was lower in a cell culture medium containing 10% fetal calf serum (FCS) than in medium without FCS. The HPRT test without metabolic activation system S9 revealed that compared to the other AgNP formulations, citrate-coated Ag showed a lower genotoxic effect. However, addition of S9 increased the mutation frequency of all AgNPs and especially influenced the genotoxicity of Citrate-Ag. The results showed that exogenous metabolic activation of nanosilver is crucial even if interactions of the metabolic activation system, nanosilver, and cells are not really understood up to now.
Using relative rate methods, rate constants for the gas-phase reactions of OH radicals and Cl atoms with di-n-propyl ether, di-n-propyl ether-d14, di-n-butyl ether and di-n-butyl ether-d18 have been measured at 296 ? 2 K and atmos...
NIOSH Manual of Analytical Methods (third edition). Fourth supplement
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1990-08-15
The NIOSH Manual of Analytical Methods, 3rd edition, was updated for the following chemicals: allyl-glycidyl-ether, 2-aminopyridine, aspartame, bromine, chlorine, n-butylamine, n-butyl-glycidyl-ether, carbon-dioxide, carbon-monoxide, chlorinated-camphene, chloroacetaldehyde, p-chlorophenol, crotonaldehyde, 1,1-dimethylhydrazine, dinitro-o-cresol, ethyl-acetate, ethyl-formate, ethylenimine, sodium-fluoride, hydrogen-fluoride, cryolite, sodium-hexafluoroaluminate, formic-acid, hexachlorobutadiene, hydrogen-cyanide, hydrogen-sulfide, isopropyl-acetate, isopropyl-ether, isopropyl-glycidyl-ether, lead, lead-oxide, maleic-anhydride, methyl-acetate, methyl-acrylate, methyl-tert-butyl ether, methyl-cellosolve-acetate, methylcyclohexanol, 4,4'-methylenedianiline, monomethylaniline, monomethylhydrazine, nitric-oxide, p-nitroaniline, phenyl-ether, phenyl-ether-biphenyl mixture, phenyl-glycidyl-ether, phenylhydrazine, phosphine, ronnel, sulfuryl-fluoride, talc, tributyl-phosphate, 1,1,2-trichloro-1,2,2-trifluoroethane, trimellitic-anhydride, triorthocresyl-phosphate, triphenyl-phosphate, and vinyl-acetate.
Drechsler, Robin; Chen, Shaw-Wen; Dancy, Blair C. R.; Mehrabkhani, Lena
2016-01-01
Despite the fact that the discovery of ether-linked phospholipids occurred nearly a century ago, many unanswered questions remain concerning these unique lipids. Here, we characterize the ether-linked lipids of the nematode with HPLC-MS/MS and find that more than half of the phosphoethanolamine-containing lipids are ether-linked, a distribution similar to that found in mammalian membranes. To explore the biological role of ether lipids in vivo, we target fatty acyl-CoA reductase (fard-1), an essential enzyme in ether lipid synthesis, with two distinct RNAi strategies. First, when fard-1 RNAi is initiated at the start of development, the treated animals have severely reduced ether lipid abundance, resulting in a shift in the phosphatidylethanolamine lipid population to include more saturated fatty acid chains. Thus, the absence of ether lipids during development drives a significant remodeling of the membrane landscape. A later initiation of fard-1 RNAi in adulthood results in a dramatic reduction of new ether lipid synthesis as quantified with 15N-tracers; however, there is only a slight decrease in total ether lipid abundance with this adult-only fard-1 RNAi. The two RNAi strategies permit the examination of synthesis and ether lipid abundance to reveal a relationship between the amount of ether lipids and stress survival. We tested whether these species function as sacrificial antioxidants by directly examining the phospholipid population with HPLC-MS/MS after oxidative stress treatment. While there are significant changes in other phospholipids, including polyunsaturated fatty acid-containing species, we did not find any change in ether-linked lipids, suggesting that the role of ether lipids in stress resistance is not through their general consumption as free radical sinks. Our work shows that the nematode will be a useful model for future interrogation of ether lipid biosynthesis and the characterization of phospholipid changes in various stress conditions. PMID:27893806
1975-02-01
alkyl lauryl sulfate added as a wet^ng agent. Routine sterilization of air locks and material entering the isolators was done with 2.OX peracetic...flexible plastic isolators of the Trexler type (19). The isolators were sterilized with 4.0% peracetic acid in water with a small amount of sodium
Oil-soluble hairy nanoparticles as lubricant additives
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, Bin
Oil-soluble polymer brush-grafted nanoparticles (hairy NPs) were synthesized by surface-initiated atom transfer radical polymerization of lauryl methacrylate from initiator-functionalized silica nanoparticles and used as an additive for polyalphaolefin (PAO) for friction and wear reduction. Addition of 1 wt% hairy nanoparticles into PAO led to significant friction and wear reduction compared with PAO base oil.
Fisher, Darrell R.; Wai, Chien M.; Chen, Xiaoyuan
2000-01-01
The invention pertains to compounds which specifically bind radionuclides, and to methods of making radionuclide complexing compounds. In one aspect, the invention includes a radionuclide delivery system comprising: a) a calix[n]arene-crown-[m]-ether compound, wherein n is an integer greater than 3, and wherein m is an integer greater than 3, the calix[n]arene-crown-[m]-ether compound comprising at least two ionizable groups; and b) an antibody attached to the calix[n]arene-crown-[m]-ether compound. In another aspect, the invention includes a method of making a radium complexing compound, comprising: a) providing a calix[n]arene compound, wherein n is an integer greater than 3, the calix[n]arene compound comprising n phenolic hydroxyl groups; b) providing a crown ether precursor, the crown ether precursor comprising a pair of tosylated ends; c) reacting the pair of tosylated ends with a pair of the phenolic hydroxyl groups to convert said pair of phenolic hydroxyl groups to ether linkages, the ether linkages connecting the crown ether precursor to the calix[n]arene to form a calix[n]arene-crown-[m]-ether compound, wherein m is an integer greater than 3; d) converting remaining phenolic hydroxyl groups to esters; e) converting the esters to acids, the acids being proximate a crown-[m]-ether portion of the calix[n]arene-crown-[m]-ether compound; and f) providing a Ra.sup.2+ ion within the crown-[m]-ether portion of the calix[n]arene-crown-[m]-ether compound.
Ma, Jie; Xiong, Desen; Li, Haiyan; Ding, Yi; Xia, Xiangcheng; Yang, Yongqi
2017-06-15
Vapor intrusion of synthetic fuel additives represents a critical yet still neglected problem at sites contaminated by petroleum fuel releases. This study used an advanced numerical model to investigate the vapor intrusion potential of fuel ether oxygenates methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), and ethyl tert-butyl ether (ETBE). Simulated indoor air concentration of these compounds can exceed USEPA indoor air screening level for MTBE (110μg/m 3 ). Our results also reveal that MTBE has much higher chance to cause vapor intrusion problems than TAME and ETBE. This study supports the statements made by USEPA in the Petroleum Vapor Intrusion (PVI) Guidance that the vertical screening criteria for petroleum hydrocarbons may not provide sufficient protectiveness for fuel additives, and ether oxygenates in particular. In addition to adverse impacts on human health, ether oxygenate vapor intrusion may also cause aesthetic problems (i.e., odour and flavour). Overall, this study points out that ether oxygenates can cause vapor intrusion problems. We recommend that USEPA consider including the field measurement data of synthetic fuel additives in the existing PVI database and possibly revising the PVI Guidance as necessary. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Jones, W. R., Jr.; Snyder, C. E., Jr.
1979-01-01
Boundary lubricating characteristics, thermal stability, and oxidation-corrosion stability were determined for a fluorinated polyether and a perfluoropolyether triazine. A ball-on-disk apparatus, a tensimeter, and oxidation-corrosion apparatus were used. Results were compared to data for a polyphenyl ether and a C-ether. The polyether and triazine yielded better boundary lubricating characteristics than either the polyphenyl ether or C-ether. The polyphenyl ether had the greatest thermal stability (443 C) while the other fluids had stabilities in the range 389 to 397 C. Oxidation-corrosion results indicated the following order of stabilities: perfluoropolyether trizine greater than polyphenyl ether greater than C-ether greater than fluorinated polyether.
Sinterable Ceramic Powders from Laser-Heated Gases.
1988-02-01
ether . carboxylic acid. and aldehyde clases: water is also included.Acrigto William and Goodman.’ a single crystalline sili- The single-crstalline...represent commonly available organic families, Including aliphatic and aromatic hydrocarbons, chlorides, ethers , ketones , esters, alcohols, aldehydes...Hydrocarbons Ketone Amine Chlorides Low-alcohols 8f . Ether Ester - _Aldehyde Ether Ketones High-alcohols 04 Carboxylic Ester I acid Ether o . Nitrile
Moreno Horn, Marcus; Garbe, Leif-Alexander; Tressl, Roland; Adrian, Lorenz; Görisch, Helmut
2003-04-01
Rhodococcus sp. strain DTB (DSM 44534) grows on bis(1-chloro-2-propyl) ether (DDE) as sole source of carbon and energy. The non-chlorinated diisopropyl ether and bis(1-hydroxy-2-propyl) ether, however, did not serve as substrates. In ether degradation experiments with dense cell suspensions, 1-chloro-2-propanol and chloroacetone were formed, which indicated that scission of the ether bond is the first step while dehalogenation of the chlorinated C(3)-compounds occurs at a later stage of the degradation pathway. Inhibition of ether scission by methimazole suggested that the first step in degradation is catalyzed by a flavin-dependent enzyme activity. The non-chlorinated compounds 1,2-propanediol, hydroxyacetone, lactate, pyruvate, 1-propanol, propanal, and propionate also supported growth, which suggested that the intermediates 1,2-propanediol and hydroxyacetone are converted to pyruvate or to propionate, which can be channeled into the citric acid cycle by a number of routes. Total release of chloride and growth-yield experiments with DDE and non-chlorinated C(3)-compounds suggested complete biodegradation of the chlorinated ether.
Some actions of substituted choline phenyl ethers, particularly of choline 2:6-xylyl ether
Edge, N. D.; Mason, D. F. J.; Wyllie, J. H.
1957-01-01
Marked nicotine-like stimulant properties are possessed by choline phenyl ether and choline o-tolyl ether, and to a decreasing extent by choline 2:6-xylyl ether and choline 2:4:6-mesityl ether. The compounds all show neuromuscular blocking properties, which are of short duration and pass from mainly decamethonium-like to mainly curare-like as more methyl groups are added to the phenyl nucleus. This series of compounds also possesses muscarinic, weak anti-adrenaline and vasodilator properties, as well as long-lasting local anaesthetic effects in the two compounds tested by intradermal injection. PMID:13460236
NASA Astrophysics Data System (ADS)
Mandal, Krishnagopal; Demas, J. N.
1981-12-01
Very efficient (45-75%) sodium lauryl sulfate (NaLS) enhanced singlet enengy transfer has been demonstrated from the spin-orbit charge-transfer excited state of [Ru(bpy) 3] 2+ (bpy = 2,2'-bipyridine) to the xxx violet, oxazine 1, and rhodamine 101 at concentrations of 10 -5 M, Energy transfer occurs in xxx.
Code of Federal Regulations, 2014 CFR
2014-07-01
...) Solvent Kaolinite-type clay Solid diluent, carrier Lactic acid Solvent Lactic acid, 2-ethylhexyl ester (CAS Reg. No. 6283-86-9) Solvent Lactic acid, 2-ethylhexyl ester, (2S)- (CAS Reg. No. 186817-80-1) Solvent Lactic acid, n-propyl ester, (S); (CAS Reg. No. 53651-69-7) Solvent Lauryl alcohol Surfactant...
Huang, Chun-Ming; Wang, Chao-Cheng; Kawai, Mikako; Barnes, Stephen; Elmets, Craig A
2006-03-01
The skin is a highly accessible organ and thus provides an attractive immune environment for cost-effective, simple, and needle-free delivery of vaccines and immunomodulators. In this study, we pretreated mouse skin with an anionic surfactant, sodium lauryl sulfate (SLS), for a short period of time (10 min) followed by epicutaneous vaccination with hen egg lysozyme antigen. We demonstrated for the first time that pretreatment of skin with surfactant SLS significantly enhances the production of antibody to hen egg lysozyme. Short term pretreatment with SLS disorganized the stratum corneum, extracted partial lamellar lipids, induced the maturation of Langerhans cells, and did not result in epidermis thickening. To reveal the mechanism underlying these changes, particularly at the molecular level, we used a novel proteomic technique using ultrafiltration capillaries and mass spectrometry to identify in vivo proteins/peptides secreted in the SLS-pretreated skin. Two secretory proteins, named as calcium-binding protein S100A9 and thymosin beta4, were identified by this novel technique. These two proteins thus may provide new insight into the enhancing effect of surfactants on skin vaccination.
Long-term repetitive sodium lauryl sulfate-induced irritation of the skin: an in vivo study.
Branco, Nara; Lee, Ivy; Zhai, Hongbo; Maibach, Howard I
2005-11-01
Skin may adapt to topical irritants through accommodation. This study focuses on long-term exposure to irritants and attempts to demonstrate accommodation. Sodium lauryl sulfate (SLS) induced irritant contact dermatitis at 3 concentrations (0.025% to 0.075%). Distilled water, acetone and an empty chamber served as controls. Experimental compounds were applied to forearms of 7 healthy volunteers for 24 hr before replacing by a fresh chamber for 6 non-consecutive weeks over 103 days. Possible accommodation was quantified by visual scoring (erythema and dryness) and by bioengineering parameters: transepidermal water loss (TEWL), capacitance, chromametry and laser Doppler flowmetry (LDF). Significant erythema, dryness, elevated TEWL, skin colour reflectance and LDF values occurred during the exposure periods. Upon repeat exposure, an immediate and augmented response in erythema, TEWL, skin colour reflectance and LDF developed. However, irritant skin changes were not sustained. Irritation parameters return to baseline after cessation of exposure. There was no evidence of sustained irritation or accommodation after the last exposure. Study findings do not document sustained accommodation or adaptive hyposensitivity after long-term repetitive irritant exposure under these test conditions. Alternative models should be developed to prove or disprove the accommodation hypothesis.
Taha, Mutasem O; Nasser, Wissam; Ardakani, Adel; Alkhatib, Hatim S
2008-02-28
The aim of this research is to investigate the effects of sodium lauryl sulfate (SLS) on ionotropically cross-linked alginate beads. Different levels of SLS were mixed with sodium alginate and chlorpheniramine maleate (as loaded model drug). The resulting viscous solutions were dropped onto aqueous solutions of zinc or calcium ions for ionotropic curing. The generated beads were assessed by their drug releasing profiles, infrared and differential scanning colorimetery (DSC) traits. SLS was found to exert profound concentration-dependent impacts on the characteristics of zinc-crosslinked alginate beads such that moderate modifications in the levels of SLS switched drug release from enteric coating-like behavior to a biphasic release modifiable to sustained-release by the addition of minute amounts of xanthan gum. Calcium cross-linking failed to reproduce the same behavior, probably due to the mainly ionic nature of calcium-carboxylate bonds compared to the coordinate character of their zinc-carboxylate counterparts. Apparently, moderate levels of SLS repel water penetration into the beads, and therefore minimize chlorpheniramine release. However, higher SLS levels seem to discourage polymeric cross-linking and therefore allow biphasic drug release.
Effect of sodium lauryl sulfate in dissolution media on dissolution of hard gelatin capsule shells.
Zhao, Fang; Malayev, Vyacheslav; Rao, Venkatramana; Hussain, Munir
2004-01-01
Sodium lauryl sulfate (SLS) is a commonly used surfactant in dissolution media for poorly water soluble drugs. However, it has occasionally been observed that SLS negatively impacts the dissolution of drug products formulated in gelatin capsules. This study investigated the effect of SLS on the dissolution of hard gelatin capsule shells. The USP paddle method was used with online UV monitoring at 214 nm (peptide bond). Empty size #0 capsule shells were held to the bottom of the dissolution vessel by magnetic three-prong sinkers. SLS significantly slowed down the dissolution of gelatin shells at pH < 5. Visually, the gelatin shells transformed into some less-soluble precipitate under these conditions. This precipitate was found to contain a higher sulfur content than the gelatin control sample by elemental analysis, indicating that SLS is part of the precipitate. Additionally, the slowdown of capsule shell dissolution was shown to be dependent on the SLS concentration and the ionic strength of the media. SLS interacts with gelatin to form a less-soluble precipitate at pH < 5. The use of SLS in dissolution media at acidic pH should be carefully evaluated for gelatin capsule products.
Inhibition of bacterial activity in acid mine drainage
NASA Astrophysics Data System (ADS)
Singh, Gurdeep; Bhatnagar, Miss Mridula
1988-12-01
Acid mine drainage water give rise to rapid growth and activity of an iron- and sulphur- oxidizing bacterium Thiobacillus ferrooxidians which greatly accelerate acid producing reactions by oxidation of pyrite material associated with coal and adjoining strata. The role of this bacterium in production of acid mine drainage is described. This study presents the data which demonstrate the inhibitory effect of certain organic acids, sodium benzoate, sodium lauryl sulphate, quarternary ammonium compounds on the growth of the acidophilic aerobic autotroph Thiobacillus ferrooxidians. In each experiment, 10 milli-litres of laboratory developed culture of Thiobacillus ferrooxidians was added to 250 milli-litres Erlenmeyer flask containing 90 milli-litres of 9-k media supplemented with FeSO4 7H2O and organic compounds at various concentrations. Control experiments were also carried out. The treated and untreated (control) samples analysed at various time intervals for Ferrous Iron and pH levels. Results from this investigation showed that some organic acids, sodium benzoate, sodium lauryl sulphate and quarternary ammonium compounds at low concentration (10-2 M, 10-50 ppm concentration levels) are effective bactericides and able to inhibit and reduce the Ferrous Iron oxidation and acidity formation by inhibiting the growth of Thiobacillus ferrooxidians is also discussed and presented
Dias, Tania Cristina de Sá; Baby, André Rolim; Kaneko, Telma Mary; Velasco, Maria Valéria Robles
2008-06-01
Straightening is a chemical process by which excessively curly hair is straightened in an irreversible way. Generally, products are formulated as emulsions with high pH value (9.0-12.0), which, after applied on hair, cause considerable damage, making it dry and fragile. This research work evaluated the protective effect of lauryl PEG/PPG-18/18 methicone, cyclopentasiloxane (and) PEG-12 dimethicone cross-polymer, jojoba oil, and aqua (and) cystine bis-PG propyl silanetriol, as conditioning agents, on Afro-ethnic hair locks treated with thioglycolate-based straightening emulsions by protein loss, combability, and traction to rupture. Standard Afro-ethnic hair locks were prepared following a protocol for straightening emulsion application. Considering the assays performed, the addition of conditioning agents to the straightening emulsion with ammonium thioglycolate benefited the hair fiber, thus diminishing protein loss, protecting the hair thread, and improving resistance to breakage. Jojoba oil and lauryl PEG/PPG-18/18 methicone were the conditioning agents that presented the best results. Straightening emulsions with ammonium thioglycolate containing aqua (and) cystine bis-PG propyl silanetriol and cyclopentasiloxane (and) PEG-12 dimethicone cross-polymer were the ones that provided higher breakage resistance of the thread.
Aduri, Nanda G; Ernst, Heidi A; Prabhala, Bala K; Bhatt, Shweta; Boesen, Thomas; Gajhede, Michael; Mirza, Osman
2018-01-08
The human proton coupled folic acid transporter PCFT is the major import route for dietary folates. Mutations in the gene encoding PCFT cause hereditary folic acid malabsorption, which manifests itself by compromised folate absorption from the intestine and also in impaired folate transport into the central nervous system. Since its recent discovery, PCFT has been the subject of numerous biochemical studies aiming at understanding its structure and mechanism. One major focus has been its oligomeric state, with some reports supporting oligomers and others a monomer. Here, we report the overexpression and purification of recombinant PCFT. Following detergent screening, n-Dodecyl β-D-maltoside (DDM) and lauryl maltose neopentyl glycol (LMNG) were chosen for further work as they exhibited the most optimal solubilization. We found that purified detergent solubilized PCFT was able to bind folic acid, thus indicating a functionally active protein. Size exclusion chromatography showed that PCFT in DDM was polydisperse; the LMNG preparation was clearly monodisperse but with shorter retention time than the major DDM peak. To assess the oligomeric state negative stain electron microscopy was performed which showed a particle with the size of a PCFT dimer. Copyright © 2017 Elsevier Inc. All rights reserved.
Lu, Chunliang; Su, Xiaoge; Floreancig, Paul E.
2013-01-01
Vinyl ethers can be protonated to generate oxocarbenium ions that react with Me3SiCN to form cyanohydrin alkyl ethers. Reactions that form racemic products proceed efficiently upon converting the vinyl ether to an α-chloro ether prior to cyanide addition in a pathway that proceeds through Brønsted acid-mediated chloride ionization. Enantiomerically enriched products can be accessed by directly protonating the vinyl ether with a chiral Brønsted acid to form a chiral ion pair. Me3SiCN acts as the nucleophile and PhOH serves as a stoichiometric proton source in a rare example of an asymmetric bimolecular nucleophilic addition reaction into an oxocarbenium ion. Computational studies provide a model for the interaction between the catalyst and the oxocarbenium ion. PMID:23968162
NASA Astrophysics Data System (ADS)
Semelsberger, Troy A.; Borup, Rodney L.
The production of a hydrogen-rich fuel-cell feed by dimethyl ether (DME) steam reforming was investigated using calculations of thermodynamic equilibrium as a function of steam-to-carbon ratio (0.00-4.00), temperature (100-600 °C), pressure (1-5 atm), and product species. Species considered were acetone, acetylene, carbon dioxide, carbon monoxide, dimethyl ether, ethane, ethanol, ethylene, formaldehyde, formic acid, hydrogen, isopropanol, methane, methanol, methyl-ethyl ether, n-propanol and water. Thermodynamic equilibrium calculations of DME steam reforming indicate complete conversion of dimethyl ether to hydrogen, carbon monoxide and carbon dioxide at temperatures greater than 200 °C and steam-to-carbon ratios greater than 1.25 at atmospheric pressure ( P = 1 atm). Increasing the operating pressure shifts the equilibrium toward the reactants; increasing the pressure from 1 to 5 atm decreases the conversion of dimethyl ether from 99.5 to 76.2%. The trend of thermodynamically stable products in decreasing mole fraction is methane, ethane, isopropyl alcohol, acetone, n-propanol, ethylene, ethanol, methyl-ethyl ether and methanol-formaldehyde, formic acid, and acetylene were not observed. Based on the equilibrium calculations, the optimal processing conditions for dimethyl ether steam reforming occur at a steam-to-carbon ratio of 1.50, a pressure of 1 atm, and a temperature of 200 °C. These thermodynamic equilibrium calculations show dimethyl ether processed with steam will produce hydrogen-rich fuel-cell feeds—with hydrogen concentrations exceeding 70%. The conversion of dimethyl ether via hydrolysis (considering methanol as the only product) is limited by thermodynamic equilibrium. Equilibrium conversion increases with temperature and steam-to-carbon ratio. A maximum dimethyl ether conversion of 62% is achieved at a steam-to-carbon ratio of 5.00 and a processing temperature of 600 °C.
Structure and Reactivity of Alkyl Ethers Adsorbed on CeO2(111) Model Catalysts
DOE Office of Scientific and Technical Information (OSTI.GOV)
F Calaza; T Chen; D Mullins
2011-12-31
The effect of surface hydroxyls on the adsorption of ether on ceria was explored. Adsorption of dimethyl ether (DME) and diethyl ether (DEE) on oxidized and reduced CeO{sub 2}(111) films was studied and compared with Ru(0001) using RAIRS and sXPS within a UHV environment. On Ru(0001) the ethers adsorb weakly with the molecular plane close to parallel to the surface plane. On the ceria films, the adsorption of the ethers was stronger than on the metal surface, presumably due to stronger interaction of the ether oxygen lone pair electrons with a cerium cation. This interaction causes the ethers to tiltmore » away from the surface plane compared to the Ru(0001) surface. No pronounced differences were found between oxidized (CeO{sub 2}) and reduced (CeOx) films. The adsorption of the ethers was found to be perturbed by the presence of OH groups on hydroxylated CeOx. In the case of DEE, the geometry of adsorption resembles that found on Ru, and in the case of dimethyl ether DME is in between that one found on clean CeOx and the metal surface. Decomposition of the DEE was observed on the OH/CeOx surface following high DEE exposure at 300 K and higher temperatures. Ethoxides and acetates were identified as adsorbed species on the surface by means of RAIRS and ethoxides and formates by s-XPS. No decomposition of dimethyl ether was observed on the OH/CeOx at these higher temperatures, implying that the dissociation of the C-O bond from ethers requires the presence of {beta}-hydrogen.« less
Structure and Reactivity of Alkyl Ethers Adsorbed on CeO(2)(111) Model Catalysts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Calaza, Florencia C; Chen, Tsung-Liang; Mullins, David R
2011-01-01
The effect of surface hydroxyls on the adsorption of ether on ceria was explored. Adsorption of dimethyl ether (DME) and diethyl ether (DEE) on oxidized and reduced CeO{sub 2}(111) films was studied and compared with Ru(0001) using RAIRS and sXPS within a UHV environment. On Ru(0001) the ethers adsorb weakly with the molecular plane close to parallel to the surface plane. On the ceria films, the adsorption of the ethers was stronger than on the metal surface, presumably due to stronger interaction of the ether oxygen lone pair electrons with a cerium cation. This interaction causes the ethers to tiltmore » away from the surface plane compared to the Ru(0001) surface. No pronounced differences were found between oxidized (CeO{sub 2}) and reduced (CeOx) films. The adsorption of the ethers was found to be perturbed by the presence of OH groups on hydroxylated CeOx. In the case of DEE, the geometry of adsorption resembles that found on Ru, and in the case of dimethyl ether DME is in between that one found on clean CeOx and the metal surface. Decomposition of the DEE was observed on the OH/CeOx surface following high DEE exposure at 300 K and higher temperatures. Ethoxides and acetates were identified as adsorbed species on the surface by means of RAIRS and ethoxides and formates by s-XPS. No decomposition of dimethyl ether was observed on the OH/CeOx at these higher temperatures, implying that the dissociation of the C-O bond from ethers requires the presence of {beta}-hydrogen.« less
Effect of p-amino-diphenyl ethers on hepatic microsomal cytochrome P450.
Jiang, Huidi; Xuan, Guida
2003-09-01
The present paper aims to investigate whether p-amino-2',4'-dichlorodiphenyl ether and p-amino-4'-methyldiphenyl ether are inhibitors as well as inducers of P450. Mice were given daily intraperitoneal (ip) injections of p-amino-2',4'-dichlorodiphenyl ether (0.25 mmol/kg) or p-amino-4'-methyldiphenyl ether (0.25 mmol/kg) for 4 days and tested at 24 h and 48 h after the last dose injection. The results showed the mice pentobarbital sleeping time was shorter and the P450 content of hepatic microsome increased significantly in the group pretreated with p-amino-4'-methyldiphenyl ether when compared with the control group, while in mice pretreated with p-amino-2',4'-dichlorodiphenyl ether the hepatic microsome P450 content increased but the pentobarbital sleeping time was extended in clear contrast to the control group. The sleeping time of the phenobarbital group (80 mg/kg daily ip injection for 4 days) was shortened at 24 h after the last injection with increased P450 content of hepatic microsome, but it showed no difference at 48 h. The zoxazolamine-paralysis times of mice treated with p-amino-2',4'-dichlorodiphenyl ether were longer than those of the control mice, while the same dose of zoxazolamine did not lead to paralysis in mice pretreated with BNF. p-Amino-2',4'-dichlorodiphenyl ether and p-amino-4'-methyldiphenyl ether inhibited the activity of 7-ethoxyresorufin O-deethylase from rat hepatic microsome induced by BNF in vitro by 70.0% and 50.1% respectively. These results suggest that p-amino-2',4'-dichlorodiphenyl ether and p-amino-4'-methyldiphenyl ether are inhibitors as well as inducers of P450.
Winters, C.E.
1957-11-12
A method for the preparation of a diethyl ether solution of uranyl nitrate is described. Previously the preparation of such ether solutions has been difficult and expensive, since crystalline uranyl nitrate hexahydrate dissolves very slowly in ether. An improved method for effecting such dissolution has been found, and it comprises adding molten uranyl nitrate hexahydrate at a temperature of 65 to 105 deg C to the ether while maintaining the temperature of the ether solvent below its boiling point.
Hintzenstern, U v; Schwarz, W
1996-02-01
The era of modern anaesthesia in Germany began on January 24th, 1847. This day, professor in ordinary Johann Ferdinand Heyfelder anaesthetized a patient with sulphuric ether in the clinic of surgery and ophthalmology of the University of Erlangen. By March 17th, 1847, Heyfelder had performed 121 surgical procedures under ether. The operations in majority were teeth-extractions, and a few more complex operations such as the treatment of a harelip or of lip cancer or the resection of the shoulder joint. Heyfelder described in detail 108 of these inhalations in a little book entitled The experiments with sulphuric ether. This monograph published in March, 1847, represents one of the first complete dissertations on sulphuric ether in the German literature. In a special chapter he analyzed the development of various physiological and psychological parameters during etherization. Heyfelder also examined blood and urine of some etherized patients and reported that he did not find any important or specific alterations. In 1847, Heyfelder was probably the first to apply salt-ether in man. After 4 administrations he concluded that salt ether acted more quickly but shorter than sulphuric ether. Advantageous were its application without problems and ease of induction. Disadvantageous were its high volatility, its price and the difficulty of getting it in a pure form. From December, 1847, on Heyfelder started to use chloroform. He was now able to perform more major operations, for example, the total resection of the hip-joint. In his book The experiments with sulphuric ether, salt ether, and chloroform he describes a great number of anaesthetic administrations using these 3 agents. In his summary Heyfelder concluded, that chloroform was undoubtly superior to sulphuric ether mainly because it was a quicker acting and longer lasting agent and leads to deeper narcosis. Moreover its application was much easier for it needed no special apparatus. However, because of its great anaesthetic potency, Heyfelder particularly demanded great caution in the application of chloroform. Explicitely he expected an assistant for chloroformizations, whose only duty was to supervise the inhalations and the patient--a forerunner of the modern specialized anaesthesiologist.
Lanigan, R S
2001-01-01
The Polypropylene Glycol (PPG) Butyl Ethers function as skinand hair-conditioning agents in cosmetics. Intestinal absorption of the PPG Butyl Ethers was inversely proportional to the molecular weight. In general, the toxicity of the PPG Butyl Ethers decreased as the molecular weight increased. In acute studies, moderate intraperitoneal (IP) doses of various PPG Butyl Ethers caused convulsive seizures in mice and anesthetized dogs, and large oral doses caused decreased activity, anuria, renal tubular swelling and necrosis, and hepatic swelling and necrosis. PPG-2 Butyl Ether vapors were nontoxic by the inhalation route. PPG-2 Butyl Ether was nontoxic in short-term feeding and dermal exposure studies in rats. In animal irritation studies, PPG-2 Butyl Ether caused minor, transient erythema and desquamation; in addition, erythema, edema, ecchymosis, necrosis, and other changes were observed during an acute percutaneous study. PPG-2 Butyl Ether also caused minor to moderate conjunctival irritation and minor corneal injury. PPG-2 Butyl Ether when dermally applied was nontoxic to pregnant rats and was nonteratogenic at doses up to 1.0 ml/kg/day. PPG BE800 at concentrations of 0.001% to 0.26% in feed was noncarcinogenic to rats after 2 years of treatment. In clinical studies, PPG BE800 was nonirritating and nonsensitizing to the skin when tested using 200 subjects. PPG-40 Butyl Ether was neither an irritant nor a sensitizer in a repeat-insult patch test using 112 subjects. Although clinical testing did not indicate significant skin irritation is produced by these ingredients, the animal test data did indicate the potential that these ingredients can be irritating. Therefore, it was concluded that the PPG Butyl Ethers can be used safely in cosmetic products if they are formulated to avoid irritation. Data on the component ingredients, Propylene Glycol, PPG, and n-Butyl Alcohol, from previous cosmetic ingredient safety assessments were also considered and found to support the safety of PPG Butyl Ethers.
Simultaneous determination of three surfactants and water in shampoo and liquid soap by ATR-FTIR.
Carolei, Luciano; Gutz, Ivano G R
2005-03-31
It is demonstrated for the first time that the principal constituents of a shampoo as well as of a liquid soap -three surfactants and water- can be determined directly, simultaneously and quickly in undiluted samples by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy in the middle infrared region, despite the broad absorption bands of the solvent. Two of the surfactants, sodium lauryl ether sulfate (SLES) and cocoamidopropyl betaine (CAPB), are common to both formulations; alkylpolyglucoside (APG) is the third surfactant of the liquid soap and cocodiethanolamide (CDEA), the corresponding ingredient of the shampoo. Absorbance data of the undiluted samples and of the calibration standards was collected in the middle infrared region of the spectrum (800-1600 and 1900-3000cm(-1)). Two methods of multivariate quantification were compared: classical least squares (CLS), where absorbance data measured at 200 wavenumbers was processed, and inverse least squares (ILS), where data at 10 selected wavenumbers was analyzed. A spectra normalization procedure, based on a dominating water band, was examined. Twenty-seven standard mixtures were used for each application, consisting of all combinations at three concentration levels of each surfactant, respectively the lower limit, the expected value and the upper limit accepted in quality control. By favoring wavenumbers where absorption bands of the minor components (APG in the liquid soap and CDEA in the shampoo) are more intense, good results were obtained for 18 simulated samples of shampoo and 18 samples of liquid soap, no matter if calculations were made by CLS or ILS. The relative errors for water (major component, 84-88%) and SLES (7-10%) were always below 2%; for CAPB (2-4%), APG (<2%) and CDEA (<2%), they occasionally reached 5% of the component, an uncertainty of less than 0.07% in terms of the sample weight.
Garcia, L S; Shimizu, R
1981-01-01
One hundred fecal specimens preserved in polyvinyl alcohol fixative were examined by the Formalin-ether sedimentation technique with ethyl acetate substituted for diethyl ether. Technical performance of the procedures, appearance and amount of sediment obtained, and organism morphology were comparable. Also, ethyl acetate is less flammable and, therefore, less dangerous to use than diethyl ether. Results of parasite recovery when diethyl ether or ethyl acetate was used revealed few clinical relevant differences, most of which could also have been attributed to other variables inherent in this type of diagnostic testing. PMID:7229014
Propenyl ether monomers for photopolymerization
Crivello, J.V.
1996-10-22
Propenyl ether monomers of formula A(OCH{double_bond}CHCH{sub 3}){sub n} wherein n is an integer from one to six and A is selected from cyclic ethers, polyether and alkanes are disclosed. The monomers are readily polymerized in the presence of cationic photoinitiators, when exposed to actinic radiation, to form poly(propenyl ethers) that are useful for coatings, sealants, varnishes and adhesives. Compositions for preparing polymeric coatings comprising the compounds of the above formula together with particular cationic photoinitiators are also disclosed, as are processes for making the monomers from allyl halides and readily available alcohols. The process involves rearranging the resulting allyl ethers to propenyl ethers.
Propenyl ether monomers for photopolymerization
Crivello, James V.
1996-01-01
Propenyl ether monomers of formula V A(OCH.dbd.CHCH.sub.3).sub.n wherein n is an integer from one to six and A is selected from cyclic ethers, polyether and alkanes are disclosed. The monomers are readily polymerized in the presence of cationic photoinitiators, when exposed to actinic radiation, to form poly(propenyl ethers) that are useful for coatings, sealants, varnishes and adhesives. Compositions for preparing polymeric coatings comprising the compounds of formula V together with particular cationic photoinitiators are also disclosed, as are processes for making the monomers from allyl halides and readily available alcohols. The process involves rearranging the resulting allyl ethers to propenyl ethers.
Process for making propenyl ethers and photopolymerizable compositions containing them
Crivello, James V.
1996-01-01
Propenyl ether monomers of formula V A(OCH.dbd.CHCH.sub.3).sub.n wherein n is an integer from one to six and A is selected from cyclic ethers, polyether and alkanes are disclosed. The monomers are readily polymerized in the presence of cationic photoinitiators, when exposed to actinic radiation, to form poly(propenyl ethers) that are useful for coatings, sealants, varnishes and adhesives. Compositions for preparing polymeric coatings comprising the compounds of formula V together with particular cationic photoinitiators are also disclosed, as are processes for making the monomers from allyl halides and readily available alcohols. The process involves rearranging the resulting allyl ethers to propenyl ethers.
Mechanisms of selective cleavage of C–O bonds in di-aryl ethers in aqueous phase
DOE Office of Scientific and Technical Information (OSTI.GOV)
He, Jiayue; Zhao, Chen; Mei, Donghai
2014-01-01
A novel route for cleaving the C-O aryl ether bonds of p-substituted H-, CH 3-, and OH- diphenyl ethers has been explored over Ni/SiO 2 catalysts at very mild conditions. The C-O bond of diphenyl ether is cleaved by parallel hydrogenolysis and hydrolysis (hydrogenolysis combined with HO* addition) on Ni. The rates as a function of H 2 pressure from 0 to 10 MPa indicate that the rate-determining step is the C-O bond cleavage on Ni. H* atoms compete with the organic reactant for adsorption leading to a maximum in the rate with increasing H 2 pressure. In contrast tomore » diphenyl ether, hydrogenolysis is the exclusive route for cleaving an ether C-O bond of di-p-tolyl ether to form p-cresol and toluene. 4,4'-dihydroxydiphenyl ether undergoes sequential surface hydrogenolysis, first to phenol and HOC 6H 4O* (adsorbed), which is then cleaved to phenol (C 6H 5O* with added H*) and H 2O (O* with two added H*) in a second step. Density function theory supports the operation of this pathway. Notably, addition of H* to HOC 6H 4O* is less favorable than a further hydrogenolytic C-O bond cleavage. The TOFs of three aryl ethers with Ni/SiO 2 in water followed the order 4,4'-dihydroxydiphenyl ether (69 h -1) > diphenyl ether (26 h -1) > di-p-tolyl ether (1.3 h -1), in line with the increasing apparent activation energies, ranging from 93 kJ∙mol -1 (4,4'-dihydroxydiphenyl ether) < diphenyl ether (98 kJ∙mol -1) to di-p-tolyl ether (105 kJ∙mol -1). D.M. thanks the support from the US Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle. Computing time was granted by the grand challenge of computational catalysis of the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL) and by the National Energy Research Scientific Computing Center (NERSC). EMSL is a national scientific user facility located at Pacific Northwest National Laboratory (PNNL) and sponsored by DOE’s Office of Biological and Environmental Research.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meznarich, Norman A.K.; Juggernauth, K Anne; Batzli, Kiersten M
2011-11-17
Aqueous solutions of polyoxyethylene-polyoxypropylene-polyoxyethylene (PEO-PPO-PEO) triblock copolymers (commercially available as Pluronic surfactants) micellize and structurally arrange into cubic quasicrystalline lattices as their temperature is raised. This structural evolution is seen macroscopically as a gelation, and the presence of these ordered phases can be controlled through both polymer concentration and temperature. The presence of added solutes within the dispersions can also affect the onset and kinetics of structure formation. Here we investigate the structures formed in Pluronic F127 solutions ranging from 20 to 30% with two pharmaceutical additives [methylparaben (MP) and dexamethasone (DX)] using small-angle X-ray scattering (SAXS). We observe bothmore » the progressive evolution and breakdown of these structures as the temperature is increased from 0 to 80 °C. Additionally, we conducted time-resolved SAXS measurements to elucidate the kinetics of the structural evolution. On the basis of the evolution of scattering peaks as the samples were being heated, we suggest that added MP changes the nucleation behavior of fcc phases within the sample from a heterogeneous process to a more homogeneous distribution of nucleated species. MP and DX also stabilize the micelle lattices, allowing them to persevere at higher temperatures. We observed the unusual result that the presence of DX caused the primary peaks of the structure factor to be suppressed, while preserving the higher order peaks. The primary peaks reappeared at the highest temperatures tested.« less
Nozawa, Kenji; Iwao, Yasunori; Noguchi, Shuji; Itai, Shigeru
2015-11-10
To generate products containing a stable form of clarithromycin (CAM) (form II) regardless of the initial crystal form of CAM or type of granulation solvent, the effects of five surfactants, or a water-soluble polymer (macrogol 400) were determined on the crystal transition of CAM. The metastable form (form I) was kneaded with water, after adding surfactants, or a water-soluble polymer. Form II was also kneaded with ethanol, after adding the same additives. The resulting samples were analyzed by powder X-ray diffraction. Form I was completely converted to form II by a wet granulation using water with additives bearing polyoxyethylene chains such as polysorbate 80 (PS80), polyoxyl 40 stearate or macrogol 400. The granulation of the form II using ethanol with these additives did not result in a crystal transition to form I. Furthermore, CAM tablets were manufactured using granules with PS80, and these crystal forms and dissolution behaviors were investigated. As a result, the wet granulation of CAM with PS80 gave CAM tablets containing only form II and PS80 did not have any adverse effects on tablet characteristics. Therefore, these data suggests that the crystal form of CAM can be controlled to be form II using a wet granulation process with additives bearing polyoxyethylene chains regardless of the initial crystal form of CAM or type of granulation solvent. Copyright © 2015 Elsevier B.V. All rights reserved.
40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).
Code of Federal Regulations, 2010 CFR
2010-07-01
... diglycidyl ether polymer (generic). 721.10017 Section 721.10017 Protection of Environment ENVIRONMENTAL... ether polymer (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified generically as amine terminated bisphenol A diglycidyl ether polymer (PMNs P...
40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Disubstituted benzene ether, polymer... Significant New Uses for Specific Chemical Substances § 721.1580 Disubstituted benzene ether, polymer with... chemical substance generically identified as disubstituted benzene ether, polymer with substituted phenol...
40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).
Code of Federal Regulations, 2011 CFR
2011-07-01
... diglycidyl ether polymer (generic). 721.10017 Section 721.10017 Protection of Environment ENVIRONMENTAL... ether polymer (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified generically as amine terminated bisphenol A diglycidyl ether polymer (PMNs P...
40 CFR 721.3438 - Chlorohydroxyalkyl butyl ether (generic).
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Chlorohydroxyalkyl butyl ether... Specific Chemical Substances § 721.3438 Chlorohydroxyalkyl butyl ether (generic). (a) Chemical substance... chlorohydroxyalkyl butyl ether (PMN P-99-1295) is subject to reporting under this section for the significant new use...
40 CFR 721.3438 - Chlorohydroxyalkyl butyl ether (generic).
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Chlorohydroxyalkyl butyl ether... Specific Chemical Substances § 721.3438 Chlorohydroxyalkyl butyl ether (generic). (a) Chemical substance... chlorohydroxyalkyl butyl ether (PMN P-99-1295) is subject to reporting under this section for the significant new use...
40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).
Code of Federal Regulations, 2013 CFR
2013-07-01
... diglycidyl ether polymer (generic). 721.10017 Section 721.10017 Protection of Environment ENVIRONMENTAL... ether polymer (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified generically as amine terminated bisphenol A diglycidyl ether polymer (PMNs P...
40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).
Code of Federal Regulations, 2014 CFR
2014-07-01
... diglycidyl ether polymer (generic). 721.10017 Section 721.10017 Protection of Environment ENVIRONMENTAL... ether polymer (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified generically as amine terminated bisphenol A diglycidyl ether polymer (PMNs P...
40 CFR 721.10017 - Amine terminated bisphenol A diglycidyl ether polymer (generic).
Code of Federal Regulations, 2012 CFR
2012-07-01
... diglycidyl ether polymer (generic). 721.10017 Section 721.10017 Protection of Environment ENVIRONMENTAL... ether polymer (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified generically as amine terminated bisphenol A diglycidyl ether polymer (PMNs P...
40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Disubstituted benzene ether, polymer... Significant New Uses for Specific Chemical Substances § 721.1580 Disubstituted benzene ether, polymer with... chemical substance generically identified as disubstituted benzene ether, polymer with substituted phenol...
40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Disubstituted benzene ether, polymer... Significant New Uses for Specific Chemical Substances § 721.1580 Disubstituted benzene ether, polymer with... chemical substance generically identified as disubstituted benzene ether, polymer with substituted phenol...
40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Disubstituted benzene ether, polymer... Significant New Uses for Specific Chemical Substances § 721.1580 Disubstituted benzene ether, polymer with... chemical substance generically identified as disubstituted benzene ether, polymer with substituted phenol...
40 CFR 721.1580 - Disubstituted benzene ether, polymer with substituted phenol (generic).
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Disubstituted benzene ether, polymer... Significant New Uses for Specific Chemical Substances § 721.1580 Disubstituted benzene ether, polymer with... chemical substance generically identified as disubstituted benzene ether, polymer with substituted phenol...
Huang, Kun; Ortiz-Marciales, Margarita; Correa, Wildeliz; Pomales, Edgardo; López, Xaira Y.
2009-01-01
Borane-mediated reduction of aryl and alkyl ketones with α-aryl- and α-pyridyloxy groups affords β-hydroxy ethers in high enantiomeric purity (up to 99% ee) and in good yield, using as catalyst 10 mol % of spiroborate ester 1 derived from (S)-diphenylprolinol. Representative β-hydroxy ethers are successfully converted to β-amino ethers, with minor epimerization, by phthalimide substitution under Mitsunobu’s conditions followed by hydrazinolysis, to obtain primary amino ethers or by imide reduction with borane to afford β-2,3-dihydro-1H-isoindol ethers. Non-racemic Mexiletine and nAChR analogues with potential biological activity are also synthesized in excellent yield by mesylation of key β-hydroxy pyridylethers and substitution with 5, 6 and 7 member ring heterocyclic amines. PMID:19413288
Alternative Fuels Data Center: Dimethyl Ether
Hydrocarbon Biofuels Dimethyl Ether Dimethyl ether (DME) is a synthetically produced alternative to diesel for use in specially designed compression ignition diesel engines. Under normal atmospheric conditions ether has several fuel properties that make it attractive for use in diesel engines. It has a very high
Zhu, Yuanqin; Zieren, Shelley; Manthiram, Arumugam
2011-07-14
Novel covalently crosslinked membranes based on sulfonated poly(ether ether ketone) and carboxylated polysulfone exhibit much lower methanol crossover and better performance in direct methanol fuel cells at 65 °C in 1 and 2 M methanol solutions compared to Nafion 115 membranes.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ether hook. 868.5420 Section 868.5420 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5420 Ether hook. (a) Identification. An ether hook is a device...
Takahashi, T; Iwasaki, K; Malchesky, P S; Harasaki, H; Matsushita, M; Nosé, Y; Rolin, H; Hall, P M
1993-03-01
Pyridoxalated-hemoglobin-polyoxyethylene conjugate (PHP), which is made from out-dated human red blood cells by two major chemical modifications, namely pyridoxalation and conjugation with polyoxyethylene (POE), is currently under development as a physiological oxygen carrier. This study assessed the effects of PHP-88 solution, which contains 8% (wt/vol) each of hemoglobin (Hb) and maltose, on renal function when it was infused 3 times every other day into the intact circulation of 8 dogs (5 dogs for the PHP group and 3 for the control group; 20 ml/kg for the first infusion, and 10 ml/kg each for the second and third infusions, at the rate of 2.5 ml/h/kg). Serial determinations of glomerular filtration rate (GFR) and renal plasma flow (RPF) were carried out pre- and postinfusion for up to 3 months along with measurements of blood and urine analyses, urine output rate, fractional excretion of sodium (FES), and free water clearance (CH2O). The results showed that plasma colloid osmotic pressure (COP) elevated an average of 3.3 mm Hg (p = 0.0085), and GFR and RPF tended to increase by 13% (NS) and 38% (NS), respectively, immediately after the third infusion with PHP solution. Urine output rate increased during and after the infusion, and FES and CH2O also increased for 24 h after the infusion in both groups. Blood urea nitrogen, serum creatinine, and serum Na+ concentrations were not affected greatly by the infusions, but hematocrit was decreased by 8% in the PHP group, indicating approximately a 42% expansion of plasma volume. These changes were observed to return to their preinfusion levels by 1 week postinfusion. Renal histology of the PHP group obtained at 2 weeks postinfusion revealed vacuole formation in the proximal tubules which was not associated with any pathologic changes indicative of cell death or regeneration. In 4 out of 5 dogs at 3 months postinfusion (necropsy), the vacuoles were not present. Though urinary N-acetyl-beta-glucosaminidase (NAG) activity had significantly increased after infusion, it returned to the preinfusion level by 1 month postinfusion. No detrimental effect of vacuoles on the assessed renal tubular functions was confirmed in the present study. The results demonstrated that multiple infusions of PHP solutions were well tolerated in normal dogs, and the observed effects were conceived predominantly attributable to the physiological response of the kidneys to an oncotic load into the circulation, which produced plasma volume expansion.
NASA Technical Reports Server (NTRS)
Jones, W. R., Jr.; Snyder, C. E., Jr.
1979-01-01
Boundary lubricating characteristics, thermal stability and oxidation-corrosion stability were determined for a fluorinated polyether and a perfluoropolyether triazine. A ball-on-disk apparatus, a tensimeter and oxidation-corrosion apparatus were used. Results were compared to data for a polyphenyl ether and a C-ether. The polyether and triazine yielded better boundary lubricating characteristics than either the polyphenyl ether or C-ether. The polyphenyl ether had the greatest thermal stability (443 C) while the other fluids had stabilities in the range 389 to 397 C. Oxidation-corrosion results indicated the following order of stabilities: perfluoropolyether triazine greater than polyphenylether greater than C-ether greater than fluorinated polyether.
Process for making propenyl ethers and photopolymerizable compositions containing them
Crivello, J.V.
1996-01-23
Propenyl ether monomers of formula A(OCH{double_bond}CHCH{sub 3}){sub n} (V) wherein n is an integer from one to six and A is selected from cyclic ethers, polyether, and alkanes are disclosed. The monomers are readily polymerized in the presence of cationic photoinitiators, when exposed to actinic radiation, to form poly(propenyl ethers) that are useful for coatings, sealants, varnishes and adhesives. Compositions for preparing polymeric coatings comprising the compounds of formula V together with particular cationic photoinitiators are also disclosed, as are processes for making the monomers from allyl halides and readily available alcohols. The process involves rearranging the resulting allyl ethers to propenyl ethers.
1985-03-01
used to remove trichloroethylene (TCE) from contaminated well water. 7 MATERIALS Chemicals: Trichloroethylene (Aldrich chemical, Milwaukee, WI), sodium ...Cleveland, OH), sodium hydrcxide (J.T. Baker, Phillipsburg, NJ), potassium dichloroisocyanurate (Dorex Inc., Frankfort, IL), potassium iodide starch...NJ). Media and Reagents: Plate count agar (Difco Laboratories, Detroit, MI), lauryl tryptose broth (Difco Laboratories, Detroit, MI), motility medium
Wu, Ben-Zen; Sun, Yu-Jie; Chen, Yan-Hua; Yak, Hwa Kwang; Yu, Jya-Jyun; Liao, Weisheng; Chiu, KongHwa; Peng, Shie-Ming
2016-08-01
Al-powder-supported Pd, Rh, and Rh-Pd catalysts were synthesized through a spontaneous redox reaction in aqueous solutions. These catalysts hydrodebrominated 4- and 4,4'-bromodiphenyl ethers in supercritical carbon dioxide at 200 atm CO2 containing 10 atm H2 and 80 °C in 1 h. Diphenyl ether was the major product of Pd/Al. Rh/Al and Rh-Pd/Al further hydrogenated two benzene rings of diphenyl ether to form dicyclohexyl ether. The hydrogenolysis of CO bonds on diphenyl ether over Rh/Al and Rh-Pd/Al was observed to generate cyclohexanol and cyclohexane (<1%). With respect to hydrodebromination efficiency and catalyst stability, Rh-Pd/Al among three catalysts is suggested to be used for ex situ degradation of polybrominated diphenyl ethers in supercritical carbon dioxide. Copyright © 2016 Elsevier Ltd. All rights reserved.
Sivaramakrishna, D; Swamy, Musti J
2015-09-08
A homologous series of l-alanine alkyl ester hydrochlorides (AEs) bearing 9-18 C atoms in the alkyl chain have been synthesized and characterized with respect to self-assembly, supramolecular structure, and phase transitions. The CMCs of AEs bearing 11-18 C atoms were found to range between 0.1 and 10 mM. Differential scanning calorimetric (DSC) studies showed that the transition temperatures (Tt), enthalpies (ΔHt) and entropies (ΔSt) of AEs in the dry state exhibit odd-even alternation, with the odd-chain-length compounds having higher Tt values, but the even-chain-length homologues showing higher values of ΔHt and ΔSt. In DSC measurements on hydrated samples, carried out at pH 5.0 and pH 10.0 (where they exist in cationic and neutral forms, respectively), compounds with 13-18 C atoms in the alkyl chain showed sharp gel-to-liquid crystalline phase transitions, and odd-even alternation was not seen in the thermodynamic parameters. The molecular structure, packing properties, and intermolecular interactions of AEs with 9 and 10 C atoms in the alkyl chain were determined by single crystal X-ray diffraction, which showed that the alkyl chains are packed in a tilted interdigitated bilayer format. d-Spacings obtained from powder X-ray diffraction studies exhibited a linear dependence on the alkyl chain length, suggesting that the other AEs also adopt an interdigitated bilayer structure. Turbidimetric, fluorescence spectroscopic, and isothermal titration calorimetric (ITC) studies established that in aqueous dispersions l-alanine lauryl ester hydrochloride (ALE·HCl) and sodium dodecyl sulfate (SDS) form an equimolar complex. Transmission electron microscopic and DSC studies indicate that the complex exists as unilamellar liposomes, which exhibit a sharp phase transition at ∼39 °C. The aggregates were disrupted at high pH, suggesting that the catanionic complex would be useful to develop a base-labile drug delivery system. ITC studies indicated that ALE·HCl forms a strong complex with DNA, suggesting that the AEs may find use in DNA therapeutics as well.
Polybrominated diphenyl ethers (PBDE) are a family of lipophilic brominated flame-retardants consisting of 209 possible congeners. Three PBDE commercially-produced mixtures are decabrominated diphenyl ether (e.g. deca-BDE or DE-83R); octabrominated diphenyl ether (e.g. octa-BDE o...
Code of Federal Regulations, 2014 CFR
2014-07-01
...., -monoalkyl ethers-.omega.-mono (hydrogen maleate)- (generic). 721.10398 Section 721.10398 Protection of...-ethanediyl),. alpha., -monoalkyl ethers-.omega.-mono (hydrogen maleate)- (generic). (a) Chemical substance... poly(oxy-1,2-ethanediyl), .alpha., -monoalkyl ethers-.omega.-mono (hydrogen maleate)- (PMN P-10-495) is...
Code of Federal Regulations, 2013 CFR
2013-07-01
...., -monoalkyl ethers-.omega.-mono (hydrogen maleate)- (generic). 721.10398 Section 721.10398 Protection of...-ethanediyl),. alpha., -monoalkyl ethers-.omega.-mono (hydrogen maleate)- (generic). (a) Chemical substance... poly(oxy-1,2-ethanediyl), .alpha., -monoalkyl ethers-.omega.-mono (hydrogen maleate)- (PMN P-10-495) is...
Code of Federal Regulations, 2012 CFR
2012-07-01
...., -monoalkyl ethers-.omega.-mono (hydrogen maleate)- (generic). 721.10398 Section 721.10398 Protection of...-ethanediyl),. alpha., -monoalkyl ethers-.omega.-mono (hydrogen maleate)- (generic). (a) Chemical substance... poly(oxy-1,2-ethanediyl), .alpha., -monoalkyl ethers-.omega.-mono (hydrogen maleate)- (PMN P-10-495) is...
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...
Furfuryl ethyl ether: important aging flavor and a new marker for the storage conditions of beer.
Vanderhaegen, Bart; Neven, Hedwig; Daenen, Luk; Verstrepen, Kevin J; Verachtert, Hubert; Derdelinckx, Guy
2004-03-24
Recently, it was reported that furfuryl ethyl ether is an important flavor compound indicative of beer storage and aging conditions. A study of the reaction mechanism indicates that furfuryl ethyl ether is most likely formed by protonation of furfuryl alcohol or furfuryl acetate followed by S(N)2-substitution of the leaving group by the nucleophilic ethanol. For the reaction in beer, a pseudo-first-order reaction kinetics was derived. A close correlation was found between the values predicted by the kinetic model and the actual furfuryl ethyl ether concentration evolution during storage of beer. Furthermore, 10 commercial beers of different types, aged during 4 years in natural conditions, were analyzed, and it was found that the furfuryl ethyl ether flavor threshold was largely exceeded in each type of beer. In these natural aging conditions, lower pH, darker color, and higher alcohol content were factors that enhanced furfuryl ethyl ether formation. On the other hand, sulfite clearly reduced furfuryl ethyl ether formation. All results show that the furfuryl ethyl ether concentration is an excellent time-temperature integrator for beer storage.
Guo, Junjie; Lee, Jaekwang; Contescu, Cristian I.; ...
2014-11-13
Crown ethers, introduced by Pedersen1, are at their most basic level neutral rings constructed of oxygen atoms linked by two- or three-carbon chains. They have attracted special attention for their ability to selectively incorporate various atoms2 or molecules within the cavity formed by the ring3-6. This property has led to the use of crown ethers and their compounds in a wide range of chemical and biological applications7,8. However, crown ethers are typically highly flexible, frustrating efforts to rigidify them for many uses that demand higher binding affinity and selectivity9,10. In this Letter, we report atomic-resolution images of the same basicmore » structures of the original crown ethers embedded in graphene. This arrangement constrains the crown ethers to be rigid and planar and thus uniquely suited for the many applications that crown ethers are known for. First-principles calculations show that the close similarity of the structures seen in graphene with those of crown ether molecules also extends to their selectivity towards specific metal cations depending on the ring size. Atoms (or molecules) incorporated within the crown ethers in graphene offer a simple environment that can be easily and systematically probed and modeled. Thus, we expect that this discovery will introduce a new wave of investigations and applications of chemically functionalized graphene.« less
Hepatic microsomal metabolism of BDE-47 and BDE-99 by lesser snow geese and Japanese quail.
Krieger, Lisa K; Szeitz, András; Bandiera, Stelvio M
2017-09-01
In the present study, we investigated the oxidative biotransformation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and 2,2',4,4',5-pentabromodiphenyl ether (BDE-99) by liver microsomes from wild lesser snow geese (Chen caerulescens caerulescens) and domesticated Japanese quail (Coturnix japonica). Formation of hydroxy-metabolites was analyzed using an ultra-high performance liquid chromatography-tandem mass spectrometry-based method. Incubation of BDE-47 with avian liver microsomes produced sixteen hydroxy-metabolites, eight of which were identified using authentic standards. The major metabolites formed by liver microsomes from individual lesser snow geese were 4-hydroxy-2,2',3,4'-tetrabromodiphenyl ether (4-OH-BDE-42), 3-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (3-OH-BDE-47), and 4'-hydroxy-2,2',4,5'-tetrabromodiphenyl ether (4'-OH-BDE-49). By comparison, 4-OH-BDE-42 and 4'-OH-BDE-49, but not 3-OH-BDE-47, were major metabolites of Japanese quail liver microsomes. Unidentified metabolites included monohydroxy- and dihydroxy-tetrabromodiphenyl ethers. Incubation of BDE-99 with avian liver microsomes produced seventeen hydroxy-metabolites, twelve of which were identified using authentic standards. The major metabolites formed by lesser snow goose liver microsomes were 2,4,5-tribromophenol, 3-OH-BDE-47, 4'-OH-BDE-49, 4-hydroxy-2,2',3,4',5-pentabromodiphenyl ether (4-OH-BDE-90), and 5'-hydroxy-2,2',4,4',5-pentabromodiphenyl ether (5'-OH-BDE-99). By comparison, the major metabolites produced by liver microsomes from Japanese quail included 6-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (6-OH-BDE-47) and 2-hydroxy-2',3,4,4',5-pentabromodiphenyl ether (2-OH-BDE-123), but not 3-OH-BDE-47. Unidentified metabolites consisted of monohydroxy-pentabromodiphenyl ethers, monohydroxy-tetrabromodiphenyl ethers and dihydroxy-tetrabromodiphenyl ethers. Another difference between the two species was that formation rates of BDE-47 and BDE-99 metabolites were greater with liver microsomes from male than female Japanese quail, but a sex difference was not observed with lesser snow geese. Copyright © 2017 Elsevier Ltd. All rights reserved.
Finishing Systems for Naval Aircraft Applications: Current Schemes and Future Trends
2000-01-01
glycidyl ether (CGE) and the difunctional neopentyl glycol , diglycidyl ether (NGDE) are pictured below in Figure 7. 16 o r CH3 OH CH2- XCH-CH2--0-<Q)-C...glycidyl ether (CGE) and neopentyl glycol , diglycidyl ether (NGDE). Coatings prepared with CGE were unacceptable due to poor surface properties and
Thermoset epoxy polymers from renewable resources
East, Anthony [Madison, NJ; Jaffe, Michael [Maplewood, NJ; Zhang, Yi [Harrison, NJ; Catalani, Luiz H [Carapicuiba, BR
2009-11-17
Novel thermoset epoxy polymers using the bisglycidyl ethers of anhydrosugars, such as isosorbide, isomannide, and isoidide, are disclosed. The bisglycidyl ethers are useful as substitutes for bisphenol A in the manufacture of thermoset epoxy ethers. The anhydrosugars are derived from renewable sources and the bisglycidyl ethers are not xenoestrogenic and the thermoset curing agents are likewise derived form renewable resources.
Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in furniture foam (pentaBDE), plastics for TV cabinets, consumer electronics, wire insulation, and backcoatings for draperies and upholstery (decaBDE), and plastics for personal computers and small appliances (oc...
Functionalized poly(arylene ethers) as toughness modifiers for bismaleimides
NASA Technical Reports Server (NTRS)
Stenzenberger, H. D.; Roemer, W.; Hergenrother, P. M.; Jensen, B.; Breitigam, W.
1990-01-01
A family of novel, low molecular weight functionalized poly(arylene ether) resins has been investigated to ascertain its members' toughness-imparting contribution to neat bismaleimide (BMI) resin and BMI-matrix laminate composite properties. Attention is given to the contribution of the reactive poly(arylene ether)'s backbone chemistry to fracture toughness, as well as to the comparative influence of high and low molecular weight reactive poly(arylene ether) types on the modified BMI resin systems. The modified BMIs possess a polyphase morphology, with good adhesion between the thermoplastic nodules and the host thermoset systems.
Dietz, Mark L.; Horwitz, E. Philip; Bartsch, Richard A.; Barrans, Jr., Richard E.; Rausch, David
1999-01-01
A crown ether cesium ion extractant is disclosed as is its synthesis. The crown ether cesium ion extractant is useful for the selective purification of cesium ions from aqueous acidic media, and more particularly useful for the isolation of radioactive cesium-137 from nuclear waste streams. Processes for isolating cesium ions from aqueous acidic media using the crown ether cesium extractant are disclosed as are processes for recycling the crown ether cesium extractant and processes for recovering cesium from a crown ether cesium extractant solution.
Dietz, M.L.; Horwitz, E.P.; Bartsch, R.A.; Barrans, R.E. Jr.; Rausch, D.
1999-03-30
A crown ether cesium ion extractant is disclosed as is its synthesis. The crown ether cesium ion extractant is useful for the selective purification of cesium ions from aqueous acidic media, and more particularly useful for the isolation of radioactive cesium-137 from nuclear waste streams. Processes for isolating cesium ions from aqueous acidic media using the crown ether cesium extractant are disclosed as are processes for recycling the crown ether cesium extractant and processes for recovering cesium from a crown ether cesium extractant solution. 4 figs.
Alkyl Aryl Ether Bond Formation with PhenoFluor**
Shen, Xiao; Neumann, Constanze N.; Kleinlein, Claudia; Claudia, Nathaniel W.; Ritter, Tobias
2015-01-01
An alkyl aryl ether bond formation reaction between phenols and primary and secondary alcohols with PhenoFluor has been developed. The reaction features a broad substrate scope and tolerates many functional groups, and substrates that are challenging for more conventional ether bond forming processes may be coupled. A preliminary mechanistic study indicates reactivity distinct from conventional ether bond formation. PMID:25800679
Aza crown ether compounds as anion receptors
Lee, Hung Sui; Yang, Xiao-Oing; McBreen, James
1998-08-04
A family of aza-ether based compounds including linear, multi-branched and aza-crown ethers is provided. When added to non-aqueous battery electrolytes, the new family of aza-ether based compounds acts as neutral receptors to complex the anion moiety of the electrolyte salt thereby increasing the conductivity and the transference number of LI.sup.+ ion in alkali metal batteries.
Poly(arylene ether)s That Resist Atomic Oxygen
NASA Technical Reports Server (NTRS)
Connell, John W.; Hergenrother, Paul; Smith, Joseph G., Jr.
1994-01-01
Novel poly(arylene ether)s containing phosphine oxide (PAEPO's) made via aromatic nucleophilic displacement reactions of activated aromatic dihalides (or, in some cases, activated aromatic dinitro compounds) with new bisphenol monomers containing phosphine oxide. Exhibited favorable combination of physical and mechanical properties and resistance to monatomic oxygen in oxygen plasma environment. Useful as adhesives, coatings, films, membranes, moldings, and composite matrices.
Aza crown ether compounds as anion receptors
Lee, H.S.; Yang, X.O.; McBreen, J.
1998-08-04
A family of aza-ether based compounds including linear, multi-branched and aza-crown ethers is provided. When added to non-aqueous battery electrolytes, the new family of aza-ether based compounds acts as neutral receptors to complex the anion moiety of the electrolyte salt thereby increasing the conductivity and the transference number of LI{sup +} ion in alkali metal batteries. 3 figs.
Safety Assessment of Alkyl PEG/PPG Ethers as Used in Cosmetics.
Fiume, Monice M; Heldreth, Bart; Bergfeld, Wilma F; Belsito, Donald V; Hill, Ronald A; Klaassen, Curtis D; Liebler, Daniel C; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Andersen, F Alan
2016-07-01
The Cosmetic Ingredient Review (CIR) Expert Panel assessed the safety of 131 alkyl polyethylene glycol (PEG)/polypropylene glycol ethers as used in cosmetics, concluding that these ingredients are safe in the present practices of use and concentration described in this safety assessment when formulated to be nonirritating. Most of the alkyl PEG/PPG ethers included in this review are reported to function in cosmetics as surfactants, skin-conditioning agents, and/or emulsifying agents. The alkyl PEG/PPG ethers share very similar physiochemical properties as the alkyl PEG ethers, which were reviewed previously by the CIR Expert Panel and found safe when formulated to be nonirritating. The alkyl PEG ethers differ by the inclusion of PPG repeat units, which are used to fine-tune the surfactant properties of this group. The Panel relied heavily on data on analogous ingredients, extracted from the alkyl PEG ethers and PPG reports, when making its determination of safety. © The Author(s) 2016.
Process for producing high purity isoolefins and dimers thereof by dissociation of ethers
Smith, L.A. Jr.; Jones, E.M. Jr.; Hearn, D.
1984-05-08
Alkyl tertiary butyl ether or alkyl tertiary amyl ether is dissociated by vapor phase contact with a cation acidic exchange resin at temperatures in the range of 150 to 250 F at LHSV of 0.1 to 20 to produce a stream consisting of unreacted ether, isobutene or isoamylene and an alcohol corresponding to the alkyl radical. After the alcohol is removed, the ether/isoolefin stream may be fractionated to obtain a high purity isoolefin (99+%) or the ether/isoolefin stream can be contacted in liquid phase with a cation acidic exchange resin to selectively dimerize the isoolefin in a highly exothermic reaction, followed by fractionation of the dimerization product to produce high purity diisoolefin (97+%). In the case where the alkyl is C[sub 3] to C[sub 6] and the corresponding alcohol is produced on dissociation of the ether, combined dissociation-distillation may be carried out such that isoolefin is the overhead product and alcohol the bottom. 2 figs.
Process for producing high purity isoolefins and dimers thereof by dissociation of ethers
Smith, Jr., Lawrence A.; Jones, Jr., Edward M.; Hearn, Dennis
1984-01-01
Alkyl tertiary butyl ether or alkyl tertiary amyl ether is dissociated by vapor phase contact with a cation acidic exchange resin at temperatures in the range of 150.degree. to 250.degree. F. at LHSV of 0.1 to 20 to produce a stream consisting of unreacted ether, isobutene or isoamylene and an alcohol corresponding to the alkyl radical. After the alcohol is removed, the ether/isoolefin stream may be fractionated to obtain a high purity isoolefin (99+%) or the ether/isoolefin stream can be contacted in liquid phase with a cation acidic exchange resin to selectively dimerize the isoolefin in a highly exothermic reaction, followed by fractionation of the dimerization product to produce high purity diisoolefin (97+%). In the case where the alkyl is C.sub.3 to C.sub.6 and the corresponding alcohol is produced on dissociation of the ether, combined dissociation-distillation may be carried out such that isoolefin is the overhead product and alcohol the bottom.
Simulating Bilayers of Nonionic Surfactants with the GROMOS-Compatible 2016H66 Force Field.
Senac, Caroline; Urbach, Wladimir; Kurtisovski, Erol; Hünenberger, Philippe H; Horta, Bruno A C; Taulier, Nicolas; Fuchs, Patrick F J
2017-10-03
Polyoxyethylene glycol alkyl ether amphiphiles (C i E j ) are important nonionic surfactants, often used for biophysical and membrane protein studies. In this work, we extensively test the GROMOS-compatible 2016H66 force field in molecular dynamics simulations involving the lamellar phase of a series of C i E j surfactants, namely C 12 E 2 , C 12 E 3 , C 12 E 4 , C 12 E 5 , and C 14 E 4 . The simulations reproduce qualitatively well the monitored structural properties and their experimental trends along the surfactant series, although some discrepancies remain, in particular in terms of the area per surfactant, the equilibrium phase of C 12 E 5 , and the order parameters of C 12 E 3 , C 12 E 4 , and C 12 E 5 . The polar head of the C i E j surfactants is highly hydrated, almost like a single polyethyleneoxide (PEO) molecule at full hydration, resulting in very compact conformations. Within the bilayer, all C i E j surfactants flip-flop spontaneously within tens of nanoseconds. Water-permeation is facilitated, and the bending rigidity is 4 to 5 times lower than that of typical phospholipid bilayers. In line with another recent theoretical study, the simulations show that the lamellar phase of C i E j contains large hydrophilic pores. These pores should be abundant in order to reproduce the comparatively low NMR order parameters. We show that their contour length is directly correlated to the order parameters, and we estimate that they should occupy approximately 7-10% of the total membrane area. Due to their highly dynamic nature (rapid flip-flops, high water permeability, observed pore formation), C i E j surfactant bilayers are found to represent surprisingly challenging systems in terms of modeling. Given this difficulty, the results presented here show that the 2016H66 parameters, optimized independently considering pure-liquid as well as polar and nonpolar solvation properties of small organic molecules, represent a good starting point for simulating these systems.
NASA Astrophysics Data System (ADS)
Zhang, Shuling; Wang, Hongsong; Wang, Guibin; Jiang, Zhenhua
2012-07-01
A material with high dielectric constant, low dielectric loss, and good mechanical and thermal properties was produced using multi-wall carbon nanotubes (MWCNTs) wrapped with poly(ether sulphone) (PES) dispersed in a poly(ether ether ketone) (PEEK) matrix. The material was fabricated using melt-blending, and MWCNT/PEEK composites show different degrees of improvement in the measured dielectric, mechanical, and thermal properties as compared to pure PEEK. This is attributed to the high conductivity of MWCNTs, the effect of wrapping MWCNTs with PES, the good dispersion of the wrapped MWCNTs in PEEK, and the strong interfacial adhesion between the wrapped MWCNTs and the PEEK.
Research in acetylene containing monomers
NASA Technical Reports Server (NTRS)
Ogliaruso, M. A.
1976-01-01
The preparation of precursor bisbenzils with pendant acetylene linkages for use in the synthesis of new aromatic poly (phenyl quinoxalines) was investigated. Attempts to condense para, para prime-dibromo benzil and potassium acetylide in liquid ammonia and in toluene, to prepare 4-phenyl acetyl phenyl ether, 4-(paraacetylphenyl) acetyl phenyl ether, 4-phenyl acetyl-4 primeacetyl phenyl acetyl phenyl ether, the reaction of 4-phenyl acetyl phenyl ether with Villsmeier reagent to prepare 4-(beta-chloro cinnamaldehyde) phenyl ether, the reaction of 4-(para-acetyl phenyl) acetyl phenyl ether with Villsmeier reagent, and the oxidation of bibenzil to prepare benzil are described. The reactions of phenyl acetylene with oxidizing agent, of phenyl acetylene with bromine, of 1,1,2,2-tetrabromo ethyl benzene with zinc and with oxidizing agent are described.
Divinyl ether synthase gene and protein, and uses thereof
Howe, Gregg A [East Lansing, MI; Itoh, Aya [Tsuruoka, JP
2011-09-13
The present invention relates to divinyl ether synthase genes, proteins, and methods of their use. The present invention encompasses both native and recombinant wild-type forms of the synthase, as well as mutants and variant forms, some of which possess altered characteristics relative to the wild-type synthase. The present invention also relates to methods of using divinyl ether synthase genes and proteins, including in their expression in transgenic organisms and in the production of divinyl ether fatty acids, and to methods of suing divinyl ether fatty acids, including in the protection of plants from pathogens.
Divinyl ether synthase gene, and protein and uses thereof
Howe, Gregg A.; Itoh, Aya
2006-12-26
The present invention relates to divinyl ether synthase genes, proteins, and methods of their use. The present invention encompasses both native and recombinant wild-type forms of the synthase, as well as mutants and variant forms, some of which possess altered characteristics relative to the wild-type synthase. The present invention also relates to methods of using divinyl ether synthase genes and proteins, including in their expression in transgenic organisms and in the production of divinyl ether fatty acids, and to methods of suing divinyl ether fatty acids, including in the protection of plants from pathogens.
Dave, Rutesh H; Patel, Hardikkumar H; Donahue, Edward; Patel, Ashwinkumar D
2013-10-01
The solubility of drugs remains one of the most challenging aspects of formulation development. There are numerous ways to improve the solubility of drugs amongst which the most promising strategy is solid dispersion. Different ratios of sulfathiazole: PVP-K29/32: sodium lauryl sulfate (SLS) were prepared (1:1:0.1, 1:1:0.5, 1:1:1) and various methods were employed to characterize the prepared solid dispersions, namely modulated differential scanning calorimeter, X-ray powder diffraction, Fourier Transformed Infrared Spectroscopy and dissolution studies. Lack of crystallinity was observed in internal and external systems suggesting a loss of crystallinity, whereas the physical mixtures showed a characteristic peak of sulfathiazole. In vitro dissolution results clearly showed that the incorporation of a relatively small amount of surfactants (5, 20 or 33% w/w) into a solid dispersion can improve its dissolution rates compared to binary solid dispersion (SD) alone and pure sulfathiazole. In all ratios solid dispersion internal shows a higher dissolution rate compared to a physical mixture and solid dispersion external which suggests that the way that the surfactant is incorporated into the solid dispersion plays an important role in changing the solubility of a drug. The solubilization mechanism is mainly responsible for this higher dissolution rate when we incorporate the SLS in SD.
Kwon, Jae-Sung; Kim, Kwang-Mahn; Kim, Kyoung-Nam
2014-10-01
The biocompatibility evaluation of nanomaterials is essential for their medical diagnostic and therapeutic usage, where a cytotoxicity test is the simplest form of biocompatibility evaluation. Three methods have been commonly used in previous studies for the cytotoxicity testing of nanomaterials: trypan blue exclusion, colorimetric assay using water soluble tetrazolium (WST), and imaging under a microscope following calcein AM/ethidium homodimer-1 staining. However, there has yet to be a study to compare each method. Therefore, in this study three methods were compared using the standard reference material of sodium lauryl sulfate (SLS). Each method of the cytotoxicity test was carried out using mouse fibroblasts of L-929 exposed to different concentrations of SLS. Compared to the gold standard trypan blue exclusion test, both colorimetric assay using water soluble tetrazolium (WST) and imaging under microscope with calcein AM/ethidium homodimer-1 staining showed results that were not statistically different. Also, each method exhibited various advantages and disadvantages, which included the need of equipment, time taken for the experiment, and provision of additional information such as cell morphology. Therefore, this study concludes that all three methods of cytotoxicity testing may be valid, though careful consideration will be needed when selecting tests with regard to time, finances, and the amount of information required by the researcher(s).
Clemmensen, Anders; Andersen, Klaus E; Clemmensen, Ole; Tan, Qihua; Petersen, Thomas K; Kruse, Torben A; Thomassen, Mads
2010-09-01
The pathogenesis of irritant contact dermatitis (ICD) is poorly understood, and genes participating in the epidermal response to chemical irritants are only partly known. It is commonly accepted that different irritants have different mechanisms of action in the development of ICD. To define the differential molecular events induced in the epidermis by different irritants, we collected sequential biopsies ((1/2), 4, and 24 hours after a single exposure and at day 11 after repeated exposure) from human volunteers exposed to either sodium lauryl sulfate (SLS) or nonanoic acid (NON). Gene expression analysis using high-density oligonucleotide microarrays (representing 47,000 transcripts) revealed essentially different pathway responses (1/2)hours after exposure: NON transiently induced the IL-6 pathway as well as a number of mitogen-activated signaling cascades including extracellular signal-regulated kinase and growth factor receptor signaling, whereas SLS transiently downregulated cellular energy metabolism pathways. Differential expression of the cyclooxygenase-2 and matrix metalloproteinase 3 transcripts was confirmed immunohistochemically. After cumulative exposure, 883 genes were differentially expressed, whereas we identified 23 suggested common biomarkers for ICD. In conclusion, we bring new insights into two hitherto less well-elucidated phases of skin irritancy: the very initial as well as the late phase after single and cumulative mild exposures, respectively.
Petersen, L J; Lyngholm, A M; Arendt-Nielsen, L
2010-09-01
Sodium lauryl sulfate (SLS) is a known irritant. It releases pro-inflammatory mediators considered pivotal in inflammatory pain. The sensory effects of SLS in the skin remain largely unexplored. In this study, SLS was evaluated for its effect on skin sensory functions. Eight healthy subjects were recruited for this study. Skin sites were randomized to topical SLS 0.25, 0.5, 1, 2% and vehicle for 24 h. Topical capsaicin 1% was applied for 30 min at 24 h after SLS application. Assessments included laser Doppler imaging of local vasodilation and flare reactions, rating of spontaneous pain, assessment of primary thermal and tactile hyperalgesia, and determination of secondary dynamic and static hyperalgesia. SLS induced significant and dose-dependent local inflammation and primary hyperalgesia to tactile and thermal stimulation at 24 h after application, with SLS 2% treatment eliciting results comparable to those observed following treatment with capsaicin 1%. SLS induced no spontaneous pain, small areas of flare, and minimal secondary hyperalgesia. The primary hyperalgesia vanished within 2-3 days, whereas the skin inflammation persisted and was only partly normalized by Day 6. SLS induces profound perturbations of skin sensory functions lasting 2-3 days. SLS-induced inflammation may be a useful model for studying the mechanisms of inflammatory pain.
Löffler, H; Happle, R
2003-01-01
The cutaneous reaction to detergents follows distinct kinetic rules: the duration of application and the irritant concentration are of major importance. The aim of this study was to evaluate the differences in kinetics of skin reaction between the standard irritant sodium lauryl sulfate (SLS), and 2 modern detergents: sodium laureth sulfate (SLES) and alkyl polyglucoside (APG). We performed patch testing with SLS and SLES (or APG) at different concentrations (0.125, 0.25, 0.5, 1.0 and 2.0%) and with different exposure times (6, 12 and 24 h). Evaluation was conducted by measurement of transepidermal water loss (TEWL) and laser Doppler flowmetry (LD) 24 h, 7 and 10 days after patch removal. We found a pronounced reaction to SLS, and a far milder one to SLES. Even at the highest concentration the skin reaction to APG was hard to detect. During the regeneration period (day 3-10) SLS showed even at day 10 an increased TEWL at all concentrations tested. The irritation due to SLES was convincingly detectable only up to day 7, whereas the APG-tested skin areas showed no significant reaction even at day 3. These results demonstrate the improvement in reduction of skin irritation achieved by development of novel detergents.
Stratum corneum cytokines and skin irritation response to sodium lauryl sulfate.
De Jongh, Cindy M; Verberk, Maarten M; Withagen, Carien E T; Jacobs, John J L; Rustemeyer, Thomas; Kezic, Sanja
2006-06-01
Little is known about cytokines involved in chronic irritant contact dermatitis. Individual cytokine profiles might explain at least part of the differences in the individual response to irritation. Our objective was to investigate the relation between baseline stratum corneum (SC) cytokine levels and the skin response to a single and a repeated irritation test. This study also aimed to determine changes in SC cytokine levels after repeated irritation. Transepidermal water loss (TEWL) and erythema were measured in 20 volunteers after single 24-hr exposure to 1% sodium lauryl sulfate (SLS), and during and after repeated exposure to 0.1% SLS over a 3-week period. SC cytokine levels were measured from an unexposed skin site and from the repeatedly exposed site. Interleukin (IL)-1alpha decreased by 30% after repeated exposure, while IL-1RA increased 10-fold and IL-8 increased fourfold. Baseline IL-1RA and IL-8 values were predictors of TEWL and erythema after single exposure (r = 0.55-0.61). 6 subjects showed barrier recovery during repeated exposure. Baseline IL-1RA and IL-8 levels are likely to be indicators of higher skin irritability after single exposure to SLS. Barrier repair in some of the subjects might explain the lack of agreement between the TEWL response after single and repeated irritation.
Qiang, Dongmei; Gunn, Jocelyn A; Schultz, Leon; Li, Z Jane
2010-12-01
The objective of this study was to investigate the effects of sodium lauryl sulfate (SLS) from different sources on solubilization/wetting, granulation process, and tablet dissolution of BILR 355 and the potential causes. The particle size distribution, morphology, and thermal behaviors of two pharmaceutical grades of SLS from Spectrum and Cognis were characterized. The surface tension and drug solubility in SLS solutions were measured. The BILR 355 tablets were prepared by a wet granulation process and the dissolution was evaluated. The critical micelle concentration was lower for Spectrum SLS, which resulted in a higher BILR 355 solubility. During wet granulation, less water was required to reach the same end point using Spectrum than Cognis SLS. In general, BILR 355 tablets prepared with Spectrum SLS showed a higher dissolution than the tablets containing Cognis SLS. Micronization of SLS achieved the same improved tablet dissolution as micronized active pharmaceutical ingredient. The observed differences in wetting and solubilization were likely due to the different impurity levels in SLS from two sources. This study demonstrated that SLS from different sources could have significant impact on wet granulation process and dissolution. Therefore, it is critical to evaluate SLS properties from different suppliers, and then identify optimal formulation and process parameters to ensure robustness of drug product manufacture process and performance.
Aljaberi, Ahmad; Chatterji, Ashish; Dong, Zedong; Shah, Navnit H; Malick, Waseem; Singhal, Dharmendra; Sandhu, Harpreet K
2013-01-01
To evaluate and optimize sodium lauryl sulfate (SLS) and magnesium stearate (Mg.St) levels, with respect to dissolution and compaction, in a high dose, poorly soluble drug tablet formulation. A model poorly soluble drug was formulated using high shear aqueous granulation. A D-optimal design was used to evaluate and model the effect of granulation conditions, size of milling screen, SLS and Mg.St levels on tablet compaction and ejection. The compaction profiles were generated using a Presster(©) compaction simulator. Dissolution of the kernels was performed using a USP dissolution apparatus II and intrinsic dissolution was determined using a stationary disk system. Unlike kernels dissolution which failed to discriminate between tablets prepared with various SLS contents, the intrinsic dissolution rate showed that a SLS level of 0.57% was sufficient to achieve the required release profile while having minimal effect on compaction. The formulation factors that affect tablet compaction and ejection were identified and satisfactorily modeled. The design space of best factor setting to achieve optimal compaction and ejection properties was successfully constructed by RSM analysis. A systematic study design helped identify the critical factors and provided means to optimize the functionality of key excipient to design robust drug product.
Casari, Alice; Farnetani, Francesca; De Pace, Barbara; Losi, Amanda; Pittet, Jean-Christophe; Pellacani, Giovanni; Longo, Caterina
2017-03-01
Irritant contact dermatitis is caused by skin barrier damage. Vitamin E is an antioxidant that is commonly used in cosmetics to prevent photo-damage. To show the usefulness of reflectance confocal microscopy in the assessment of irritant skin damage caused by sodium lauryl sulfate (SLS) and of the protective action of vitamin E applied prior to skin irritation. Ten healthy volunteers were enrolled. Irritation was induced by the application of a patch test containing SLS 5% aq. for 24 h. Three sites were compared: one site on which a product with vitamin E was applied before SLS treatment, one site on which the same product was applied after SLS treatment, and one control site (SLS only). Each site was evaluated with reflectance confocal microscopy, providing in vivo tissue images at nearly histological resolution. We also performed a computerized analysis of the VivaStack® images. Reflectance confocal microscopy is able to identify signs of skin irritation and the preventive effect of vitamin E application. Reflectance confocal microscopy is useful in the objective assessment of irritative skin damage. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Kuzmina, Natalia; Hagströmer, Lena; Nyrén, Miruna; Emtestam, Lennart
2003-11-01
Identification of subjects at risk for contact dermatitis by screening tests is desirable in order to adjust the preventive measures to individual skin susceptibility. The present study aimed to examine the effects of basic physiological features, such as baseline electrical impedance (IMP) and transepidermal water loss (TEWL), on reactivity to sodium lauryl sulphate (SLS). On the basis of two previous studies, we re-evaluated the experimental irritant skin reactions (50 microL of 2% SLS in large Finn Chambers for 24 h) on the volar forearms of 29 patients with eczema and 19 healthy controls. We found definite differences in the baseline values of IMP, between the patients and the controls. Moreover, patients with eczema showed higher TEWL and lower MIX values on day 3 after exposure to SLS, which may indicate differences in SLS reactivity. After the study, the biophysical parameters of the eczema patients did not return to baseline, which suggests that their skin heals more slowly than that of normal subjects. Our findings indicate that the IMP technique may help to 'detect' chemically vulnerable skin. However, more studies are needed to determine the value of the basal electrical impedance parameters in assessing the risk of developing irritant contact dermatitis.
Copoví, A; Díez-Sales, O; Herráez-Domínguez, J V; Herráez-Domínguez, M
2006-05-11
The percutaneous penetration-enhancing effects of glycolic acid, lactic acid and sodium lauryl sulphate through the human epidermis was investigated using 5-fluorouracil as a hydrophilic model permeant and three compounds belonging to the phenylalcohols: 2-phenyl-ethanol, 4-phenyl-butanol and 5-phenyl-pentanol. The lipophilicity values of the compounds ranged from log Poct -0.95 to 2.89. The effect of the enhancer concentration was also studied. Skin pretreatment with aqueous solutions of the three enhancers did not increase the permeability coefficient of the most lipophilic compound (log Poct = 2.89). For the other compounds assayed, the increase in the permeability coefficients depended on the concentration used in skin pretreatment, and on the lipophilicity of the compounds tested-and was always greater for the most hydrophilic compound (5-fluorouracil), for which lactic acid exerted a greater enhancer effect than glycolic acid or sodium lauryl sulphate. Primary irritation testing of the three enhancers was also carried out at the two concentrations used in skin pretreatment for diffusional experiments (1% and 5%, w/w). The least irritant capacity corresponded to lactic acid; consequently, this alpha-hydroxyacid could be proposed as a percutaneous penetration enhancer for hydrophilic molecules that are of interest for transdermal administration.
The influence of body mass index on skin susceptibility to sodium lauryl sulphate.
Löffler, H; Aramaki, J U N; Effendy, Isaak
2002-02-01
The influence of nutrition on the physiological functions of man is well studied. Numerous diseases can be exacerbated by obesity. However, it has not yet been determined whether body weight and body mass index (BMI), as an indicator of a high body fat store, can influence skin sensitivity. This study investigates the correlation between body mass index and the epidermal functions, evaluated by bioengineering methods, before and after an irritant patch test with sodium lauryl sulphate (SLS). Epidermal functions were evaluated using an evaporimeter, chromameter and laser-Doppler-flowmeter. Patch testing was conducted for 48 h with two different concentrations of SLS (0.25% and 0.5%) on the forearms of healthy volunteers. Measurements were performed 24h after patch removal. Obese individuals showed significantly increased transepidermal water loss (TEWL), skin blood flow and skin colour (red) as compared to a control group. However, the degree of skin sensitivity to SLS was not correlated with BMI. Basal biophysical parameters of the skin are primarily correlated with the BMI. This may be caused by obesity-induced physiological changes, e.g. increased sweat gland activity, high blood pressure and physiological temperature-regulating system. The epidermal barrier function, as evaluated after SLS patch testing is, however, not correlated with a high BMI, indicating a normal skin barrier.
NASA Astrophysics Data System (ADS)
Wong, Wing-Chun Godwin
This dissertation focused on Kant's conception of physical matter in the Opus postumum. In this work, Kant postulates the existence of an ether which fills the whole of space and time with its moving forces. Kant's arguments for the existence of an ether in the so-called Ubergang have been acutely criticized by commentators. Guyer, for instance, thinks that Kant pushes the technique of transcendental deduction too far in trying to deduce the empirical ether. In defense of Kant, I held that it is not the actual existence of the empirical ether, but the concept of the ether as a space-time filler that is subject to a transcendental deduction. I suggested that Kant is doing three things in the Ubergang: First, he deduces the pure concept of a space-time filler as a conceptual hybrid of the transcendental object and permanent substance to replace the category of substance in the Critique. Then he tries to prove the existence of such a space-time filler as a reworking of the First Analogy. Finally, he takes into consideration the empirical determinations of the ether by adding the concept of moving forces to the space -time filler. In reconstructing Kant's proofs, I pointed out that Kant is absolutely committed to the impossibility of action-at-a-distance. If we add this new principle of no-action-at-a-distance to the Third Analogy, the existence of a space-time filler follows. I argued with textual evidence that Kant's conception of ether satisfies the basic structure of a field: (1) the ether is a material continuum; (2) a physical quantity is definable on each point in the continuum; and (3) the ether provides a medium to support the continuous transmission of action. The thrust of Kant's conception of ether is to provide a holistic ontology for the transition to physics, which can best be understood from a field-theoretical point of view. This is the main thesis I attempted to establish in this dissertation.
2012-01-01
Background The main objective of this work was to obtain a binary system of surface-active components (nonionic soap – alkaline and/or ammonium dodecylbenzenesulfonate) with potential competences in food hygiene, by accessing a scheme of classical reactions (cyanoethylation, total acid hydrolysis and stoichiometric neutralization with inorganic alkaline and/or organic ammonium bases) adapted to heterogeneously polyethoxylated nonylphenols (n = 3-20). In the processing system mentioned, dodecylbenzenesulfonic acid, initially the acid catalyst for the exhaustive hydrolysis of β-nonylphenolpolyethyleneoxy (n = 3-20) propionitriles, becomes together with the nonionic soap formed the second surface-active component of the binary system. Results In the reaction scheme adopted the influence of the main operating (duration, temperature, molar ratio of reagents) and structural parameters (degree of oligomerization of the polyoxyethylene chain) on the processing yields for the synthetic steps was followed. The favorable role of the polyoxyethylene chain size is remarked, through its specific conformation and its alkaline cations sequestration competences on the yields of cyanoethylation, but also the beneficial influence of phase-transfer catalysts in the total acid hydrolysis step. The chemical stability of dodecylbenzenesulfonic acid (DBSH) at the temperature and strongly acidic pH of the reaction environment is confirmed. The controlled change of the amount of DBSH in the final binary system will later confer it potential colloidal competences in food hygiene receipts. Conclusions The preliminary synthetic tests performed confirmed the prospect of obtaining a broad range of useful colloidal competences in various food hygiene scenarios. PMID:22958389
Purification and characterization of the tween-hydrolyzing esterase of Mycobacterium smegmatis.
Tomioka, H
1983-01-01
An esterase hydrolyzing Tween 80 (polyoxyethylene sorbitan monooleate) was purified from sonicated cell lysates of Mycobacterium smegmatis ATCC 14468 by DEAE-cellulose, Sephadex G-150, phenyl Sepharose, and diethyl-(2-hydroxypropyl) aminoethyl column chromatography and by subsequent preparative polyacrylamide gel electrophoresis. The molecular weight was estimated to be 36,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 41,000 by gel filtration on a Sephadex G-150 column. The esterase contained a single polypeptide. The esterase was stable to heat treatment at 100 degrees C and to a wide range of pH. The temperature and pH optima for the hydrolysis of Tween 80 were 50 degrees C and 8.3, respectively. The esterase had a narrow substrate specificity; it exhibited a high activity only on compounds having both polyoxyethylene and fatty acyl moieties, such as Tweens. Monoacylglyceride was hydrolyzed more slowly by this esterase and this enzyme exhibited a nonspecific esterase activity on p-nitrophenyl acyl esters, especially those having short chain acyl moieties. The Km and Vmax were 19.2 mM and 1,670 mumol/min per mg of protein for Tween 20, 6.6 mM and 278 mumol/min per mg of protein for Tween 80, and 0.25 mM and 196 mumol/min per mg of protein for p-nitrophenyl acetate, respectively. Observations of the effects of various chemical modifications on the activity of the esterase indicated that tyrosine, histidine, arginine, and methionine (with tryptophan) residues may be active amino acids which play important roles in the expression of Tween 80-hydrolyzing activity of the enzyme. PMID:6885719
Boundary lubrication of formulated C-ethers in air to 300 C. 2: Organic acid additives
NASA Technical Reports Server (NTRS)
Jones, W. R., Jr.
1973-01-01
Friction and wear measurements were made on CVM M-50 steel lubricated with three C-ether (modified polyphenyl ether) formulations in dry and moist air. Results were compared to those obtained with a formulated Type 2 ester and the C-ether base fluid. A ball-on-disk sliding friction apparatus was used. Experimental conditions were a 1-kilogram load, a 17-meter/minute surface speed, and a 25 to 300 C (77 to 572 F) disk temperature range. The three C-ether formulations yielded better boundary lubricating characteristics than the Type 2 ester under most test conditions. All C-ether formulations exhibited higher friction coefficients than the ester from 150 to 300 C (302 to 572 F) and similar or lower values from 25 to 150 C (77 to 302 F).
Chemical degradation mechanisms of membranes for alkaline membrane fuel cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choe, Yoong-Kee; Henson, Neil J.; Kim, Yu Seung
2015-12-31
Chemical degradation mechanisms of membranes for alkaline membrane fuel cells have been investigated using density functional theory (DFT). We have elucidated that the aryl-ether moiety of membranes is one of the weakest site against attack of hydroxide ions. The results of DFT calculations for hydroxide initiated aryl-ether cleavage indicated that the aryl-ether cleavage occurred prior to degradation of cationic functional group. Such a weak nature of the aryl-ether group arises from the electron deficiency of the aryl group as well as the low bond dissociation energy. The DFT results suggests that removal of the aryl-ether group in the membrane shouldmore » enhance the stability of membranes under alkaline conditions. In fact, an ether fee poly(phenylene) membrane exhibits excellent stability against the attack from hydroxide ions.« less
Lee, Byeol-Nim; Son, Tae Yang; Park, Chi Hoon; Kim, Tae Hyun; Nam, Sang Yong
2018-09-01
In this study, various poly(ether ether ketone) were synthesized using three different monomers and the imidazolium group was introduced into synthesized poly(ether ether ketone)s by using substitution reaction. Synthesized polymers were used to prepare anion exchange membranes and to evaluate its properties. Thermal, chemical and structural properties were carried out using thermogravimetric analysis, nuclear magnetic resonance. The anion exchange membranes with different imidazolium moieties were characterized by several different analytical techniques such as water up take, ion exchange capacity, hydroxide conductivity for checking the possibility to apply the anion exchange membrane fuel cell. Consequently, results of characterization were studied to understand the correlation between stabilities of the membrane and functional group and polymer backbone structures. And we confirm membrane performance was improved by increasing imidazolium cation groups.
Keeping ether "en-vogue": the role of Nathan Cooley Keep in the history of ether anesthesia.
Guralnick, Walter C; Kaban, Leonard B
2011-07-01
In this report, we explore the little known role of Dr Nathan Cooley Keep in the dissemination of ether anesthesia in Boston. Keep was a prominent Boston dentist who, for a short time, taught and employed both William Morton and Horace Wells. He used ether anesthesia for a variety of dental and other surgical procedures requiring pain control. Keep administered ether to anesthetize Henry Wadsworth Longfellow's wife during the delivery of their daughter. This was the first use of ether for obstetric anesthesia. Dr Keep was also the first Dean of the Harvard Dental School and convinced the Massachusetts General Hospital to appoint a dentist to the staff of the hospital for the first time. Copyright © 2011 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Experimental and Calculational Studies of the Interactions of BF3 with Fluoroethers
NASA Technical Reports Server (NTRS)
Zehe, Michael J.; Morales, Wilfredo; Ball, David W.
1998-01-01
BF3 was co-condensed with (C2H5)2O, (CF3CH2)2O and (C2F5)2O in excess argon at 15 K. Infrared spectra of the matrices showed a definite Lewis acid-base interaction between BF3 and diethyl ether; a weak but definite interaction with bis(2,2,2,-trifluorodiethyl)ether, and no observable interaction with perfluorodiethyl ether. Molecular orbital (MO) calculations complemented the experimental observations by revealing that fluorine atoms on the ethers decreased electron localization about the oxygen atom. Thus, the experimental data and MO calculations indicated a clear trend between strength of interaction with BF3 and the degree of ether F substitution. The implications of the results for commercial perfluoro ether lubricant/metal oxide surface interactions are discussed.
Nakatsu, Noriyuki; Igarashi, Yoshinobu; Aoshi, Taiki; Hamaguchi, Isao; Saito, Masumichi; Mizukami, Takuo; Momose, Haruka; Ishii, Ken J; Yamada, Hiroshi
2017-01-01
Diethyl ether (ether) had been widely used in Japan for anesthesia, despite its explosive properties and toxicity to both humans and animals. We also had used ether as an anesthetic for euthanizing rats for research in the Toxicogenomics Project (TGP). Because the use of ether for these purposes will likely cease, it is required to select an alternative anesthetic which is validated for consistency with existing TGP data acquired under ether anesthesia. We therefore compared two alternative anesthetic candidates, isoflurane and pentobarbital, with ether in terms of hematological findings, serum biochemical parameters, and gene expressions. As a result, few differences among the three agents were observed. In hematological and serum biochemistry analysis, no significant changes were found. In gene expression analysis, four known genes were extracted as differentially expressed genes in the liver of rats anesthetized with ether, isoflurane, or pentobarbital. However, no significant relationships were detected using gene ontology, pathway, or gene enrichment analyses by DAVID and TargetMine. Surprisingly, although it was expected that the lung would be affected by administration via inhalation, only one differentially expressed gene was extracted in the lung. Taken together, our data indicate that there are no significant differences among ether, isoflurane, and pentobarbital with respect to effects on hematological parameters, serum biochemistry parameters, and gene expression. Based on its smallest affect to existing data and its safety profile for humans and animals, we suggest isoflurane as a suitable alternative anesthetic for use in rat euthanasia in toxicogenomics analysis.
Pan, Jianjun; Cheng, Xiaolin; Heberle, Frederick A.; Mostofian, Barmak; Kučerka, Norbert; Drazba, Paul; Katsaras, John
2012-01-01
Cholesterol and ether lipids are ubiquitous in mammalian cell membranes, and their interactions are crucial in ether lipid mediated cholesterol trafficking. We report on cholesterol’s molecular interactions with ether lipids as determined using a combination of small-angle neutron and X-ray scattering, and all-atom molecular dynamics (MD) simulations. A scattering density profile model for an ether lipid bilayer was developed using MD simulations, which was then used to simultaneously fit the different experimental scattering data. From the analysis of the data the various bilayer structural parameters were obtained. Surface area constrained MD simulations were also performed to reproduce the experimental data. This iterative analysis approach resulted in good agreement between the experimental and simulated form factors. The molecular interactions taking place between cholesterol and ether lipids were then determined from the validated MD simulations. We found that in ether membranes, cholesterol primarily hydrogen bonds with the lipid headgroup phosphate oxygen, while in their ester membrane counterparts, cholesterol hydrogen bonds with the backbone ester carbonyls. This different mode of interaction between ether lipids and cholesterol induces cholesterol to reside closer to the bilayer surface, dehydrating the headgroup’s phosphate moiety. Moreover, the three-dimensional lipid chain spatial density distribution around cholesterol indicates anisotropic chain packing, causing cholesterol to tilt. These insights lend a better understanding of ether lipid mediated cholesterol trafficking and the roles that the different lipid species have in determining the structural and dynamical properties of membrane associated biomolecules. PMID:23199292
Strategy for Restoring Drug Sensitivity to Triple-Negative Breast Cancer
2011-09-01
tocopherol ether-linked acetic acid analog -TEA), a non-hydrolyzable ether analog of RRR- - tocopherol in p53 mutant TNBC cells, and to understand...cells with a unique analog of vitamin E (alpha- tocopherol ether-linked acetic acid analog; abbreviated α-TEA) in combination with chemotherapeutic...p53-mutant, triple-negative breast cancer (TNBC) cells with a unique analog of vitamin E (alpha- tocopherol ether-linked acetic acid analog
Code of Federal Regulations, 2011 CFR
2011-07-01
...-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium salt. 721.4040 Section 721.4040 Protection of...-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetra-methylbutyl)phenyl ether, sodium salt. (a) Chemical..., polyethylene-, 3-sulfo-2-hydroxypropyl-p-(1,1,3,3-tetramethyl butyl)phenyl ether, sodium salt (P-90-1565) is...
Obligate methylotrophy: evaluation of dimethyl ether as a C1 compound.
Meyers, A J
1982-01-01
The suitability of dimethyl ether as a C1 compound was examined with the obligate methylobacterium Methylococcus capsulatus (Texas). The ether did not support growth and was not formed during growth on methane; it was an inhibitor of growth and oxidation of methane and a poor oxidation substrate for cell suspensions. NADH stimulation of methane, but not dimethyl ether, oxidation occurred in cell extracts. PMID:6802804
Crown Ethers in Nonaqueous Electrolytes for Lithium/Air Batteries
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Wu; Xiao, Jie; Wang, Deyu
2010-02-04
The effects of three crown ethers, 12-crown-4, 15-crown-5, and 18-crown-6, as additives and co-solvents in non-aqueous electrolytes on the cell performance of primary Li/air batteries operated in a dry air environment were investigated. Crown ethers have large effects on the discharge performance of non-aqueous electrolytes in Li/air batteries. A small amount (normally less than 10% by weight or volume in electrolytes) of 12-Crown-4 and 15-crown-5 reduces the battery performance and a minimum discharge capacity appears at the crown ether content of ca. 5% in the electrolytes. However, when the content increases to about 15%, both crown ethers improve the capacitymore » of Li/air cells by about 28% and 16%, respectively. 15-Crown-5 based electrolytes even show a maximum discharge capacity in the crown ether content range from 10% to 15%. On the other hand, the increase of 18-crown-6 amount in the electrolytes continuously lowers of the cell performance. The different battery performances of these three crown ethers in electrolytes are explained by the combined effects from the electrolytes’ contact angle, oxygen solubility, viscosity, ionic conductivity, and the stability of complexes formed between crown ether molecules and lithium ions.« less
Preparation, Fabrication, and Evaluation of Advanced Polymeric and Composite Materials
NASA Technical Reports Server (NTRS)
Orwoll, Robert A.
1997-01-01
The thesis titles are given below: physical and mechanical behavior of amorphous poly(arylene ether-co-imidasole)s and poly(arylene ether-co-imidasole) modification epoxies; the requirements of patentability as applied to the chemical arts; fabrication of thermoplastic polymer composite ribbon; blend of reactive diluents with phenylethynyl-terminated arylene ether oligomers; the synthesis, characterization, and application of ether-containing polyimides; the synthesis of reflective and electrically conductive polyimide films via an in-situ self-metalization procedure using silver (I) complexes; the thermal cure of phenylethynyl terminated polyimides and selected model compounds; and the synthesis, characterization, and molecular modeling of cyclic arylene ether oligomers.
NASA Astrophysics Data System (ADS)
Nikolić, G. M.; Živković, J. V.; Atanasković, D. S.; Nikolić, M. G.
2013-12-01
Liquid-liquid extraction of paracetamol from aqueous NaCl solutions was performed with diethyl ether, 1-propanol, 1-butanol, isobutanol, 1-pentanol, and binary mixtures diethyl ether/1-propanol, diethyl ether/1-butanol, and diethyl ether/isobutanol. Among the pure solvents investigated in this study best extraction efficacy was obtained with 1-butanol. Synergic effects in the extraction with binary mixtures was investigated and compared with some other systems used for the extraction of poorly extractable compounds. Results obtained in this study may be of both fundamental and practical importance.
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...
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...
Phenolic sodium sulphates of Frankenia laevis L.
Hussein, S A M
2004-04-01
Four new phenolic anionic conjugates have been isolated from the whole plant aqueous alcohol extract of Frankenia laevis L. Their structures were established, mainly on the basis of ESI-MS, 1D and 2D NMR spectroscopic evidence, as gallic acid-3-methyl ether-5-sodium sulphate, acetophenone-4-methyl ether-2-sodium sulphate, ellagic acid-3,3'-dimethyl ether-4,4'-di-sodium sulphate and ellagic acid-3-methyl ether-4-sodium sulphate.
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...
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...
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...
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...
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...
Code of Federal Regulations, 2013 CFR
2013-07-01
....- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers (PMN P-06-452; CAS No. 675869-05-3...-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-15-alkyl ethers. 721.10556 Section 721.10556 Protection of...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-15-alkyl ethers. (a) Chemical substance...
Code of Federal Regulations, 2014 CFR
2014-07-01
....- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers (PMN P-06-452; CAS No. 675869-05-3...-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-15-alkyl ethers. 721.10556 Section 721.10556 Protection of...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-15-alkyl ethers. (a) Chemical substance...
Code of Federal Regulations, 2013 CFR
2013-07-01
....- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers (PMN P-06-452; CAS No. 675869-05-3...-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers. 721.10558 Section 721.10558 Protection of...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers. (a) Chemical substance...
Code of Federal Regulations, 2014 CFR
2014-07-01
....- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers (PMN P-06-452; CAS No. 675869-05-3...-methyl-2-propen-1-yl) -.omega.-hydroxy-,C10-16-alkyl ethers. 721.10557 Section 721.10557 Protection of...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C10-16-alkyl ethers. (a) Chemical substance...
Code of Federal Regulations, 2014 CFR
2014-07-01
....- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers (PMN P-06-452; CAS No. 675869-05-3...-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers. 721.10558 Section 721.10558 Protection of...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers. (a) Chemical substance...
Code of Federal Regulations, 2013 CFR
2013-07-01
....- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers (PMN P-06-452; CAS No. 675869-05-3...-methyl-2-propen-1-yl) -.omega.-hydroxy-,C10-16-alkyl ethers. 721.10557 Section 721.10557 Protection of...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C10-16-alkyl ethers. (a) Chemical substance...
NASA Technical Reports Server (NTRS)
Hergenrother, P. M.; Havens, S. J.; Jensen, B. J.
1986-01-01
A series of new polyarylene ethers (PAEs) were prepared from the reaction of activated dihalo compounds with various bisphenols. Measured number average molecular weights for the PAEs ranged from 13,500 to 39,400 g/mole, and glass transition temperatures varied from 152 to 280 C. Ethynyl-terminated polyarylene ethers (ETPAEs) were also prepared by endcapping hydroxy-terminated polyarylene ethers with 4-ethynylbenzoyl chloride. Structure/property relationships for the PAEs, and the advantages offered by the ETPAEs, are discussed.
Planck's constant and the three waves (TWs) of Einstein's covariant ether
NASA Astrophysics Data System (ADS)
Kostro, L.
1985-11-01
The implications of a three-wave model for elementary particles, satisfying the principles of both quantum mechanics and General Relativity (GR), are discussed. In GR, the ether is the fundamental source of all activity, where particles (waves) arise at singularities. Inertia and gravity are field properties of the ether. In flat regions of the space-time geodesic, wave excitations correspond to the presence of particles. A momentum-carrying excitation which occurs in the ether is a superluminal radiation (phase- or B-waves) which transports neither energy nor mass. Superposition of the B-waves produces soliton-like excitations on the ether to form C-waves, i.e., particles. The particle-waves travel through space-time on D-waves, and experience reflection, refraction and interference only where B-waves have interacted with the ether. The original particles, photons-maximons, existed at the Big Bang and had physical properties which are describable in terms of Planck's quantities.
NASA Technical Reports Server (NTRS)
Slaby, Scott M.; Ewing, David W.; Zehe, Michael J.
1997-01-01
The AM1 semiempirical quantum chemical method was used to model the interaction of perfluoroethers with aluminum surfaces. Perfluorodimethoxymethane and perfluorodimethyl ether were studied interacting with aluminum surfaces, which were modeled by a five-atom cluster and a nine-atom cluster. Interactions were studied for edge (high index) sites and top (low index) sites of the clusters. Both dissociative binding and nondissociative binding were found, with dissociative binding being stronger. The two different ethers bound and dissociated on the clusters in different ways: perfluorodimethoxymethane through its oxygen atoms, but perfluorodimethyl ether through its fluorine atoms. The acetal linkage of perfluorodimeth-oxymethane was the key structural feature of this molecule in its binding and dissociation on the aluminum surface models. The high-index sites of the clusters caused the dissociation of both ethers. These results are consistent with the experimental observation that perfluorinated ethers decompose in contact with sputtered aluminum surfaces.
The Effect of Lengthening Cation Ether Tails on Ionic Liquid Properties
Lall-Ramnarine, S.; Rodriguez, C.; Fernandez, R.; ...
2016-08-30
In order to explore the effect of multiple ether functionalities on ionic liquid properties, a series of ten pyrrolidinium ionic liquids and ten imidazolium ionic liquids bearing ether and alkyl side chains of varying lengths (4 to 10 atoms in length) were prepared for this study. Their physical properties, such as viscosity, conductivity and thermal profile were measured and compared. Consistent with earlier literature, a single ether substituent substantially decreases the viscosity of pyrrolidinium and imidazolium ILs compared to their alkyl congeners. Remarkably, as the number of ether units in the pyrrolidinium ILs increases there is hardly any increase inmore » the viscosity, in contrast to alkylpyrrolidinium ILs where the viscosity increases steadily with chain length. Viscosities of imidazolium ether ILs increase with chain length but always remain well below their alkyl congeners. These results provide significant insight on the choice of starting materials for researchers designing ILs for specific applications.« less
Gupta, Avneet; Raj, Hem; Sharma, Bhartendu; Upmanyu, Neeraj
2014-04-01
Bacopa monnieri, Evolvulus alsinoides and Tinospora cordifolia are established ayurvedic herbs having neuropharmacological effect. In present study is aimed to Phytochemical Comparison between Pet ether and Ethanolic extracts of Bacopa monnieri (BME), Evolvulus alsinoides (EAE) and Tinospora cordifolia (TCE). To identify the presence (+) or absence (-) of different phytoconstituents in Pet ether and Ethanolic extracts of BME, EAE and TCE by using various phytochemical testing methods. Phytochemical investigation showed the presence of various phytochemical constituents in Pet ether and Ethanolic extracts of BME, EAE and TCE. When comparison between Pet ether and Ethanolic extracts of BME, EAE and TCE; Ethanolic extracts of these plants showed more phytoconstituents as compared to Pet ether extracts of these plants. From present investigation, it can be concluded that phytochemical comparison is subsequently momentous and useful in finding chemical constituents in the plant substances that may lead to their quantitative evaluation and also pharmacologically active chemical compounds.
Formulation and evaluation of C-Ether fluids as lubricants useful to 260 C. [air breathing engines
NASA Technical Reports Server (NTRS)
Clark, F. S.; Miller, D. R.
1980-01-01
Three base stocks were evaluated in bench and bearing tests to determine their suitability for use at bulk oil temperatures (BOT) from -40 C to +260 C. A polyol ester gave good bearing tests at a bulk temperature of 218 C, but only a partially successful run at 274 C. These results bracket the fluid's maximum operating temperature between these values. An extensive screening program selected lubrication additives for a C-ether (modified polyphenyl ether) base stock. One formulation lubricated a bearing for 111 hours at 274 C (BOT), but this fluid gave many deposit related problems. Other C-ether blends produced cage wear or fatigue failures. Studies of a third fluid, a C-ether/disiloxane blend, consisted of bench oxidation and lubrication tests. These showed that some additives react differently in the blend than in pure C-ethers.
Zheng, Xiaobo; Erratico, Claudio; Luo, Xiaojun; Mai, Bixian; Covaci, Adrian
2016-05-01
The in vitro oxidative metabolism of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), 2,2',4,4',5-pentabromodiphenyl ether (BDE-99), and individual α-, β- and γ-hexabromocyclododecane (HBCD) isomers catalyzed by cytochrome P450 (CYP) enzymes was screened using cat liver microsomes (CLMs). Six hydroxylated metabolites, namely 4-hydroxy-2,2',3,4'-tetrabromodiphenyl ether (4-OH-BDE-42), 3-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (3-OH-BDE-47), 5-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (5-OH-BDE-47), 6-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (6-OH-BDE-47), 4'-hydroxy-2,2',4,5'- tetrabromodiphenyl ether (4'-OH-BDE-49), and 2'-hydroxy-2,3',4,4'-tetrabromodiphenyl ether (2'-OH-BDE-66), were identified and quantified after incubation of BDE-47. A di-OH-tetra-BDE was also found as metabolite of BDE-47 with CLMs. 5-OH-BDE-47 was the major metabolite formed. Five hydroxylated metabolites (3'-hydroxy-2,2',4,4',5-pentabromodiphenyl ether (3'-OH-BDE-99), 5'-hydroxy-2,2',4,4',5-pentabromodiphenyl ether (5'-OH-BDE-99), 6-hydroxy-2,2',4,4',5-pentabromodiphenyl ether (6-OH-BDE-99), 6'-hydroxy-2,2',4,4',5-pentabromodiphenyl ether (6'-OH-BDE-99), and 4'-hydroxy-2,2',4,5,5'-pentabromodiphenyl ether (4'-OH-BDE-101) were formed from BDE-99 incubated with CLMs. Concentrations of BDE-99 metabolites were lower than those of BDE-47. Four or more mono-hydroxylated HBCD (OH-HBCDs), four or more di-hydroxylated HBCD (di-OH-HBCDs), five or more mono-hydroxylated pentabromocyclododecanes (OH-PBCDs), and five or more di-hydroxylated pentabromocyclododecenes (di-OH-PBCDs) were detected after incubation of α-, β-, or γ-HBCD with CLMs. No diastereoisomeric or enantiomeric enzymatic isomerisation was observed incubating α-, β- or γ-HBCD with CLMs. Collectively, our data suggest that (i) BDE-47 is metabolized at a faster rate than BDE-99 by CLMs, (ii) OH-HBCDs are the major hydroxylated metabolites of α-, β- and γ-HBCD produced by CLMs, and (iii) the oxidative metabolism of BDE-47 and BDE-99 is different by cat and human liver microsomes. This suggests that cats are not a suitable sentinel to represent internal exposure of PBDEs for humans, but is likely a promising sentinel for internal HBCDs exposure for humans. Copyright © 2016 Elsevier Ltd. All rights reserved.
Photosynthetic Reaction Centers as Active Molecular Electronic Components. Phase I
1993-08-13
lauryl dimethylarnine oxide (LDAO). This is followed by final purification by ion-exchange chromatography. Typical media are DEAE-Sephacel with an...should be less then 0.5 ml. Phenol extract two or three times and ethanol precipitate. Note: sulfates from the agarose inhibiting ligase reactions and...transformations was once a concern. Presently agarose from most sources is pretty sulfate free (BioRad is good in this respect and FMC claims that it is
NASA Astrophysics Data System (ADS)
Sato, Hiroyasu; Kusumoto, Yoshihumi; Nakashima, Nobuaki; Yoshihara, Keitaro
1980-04-01
The mechanism of enhancement in the energy transfer between rhodamine 6G and 3,3'-diethylthiacarbocyanine iodide by sodium lauryl sulfate in the premicellar region was studied by a picosecond laser technique. The Forster mechanism with an increased local concentration suggesting dye-rich induced micelle formation was concluded from the shape of the decay curve.
Evaluation of Procedures for Isolation of Nontuberculous Mycobacteria from Soil and Water
Kamala, T.; Paramasivan, C. N.; Herbert, Daniel; Venkatesan, P.; Prabhakar, R.
1994-01-01
Six methods of decontamination each for the isolation of mycobacteria from soil and water were compared. On the basis of the results obtained, three of the six methods for soil and two of the six methods for water were further evaluated. For both soil and water samples, the method using 3% sodium lauryl sulfate in combination with 1% NaOH yielded more positives than the other methods. PMID:16349208
Park, Chang-Beom; Song, Min Ju; Choi, Nak Woon; Kim, Sunghoon; Jeon, Hyun Pyo; Kim, Sanghun; Kim, Youngjun
2017-01-01
The objective of this study was to investigate the aquatic-toxic effects of glyoxal-containing cellulose ether with four different glyoxal concentrations (0%, 1.4%, 2.3%, and 6.3%) in response to global chemical regulations, e.g., European Union Classification, Labeling and Packaging (EU CLP). Toxicity tests of glyoxal-containing cellulose ether on 11 different microbial strains, Microcystis aeruginosa, Daphnia magna, and zebrafish embryos were designed as an initial stage of toxicity screening and performed in accordance with standardized toxicity test guidelines. Glyoxal-containing cellulose ether showed no significant toxic effects in the toxicity tests of the 11 freeze-dried microbial strains, Daphnia magna, and zebrafish embryos. Alternatively, 6.3% glyoxal-containing cellulose ether led to a more than 60% reduction in Microcystis aeruginosa growth after 7 days of exposure. Approximately 10% of the developmental abnormalities (e.g., bent spine) in zebrafish embryos were also observed in the group exposed to 6.3% glyoxal-containing cellulose ether after 6 days of exposure. These results show that 6.3% less glyoxal-containing cellulose ether has no acute toxic effects on aquatic organisms. However, 6.3% less glyoxal-containing cellulose ether may affect the health of aquatic organisms with long-term exposure. In order to better evaluate the eco-safety of cellulosic products containing glyoxal, further studies regarding the toxic effects of glyoxal-containing cellulose ether with long-term exposure are required. The results from this study allow us to evaluate the aquatic-toxic effects of glyoxal-containing cellulosic products, under EU chemical regulations, on the health of aquatic organisms. PMID:28335565
Tough poly(arylene ether) thermoplastics as modifiers for bismaleimides
NASA Technical Reports Server (NTRS)
Stenzenberger, H. D.; Roemer, W.; Hergenrother, P. M.; Jensen, B. J.
1989-01-01
Several aspects of research on thermoplastics as toughness modifiers are discussed, including the contribution of the backbone chemistry and the concentration of the poly(arylene ether) thermoplastic to fracture toughness, influence of the molecular weight of the poly(arylene ether) thermoplastic on neat resin fracture toughness, and the morphology of the thermoplastic modified networks. The results show that fracture toughness of brittle bismaleimide resins can be improved significantly with poly(arylene ether) thermoplastic levels of 20 percent by weight, and that high molecular weight poly(arylene ether) based on bisphenol A provides the highest degree of toughening. Preliminary composite evaluation shows that improvements in neat resin toughness translate into carbon fabric composite.
NASA Technical Reports Server (NTRS)
1983-01-01
The general principles of classical liquid chromatography and high pressure liquid chromatography (HPLC) are reviewed, and their advantages and disadvantages are compared. Several chromatographic techniques are reviewed, and the analytical separation of a C-ether liquid lubricant by each technique is illustrated. A practical application of HPLC is then demonstrated by analyzing a degraded C-ether liquid lubricant from full scale, high temperature bearing tests.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pan, Jianjun; Cheng, Xiaolin; Heberle, Frederick A
Cholesterol and ether lipids are ubiquitous in mammalian cell membranes, and their interactions are crucial in ether lipid mediated cholesterol trafficking. We report on cholesterol s molecular interactions with ether lipids as determined using a combination of small-angle neutron and Xray scattering, and all-atom molecular dynamics (MD) simulations. A scattering density profile model for an ether lipid bilayer was developed using MD simulations, which was then used to simultaneously fit the different experimental scattering data. From analysis of the data the various bilayer structural parameters were obtained. Surface area constrained MD simulations were also performed to reproduce the experimental data.more » This iterative analysis approach resulted in good agreement between the experimental and simulated form factors. The molecular interactions taking place between cholesterol and ether lipids were then determined from the validated MD simulations. We found that in ether membranes cholesterol primarily hydrogen bonds with the lipid headgroup phosphate oxygen, while in their ester membrane counterparts cholesterol hydrogen bonds with the backbone ester carbonyls. This different mode of interaction between ether lipids and cholesterol induces cholesterol to reside closer to the bilayer surface, dehydrating the headgroup s phosphate moiety. Moreover, the three-dimensional lipid chain spatial density distribution around cholesterol indicates anisotropic chain packing, causing cholesterol to tilt. These insights lend a better understanding of ether lipid-mediated cholesterol trafficking and the roles that the different lipid species have in determining the structural and dynamical properties of membrane associated biomolecules.« less
IRIS Toxicological Review of Decabromodiphenyl Ether (Final Report)
EPA announced the release of the final report, Toxicological Review of Decabromodiphenyl Ether: in support of the Integrated Risk Information System (IRIS). The updated Summary for Decabromodiphenyl Ether and accompanying toxicological review have been added to the IRIS Da...
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...
Du, Yong-Hua; Jia, Ren-Yong; Yin, Zhong-Qiong; Pu, Zhong-Hui; Chen, Jiao; Yang, Fan; Zhang, Yu-Qun; Lu, Yang
2008-10-20
The acaricidal activity of the petroleum ether extract, the chloroform extract and the acetic ether extract of neem (Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi larvae was tested in vitro. A complementary log-log (CLL) model was used to analyze the data of the toxicity tests. The results showed that at all test time points, the petroleum ether extract demonstrated the highest activity against the larvae of S. scabiei var. cuniculi, while the activities of the chloroform extract and the acetic ether extract were similar. The activities of both the petroleum ether extract and the chloroform extract against the larvae showed the relation of time and concentration dependent. The median lethal concentration (LC50) of the petroleum ether extract (1.3 microL/mL) was about three times that of the chloroform extract (4.1 microL/mL) at 24 h post-treatment. At the concentrations of 500.0 microL/mL, the median lethal time (LT50) of the petroleum ether extract and the chloroform extract was 8.4 and 9.6 h, respectively.
NASA Astrophysics Data System (ADS)
Shokuhi Rad, Ali; Sani, Emad; Binaeian, Ehsan; Peyravi, Majid; Jahanshahi, Mohsen
2017-04-01
In this study, we used density functional theory (DFT) to search on the adsorption properties of three important compounds of ether family; diethyl ether (DEE), ethyl methyl ether (EME), and dimethyl ether (DME) on the surface of Gallium doped graphene (GaG). We used three functionals (B3LYP, wb97xd, and MPW1PW91) for optimization and calculation of adsorption energy. After fully optimization, we scrutinized on the charge allocations on the adsorbed ethers as well as GaG (at the area of interaction) based on natural bond orbitals (NBO). Besides, we have calculated the amount of charge transfer upon adsorption of each analyte. We revel that GaG is an ideal adsorbent for chemisorption of all above-mentioned ethers. There is a little difference between the values of adsorption; -123.5, -120, and -118.3 kJ/mol (based on wb97xd) for DEE, EME, and DME, respectively. We found significant changes in the electronic structure of both adsorbent and adsorbate upon adsorption. Moreover, results of charge analyses confirm GaG is a p-type semiconductor.
Preparation of highly fluorinated diols containing ether linkages.
NASA Technical Reports Server (NTRS)
Rochow, S. E.; Stump, E. C., Jr.
1970-01-01
Hydroxy-terminated perfluoroethers and polyurethane resins derived from ethers have outstanding chemical resistance and good thermal properties. They can be used as potting compounds, coatings, and seals. The hydroxy-terminated ethers serve as intermediates in the synthesis of highly fluorinated elastomers and adhesives.
Inert Reassessment Document for Dimethyl Ether - CAS No. 115-10-6
The existing dimethyl ether exemption from the requirement of a tolerance under 40 CFR 180.930 is for use on animals only. Dimethyl ether is used as an inert ingredient in a variety of livestock insect sprays and foggers.
47. BUILDING NO. 519, ETHER AND ALCOHOL RECOVERY HOUSE, INTERIOR, ...
47. BUILDING NO. 519, ETHER AND ALCOHOL RECOVERY HOUSE, INTERIOR, 4TH LEVEL, LOOKING NORTH AT TOPS OF ALCOHOL AND ETHER DISTILLATION TOWERS. - Picatinny Arsenal, 500 Area, Powder Factory & Power House, State Route 15 near I-80, Dover, Morris County, NJ
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...
2003-08-01
into a separatory funnel. Distilled water was added to remove the acid from the ether phase. The layers were allowed to separate, and the water layer...The reaction mixtures were removed from the heat 2 hr after the last acrylic acid aliquot was added. The acrylated oils were purified via ether... remove inhibitor and any unreacted acid , the reaction mixture was ether extracted (25). The mixture was dissolved in diethyl ether and poured into a
NASA Technical Reports Server (NTRS)
Wolfe, James F.
1993-01-01
The goal of this research program was to synthesize a series of unique monomers of type I to be utilized at NASA-Langley in the preparation of new poly(arylene ether ketones), poly(arylene ether ketosulfones), and poly(arylene ether ketophosphine oxides). These A-A and A-B monomer systems, which possess activated aryl halide and/or phenolic end groups, are accessible via condensation reactions of appropriately substituted aryl acetonitrile carbanions with activated aryl dihalides followed by oxidative decyanation.
Antiñolo, M; Ocaña, A J; Aranguren, J P; Lane, S I; Albaladejo, J; Jiménez, E
2017-08-01
Unsaturated ethers are oxygenated volatile organic compounds (OVOCs) emitted by anthropogenic sources. Potential removal processes in the troposphere are initiated by hydroxyl (OH) radicals and photochemistry. In this work, we report for the first time the rate coefficients of the gas-phase reaction with OH radicals (k OH ) of 2-chloroethyl vinyl ether (2ClEVE), allyl ether (AE), and allyl ethyl ether (AEE) as a function of temperature in the 263-358 K range, measured by the pulsed laser photolysis-laser induced fluorescence technique. No pressure dependence of k OH was observed in the 50-500 Torr range in He as bath gas, while a slightly negative T-dependence was observed. The temperature dependent expressions for the rate coefficients determined in this work are: The estimated atmospheric lifetimes (τ OH ) assuming k OH at 288 K were 3, 2, and 4 h for 2ClEVE, AE and AEE, respectively. The kinetic results are discussed in terms of the chemical structure of the unsaturated ethers by comparison with similar compounds. We also report ultraviolet (UV) and infrared (IR) absorption cross sections (σ λ and σ(ν˜), respectively). We estimate the photolysis rate coefficients in the solar UV actinic region to be less than 10 -7 s -1 , implying that these compounds are not removed from the atmosphere by this process. In addition, from σ(ν˜) and τ OH , the global warming potential of each unsaturated ether was calculated to be almost zero. A discussion on the atmospheric implications of the titled compounds is presented. Copyright © 2017 Elsevier Ltd. All rights reserved.
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.
From ether theory to ether theology: Oliver Lodge and the physics of immortality.
Raia, Courtenay Grean
2007-01-01
This article follows the development of physicist Oliver Lodge's religio-scientific worldview, beginning with his reticent attraction to metaphysics in the early 1880s to the full formulation of his "ether theology" in the late 1890s. Lodge undertook the study of psychical phenomena such as telepathy, telekinesis, and "ectoplasm" to further his scientific investigations of the ether, speculating that electrical and psychical manifestations were linked phenomena that described the deeper underlying structures of the universe, beneath and beyond matter. For Lodge, to fully understand the ether was to force from the universe an ultimate Revelation, and psychical research, as the most modern and probatory science, was poised to replace religion as the means of that disclosure. (c) 2007 Wiley Periodicals, Inc.
IRIS TOXICOLOGICAL REVIEW OF DECABROMODIPHENYL ETHER (EXTERNAL REVIEW DRAFT)
The U.S. EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessments of congeners of polybrominated diphenyl ethers (PDBEs), this review is about Decabromodiphenyl Ether, or commonly referred to as decaBDE (BDE-209). ...
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Reaction product of alkylphenyl... Reaction product of alkylphenyl glycidyl ether, polyalkylenepolyamine, and alkyl diglycidyl dibenzene... identified generically as reaction product of alkylphenyl glycidyl ether, polyalkylenepolyamine, and alkyl...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Reaction product of alkylphenyl... Reaction product of alkylphenyl glycidyl ether, polyalkylenepolyamine, and alkyl diglycidyl dibenzene... identified generically as reaction product of alkylphenyl glycidyl ether, polyalkylenepolyamine, and alkyl...
IRON(III) NITRATE-CATALYZED FACILE SYNTHESIS OF DIPHENYLMETHYL (DPM) ETHERS FROM ALCOHOLS
Diphenyl methyl (DPM) ethers constitute important structural portion of some pharmaceutical entities and also as protective group for hydroxyl groups in synthetic chemistry. DPM ethers are normally prepared using concentrated acids or base as catalysts, which may result in the fo...
Code of Federal Regulations, 2010 CFR
2010-07-01
.... Ethylene Glycol MonobutylEther Acetate Chloroprene. Ethylene Glycol MonomethylEther Acetate Cumene (isopropylbenzene). Ethylene Glycol Dimethyl Ether Dibromoethane 1,2. Hexachlorobenzene Dichlorobenzene 1,4.... Ethylbenzene. Ethylene Oxide. Ethylene Dibromide. Hexachlorobutadiene. Hexachloroethane. Hexane-n. Methyl...
Seaborg, G.T.
1957-10-29
Methods for separating plutonium from the fission products present in masses of neutron irradiated uranium are reported. The neutron irradiated uranium is first dissolved in an aqueous solution of nitric acid. The plutonium in this solution is present as plutonous nitrate. The aqueous solution is then agitated with an organic solvent, which is not miscible with water, such as diethyl ether. The ether extracts 90% of the uraryl nitrate leaving, substantially all of the plutonium in the aqueous phase. The aqueous solution of plutonous nitrate is then oxidized to the hexavalent state, and agitated with diethyl ether again. In the ether phase there is then obtained 90% of plutonium as a solution of plutonyl nitrate. The ether solution of plutonyl nitrate is then agitated with water containing a reducing agent such as sulfur dioxide, and the plutonium dissolves in the water and is reduced to the plutonous state. The uranyl nitrate remains in the ether. The plutonous nitrate in the water may be recovered by precipitation.
Toxicokinetics of ethers used as fuel oxygenates.
Dekant, W; Bernauer, U; Rosner, E; Amberg, A
2001-10-15
The toxicokinetics and biotransformation of methyl-tert.butyl ether (MTBE), ethyl-tert.butyl ether (ETBE) and tert.amyl-methyl ether (TAME) in rats and humans are summarized. These ethers are used as gasoline additives in large amounts, and thus, a considerable potential for human exposure exists. After inhalation exposure MTBE, ETBE and TAME are rapidly taken up by both rats and humans; after termination of exposure, clearance by exhalation and biotransformation to urinary metabolites is rapid in rats. In humans, clearance by exhalation is slower in comparison to rats. Biotransformation of MTBE and ETBE is both qualitatively and quantitatively similar in humans and rats after inhalation exposure under identical conditions. The extent of biotransformation of TAME is also quantitatively similar in rats and humans; the metabolic pathways, however, are different. The results suggest that reactive and potentially toxic metabolites are not formed during biotransformation of these ethers and that toxic effects of these compounds initiated by covalent binding to cellular macromolecules are unlikely.
Maleate/vinyl ether UV-cured coatings: Effects of composition on curing and properties
DOE Office of Scientific and Technical Information (OSTI.GOV)
Noren, G.K.
1996-10-01
The effect of the composition of the maleate polyester and the vinyl ether terminated compound on their UV-curing and properties has been investigated. Linear unsaturated polyester resins based on maleic anhydride and 1,5-pentane diol were synthesized. The molecular weight of the unsaturated polyesters was varied by changing the ratio of maleic anhydride to 1,5-pentane diol and the double bond equivalent weight was varied by replacing maleic anhydride with succinic anhydride. Coating formulations containing these unsaturated polyesters, triethylene glycol divinyl ether and a free radical photoinitiator were crosslinked in the presence of UV light. The coatings were very brittle, exhibiting tensilemore » strengths in the range of 1.5-4.0 MPa and elongations of only 3-7%. Diethyl maleate and isobutyl vinyl ether were effective diluents for reducing viscosity but reduced the cure speed. A vinyl ether urethane oligomer was synthesized and enhanced the flexibility and toughness of the coatings when substituted for triethylene glycol divinyl ether.« less
Stewart, Marie; Guertal, William R.; Barbaro, Jeffrey R.; McHale, Timothy J.
2004-01-01
A joint study by the Dover National Test Site, Dover Air Force Base, Delaware, and the U.S. Geological Survey was conducted from June 27 through July 18, 2001, to determine the spatial distribution of the gasoline oxygenate additive methyl tert-butyl ether and selected water-quality constituents in the surficial aquifer underlying the Dover National Test Site. This report provides a summary assessment of the distribution of methyl tert-butyl ether and a preliminary screening of selected constituents that may affect natural attenuation and remediation demonstrations at the Dover National Test Site. The information gathered during this study is designed to assist potential remedial investigators who are considering conducting a methyl tert-butyl ether remedial demonstration at the test site. In addition, the study supported a planned enhanced bioremediation demonstration and assisted the Dover National Test Site in identifying possible locations for future methyl tert-butyl ether remediation demonstrations. A direct-push drill rig was used to collect a total of 147 ground-water samples (115 VOC samples and 32 quality-assurance samples) at varying depths. Volatile organic compounds were above the method reporting limits in 59 of the 115 ground-water samples. The concentrations ranged from below detection limits to maximum values of 12.4 micrograms per liter of cis-1,2-dichloro-ethene, 1.14 micrograms per liter of trichloro-ethene, 2.65 micrograms per liter of tetrachloro-ethene, 1,070 micrograms per liter of methyl tert-butyl ether, 4.36 micrograms per liter of benzene, and 1.8 micrograms per liter of toluene. Vinyl chloride, ethylbenzene, p,m-xylene, and o-xylene were not detected in any of the samples collected during this investigation. Methyl tert-butyl ether was detected in 47 of the 115 ground-water samples. The highest concentrations of methyl tert-butyl ether were detected in the surficial aquifer from ?4.6 to 6.4 feet mean sea level; however, methyl tert-butyl ether was detected as deep as ?9.5 feet mean sea level. Increased methane concentrations and decreased dissolved oxygen concentrations that were found in association with the ground-water samples that contained methyl tert-butyl ether are preliminary indicators that will assist in determining if natural attenuation of methyl tert-butyl ether is occurring in the surficial aquifer. A full assessment of natural attenuation of methyl tert-butyl ether at the site is beyond the scope of this study, but the data collected during the study will be useful in selecting appropriate remedial methyl tert-butyl ether demonstrations.
INFLUENCE OF ANESTHESIA ON EXPERIMENTAL NEUROTROPIC VIRUS INFECTIONS
Sulkin, S. Edward; Zarafonetis, Christine
1947-01-01
1. Experimental neurotropic virus infections previously shown to be altered by ether anesthesia are caused by viruses destroyed in vitro by anesthetic ether; this group includes the viruses of Eastern equine encephalomyelitis, Western equine encephalomyelitis, and St. Louis encephalitis. 2. Experimental neurotropic virus infections which were not altered by ether anesthesia are caused by viruses which are refractory to the in vitro virucidal activity of even large amounts of anesthetic ether; this group includes the viruses of poliomyelitis (Lansing) and rabies. 3. Quantitative studies of the in vitro virucidal activity of ether indicate that concentrations of this anesthetic within the range found in central nervous system tissues of anesthetized animals possess no virucidal activity. 4. The lowest concentration of ether possessing significant virucidal capacity is more than fifteen times the maximum concentration of the anesthetic tolerated by the experimental animal. 5. Concentrations of ether 50 to 100 times the maximum amount tolerated by the anesthetized animal are capable of destroying large amounts of susceptible viruses, the average lethal dose (LD50) being reduced more than 5 log units. 6. On the basis of the studies presented in this report, it cannot be concluded that direct virucidal activity of ether is not the underlying mechanism of the inhibition by anesthesia of certain experimental neurotropic virus infections. Indirect inhibition of the virus by the anesthetic through an alteration in the metabolism of either the host cell or the host animal as a whole appears at this point to be a more likely possibility. PMID:19871636
α-Diazo oxime ethers for N-heterocycle synthesis.
Choi, Subin; Ha, Sujin; Park, Cheol-Min
2017-06-01
This Feature Article introduces the preparation and synthetic utility of α-diazo oxime ethers. α-Oximino carbenes are useful synthons for N-heterocycles, and can be easily prepared from α-diazo oxime ethers as precursors. We begin with the preparation of α-diazo oxime ethers and their application in [3+2] cycloaddition. It turns out that the nature of metals bound to carbenes plays a crucial role in modulating the reactivity of α-oximino carbenes, in which copper carbenes smoothly react with enamines, whereas the less reactive enol ethers and nitriles require gold carbenes. In Section 3.2, a discussion on N-O and C-H bond activation is presented. Carbenes derived from diazo oxime ethers show unique reactivity towards N-O and C-H bond activation, in which the proximity of the two functionalities, carbene and oxime ether, dictates the preferred reaction pathways toward pyridines, pyrroles, and 2H-azirines. In Section 3.3, the development of tandem reactions based on α-diazo oxime ethers is discussed. The nature of carbenes in which whether free carbenes or metal complexes are involved dissects the pathway and forms different types of 2H-azirines. The 2H-azirine formation turned out to be an excellent platform for the tandem synthesis of N-heterocycles including pyrroles and pyridines. In the last section, we describe the electrophilic activation of 2H-azirines with vinyl carbenes and oximino carbenes. The resulting azirinium species undergo rapid ring expansion rearrangements to form pyridines and pyrazines.
NASA Astrophysics Data System (ADS)
Long, B. E.; Dechirico, F.; Cooke, S. A.
2012-06-01
The conformational preferences of the O-C-C-C unit are important in many biological systems with the unit generally preferring a gauche configuration compared to an anti configuration. Butyl methyl ether and propyl methyl ether provide very simple systems for this phenomenom to manifest. Pure rotational spectra of the title molecules have been recorded using chirped pulse Fourier transform microwave spectroscopy (CP-FTMW). In the case of butyl methyl ether, only one conformer has been observed. This conformer has torsional angles of COCC = 180°, OCCC = 62° and CCCC = 180° (anti-gauche-anti) and rotational constants of A = 10259.4591(33) MHz, B = 1445.6470(13) MHz, and C = 1356.2944(14) MHz. The rotational spectrum was doubled and has been analyzed to produce an effective barrier to methyl group internal rotation of 780(35) cm-1. A prior rotational spectroscopic study on propyl methyl ether had focused only on the high energy anti-anti conformer. We have analyzed spectra from the lowest energy anti-gauche conformer and the spectroscopic constants will be presented. A summary of the differences in conformational energies and methyl group internal rotation barriers for the class of aliphatic asymmetric ethers will be presented. K. N. Houk, J. E. Eksterowicz, Y.-D. Wu, C. D. Fuglesang, D. B. Mitchell. J. Am. Chem. Soc. 115 (4170), 1993. Hiroshi Kato, Jun Nakagawa, Michiro Hayashi. J. Mol. Spectrosc. 80 (272), 1980.
Blood Substitutes: Effects on Drug Pharmacokinetics.
1984-03-01
stream of nitrogen gas. The residue was dissolved in 50 pl of mobile phase (45:55 acetonitrile:water, v/v; 0.50 g sodium lauryl sulfate /L; and 6.0 ml...concentrations of DZ were determined by HPLC. A mobile phase con- * sisting of 36:64 acetonitrile:water (v:v) with 1 g/L sodium dodecyl sulfate and 6.0...San Francisco, CA. d. Morphine Morphine sulfate Injectable, 10 mg/ml, was obtained from Wyeth, Philadelphia, PA. Morphine sulfate reference standard
Study of enhanced photogalvanic effect of Naphthol Green B in natural sunlight
NASA Astrophysics Data System (ADS)
Koli, Pooran
2015-07-01
The photogalvanic cells based on Naphthol Green B sensitizer-Fructose reductant-Sodium Lauryl Sulphate surfactant has been studied in natural sunlight. The cell has been found workable in natural sunlight with greatly enhanced optimum cell performance. The 1159.2 μW power, 4500 μA short-circuit current, 1070 mV open-circuit potential, 14.49% efficiency and 240 min storage capacity (as half change time) has been observed in optimum cell fabrication conditions.
Proksch, E; Nissen, H P
2002-12-01
Dexpanthenol-containing creams have been widely used for treatment of lesions (superficial wounds) of the skin and mucous membranes. Dexpanthenol is converted in tissues to pantothenic acid, a component of coenzyme A. Coenzyme A catalyses early steps in the synthesis of fatty acids and sphingolipids which are of crucial importance for stratum corneum lipid bilayers and cell membrane integrity. In the present study, the effects were examined of a dexpanthenol-containing cream on skin barrier repair, stratum corneum hydration, skin roughness, and inflammation after sodium lauryl sulphate (SLS)-induced irritation. Irritation was induced by application of SLS in patch test chambers. The dexpanthenol-contaming cream or the vehicle were applied twice daily and barrier repair, hydration, roughness, and inflammation of the skin were determined by using biophysical methods. Significantly accelerated skin barrier repair was found in treatments with the dexpanthenol-containing cream (verum) compared with vehicle-treated (placebo) or untreated skin. Both verum and placebo showed an increase in stratum corneum hydration, but significantly more so with the dexpanthenol-containing cream. Both creams reduced skin roughness, but again the verum was superior. The dexpanthenol-containing cream significantly reduced skin redness as a sign of inflammation in contrast to the vehicle, which produced no effect. Treatment with a dexpanthenol-containing cream showed significantly enhanced skin barrier repair and stratum corneum hydration, while reducing skin roughness and inflammation.
Huang, Huey-Chun; Chang, Tsong-Min
2008-08-01
Stratum corneum intercellular lipids, such as ceramides, play an important role in the regulation of skin water barrier homeostasis and water-holding capacity. Aim To evaluate the potential water retention capacity of control emulsion and three oil-in-water (o/w) emulsions containing ceramide 1, ceramide 3, or both. Fifteen healthy Asian women (age, 20-30 years) with healthy skin, pretreated with sodium lauryl sulfate (SLS), applied the tested emulsions twice daily over a period of 28 days. Skin hydration and transepidermal water loss (TEWL) values were measured on the indicated days with a Corneometer(R)825 and a TEWAMETER TM210, respectively. The maximum increase in skin humidity was reached after 4 weeks, with values of 21.9 +/- 1.8% and 8.9 +/- 0.9% for emulsion C and control emulsion, respectively. The maximum decrease in TEWL was also reached after 4 weeks, with values of 36.7 +/- 4.7% and 5.1 +/- 0.8% for the same emulsions. It can be concluded that all the tested ceramide-containing emulsions improved skin barrier function when compared with untreated skin. There was some indication that ceramides 1 and 3 contained in emulsion C might exert a beneficial synergistic effect on skin biochemical properties, such as skin hydration and TEWL, and play a key role in the protection mechanism against SLS irritation.
Törmä, Hans; Lindberg, Magnus; Berne, Berit
2008-05-01
Detergents are skin irritants affecting keratinocytes. In this study, healthy volunteers were exposed to water (vehicle) and 1% sodium lauryl sulfate (SLS) under occlusive patch tests for 24 hours. The messenger RNA (mRNA) expression of keratinocyte differentiation markers and of enzymes involved in corneodesmosome degradation was examined in skin biopsies (n=8) during the repair phase (6 hours to 7 days postexposure) using real-time reverse-transcription PCR. It was found that the expression of involucrin was increased at 6 hours, but then rapidly normalized. The expression of transglutaminase 1 exhibited a twofold increase after 24 hours in the SLS-exposed skin. Profilaggrin was decreased after 6 hours. Later (4-7 days), the expression in SLS-exposed areas was >50% above than in control areas. An increased and altered immunofluorescence pattern of involucrin, transglutaminase 1, and filaggrin was also found (n=4). At 6 hours post-SLS exposure, the mRNA expression of kallikrein-7 (KLK-7) and kallikrein-5 (KLK-5) was decreased by 50 and 75%, respectively, as compared with control and water-exposed areas. Thereafter, the expression pattern of KLK-7 and KLK-5 was normalized. Changes in protein expression of KLK-5 were also found. In conclusion, SLS-induced skin barrier defects induce altered mRNA expression of keratinocyte differentiation markers and enzymes degrading corneodesmosomes.
Shim, Y J; Choi, J-H; Ahn, H-J; Kwon, J-S
2012-10-01
To compare the effects of sodium lauryl sulfate (SLS)-free and SLS-containing dentifrice in patient with recurrent aphthous stomatitis (RAS). The design of this study was a double-blind crossover trial. The 90 subjects were divided into three groups: group I used SLS-free (a commercially available SLS-free dentifrice) and SLS-A (SLS-free + 1.5% SLS), group II used SLS-A and SLS-B (a commercially available 1.5% SLS-containing dentifrice), and group III used SLS-free and SLS-B. The subjects used one of the two assigned dentifrices for 8 weeks and then the other for the following 8 weeks. The order of the dentifrices used was selected at random, and there was a 2-week washout period between the two phases. The clinical parameters (number of ulcers, number of episodes, duration of ulcers, mean pain score) were compared between the two phases for each group. The number of ulcers and episodes did not differ significantly between SLS-A, SLS-B, and SLS-free. Only duration of ulcers and mean pain score was significantly decreased during the period using SLS-free. Although SLS-free did not reduce the number of ulcers and episodes, it affected the ulcer-healing process and reduces pain in daily lives in patients with RAS. © 2012 John Wiley & Sons A/S.
Kwon, Jae-Sung; Lee, Sang-Bae; Kim, Kwang-Mahn; Kim, Kyoung-Nam
2014-11-01
Vinyl polysiloxane (VPS) is elastomeric dental impression material which, despite having very few reports of adverse reactions, has shown high levels of cytotoxicity that is difficult to be interpreted without referencing to the positive control material. Therefore, in this study, positive control VPS was developed using sodium lauryl sulfate (SLS) for the reference of cytotoxicity test. The positive control VPS with SLS was formed with a different proportion of SLS (0, 1, 2, 4, 8 and 16 wt%) added to the base. The cytotoxicity test was then carried out using the extractions or dilutions of the extractions from each of the test samples using murine fibroblast cells (L929). The final product of positive control VPS behaved similar to commercially available VPS; being initially liquid-like and then becoming rubber-like. Ion chromatography showed that the level of SLS released from the product increased as the proportion of added SLS increased, consequently resulting in an increased level of cytotoxicity. Also, the commercially available VPS was less cytotoxic than the positive control VPS with more or equal to 2 wt% of SLS. However, even the VPS with the highest SLS (16 wt%) did not cause oral mucosa irritation during the animal study. The positive control VPS was successfully produced using SLS, which will be useful in terms of providing references during in vitro cytotoxicity testing.
Piret, Jocelyne; Désormeaux, André; Cormier, Hélène; Lamontagne, Julie; Gourde, Pierrette; Juhász, Julianna; Bergeron, Michel G.
2000-01-01
The influence of sodium lauryl sulfate (SLS) on the efficacies of topical gel formulations of foscarnet against herpes simplex virus type 1 (HSV-1) cutaneous infection has been evaluated in mice. A single application of the gel formulation containing 3% foscarnet given 24 h postinfection exerted only a modest effect on the development of herpetic skin lesions. Of prime interest, the addition of 5% SLS to this gel formulation markedly reduced the mean lesion score. The improved efficacy of the foscarnet formulation containing SLS could be attributed to an increased penetration of the antiviral agent into the epidermis. In vitro, SLS decreased in a concentration-dependent manner the infectivities of herpesviruses for Vero cells. SLS also inhibited the HSV-1 strain F-induced cytopathic effect. Combinations of foscarnet and SLS resulted in subsynergistic to subantagonistic effects, depending on the concentration used. Foscarnet in phosphate-buffered saline decreased in a dose-dependent manner the viability of cultured human skin fibroblasts. This toxic effect was markedly decreased when foscarnet was incorporated into the polymer matrix. The presence of SLS in the gel formulations did not alter the viabilities of these cells. The use of gel formulations containing foscarnet and SLS could represent an attractive approach to the treatment of herpetic mucocutaneous lesions, especially those caused by acyclovir-resistant strains. PMID:10952566
Improving the hardness of dry granulated tablets containing sodium lauryl sulfate.
Moore, Francis; Okelo, Geoffrey; Colón, Ivelisse; Kushner, Joseph
2010-11-15
The impact of the addition of a wetting agent, the surfactant sodium lauryl sulfate (SLS), on the tablet hardness of a dry granulated, solid oral dosage form was investigated. In three batches, SLS was added concurrently with: (1) a poorly soluble, highly hydrophobic active pharmaceutical ingredient (API) and the other excipients prior to the initial blending step, (2) magnesium stearate prior to roller compaction, or (3) magnesium stearate prior to tableting. A fourth batch, which did not contain SLS, served as a control. The maximum hardness of 100 mg, 1/4″-SRC tablets for the four batches--SLS added initially, prior to roller compaction, prior to tableting, and no SLS--were 61±3, 71±3, 89±5, and 86±3N, respectively, suggesting reduced processing of SLS improves tablet hardness by ∼50%. Dissolution of the tablets in 900 ml of simulated gastric fluid with paddles at 75 rpm showed that: (1) there was no impact on the insertion point of SLS into the process on API dissolution, and (2) that the presence of SLS improved dissolution by 5% compared to the control tablets. Adding SLS just prior to tableting can improve tablet hardness and yield similar dissolution performance relative to SLS addition prior to the initial blending step. Copyright © 2010 Elsevier B.V. All rights reserved.
Jung, Hyuck Jun; Ahn, Hye In; Park, Ji Yeon; Ho, Myoung Jin; Lee, Dae Ro; Cho, Ha Ra; Park, Jun Seo; Choi, Yong Seok; Kang, Myung Joo
2016-02-01
A novel surfactant-incorporated hydroxypropyl methylcellulose (HPMC) solid dispersion (SD) system was constructed in order to facilitate the release rate and oral absorption of tacrolimus (FK506), a poorly water-soluble immunosuppressant. Several emulsifiers including sodium lauryl sulfate (SLS), as drug release promotors, were employed with HPMC to fabricate SD using the solvent wetting method. The solid state characteristics using differential scanning calorimetry and X-ray powder diffraction, revealed that FK506 was molecularly distributed within all dispersions in amorphous form. The dissolution rates of FK506 in SLS-incorporated SDs were much higher than those in SDs prepared with HPMC alone, and even with stearoyl polyoxyl-32 glycerides or tocopheryl polyethylene glycol 1000 succinate. In particular, the greatest dissolution enhancement was obtained from the SD consisting of the drug, HPMC, and SLS in a weight ratio of 1:1:3, providing a 50-fold higher drug concentration within 15 min, compared with HPMC SD. In vivo absorption study in rats demonstrates that the optimized formula remarkably increased the oral absorption of FK506, providing about 4.0-fold greater bioavailability (p<0.05) compared with the marketed product (Prograf®, Astellas Pharma). These data suggest that a novel SLS/HPMC SD may be an advantageous dosage form of FK506, boosting the dissolution and absorption in gastrointestinal tract. Copyright © 2015 Elsevier B.V. All rights reserved.
Polat, Baris E; Figueroa, Pedro L; Blankschtein, Daniel; Langer, Robert
2011-02-01
Recent advances in transdermal drug delivery utilizing low-frequency sonophoresis (LFS) and sodium lauryl sulfate (SLS) have revealed that skin permeability enhancement is not homogenous across the skin surface. Instead, highly perturbed skin regions, known as localized transport regions (LTRs), exist. Despite these findings, little research has been conducted to identify intrinsic properties and formation mechanisms of LTRs and the surrounding less-perturbed non-LTRs. By independently analyzing LTR, non-LTR, and total skin samples treated at multiple LFS frequencies, we found that the pore radii (r(pore)) within non-LTRs are frequency-independent, ranging from 18.2 to 18.5 Å, but significantly larger than r(pore) of native skin samples (13.6 Å). Conversely, r(pore) within LTRs increase significantly with decreasing frequency from 161 to 276 Å and to ∞ (>300 Å) for LFS/SLS-treated skin at 60, 40, and 20 kHz, respectively. Our findings suggest that different mechanisms contribute to skin permeability enhancement within each skin region. We propose that the enhancement mechanism within LTRs is the frequency-dependent process of cavitation-induced microjet collapse at the skin surface, whereas the increased r(pore) values in non-LTRs are likely due to SLS perturbation, with enhanced penetration of SLS into the skin resulting from the frequency-independent process of microstreaming. Copyright © 2010 Wiley-Liss, Inc.
Limpongsa, Ekapol; Jaipakdee, Napaphak; Pongjanyakul, Thaned
2014-08-27
Abstract The objective of this study was to investigate the effects of propylene glycol (PG), ethanol (EtOH) and sodium lauryl sulfate (SLS) on the in vitro deposition and permeation of finasteride (FNS). A side-by-side diffusion cell mounted with a pig ear skin and a saturated solution of FNS in PG (10, 20% v/v), EtOH (10, 20% v/v) or SLS (0.5, 1% w/v) vehicles were used. Incorporation of PG, EtOH or SLS caused a significant increase in FNS solubility both in the solution and on the skin with SLS > EtOH > PG. The results obtained from skin deposition studies showed that the FNS deposition rate and time increased in the same order as that of the solubility. The deposition kinetics of FNS solubilized in PG, EtOH and SLS vehicles followed either zero-order, square-root-of-time or pseudo-first-order kinetic models depending on the type and concentration of the enhancer. The permeation studies demonstrated that FNS permeation fluxes were enhanced only by EtOH vehicles. These results suggest that PG and SLS could be used as deposition enhancers, while EtOH could be the effective permeation enhancer of FNS. The obtained results can be used as the considerable insights for formulating the topical and transdermal products of FNS.
Lopez, Renata F.V.; Seto, Jennifer E.; Blankschtein, Daniel; Langer, Robert
2010-01-01
The potential of rigid nanoparticles to serve as transdermal drug carriers can be greatly enhanced by improving their skin penetration. Therefore, the simultaneous application of ultrasound and sodium lauryl sulfate (referred to as US/SLS) was evaluated as a skin pre-treatment method for enhancing the passive transdermal delivery of nanoparticles. We utilized inductively-coupled plasma mass spectrometry and an improved application of confocal microscopy to compare the delivery of 10- and 20-nm cationic, neutral, and anionic quantum dots (QDs) into US/SLS-treated and untreated pig split-thickness skin. Our findings include: (a) ~0.01% of the QDs penetrate the dermis of untreated skin (which we quantify for the first time), (b) the QDs fully permeate US/SLS-treated skin, (c) the two cationic QDs studied exhibit different extents of skin penetration and dermal clearance, and (d) the QD skin penetration is heterogeneous. We discuss routes of nanoparticle skin penetration and the application of the methods described herein to address conflicting literature reports on nanoparticle skin penetration. We conclude that US/SLS treatment significantly enhances QD transdermal penetration by 500–1300%. Our findings suggest that an optimum surface charge exists for nanoparticle skin penetration, and motivate the application of nanoparticle carriers to US/SLS-treated skin for enhanced transdermal drug delivery. PMID:20971504
Polat, Baris E.; Seto, Jennifer E.; Blankschtein, Daniel; Langer, Robert
2011-01-01
This study investigated the effect of sodium lauryl sulfate (SLS) on skin structural perturbation when utilized simultaneously with low-frequency sonophoresis (LFS). Pig full-thickness skin (FTS) and pig split-thickness skin (STS) treated with LFS/SLS and LFS were analyzed in the context of the aqueous porous pathway model to quantify skin perturbation through changes in skin pore radius and porosity-to-tortuosity ratio (ε/τ). In addition, skin treatment times required to attain specific levels of skin electrical resistivity were analyzed to draw conclusions about the effect of SLS on reproducibility and predictability of skin perturbation. We found that LFS/SLS-treated FTS, LFS/SLS-treated STS, and LFS-treated FTS exhibited similar skin perturbation. However, LFS-treated STS exhibited significantly higher skin perturbation, suggesting greater structural changes to the less robust STS induced by the purely physical enhancement mechanism of LFS. Evaluation of ε/τ values revealed that LFS/SLS-treated FTS and STS have similar transport pathways, while LFS-treated FTS and STS have lower ε/τ values. In addition, LFS/SLS treatment times were much shorter than LFS treatment times for both FTS and STS. Moreover, the simultaneous use of SLS and LFS not only results in synergistic enhancement, as reflected in the shorter skin treatment times, but also in more predictable and reproducible skin perturbation. PMID:20963845
Polat, Baris E.; Figueroa, Pedro L.; Blankschtein, Daniel; Langer, Robert
2011-01-01
Recent advances in transdermal drug delivery utilizing low-frequency sonophoresis (LFS) and sodium lauryl sulfate (SLS) have revealed that skin permeability enhancement is not homogenous across the skin surface. Instead, highly perturbed skin regions, known as localized transport regions (LTRs), exist. Despite these findings, little research has been conducted to identify intrinsic properties and formation mechanisms of LTRs and the surrounding less-perturbed non-LTRs. By independently analyzing LTR, non-LTR, and total skin samples treated at multiple LFS frequencies, we found that the pore radii (rpore) within non-LTRs are frequency-independent, ranging from 18.2 – 18.5 Å, but significantly larger than rpore of native skin samples (13.6 Å). Conversely, rpore within LTRs increases significantly with decreasing frequency from 161 Å, to 276 Å, and to ∞ (>300Å) for LFS/SLS-treated skin at 60 kHz, 40 kHz, and 20 kHz, respectively. Our findings suggest that different mechanisms contribute to skin permeability enhancement within each skin region. We propose that the enhancement mechanism within LTRs is the frequency-dependent process of cavitation-induced microjet collapse at the skin surface, while the increased rpore values in non-LTRs are likely due to SLS perturbation, with enhanced penetration of SLS into the skin resulting from the frequency-independent process of microstreaming. PMID:20740667
Piret, Jocelyne; Lamontagne, Julie; Désormeaux, André; Bergeron, Michel G.
2001-01-01
The influence of sodium lauryl sulfate (SLS) on the efficacies of gel formulations of foscarnet against herpes simplex virus type 1 (HSV-1) cutaneous lesions and on the establishment and reactivation of latent virus has been evaluated in a murine model of orofacial infection. Topical treatments were given twice daily for 3 days and were initiated at 6, 24, and 48 h after virus inoculation. The gel formulation that contained both 3% foscarnet and 5% SLS and that was administered within 48 h postinfection reduced the rate of development of herpetic skin lesions. This formulation also significantly decreased the viral content in skin tissues and in ipsilateral trigeminal ganglia when it was given within 24 and 6 h postinfection, respectively. A lower level of efficacy was observed for the gel formulation containing 3% foscarnet alone. Of prime interest, the gel formulation containing 5% SLS reduced significantly the mortality rate among mice in a zosteriform model of infection. Both formulations of foscarnet had no effect on the mean titers of reactivated virus in explant cultures of ipsilateral and contralateral trigeminal ganglia from latently infected mice. The use of a gel formulation containing combinations of foscarnet and SLS could represent an attractive approach for the treatment of herpetic mucocutaneous infections. PMID:11257012
Seto, Jennifer E.; Polat, Baris E.; Lopez, Renata F.V.; Blankschtein, Daniel; Langer, Robert
2010-01-01
The simultaneous application of ultrasound and the surfactant sodium lauryl sulfate (referred to as US/SLS) to skin enhances transdermal drug delivery (TDD) in a synergistic mechanical and chemical manner. Since full-thickness skin (FTS) and split-thickness skin (STS) differ in mechanical strength, US/SLS treatment may have different effects on their transdermal transport pathways. Therefore, we evaluated STS as an alternative to the well-established US/SLS-treated FTS model for TDD studies of hydrophilic permeants. We utilized the aqueous porous pathway model to compare the effects of US/SLS treatment on the skin permeability and the pore radius of pig and human FTS and STS over a range of skin electrical resistivity values. Our findings indicate that the US/SLS-treated pig skin models exhibit similar permeabilities and pore radii, but the human skin models do not. Furthermore, the US/SLS-enhanced delivery of gold nanoparticles and quantum dots (two model hydrophilic macromolecules) is greater through pig STS than through pig FTS, due to the presence of less dermis that acts as an artificial barrier to macromolecules. In spite of greater variability in correlations between STS permeability and resistivity, our findings strongly suggest the use of 700-μm-thick pig STS to investigate the in vitro US/SLS-enhanced delivery of hydrophilic macromolecules. PMID:20346994
Törmä, Hans; Berne, Berit
2009-12-01
Detergents irritate skin and affect skin barrier homeostasis. In this study, healthy skin was exposed to 1% sodium lauryl sulphate (SLS) in water for 24 h. Biopsies were taken 6 h to 8 days post exposure. Lipid patterns were stained in situ and real-time polymerase chain reaction (PCR) was used to examine mRNA expression of enzymes synthesizing barrier lipids, peroxisome proliferator-activated receptors (PPAR) and lipoxygenases. The lipid pattern was disorganized from 6 h to 3 days after SLS exposure. Concomitant changes in mRNA expression included: (i) reduction, followed by induction, of ceramide-generating beta-glucocerebrosidase, (ii) increase on day 1 of two other enzymes for ceramide biosynthesis and (iii) persistent reduction of acetyl-CoA carboxylase-B, a key enzyme in fatty acid synthesis. Surprisingly, the rate-limiting enzyme in cholesterol synthesis, HMG-CoA reductase, was unaltered. Among putative regulators of barrier lipids synthesis, PPARalpha and PPARgamma exhibited reduced mRNA expression, while PPARbeta/delta and LXRbeta were unaltered. Epidermal lipoxygenase-3, which may generate PPARalpha agonists, exhibited reduced expression. In conclusion, SLS induces reorganization of lipids in the stratum corneum, which play a role in detergents' destruction of the barrier. The changes in mRNA expression of enzymes involved in synthesizing barrier lipids are probably important for the restoration of the barrier.
Oral fluoride levels 1 h after use of a sodium fluoride rinse: effect of sodium lauryl sulfate.
Vogel, Gerald L; Schumacher, Gary E; Chow, Laurence C; Tenuta, Livia M A
2015-01-01
Increasing the concentration of free fluoride in oral fluids is an important goal in the use of topical fluoride agents. Although sodium lauryl sulfate (SLS) is a common dentifrice ingredient, the influence of this ion on plaque fluid and salivary fluid fluoride has not been examined. The purpose of this study was to investigate the effect of SLS on these parameters and to examine the effect of this ion on total (or whole) plaque fluoride, an important source of plaque fluid fluoride after a sufficient interval following fluoride administration, and on total salivary fluoride, a parameter often used as a surrogate measure of salivary fluid fluoride. Ten subjects accumulated plaque for 48 h before rinsing with a 12 mmol/l NaF (228 µg/g F) rinse containing or not containing 0.5% (w/w) SLS. SLS had no statistically significant effect on total plaque and total saliva fluoride but significantly increased salivary fluid and plaque fluid fluoride (by 147 and 205%, respectively). These results suggest that the nonfluoride components of topical agents can be manipulated to improve the fluoride release characteristics from oral fluoride reservoirs and that statistically significant change may be observed in plaque fluid and salivary fluid fluoride concentrations that may not be observed in total plaque and total saliva fluoride concentrations.
Lopez, Renata F V; Seto, Jennifer E; Blankschtein, Daniel; Langer, Robert
2011-01-01
The potential of rigid nanoparticles to serve as transdermal drug carriers can be greatly enhanced by improving their skin penetration. Therefore, the simultaneous application of ultrasound and sodium lauryl sulfate (referred to as US/SLS) was evaluated as a skin pre-treatment method for enhancing the passive transdermal delivery of nanoparticles. We utilized inductively coupled plasma mass spectrometry and an improved application of confocal microscopy to compare the delivery of 10- and 20-nm cationic, neutral, and anionic quantum dots (QDs) into US/SLS-treated and untreated pig split-thickness skin. Our findings include: (a) ∼0.01% of the QDs penetrate the dermis of untreated skin (which we quantify for the first time), (b) the QDs fully permeate US/SLS-treated skin, (c) the two cationic QDs studied exhibit different extents of skin penetration and dermal clearance, and (d) the QD skin penetration is heterogeneous. We discuss routes of nanoparticle skin penetration and the application of the methods described herein to address conflicting literature reports on nanoparticle skin penetration. We conclude that US/SLS treatment significantly enhances QD transdermal penetration by 500-1300%. Our findings suggest that an optimum surface charge exists for nanoparticle skin penetration, and motivate the application of nanoparticle carriers to US/SLS-treated skin for enhanced transdermal drug delivery. Copyright © 2010 Elsevier Ltd. All rights reserved.
Kushner, Joseph; Blankschtein, Daniel; Langer, Robert
2008-02-01
The porosity (epsilon), the tortuosity (tau), and the hindrance factor (H) of the aqueous pore channels located in the localized transport regions (LTRs) and the non-LTRs formed in skin treated simultaneously with low-frequency ultrasound (US) and the surfactant sodium lauryl sulfate (SLS), were evaluated for the delivery of four hydrophilic permeants (urea, mannitol, raffinose, and inulin) by analyzing dual-radiolabeled diffusion masking experiments for three different idealized cases of the aqueous pore pathway hypothesis. When epsilon and tau were assumed to be independent of the permeant radius, H was found to be statistically larger in the LTRs than in the non-LTRs. When a distribution of pore radii was assumed to exist in the skin, no statistical differences in epsilon, tau, and H were observed due to the large variation in the pore radii distribution shape parameter (3 A to infinity). When infinitely large aqueous pores were assumed to exist in the skin, epsilon was found to be 3-8-fold greater in the LTRs than in the non-LTRs, while little difference was observed in the LTRs and in the non-LTRs for tau. This last result suggests that the efficacy of US/SLS treatment may be enhanced by increasing the porosity of the non-LTRs.
Delivery of paclitaxel across cellular barriers using a dendrimer-based nanocarrier.
Teow, Huey Minn; Zhou, Zhengyuan; Najlah, Mohammad; Yusof, Siti R; Abbott, N Joan; D'Emanuele, Antony
2013-01-30
The aim of this study was to investigate the ability of a third-generation (G3) polyamidoamine (PAMAM) dendrimer-based carrier to enhance the permeability of paclitaxel (pac) and to overcome cellular barriers. G3 dendrimers were surface modified with lauryl chains (L) and conjugated with paclitaxel (pac) via a glutaric anhydride (glu) linker, followed by labeling with FITC. Biological evaluation of the dendrimer and conjugates was conducted using the human colon adenocarcinoma cell line (Caco-2) and primary cultured porcine brain endothelial cells (PBECs). LDH assay was used to evaluate the cytotoxicity of the dendrimer and conjugates. Cytotoxicity studies showed that the conjugation of lauryl chains and paclitaxel on G3 dendrimer significantly (p<0.05) increased the cytotoxicity against both cell types. Permeability studies of dendrimer-drug conjugates demonstrated an increase in the apparent permeability coefficient (P(app)) in both apical to basolateral A→B and basolateral to apical B→A directions across both cell monolayers compared to unmodified G3 and free drug. The B→A P(app) of paclitaxel was significantly (p<0.05) higher than the A→B P(app), indicating active function of P-gp efflux transporter system in both cell models. L6-G3-glu-pac conjugate had approximately 12-fold greater permeability across both cell monolayers than that of paclitaxel alone. Copyright © 2012 Elsevier B.V. All rights reserved.