In situ gelling systems based on temperature-dependent phase transition containing pheniramine and phenylephrine were developed using combination of Poloxamers, different cellulose polymers (HPMC) and xanthan gum. The formulations were tested for in vitro gelation, appearance, pH, drug content, in vitro drug release, mucoadhesive strength, preservative effi cacy and stability. In vitro release ...

In the past few years, an increasing number of in situ-forming systems have been reported in the literature for various biomedical applications, including drug delivery, cell encapsulation, and tissue repair. There are several possible mechanisms that lead to in situ gel formation: solvent exchange, UV-irradiation, ionic cross-linkage, pH change, and temperature modulation. The thermosensitive ...

The present work describes the formulation development of ophthalmic in situ gelling system using thermo-reversible gelling polymer, i.e. Pluronic F 127 (PF127). Because of high concentration (20 to 25%w/v) of this polymer required for in situ gelation causes irritation to the eye. So, to reduce this concentration, an attempt was made to combine the PF127 with other polymers like hydroxy propyl...

The clinical effectiveness of tissue conditioners is influenced by their gelation characteristics and viscoelastic properties after gelation. The purpose of this study was to evaluate the effect of addition of ethyl alcohol (EtOH) on these properties, and to compare the effect of EtOH with that of the powder/liquid (P/L) ratio. Three tissue conditioners were used in this study. The gelation tim...

In this paper, polyacrylamide/chromium acetate gel polymer system was prepared as water shut-off system to control water production in one of the Iranian oil reservoirs condition. Effect of various parameters such as temperature (90 °C) and water formation from view point of salinity and divalent cations, was evaluated on the gelation kinetic and gel strength using bottle testing method. Th...

sound power is considered as an excellent measure for evaluating the efficiency of noise controls as well as for comparing noise sources in workrooms. this parameter can be determined by sound pressure or intensity based methods in real conditions of workrooms. this paper aims empirically to compare these in situ methods in relation to a typical industrial machine located in workroom in terms o...

in this work, a thermoplastic polyurethane elastomer (tpue) model based on polytetramethylene glycol, toluene diisocyanate and 1,4-butanediol was selected and synthesized. according to this model two types of polyurethane nanocomposites were prepared by in situ polymerization and melt intercalation procedures. the organo-modified nanoclay was used in nanocomposites samples in 0.4 weight percent...

bis(2-r-ind)zrcl2 (r: h or phenyl) was supported on different types of silica by in situ impregnation method and used for ethylene polymerization. in this method, the step of catalyst loading on support was eliminated and common alkyl aluminum (triisobutylaluminum, tiba) cocatalyst was used instead of expensive methyl aluminiumoxane (mao) cocatalyst in the polymerization. the effect of surface ...