Mixture Of Polyethylene Glycol Research Articles

Piroxicam Solubility in Binary and Ternary Solvents of Polyethylene Glycols 200 or 400 with Ethanol and Water at 298.2 K: Experimental Data Report and Modeling

The solubilities of piroxicam in binary and ternary mixtures of polyethylene glycols 200 or 400 with ethanol and water (138 data points) at 298.2 K were determined and mathematically represented by cosolvency models. The solubilities were measured using the shake flask method and the models are used to fit the solubility data of piroxicam in the solvent mixtures. The overall mean relative deviations (OMRDs %) for fitting the solubility data of piroxicam in binary and ternary mixtures using the Williams–Amidon and Jouyban–Acree models are 30.7 and 26.8 %, respectively, and the OMRD % values for predicting the solubilities of piroxicam by the trained versions of the Jouyban–Acree model is 57.3 %.

CuAlO2 powder dispersed in composite gel electrolyte for application in quasi-solid state dye-sensitized solar cells

The use of delafossite CuAlO2 (CAO) powder as an additive in composite gel electrolyte (CGE) of the quasi-solid state dye-sensitized solar cell (DSSC) is first reported. In order to achieve an improvement of power conversion and long-term performance of the quasi-solid state DSSC, different contents of CAO powder containing in CGE, a mixture of polyethylene glycol (PEG), iodide/tri-iodide (I−/I3−) liquid electrolyte (LE) and 4-tertbutylpyridine (4-tBP), were used in the present study. The photocurrent density–voltage characteristic (J–V curve) and photovoltaic performance parameters of the cells, such as the short-circuit current density (Jsc), open-circuit voltage (Voc), power conversion efficiency (η) and fill factor (FF) were investigated. The CGE containing the dispersed CAO powder exhibited high ionic conductivity due to the charge diffusion through free channels. The power conversion efficiency of the quasi-solid state DSSC was significantly improved by adding CAO powder to the CGE. The optimum CAO powder content in the CGE was 0.05wt%. In this research, the power conversion efficiency was 1.71 times of the LE and 2.85 times of the CGE with no CAO powder adding. The quasi-solid state DSSC based on the addition of CAO powder to CGE had long-term stability better than the normal DSSC based on the LE.

Naproxen solubility in binary and ternary solvents of polyethylene glycols 200, 400 or 600 with ethanol and water at 298.2 K – experimental data report and modelling

The solubilities of naproxen in the binary and ternary mixtures of polyethylene glycols 200, 400 or 600 with ethanol and water (185 data points) at 298.2 K are determined and mathematically represented by cosolvency models. The obtained overall mean relative deviations (OMRDs) for fitting the solubility data of naproxen in binary and ternary mixtures using Williams–Amidon and Jouyban–Acree model are 15.7% and 16.5%, respectively, and the OMRD values for predicting the solubility data of naproxen by the trained versions of Williams–Amison and Jouyban–Acree models are 71.1% and 64.4%, respectively.

Some Physical Properties of <i>Vernonia amygdalina</i> and <i>Garcinia kola</i> Microspheres Prepared with High Molecular Weight Polyethylene Glycols

The effect of polymer concentrations on some of the physicochemical properties of Vernonia amygdalina (Linn) and Garcinia kola (Heckel) extracts loaded microspheres was evaluated. Microspheres of the aqueous extracts was prepared by emulsion solvent evaporation using polyethylene glycol (PEG) mixtures of molecular weight 4000 and 6000 at different ratios of 1:0, 0:1, 1:1, 1:2 and 2:1 while the amounts of the extracts incorporated was constant for all ratios. The microspheres were evaluated for their particles sizes, yield, flavonoid content, loading efficiency, moisture loss and flow properties. In-vitro release studies were carried out by monitoring flavonoid release rate from the microspheres. The microspheres were spherical and uniformly shaped and exhibited good flow characteristics. Their size range, yield, loading efficiency, moisture loss and flavonoid content were 76 - 83 im, 49 - 76 %, 47 - 82 %, 2.18 - 4.60 % and 17.10 - 23.80 mg%, respectively for V. amygdalina and 144 - 160 im, 50 - 68 %, 51 - 68 %, 3.00 - 4.41 % and 20.00 - 28.70 mg%, respectively for G. kola . Flavonoids release from the microsphere was up to 90 % within 1 h and it followed a matrix release kinetic model with a super case-II transport mechanism. The concentrations of the polymers affected the yield, loading efficiency, moisture loss and the extent of flavonoid release of the microspheres but had no effect on their particle sizes and flavonoid content. These results may find useful application in the delivery of V. amygdalina and G. kola extracts since the combination of PEG of different molecular weights resulted in microspheres with good physicochemical and release properties. © JASEM

Self‐diffusion and interactions in mixtures of imidazolium bis(mandelato)borate ionic liquids with polyethylene glycol: 1H NMR study

We used (1) H nuclear magnetic resonance pulsed-field gradient to study the self-diffusion of polyethylene glycol (PEG) and ions in a mixture of PEG and imidazolium bis(mandelato)borate ionic liquids (ILs) at IL concentrations from 0 to 10 wt% and temperatures from 295 to 370 K. PEG behaves as a solvent for these ILs, allowing observation of separate lines in (1) H NMR spectra assigned to the cation and anion as well as to PEG. The diffusion coefficients of PEG, as well as the imidazolium cation and bis(mandelato)borate (BMB) anion, differ under all experimental conditions tested. This demonstrates that the IL in the mixture is present in at least a partially dissociated state, while the lifetimes of the associated states of the ions and ions with PEG are less than ~30 ms. Generally, increasing the concentration of the IL leads to a decrease in the diffusion coefficients of PEG and both ions. The diffusion coefficient of the anion is less than that of the cation; the molecular mass dependence of diffusion of ions can be described by the Stokes-Einstein model. NMR chemical shift alteration analysis showed that the presence of PEG changes mainly the chemical shifts of protons belonging to imidazole ring of the cation, while chemical shifts of protons of anions and PEG remain unchanged. This demonstrated that the imidazolium cation interacts mainly with PEG, which most probably occurs through the oxygen of PEG and the imidazole ring. The BMB anion does not strongly interact with PEG, but it may be indirectly affected by PEG through interaction with the cation, which directly interacts with PEG.

Enhanced antifouling behaviours of polyvinylidene fluoride membrane modified through blending with nano-TiO2/polyethylene glycol mixture

Titanium dioxide (TiO2) nanoparticles/polyethylene glycol (PEG) mixture was used to modify polyvinylidene fluoride (PVDF) membranes aiming to improve their antifouling ability. The use of PEG could improve the dispersion of nanoparticles thanks to steric hindrance effects. Test results showed that compared to the original PVDF membrane, the modified membranes had higher hydrophilicity and lower negative Zeta potential, facilitating membrane fouling control. The extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) analysis indicated that the addition of TiO2 nanoparticles improved their electron donor monopolarity, i.e., enhanced electron-donating ability. The interaction energy barrier between soluble microbial products (SMP) and membrane surfaces was also improved, indicating that anti-fouling ability of the modified membrane was elevated. The optimal dosage of nano-TiO2 was found to be 0.15%, and further increase of dosage resulted in the aggregation of nanoparticles which consequently impaired the modification efficiency. Quartz crystal microbalance with dissipation (QCM-D) monitoring and SMP filtration tests confirmed the antifouling ability of the modified membrane.

Multi-Stimulus-Responsive Shape-Memory Polymer Nanocomposite Network Cross-Linked by Cellulose Nanocrystals

In this study, we developed a thermoresponsive and water-responsive shape-memory polymer nanocomposite network by chemically cross-linking cellulose nanocrystals (CNCs) with polycaprolactone (PCL) and polyethylene glycol (PEG). The nanocomposite network was fully characterized, including the microstructure, cross-link density, water contact angle, water uptake, crystallinity, thermal properties, and static and dynamic mechanical properties. We found that the PEG[60]-PCL[40]-CNC[10] nanocomposite exhibited excellent thermo-induced and water-induced shape-memory effects in water at 37 °C (close to body temperature), and the introduction of CNC clearly improved the mechanical properties of the mixture of both PEG and PCL polymers with low molecular weights. In addition, Alamar blue assays based on osteoblasts indicated that the nanocomposites possessed good cytocompatibility. Therefore, this thermoresponsive and water-responsive shape-memory nanocomposite could be potentially developed into a new smart biomaterial.

Development of a novel pelletization technique through an extremely high-shear process using a mechanical powder processor to produce high-dose small core granules suitable for film coating

We established an extremely high-shear melt pelletization technique using a mechanical powder processor to produce high-dose granules smaller than 300μm with properties suitable for film coating. A mixture of ethenzamide and polyethylene glycol (used as a low-melting binder) at various weight ratios was mechanically treated under various jacket temperatures. When the jacket temperature was set to 50°C or greater, the product temperature reached the melting point of the binder, resulting in pelletization. The drug powder were pelletized with a small amount of binder to yield pellets of approximately 150μm with a drug content of more than 90%. The mechanism of melt pelletization through ultrahigh shearing involves a series of nucleation, consolidation, coalescence and breakage stages. The power consumption profile corresponding to each stage in the pelletization revealed that pellets between 75 and 300μm were effectively obtained at a large power consumption peak. The resultant pellets showed comparative sphericity and smoothness, and higher durability than commercial core granules for film coating. In conclusion, this study demonstrates that the extremely high-shear melt pelletization technique can give drug pellets with desirable properties as core particles for the coating process.

Preliminary Studies of the Effects of Polyethylene Glycol/Hydroxyapatite Powder-Binder System for 3D Printing Application

The role of binder in powder system has gained its importance lately in 3D printing (3DP) applications. This research aims to investigate the effect of powder system developed from incorporation of polyethylene glycol (PEG) onto hydroxyapatite (HAP) powder for 3D printing application. Simple spray method was used to incorporate mixture of PEG into HAP powder. Raw commercial HAP powder was determined by using particle size analyser. The morphology and crystallinity of raw HAP powder and powder mixture were characterised by using Scanning Electron Microscopy (SEM) and X-ray Diffractive (XRD) analysis. Mean particle size of raw HAP was found to be 4.77 μm which is suitable for 3D printing and in good agreement with SEM micrographs. Based on the SEM micrographs, the powder mixture was found in agglomerated and small particle form. Small amount of PEG (2 wt. % to 7 wt. %) incorporation onto HAP powder exhibited absence of new phases on XRD analysis, demonstrating good chemical compatibility. Based on this study, it can be concluded that incorporating PEG onto HAP powder is able to maintain the initial characteristic of HAP and can work together as powder system.

PEGylation and incorporation of triazine ring into thin film composite reverse osmosis membranes for enhancement of anti-organic and anti-biofouling properties

An approach for the simultaneous enhancement of anti-organic and anti-biofouling properties of polyamide thin film composite (TFC) reverse osmosis (RO) membranes is reported. In situ incorporation of both triazine ring and polyethylene glycol (PEG) into the polyamide network yielded such TFC membranes. The polyamide active layer was fabricated on top of polysulfone support membrane via interfacial polymerization (IFP) between conventionally used trimesoyl chloride (TMC) and mixture of m-phenylenediamine (MPD), melamine and MPD-terminated PEG (MeO-PEG-MPD). The membrane prepared by MPD/melamine/MeO-PEG-MPD exhibited superior overall antifouling properties compared to membrane prepared by MPD/melamine or MPD as sole amine monomer. It turned out that the incorporated PEG enhances anti-organic fouling property and reduces the bacterial adhesion whereas triazine ring only lowers the growth of bacteria on TFC membrane surface. The membrane containing both triazine ring and PEG exhibited pronounced effect on reducing bacterial adhesion than that of membrane containing triazine alone. TFC membrane prepared by IFP between TMC (0.125%, w/v) and mixture of MPD+melamine+MeO-PEG-MPD (MPD:melamine:MeO-PEG-MPD=1:1:0.5 w/w) exhibited enhanced overall antifouling property with permeate flux ca. 38Lm−2h−1 and NaCl rejection ca. 93% from feed solution (containing 2000ppm NaCl) at applied pressure 1.4MPa.

Pcl/Peg Electrospun Fibers as Drug Carriers for the Controlled Delivery of Dipyridamole

Electrospinning is a versatile and diverse technology for the production of nano- and microfibers that can be used as a drug delivery system (DDS). The aim of this study was to create fibrous scaffolds from a mixture of polycaprolactone (PCL) and polyethylene glycol (PEG) and to evaluate the suitability of the fibers as DDS. Dipyridamole (DPA), an anti-thrombotic and anti-proliferative pharmaceutical agent, was used as a model drug. Two types of PEG with different chain length were used. The structural, mechanical and physicochemical characteristics of the fibers with and without DPA, were determined, and the release kinetics of DPA were studied. The obtained fibers loaded with DPA and with the higher molecular weight PEG were smooth and had an average diameter of 586.75 ± 204.79 nm and an average Young’s modulus of 57.14 ± 4.35 MPa, whereas the tensile strain at break was 0.61 ±0.05 mm/mm and the ultimate tensile strength (UTS) was 16.79 ± 3.08 MPa. The cumulative release of DPA revealed two stages: an initial burst phenomenon followed by slower Fickian diffusion (release exponent n = 0.432).

Synthesis of Chitosan-Coated Magnetic Microparticle Using Glutaraldehyde as Crosslinker and PEG as Spacer Arm and Its Application as Adsorbent of Peat Humic Acid

A simple procedure for synthesis of chitosan-coated magnetic microparticle (CMMP) using glutaraldehyde as a cross-linker and polyethylene glycol (PEG) as a spacer arm has been developed. The functionalized microparticle were prepared using an inexpensive, simple, rapid, one-pot process, based on the heating of chitosan, PEG, and ferrous sulfate mixture at high pH. X-ray diffraction results indicated that the surfacemodified Fe3O4 microparticle did not lead to phase change unlike the pure Fe3O4. Magnetic chitosan adsorbent has been evaluated for removal of peat humic acid from its aqueous solution.

Facile synthesis of methotrexate intercalated layered double hydroxides: Particle control, structure and bioassay explore

To study the influence of particle size on drug efficacy and other properties, a series of methotrexate intercalated layered double hydroxides (MTX/LDHs) were synthesized through the traditional coprecipitation method, using a mixture of water and polyethylene glycol (PEG-400) as the solvent. To adjust the particle size of MTX/LDHs, the dropping way, the volume ratio of water to PEG-400 and different hydrothermal treatment time changed accordingly, and the results indicate that the particle size can be controlled between 90 and 140nm. Elemental C/H/N and inductive coupled plasma (ICP) analysis indicated that different synthesis conditions almost have no effect on the compositions of the nanohybrids. X-ray diffraction (XRD) patterns manifested the successful intercalation of MTX anions into the LDH interlayers, and it's also found out that different volume ratios of water to PEG-400 and variable dropping way can affect the crystallinity of the final samples, i.e., the volume ratio of 3:1 and pH decreasing are proved to be optimum conditions. Furthermore, both antiparallel monolayer and bilayers adopting different orientations are suggested for four samples from XRD results. Fourier transform infrared spectroscopy (FTIR) investigations proved the coexistence of CO32− and MTX anions in the interlayer of the nanohybrids. MTX/LDH particles exhibited hexagonal platelet morphology with round corner and different dropping ways can affect the morphology greatly. Moreover, a DSC study indicated that longer time treatment can weaken the bond between the MTX anions and LDH layers. The kinetic release profiles told us that larger MTX/LDH particles have enhanced the ability of LDH layers to protect interlayer molecules. At last, the bioassay study indicated that the nanohybrids with larger diameters have higher tumor suppression efficiency.

Optimization of one-step and one-substrate synthesis of carbon nanodots by microwave pyrolysis

The effect of water on the optical properties and concentration of carbon nanodots (CND), prepared by microwave heating of a mixture of polyethylene glycol 200 (PEG-200) and water, was studied. It was shown that the presence of water as a substrate leads to the synthesis of CND with lower yield and optical properties and it is better to use only PEG-200 as the substrate. Microwave power and irradiation time as two important variables in the synthesis of CND from a single substrate (PEG-200) were optimized to obtain CND with a high yield. The CND obtained under the best conditions were characterized by TEM, XRD, UV-Visible, fluorescence spectroscopy and fluorescence imaging. Consequently, photostability of the prepared CND in acidic and alkaline mediums was studied. Finally, it was shown that the produced CND can be used as a green and cheap reagent for fast detection of metronidazole based on fluorescence quenching.

Investigation of the weak basic butyltriethylammonium acetylacetonate and polyethylene glycol mixture as a new efficient CO2 absorption solvent

Efficient and reversible absorption of CO2 was investigated by weak basic ionic liquid of butyltriethylammonium acetylacetonate ([N2224][acac]) and polyethylene glycol 200 (PEG-200) mixtures with different mass ratios. The results showed that [N2224][acac]/PEG-200 mixtures possessed a maximum absorption capacity of 0.9mol CO2 per mole [N2224][acac] at T=298.15K under ambient pressure. The mixtures used could be easily regenerated by bubbling N2 through the solutions without obvious loss of absorption performance. Furthermore, the solubility data of CO2 in the mixtures at T=(303.15, 318.15, and 333.15)K under different pressures were measured. The thermodynamic parameters of absorption enthalpy and absorption entropy were calculated with resulting negative values at each condition. The mixtures showed low absorption enthalpy for CO2 capture. The addition of PEG-200 can accelerate absorption process. The CO2 capture process described using [N2224][acac]/PEG-200 mixtures is a promising method for CO2 absorption with both good reversibility and high absorption capacity.

Comparison of Solvent-Casting and Melt-Compounding Blended Biomedical (Polylactide)-(Polyethylene Glycol) Mixture as Drug Carrier

For the purpose of drug carrier and delivery, the polylactide was modified by polyethylene glycol blending with the weight percentage of 80/20 by two methods: solvent-casting and melt-compounding. Characterizations of X-ray diffraction, Scanning Electron Microscope and degradation experiments have been done to study the crystallization, miscibility and degradation behavior. The melt-compounding provides a better miscibility associated with longer degradation time, however the heating procedure effects the polymers. Because of the heating and cooling cycle, the polymers had an opportunity to crystalize and the crystal peak can be seen in the XRD results. While the solvent-casting avoids the high temperature experience of blend with an amorphous state, and provides lower miscibility and short degradation time. These significant features will be considerable factors in drug carrier design.

ChemInform Abstract: Effect of Aqueous Polyethylene Glycol on 1,3‐Dipolar Cycloaddition of Benzoylnitromethane/Ethyl 2‐Nitroacetate with Dipolarophiles: Green Synthesis of Isoxazoles and Isoxazolines.

AbstractIt is demonstrated that a 1:1 mixture of water and polyethylene glycol 400 promotes the 1,3‐dipolar cycloaddition of carbonyl substituted nitromethanes (I) to terminal alkynes or analogously activated olefins without the need for any catalyst or additive.

Influence of the liquid viscosity on the formation of bubble structures in a 20 kHz field

The cavitation field in a cylindrical vessel bottom-insonified by a 19.7kHz large area transducer is studied experimentally. By adding controlled amounts of Poly-Ethylene Glycol (PEG) to water, the viscosity of the liquid is varied between one- and nine-fold the viscosity of pure water. For each liquid, and for various displacement amplitudes of the transducer, the liquid is imaged by a high-speed camera and the acoustic field is measured along the symmetry axis. For low driving amplitudes, only a spherical cap bubble structure appears on the transducer, growing with amplitude, and the axial acoustic pressure field displays a standing-wave shape. Above some threshold amplitude of the transducer, a flare-like structure starts to build up, involving bubbles strongly expelled from the transducer surface, and the axial pressure profile becomes almost monotonic. Increasing more the driving amplitude, the structure extends in height, and the pressure profile remains monotonic but decreases its global amplitude. This behavior is similar for all the water–PEG mixtures used, but the threshold for structure formation increases with the viscosity of the liquid. The images of the bubble structures are interpreted and correlated to the measured acoustic pressure profiles. The appearance of traveling waves near the transducer, produced by the strong energy dissipated by inertial bubbles, is conjectured to be a key mechanism accompanying the sudden appearance of the flare-like structure.

Evaluation of Polycaprolactone Matrices for Sustained Vaginal Delivery of Nevirapine in the Prevention of Heterosexual HIV Transmission

Nevirapine (NVP) was loaded in polycaprolactone (PCL) matrices to produce vaginal inserts with the aim of preventing HIV transmission. NVP dispersions in PCL were prepared, at 10% (w/w) theoretical loading, measured with respect to the PCL content of the matrices, in the form of (1) NVP only, (2) a physical mixture of NVP with polyethylene glycol (PEG) 6000 or (c) a solid dispersion (SD) with PEG produced by co-dissolution in ethanol. Characterisation of SD by differential scanning calorimetry and attenuated total reflectance-Fourier transform infrared spectroscopy suggested transformation of the crystalline structure of NVP to an amorphous form which consequently increased the dissolution rate of drug. A low-loading efficiency of 13% was obtained for NVP-loaded matrices and less than 20% for matrices prepared using physical mixtures of drug and PEG. The loading efficiency was improved significantly to around 40% when a 1:4 NVP-PEG SD was used for matrix production. After 30 days, 40% of the drug content was released from NVP-loaded matrices, 55% from matrices containing 1:4 NVP-PEG physical mixtures and 60% from matrices loaded with 1:4 NVP-PEG SDs. The in vitro anti-viral activity of released NVP was assessed using a luciferase reporter gene assay following the infection of HeLa cells with pseudo-typed HIV-1. NVP released from PCL matrices in simulated vaginal fluid retained over 75% anti-HIV activity compared with the non-formulated NVP control. In conclusion, 1:4 NVP-PEG SDs when loaded in PCL matrices increase drug loading efficiency and improve release behaviour.

Pore size-controlled synthesis of PEG-derived porous TiO2 particles and photovoltaic performance of dye-sensitized solar cells

Porous TiO2 particles having a controlled pore size were synthesized from colloidal mixtures of TiO2 nanoparticles and polyethylene glycol (PEG) via an aerosol templating method. The effect of a PEG addition on the pore properties of the as-prepared porous TiO2 particles was systematically investigated. A larger amount of PEG led to porous TiO2 particles with higher specific surface areas and total pore volumes originating from the removal of the PEG during a heat treatment. Furthermore, the photovoltaic characteristics of dye-sensitized solar cells (DSSCs) fabricated with porous TiO2 photoanodes having different pore properties were estimated. The photovoltaic conversion efficiency of the DSSCs was found to be strongly dependent on the pore properties of the TiO2 photoanode. The DSSC fabricated with the TiO2 photoanode prepared with 0.25wt% of PEG showed the highest conversion efficiency of 6.17%, which was approximately 170% higher than that of DSSC fabricated with a TiO2 photoanode without PEG.