Effects of Pluronic F68 on Manganese Peroxidase Production by Pelletized <Emphasis Type="Italic">Phanerochaete chrysosporium</Emphasis>

In this study, a new process was developed for manganese peroxidase (MnP) production by Phanerochaete chrysosporium under an agitated and aerated cultivation condition. It was found that change of the inoculum from spore suspension to pellets resulted in enhanced MnP production of 200 U/L in rotated shake flasks. Several additives, including Pluronic F68, Tween 80, and PEG8000, significantly increased the enzyme production. With an optimal concentration in 125 mL flasks, Pluronic F68 increased MnP productivity by 180%. Moreover, successful enzyme production was achieved in a 5-L fermentor at an agitation speed of 300 rpm with the addition of 0.1% Pluronic F68.     

Determination of Required HLB of Capryol 90

The required hydrophilic-lipophilic balance (HLB) of an oily substance indicates the HLB of the surfactants required to prepare a stable emulsion using the oil. This study utilizes empirical method to calculate required HLB (RHLB) of Capryol 90 using surfactant blends (Span 20, Tween 20, vitamin E TPGS, Pluronic F68, Span 60, and Tween 80). The methods used were assessment of degree of creaming after centrifugation and after shelf storage for 28 days at room temperature, turbidimetric method, accelerated stability study, and droplet size analysis. The droplet size was found to be in the range of 15 to 2 µm and v/v% separation after centrifugation was found to be 0–82%. The RHLB for Capryol 90 was found to be 15. The effect of various surfactant blends was investigated. Results revealed that a blend of tocopherol polyethylene glycol succinate (TPGS) and Pluronic F68 gave the most stable emulsion for Capryol 90.     

Evaporative light scattering detection based HPLC method for the determination of polysorbate 80 in therapeutic protein formulations

An evaporative light scattering detection (ELSD) based high-performance liquid chromatography (HPLC) method is developed for the determination of polysorbate 80 (tween 80) in therapeutic protein formulations. The method is simple and overcomes the difficulties associated with specificity and sensitivity. The method is suitable for the quantitation of polysorbate 80 in the usual formulation range (0.01-0.1%) as well as in trace amounts ≥13 μg/mL. The analysis is based on the removal of protein first by solid-phase extraction using Oasis HLB cartridges followed by HPLC analysis using Inertsil ODS-3 C 18 column (4.6×150 mm, 5 μm) using reversed-phase conditions. The detector response changes exponentially with an increase in polysorbate concentration. A very good linear fit of log ELSD response against log polysorbate 80 concentration is observed. The specificity, sensitivity, precision, and accuracy of the method are suitable for the quantitation of polysorbate 80 in protein formulations.     

Comparative effects of different cosurfactants on sterile prednisolone acetate ocular submicron emulsions stability and release

Pluronic F68 is a nonionic, thermogelling block copolymer showing a high dehydration resistance during autoclaving due to its high cloud point (>100 °C). Tween 80 (with cloud point of 72.5 °C), is a polyoxyethylene-based cosurfactant, susceptible to temperature because of a decrease in its solubility by temperature increase. This study was done to explore whether or not, when compared with Tween 80, Pluronic F68 could be used blindly as a suitable cosurfactant for the preparation of terminally sterilized ocular submicron emulsions containing a lipid soluble drug, prednisolone acetate (PA). Various oils of variable viscosities were also tried. The results proved that no prediction can be made based on previously known physico-chemical properties alone and that emulsion stability depends on the contribution of the various emulsion components including: oil, surfactant and cosurfactant, in addition to the drug properties.     

Cloud point analysis: Influence of additives on polysorbate

The solution properties of nonionic surfactants are significantly diverse from those of ionic surfactants. Additives to nonionic surfactant solution do change the cloud point (CP). In this article, we report the CP data of polysorbate 20 (tween-20) and polysorbate 80 (tween-80), nonionic surfactants, in the presence of various additives and also focus on their characteristics. It is observed that the micellization tendency of the polysorbates changes in the presence of different additives. The addition of different variants of salts decreases the CP of polysorbates solutions. Furthermore, the higher the valency of the cation, the lesser is the depression in the CP of the polysorbates. Overall monovalent, di-valent and a mixture of di-valent salts have large affinity to alter the values of CP of polysorbates, because of their effect on the water structure and their hydrophilicity. An effort has been made to understand the influence of various combinations of salts on polysorbates.     

用双表面活性剂为共模板合成中孔分子筛MCM-48

利用水热法以非离子表面活性剂聚乙二醇辛基苯基醚和阳离子表面活性剂十六烷基三甲基溴化铵为共模板合成了中孔分子筛MCM-48.实验中发现利用较强的范德华力和氢键,聚乙二醇辛基苯基醚可在很大程度上降低合成MCM-48所需阳离子表面活性剂的用量,且利于制备有序性好、骨架聚合度高、稳定性好的MCM-48.通过调节聚乙二醇辛基苯基醚与十六烷基三甲基溴化铵的比例,可得到不同物相结构的分子筛.     

Synthesis and evaluation of cationic and cationogenic polymeric sorbents for removing surfactants from aqueous solutions

Polymers based on 2‐dimethylaminoethyl methacrylate (DMAEMA) crossslinked with ethylene glycol dimethacrylate (EGDMA) or N,N′‐methylenebisacrylamide (MBAA) have been prepared by solution‐suspension polymerization. Polymers containing ammonium groups were synthesized by quaternization of aminofunctional polymers obtained with ethyl or dodecyl bromide or by the polymerization of respective quaternized monomers. Influence of the content of DMAEMA in the polymers, nominal degree of crosslinking, length of alkyl substituent in quaternary ammonium groups as well as particle size on the sorption of anionic and nonionic surfactants from aqueous solutions has been studied.     

Interactions between nonionic Triton X surfactants and cholesterol-containing phosphatidylcholine liposomes

Solubilization kinetics experiments were developed to study the effects of the polyethylene glycol chain length of Triton X surfactants on their interactions with the cholesterol-containing phosphatidylcholine vesicles. An empirical liposome stability ratio was used to describe the vesicle solubilization process. The effectiveness of Triton X surfactants in solubilizing vesicles decreases with increasing polyethylene glycol chain length of surfactants. It was also shown that vesicles containing the intercalated surfactant molecules with the largest number of ethylene glycol units per molecule exhibited the exceedingly retarded solubilization behavior. Independent experiments based on a thermodynamic approach provide supporting evidence for the conclusions obtained from solubilization kinetics experiments.     

Micellization and Adsorption Parameters of Nonionic Polymeric Surfactants from Poly(ethylene terephthalate) Waste

Poly (ethylene terephthalate), PET, waste was recycled to oligomers in the presence of triethanolamine and manganese acetate as a catalyst. The produced oligomers were reacted with stearic acid and polyethylene glycol having different molecular weights 400, 1000, and 4000 to produce nonionic polymeric surfactants having different hydrophile‐hydrophobe balances (HLB). The surface tension, critical micelle concentration (CMC) and surface activities were determined at different temperatures. Surface parameters such as, surface excess concentration Γ_max, the area per molecule at interface A_min and the effectiveness of surface tension reduction (Π_CMC) were determined from the adsorption isotherms of the prepared surfactants. Some thermodynamic data for the adsorption process are calculated and discussed.     

Evaluation of Nonionic Block Polymer Surfactants in Maize Root Proteome Extraction within Water�COrganic Solvent Phases

In the present work, six nonionic block copolymer surfactants consisting of poly(ethylene glycol) (PEG), polyethylene (PE), and poly(propylene glycol) (PPG) were exploited to extract total proteins from maize (Zea mays L.) roots within a water?Corganic solvent system. After the treatment, proteins were partitioned into aqueous phase, interphase, and organic phase. The total yield was increased by up to 30% after adding PE-PEG block polymer surfactant compared with control. Two-dimensional electrophoresis (2-DE) was further used to evaluate proteins in water phase and interphase; the results revealed that the spot numbers and density were all improved, and well-focused electrophoretic patterns were achieved with higher density and without excess Joule heating problem after adding nonionic block polymer surfactants. Among the six investigated block polymers, PE-PEG extracted the largest amount of proteins.     

Surface and bulk properties of aqueous binary mixtures of Pluronic F68 and low-molecular-weight cationic surfactants: 1. Surface tension and association in aqueous solutions

Surface tension of aqueous binary mixtures of Pluronic F68 and low-molecular-weight cationic surfactants is measured. The synergistic a decrease in surface tension is revealed. It is shown that this effect is controlled by the chemical structure of cationic surfactants and determined by an increased (compared to the bulk) content of Pluronic F68 in the surface layer, which is formed due to the adsorption of the individual molecules of mixture components.     

Surface dilatational elasticity of poly(oxy ethylene)-based surfactants by oscillation and relaxation measurements of sessile bubbles

Surface dilatational elasticities and viscosities have been measured by means of the axisymmetric bubble shape method. Two different techniques using sinusoidal oscillations and step relaxations have been used, and the results are treated by means of the bulk/surface diffusional exchange model. Three different nonionic surfactants based on poly(oxy ethylene) as the hydrophilic group have been used: one simple surfactant, Brij 35, and two block copolymers, Pluronic F68 and P9400. Step relaxation and oscillation give mostly the same limiting surface dilatational elasticities, but step relaxation is a more model-dependent method. In the cases where the bulk/surface diffusion model is correct, the two methods give the same results, but otherwise step relaxation gives average values of the limiting elasticity E0 and the typical relaxation frequency omega0. Limiting elasticities up to ca. 25 mN m(-1)have been found for these substances. The surface/bulk diffusion model describes quite well the two relatively hydrophilic substances Brij 35 and F68, especially at low concentrations, but less so for the more hydrophobic P9400. The surface dilatational elasticity as a function of the surface pressure of the surface-active polymers goes through at least one maximum as a result of surface conformational changes.     

Analysis of some commercial polysorbate formulations using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

Analyses of polysorbate formulations (Tween 20, Tween 40, Tween 60, and Tween 80) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) reveal a complex mixture of oligomers that include polyethylene glycols, polyethylene glycol esters, isosorbide polyethoxylates, sorbitan polyethoxylates, polysorbate monoesters, polysorbate diesters, and sorbitol polyethoxylate esters. The MALDI-TOF mass spectra for these formulations show the presence of sodiated molecules in which the major signals are attributed to the presence of polyethylene glycols, isosorbide polyethoxylates, and sorbitan polyethoxylates. Additionally, the complexity of the spectra was correlated to the constituent fatty acid moieties in the polysorbate formulations. Thus Tween 20 showed the presence of polysorbate monolaurates, polysorbate monomyristates, and polysorbate monopalmitates. Tween 40 contained polysorbate mono- and dipalmitates. Tween 60 contained polysorbate monopalmitates and polysorbate monostearates. For the Tween 80, mass assignment for polysorbate monooleates and polysorbate dioleates was equivocal, because both of these oligomeric series have the same molecular weight as the sorbitan polyethoxylates, and thus the Tween 80 MALDI-TOF spectrum appeared to be the least complicated of the four commercial polysorbate formulations.     

Application of New Modified Poly(ethylene Oxide)-Block-Poly(propylene oxide)-Block-Poly(ethylene oxide) Copolymers as Demulsifier for Petroleum Crude Oil Emulsion

Water soluble nonionic amphiphilic block copolymers based on hydrophilic poly(ethylene glycol) (PEG) and hydrophobic poly(propylene glycol) (PPG) were prepared. Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) copolymers, PEG-PPG-PEG, were prepared in the normal condition. The chemical composition and molecular weights of the prepared copolymers were determined from ¹H NMR and GPC techniques. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The prepared nonionic surfactants were evaluated as demulsifiers for water in crude-oil emulsions that were pronounced at different ratios of crude oil: water at 318 K and 333 K. The experimental results showed that the dehydration rate of the prepared demulsifiers reached 100% based on demulsifier chemical compositions and concentrations.     

Universal Janus Filters for the Rapid Separation of Oil from Emulsions Stabilized by Ionic or Nonionic Surfactants

Existing Janus filters cannot separate oil from emulsions stabilized by nonionic surfactants. Reported herein are universal Janus filters that separate oil from emulsions stabilized by not only ionic but also nonionic surfactants. To prepare such a filter, poly(dimethyl siloxane) (PDMS) is grafted onto one side of a fabric. The other side is then grafted with a copolymer polysoap bearing pendant oligo(ethylene glycol) monolaurate (EL) chains. Upon contact with an emulsion, the grafted polysoap competes with free surfactants, ionic or nonionic, for adsorption onto the emulsified droplets, drawing them to the surfaces of the fabric fibers, and causes them to coalesce locally. The coalesced oil then migrates to the PDMS‐coated side of the fabric and selectively permeates it. These novel filters possess enhanced versatility and showcase a new application for polysoaps.     

Oxidation of nonionic surfactants with molecular oxygen

Kinetic regularities are studied for the air oxidation of surfactants that are widely used in the food industry, such as natural phosphatidylcholine (egg lecithin, PC) and synthetic nonionic surfactants Triton X-100 (ТХ-100), Tween 65, and Pluronic F68. Azobis(amidinopropane)-dichloride-initiated oxidation of these surfactants in an aqueous medium at 37°C develops via the chain free-radical mechanism. The chain length is equal to 5–10 units, depending on the initiator-to-surfactant concentration ratio. The rate of surfactant oxidation in an aqueous medium is proportional to the rate of radical initiation. At the same mass concentrations of the reagents, the rate of PC oxidation is several times higher than the oxidation rates of the other surfactants. The addition of TX-100 to PC liposomes decelerates the oxidation; i.e., TX-100 plays the role of an antioxidant for PC. The superposition of the oxidation rates of individual and mixed PC and TX-100 with the sizes of the microaggregates formed in their aqueous solutions shows that the antioxidation action of TX-100 is realized via the formation of a protective layer composed of its ethylene oxide groups, which shields PC liposomes from radicals, which are initiated in the bulk of an aqueous phase due to the decomposition of azobis(amidinopropane) dichloride.     

Gas chromatography with mass spectrometry for the quantification of ethylene glycol ethers in different household cleaning products

A rapid and simple procedure is reported for the determination of six ethylene glycol ethers in cleaning products and detergents using gas chromatography with mass spectrometry. The analytes were extracted from 2.0 g samples in acetonitrile (3 mL) and the extract was submitted to a clean‐up step by QuEChERS method, using a mixture containing 0.3 g magnesium sulfate, 0.15 g primary/secondary amine, and 0.05 g C₁₈. The clean acetonitrile extract (1 μL) was injected into the chromatographic system. No matrix effect was observed, so the quantification of the samples was carried out against external standards. Detection limits were in the range 3.0–27 ng/g for the six ethylene glycol ethers. The recoveries obtained, using the optimized procedure, were in the 89.4–118% range, with relative standard deviations lower than 14%. Twenty‐three different household cleaning products, including glass cleaner, degreaser, floor, softeners, and clothes and dishwashing detergents, were analyzed. Large interindividual variations were observed between samples and compounds.     

Formation of Pegylated polyurethane and Lysine-coated polyurea nanoparticles obtained from O/W nano-emulsions

The present work describes the formation of Pegylated polyurethane and Lysine-coated polyurea nanoparticles obtained from O/W nano-emulsions via an interfacial polycondensation process in the aqueous solution/polysorbate 80/diisocyanate/medium chain triglyceride systems. The initial nano-emulsions were prepared using the phase inversion composition (PIC) method. Dynamic light scattering studies revealed the changes in the particle size occurring during the process of nanoparticle formation. Well-defined polymeric nanoparticles with a small particle diameter (below 80 nm) and low polydispersity index were obtained using a highly hydrophilic component (polyethylene glycol or lysine) and an aliphatic diisocyante monomer. FT-IR and AFM studies showed that the polymeric matrix of nanoparticles was built by copolymers derived from reaction between the diisocyanate and the hydroxyl groups of both nonionic surfactant and the highly hydrophilic component. Pegylated-polyurethane and lysine-coated polyurea nanoparticles designed in this study are promising tools for future applications in biomedical sciences.     

The Effects of Salts and Ionic Surfactants on the Micellar Structure of Tri‐Block Copolymer PEO‐PPO‐PEO in Aqueous Solution

The micelles of two poly(ethylene oxide)‐poly(propylene oxide)‐poly(ethylene oxide) (PEO‐PPO‐PEO) block copolymers, P123 and F127 (same mol wt of PPO but different % PEO) in aqueous solution in the absence and presence of salts as well as ionic surfactants were mainly examined by dynamic light scattering (DLS). The study is further supported by cloud point and viscosity measurements. The change in cloud point (CP), as well as the size of micelles in aqueous solution in presence of salts obeys the Hofmeister lyotropic series. Addition of both cationic cetylpyridinium chloride (CPC) and anionic sodium dodecylsulfate (SDS) surfactants in the aqueous solution of P123 show initial decrease of micellar size from 20 nm to nearly 7 nm and then increasing with a double relaxation mode, further in the presence of NaCl this double relaxation mode vanishes. The effect of surfactant on F127, which has much bigger hydrophilic part is different than P123 and have no double relaxation. The relaxation time distributions is obtained using the Laplace inversion routine REPES. Two relaxation modes for P123 are explained on the bases of Pluronic rich mixed micelles containing ionic surfactants and the other smaller, predominantly surfactant rich micelles domains.     

Simultaneous separation of nonionic surfactants and polyethylene glycols by reversed phase high performance liquid chromatography

Summary The simultaneous separation of polyethylene glycol and its derivatives such as the lauryl alcohol and lauric acid ethoxylate oligomers was carried out by reversed phase high performance liquid chromatography. Branched fluorinated silica gel columns combined with evaporative light scattering detection were used for the characterization of nonionic surfactants. Lauryl alcohol ethoxylate oligomers were separated at 10°C with an isocratic eluent according to ethoxylate number and the retention time of the oligomers decreases with increasing ethoxylate number. The Van’t Hoff plots of retention factor of lauryl alcohol ethoxylate gave a complex cure, which is anomalous behavior for reversed phase high performance liquid chromatography. The anomalous Van’t Hoff plots were explained by a partial conformational change from polar to less polar conformers with increasing temperature. The most significant features for the analysis of the lauryl alcohol ethoxylate were the use of acetonitrile as mobile phase and operating temperature. The polyethylene glycol was separated according to ethoxylate number and the retention time of oligomers increased with increasing ethoxylate number. The Van’t Hoff plots of retention factor of polyethylene glycol had negative slopes. It was presumed that the polar conformation of the ethylene oxide chain decreased with increasing temperature. The lauryl alcohol ethoxylate and polyethylene glycol were separated simultaneously in gradient elution as a result of the conformational change of the ethylene oxide chain. As a practical example, lauric acid ethoxylate simultaneously separated into free polyethylene glycol, ethoxylate monolaurate and ethoxylate dilaurate in gradient elution.