A novel approach has been developed for the preparation of strongly green-photoluminescent graphene quantum dots (GQDs-PEG) which have been surface-passivated by polyethylene glycol. The photoluminescence (PL) quantum yield of the GQDs-PEG with 400 nm excitation was about 18.8%, which was higher than other GQDs reported in the literature. More importantly, the surface-passivated PEG on GQDs can...

Potassium tribromide wrapped around polyethylene glycol ({K+PEG400}Br3-) was easily prepared by two step reaction of PEG400 with KBr followed by the addition of molecular bromine to give PEG embedded potassium tribromide as a dark viscous oil. The synthesized material was found to be an efficient, cost effective, environmentally benig...

     In this study, the stability of trinitroglycerin (TNG) in polyethylene (PEG) 400 was investigated according to Arrhenius approach. The reaction rate constant (k) for the thermal disintegration of TNG in PEG 400 at various temperatures was counted based on the percents of remaining TNG at different intervals of time at a specific temperature. The results showed that “k” at 40, 50, 60, 70, 8...

Celecoxib, a diaryl substituted pyrazole, is practically insoluble in water which precludes its use in parenteral and liquid dosage forms. This study explores the solubility enhancement of celecoxib using hydrotropy and cosolvency solubilization approaches. The equilibrium solubility studies were performed using hydrotropes piperazine, sodium citrate, and urea and cosolvents PEG 200, PEG 400, P...

In the present investigation, mixed-solvency approach has been applied for the enhancement of aqueous solubility of a poorly water- soluble drug, zaltoprofen (selected as a model drug), by making blends (keeping total concentrations 40% w/v, constant) of selected water-soluble substances from among the hydrotropes (urea, sodium benzoate, sodium citrate, nicotinamide); water-soluble solids (PEG-...

A series of trans- or cis-stilbenes have been synthesized in good to excellent yields via a functional group-dependent decarboxylation process from the corresponding 2,3-diaryl acrylic acids in a neutral CuI/1,10-phen/PEG-400 system under microwave conditions. The in situ generation of the recyclable catalytic complex, the use of environmentally benign solvent PEG-400, the operational simplicit...

Transdermal drug delivery systems of salbutamol sulphate using eudragit RL100 and PVP were developed by solvent casting technique employing mercury as a substrate. Propylene glycol was used as a plasticizer. The prepared films exhibited satisfactory physico-chemical characteristics. In vitro permeation profiles across the guinea-pig dorsal skin using K-C diffusion cell are reported. Incorporati...

In order to evaluate the gelation behavior of macromonomeric azoinitiators (MIMs), the free radical polymerization of MIM and macrocrosslinkers (MCRs) have been compared. MIMs were synthesized by the reaction between 4,49-dicyano-4,49-azovaleryl chloride and poly(ethylene glycol)s PEG-400, -1000, -1500, -2000 and 4-vinylbenzyl chloride. MCRs were obtained by vinylation of both hydroxyl ends of ...

Polycondensations were performed at 70 degrees C in bulk using physically immobilized lipase B from Candida antarctica (CAL-B) as catalyst. Study of copolymerizations between sebacic acid and PEG diols of differing Mn values (200, 400, 600, 1000, 2000, and 10 000) showed that PEG 400 and 600 were most reactive (DP(avg) up to about 6). Increasing the PEG diol chain length from 600 to 1000, 2000,...