Polyethylene Glycol Monolaurate Research Articles

Pressure-volume-temperature properties for binary oligomeric solutions of anisole with polyethylene glycol mono-laurate or polyethylene glycol mono-4-nonylphenyl ether at pressures up to 50MPa

Experimental of P-V-T properties are measured for two binary systems containing anisole and one of oligomeric materials (polyethylene glycol mono-laurate, PEGML, and polyethylene glycol mono-4-nonylphenyl ether, PEGNPE) at temperatures ranging from 298.15K to 348.15K and pressures up to 50 MPa. Over the whole range of experimental conditions, the excess volumes of anisole + PEGML are negative (chemical-interaction dominant) and those of anisole + PEGNPE are positive (physical-interaction dominant). The Tait equation and the Redlich-Kister type model quantitatively represents the pressure-effect on the densities and the composition-effect on the excess volumes of the investigated systems, respectively. The Flory-Orwoll-Vrij (FOV) and the Schotte equations of state with or without using one binary interaction parameter calculate the specific volumes to RMSDs no greater than 0.04% and 0.11%, respectively.

Pressure-Volume-Temperature Properties for Binary Oligomeric Solutions of Anisole with Polyethylene Glycol Mono-Laurate or Polyethylene Glycol Mono-4-Nonylphenyl Ether at Pressures Up to 50 Mpa

Pressure-Volume-Temperature Properties for Binary Oligomeric Solutions of Anisole with Polyethylene Glycol Mono-Laurate or Polyethylene Glycol Mono-4-Nonylphenyl Ether at Pressures Up to 50 Mpa

Viscosities of polyethylene glycol monolaurate in alcohol solvents from non-equilibrium molecular dynamics (NEMD) simulation

Non-equilibrium molecular dynamic (NEMD) simulation was carried out to calculate the shear viscosities based on the periodic perturbation method. Six binary systems composed of polyethylene glycol monolaurate (PEGML) in aliphatic alcohols were studied, namely PEGML with methanol, ethanol, 2-propanol, 2-butanol, tert-butanol, and 1-pentanol, respectively. The simulated systems were subjected to an external shear-stress acceleration field which induces a velocity gradient of the liquid, and the shear viscosity was further determined from the resulting velocity. Different values of shear-stress acceleration in the range of (0.005 to 0.08) nm ps2 were used to perform an independent simulation. The viscosity was further calculated for each of shear-stress acceleration rate and then extrapolated to obtain the zero-shear rate viscosity. It is found that the shear viscosity follows the order of PEGML + tert-butanol > PEGML + 1-pentanol > PEGML + 2-butanol > PEGML + 2-propanol > PEGML + ethanol > PEGML + methanol, respectively.

Insight into structural properties of polyethylene glycol monolaurate in water and alcohols from molecular dynamics studies.

By means of molecular dynamics (MD) simulations, we explored the structural properties of polyethylene glycol monolaurate (PEGML) in water and in various aliphatic alcohols (methanol, ethanol, 2-propanol, 2-butanol, tert-butanol, and 1-pentanol). The PEGML and the alcohols were simulated using the optimized potentials for liquid simulations, all-atom (OPLS-AA) force field and water using the extended simple point charge (SPC/E) model. From the isothermal-isobaric (NPT, constant number of particles, constant pressure, and constant temperature) ensemble, we extracted the densities from the simulations and compared them with those from experimental results in order to confirm the validity of the selected force fields. The densities from MD simulations are in good agreement with the experimental values. To gain more insight into the nature of interactions between the PEGML and the solvent molecules, we analyzed the hydrogen-bonds, the electrostatic (Coulomb) interactions, and the van der Waals (Lennard-Jones) interaction energies extracted from MD simulations. The results were further strengthened by computing the solvation free energy by employing the free energy perturbation (FEP) approach. In this method, the free energy difference was computed by using the Bennet Acceptance Ratio (BAR) method. Moreover, the radial distribution functions were analyzed in order to gain more understanding of the solution behavior at the molecular level.

Pressure-volume-temperature properties for binary oligomeric blends of polyethylene glycol mono-laurate with polyethylene glycol mono-4-octylphenyl ether or polyethylene glycol mono-4-nonylphenyl ether at pressures up to 50 MPa

Densities are measured for two binary systems of oligomeric blends, polyethylene glycol mono-4-octylphenyl ether) (PEGOPE) + polyethylene glycol mono-laurate (PEGML) and polyethylene glycol mono-4-nonylphenyl ether (PEGNPE) + PEGML, at temperatures from 298.15 K to 348.15 K and pressures up to 50 MPa. The excess volumes are negative for these two binary systems over the majority of composition range, except for the regions near pure components, in which the values may change into positive. Tait equation represents accurately for the pressure-effect on the liquid densities. Additionally, a generalized equation with two characteristic parameters correlates well the P-V-T data over the entire experimental conditions for each binary system. Those P-V-T data are also correlated satisfactorily with the Flory-Orwoll-Vrij (FOV) and the Schotte equations of state with one binary interaction parameter for each oligomeric blend system.

Highly permeable forward osmosis (FO) membranes for high osmotic pressure but viscous draw solutes

Recently, a wide range of large size draw solutes have been developed and employed in forward osmosis (FO) processes with the advantages of high water flux, minimum reverse flux and easy recovery. However, the high viscosity of these draw solutes tends to suffer from severer internal concentration polarization (ICP) and internal fouling within the sublayers. To solve these problems, a dual selective flat sheet membrane has been designed in this study in order to prevent the viscous draw solutes from entering the porous support layer and minimize the ICP effects. It consists of three layers: a top thin polyamide layer synthesized from interfacial polymerization, a middle porous cellulose ester layer, and another bottom thin polyamide layer. The dual selective thin film composite (TFC) membrane has a reasonably high water flux of 34.5LMH and a low salt reverse flux of 3.5gMH using DI water and 1M NaCl as the feed and draw solutions respectively under the FO mode. Comparing to single selective TFC membranes, the dual selective membrane significantly mitigated ICP effects and reduced fouling propensity using viscous draw solutes such as sucrose, ferric citric acid complex (Fe–CA) and polyethylene glycol monolaurate (PEG 640ML) as draw solutes. The newly developed dual selective membrane has great potential to maximize the effectiveness of viscous draw solutes in various FO processes.

Transdermal delivery of flurbiprofen from surfactant-based vesicles: Particle characterization and the effect of water on in vitro transport

Flurbiprofen loaded rigid and elastic vesicles comprising the bilayer-forming surfactant sucrose-ester laurate were prepared by the film rehydration and extrusion method. The charge-inducing agent sodium dodecyl sulfate, and the micelle-forming surfactants, sorbitan monolaurate, polyethylene glycol monolaurate, and polysorbate 20, were used to enhance elasticity. Vesicle formulations were evaluated for size, zeta potential, (1)H and (19)F nuclear magnetic resonance (NMR) spectra, and in vitro skin permeation across Yucatan micropig (YMP) skin. Vesicle formulations were stable for 2 weeks and their mean sizes were 95-135 nm. NMR spectroscopy showed that flurbiprofen molecular mobility was restricted by interaction with vesicle components because of entrapment in vesicle bilayers. Moreover, sorbitan monolaurate-containing vesicles strongly retained flurbiprofen molecules. After non-occlusive application to YMP skin, flurbiprofen transport from all vesicle formulations was superior to that of flurbiprofen alone and remarkably decreased after water vaporization. Polarization microscopy and small-angle X-ray diffraction analysis showed that the vesicle formulation was transferred to liquid crystalline state. Suppression of vesicle transition to the liquid crystalline state was observed with applications of both large quantities and diluted samples. The presence of water in the formulations was associated with maintenance of the vesicle structure and greater flurbiprofen transport across YMP skin.

ChemInform Abstract: Zero Thermal Expansion Fluid and Oriented Film Based on a Bistable Metal‐Cyanide Polymer.

AbstractPlate‐shaped microcrystals of Rb0.97Mn [Fe(CN)6]0.99·0.3H2O are synthesized by mixing an aqueous solution containing polyethylene glycol monolaurate, MnCl2, and RbCl with an aqueous solution of polyethylene glycol monolaurate, K3[Fe(CN)6], and RbCl.

Zero Thermal Expansion Fluid and Oriented Film Based on a Bistable Metal-Cyanide Polymer

A zero thermal expansion (ZTE) material based on plate-shaped rubidium manganese hexacyanoferrate, Rb0.97Mn[Fe(CN)6]0.99·0.3H2O, is prepared using a polyethylene glycol monolaurate (PEGM) surfactant matrix. The prepared microcrystals show a charge transfer induced phase transition between the cubic MnII–NC–FeIII and tetragonal MnIII–NC–FeII phases. The MnIII–NC–FeII phase exhibits a small negative thermal expansion (NTE) along the aLT and cLT axes with a thermal expansion coefficient of α(aLT) = −1.40 ± 0.12 × 10–6 K–1 and α(cLT) = −0.17 ± 0.13 × 10–6 K–1 over a wide temperature range of 15 K – 300 K. Such small |α| materials are classified as ZTE materials. The far-infrared spectra show that NTE originates from the transverse modes δ(Fe–C≡N–Mn)of the transverse translational mode around 304 cm–1, and transverse librational modes at 253 and 503 cm–1, which are assigned according to first principle calculations. Molecular orbital calculations indicate that ZTE and the charge transfer phase transition both ...

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

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

Hydration of an amphiphilic excipient, Gelucire ® 44/14

The incorporation of drugs into Gelucires has been reported to increase the dissolution rate of poorly soluble drugs, often leading to improved drug bioavailability. In pharmaceutical applications, it is important to know how the excipient interacts with the drug, and how the mixture behaves during manufacturing, storage as well as during administration. The uptake of water by an amphiphilic excipient, Gelucire ® 44/14, has been investigated in two ways: storage in humid air and addition of liquid water. During exposure to humid air, the uptake goes in stages that correspond to the dissolution of the components of the excipient, starting with the most hydrophilic ones: glycerol, then polyethylene glycol (PEG), PEG esters (PEG monolaurate and PEG dilaurate), and finally glycerides (trilaurin). At each stage, the remaining crystals are in equilibrium with an interstitial solution made of water and the dissolved components. In this range of hydrations, the total uptake is close to the sum of the equilibrium hydrations of the components. In the pharmaceutical formulation, the active ingredient could dissolve in the liquid phase. At larger hydrations, obtained through addition of liquid water, the state of Gelucire ® 44/14 differs from those of its components. Gelucire ® 44/14 forms a lamellar phase and this phase melts at 30 °C whereas the pure PEG esters form hexagonal and cubic mesophases. The cubic mesophases do not melt until the temperature exceeds 40 °C. At body temperature, all crystals in Gelucire ® 44/14 melt to an isotropic fluid as soon as the total water content exceeds 5%. Therefore the formulation of amphiphilic excipients can be optimized to avoid the formation of mesophases that impede dissolution of the excipient at body temperature.

Ostwald Ripening of Alkane Emulsions Stabilized by Polyethylene Glycol Monolaurate

The Ostwald ripening of alkane in water emulsions stabilized by the surfactant poly(ethylene glycol) monolaurate (PEM) was investigated. Surprisingly the measured ripening rates were significantly below the rate which can be predicted by the Lifshitz−Slyozov−Wagner (LSW) theory and decreased in the presence of surfactant micelles. A possible explanation of the effect of these micelles is that they withdraw oil from the continuous phase and hence slow the transport of oil from smaller to larger droplets.

Lecithin organogels containing poly(ethylene glycol) monolaurate

The effect of added poly(ethylene glycol) monolaurate (PEGML) on the formation and properties of lecithin organogels composed of polymer-like micelles was studied by the methods of dynamic rheology and the Fourier transform IR spectroscopy. It was established that the addition of even small amounts of PEGML causes a significant decrease in viscosity, whereas the elastic properties of organogels remained almost unchanged. The analysis of the scaling dependences indicated that the formation mechanism of polymer-like lecithin micelles remained also unchanged. Spectral studies revealed that the PEGML molecules affect intermolecular hydrogen bonding during their incorporation into micelles, thus stabilizing micellar structure. This effect is caused by the partial dehydration of the lecithin polar region. This leads to a decrease in the number of hydrogen bonds or their weakening and, as a result, to the disintegration of polymer-like lecithin micelles into shorter micellar aggregates.

Polymerization of methacrylic acid in the presence of two competing matrices

The radical of methacrylic acid in water in the presence of matrices i.e., poly-N-vinylpyrrolidone of different MM, polyethylene glycol monolaurate and their mixtures is studied. Under some conditions the transition of the polymethacrylic acid molecules during growth from the strong, but short poly-N-vinylpyrrolidone matrix onto the weaker matrix, i.e. polyethylene glycol monolaurate micelles, is shown to be possible. As a result of this substitution reaction both matrices control the growth of the “daughter” chains.

亜鉛ダイカストに使用するバレル研摩用コンパウンド

The experiment was performed in order to investigate the mechanism of generation of luster on zinc diecast by using various compounds including anionic, nonionic, or cationic surfactant.As a result, it was found that the degree of luster varies depending on the kind of surfactants used. The compound such as sodium stearate, toilet soap, polyethylene glycol monolaurate, polyethylene glycol lauryl ether, sodium salt of sulfonated lauryl alcohol, polyethylene glycol alkyl aryl ether, polyoxyethylene oleyl ether, or polyoxyethylene sorbitan monolaurate gave favorable result. However, the luster of the test pieces was poor when sodium lauric, soyabean-oil soap, or cation surfactants was used.