After centrifugation the chitosan nanocomposites were freeze dried by freeze dry system at -70˚C and used for further analysis (Ali et al., 2010). Nanoparticles were coated on membrane The synthesized chitosan loaded nanoparticles (CN) and bioactive compound loaded chitosan nanocomposites (BCN) were coated on 0.4 micron membrane by dipping method. The membrane was placed in synthesized nanoparticles solution and kept in
ABSTRACT The purpose of this study was to investigate the efficiency of silicated chitosan in promoting tablet disintegration and drug dissolution in comparison with commonly used superdisintegrant crospovidone. Silicated chitosan was prepared by co-precipitation method and metoclopramide hydrochloride was used as a model drug for the preparation of fast dissolving tablets. Formulations containing silicated chitosan exhibited almost similar in-vitro dispersion time and in-vitro drug dissolution pattern in comparison with formulation containing crospovidone. The intimate physical association between chitosan and silica creates an insoluble, hydrophilic, highly absorbent material, consequently, resulting in superiority in water uptake, water saturation for gel formation and compatibility. IR spectroscopic studies of silicated chitosan, silica, chitosan and chitosan-silica physical mixture indicated that preparation method did not involve any chemical reaction and only physical modification occurred on chitosan particles.
DMF was used as a solvent and AIBN (0.5% w/w of total monomer) as free radical initiator .The reaction was carried out at 70±2° C for 6 hour with constant stirring. After completion of the process it was cooled to room temperature and resultant polymer solution was poured in the large amount of methanol with stirring when polymer precipitated out. It was filtered and washed with methanol. The polymer was purified by repeated precipitation using methanol from solution in DMF and then it dried. 2.3 Preparation of PS
In particular, the formulation of rosuvastatin, molecule which is generally lipophilic, poses real problems owing mainly to their low solubility in aqueous liquid pharmaceutical excipients, to their propensity to precipitate or recrystallize in aqueous solution and to their low solubility in the fluids of the gastrointestinal tract from which they must be absorbed. The bioavailability of an active ingredient also depends on its concentration in the gastrointestinal fluid, said concentration itself being dependent on the release of the active ingredient. In particular, the more lipophilic an active ingredient is, the less tendency it has to migrate in gastrointestinal fluids. The above said problem can be overcome by nanoparticle drug delivery
Its liver uptake is a biphasic process and its binding to the surface of hepatocytes is fast and reversible. One study demonstrated that the uptake of caspofungin by liver is related to the active organic anion transporting polypeptide 1B1 (OATP1B1) . Caspofungin plasma clearance is 10 to 12 ml/min  and eliminated mainly by hepatic, for only one to two percent of it is cleared renal . The elimination of caspofungin from plasma is
However, the narrow therapeutic window and multiorgan toxicity has limited it from further clinical use. In order to increase its therapeutic index, different kinds of triptolide-loaded delivery systems have been developed, which has been verified to change the pharmacokinetics of triptolide and decrease the toxicity. The pharmacokinetic study of a triptolide-loaded delivery system in mice showed that a targeted tissue accumulation and longer residence time were found in triptolide-loaded lipid emulsion . The AUC0-t of triptolide-loaded lipid emulsion increased 2.19 folds, suggesting that the triptolide-loaded lipid emulsion does improve the biodistribution, accumulation and therapeutic efficacy in pancreas. Moreover, the levels of triptolide-loaded lipid emulsion in heart, lung and kidney were lower than that of the triptolide group, which would reduce the toxicity of triptolide in the above tissues.
ZPFe (3 mol%) was added to a mixture of a benzoyl chloride (10 mmoL) and an aromatic compound (10 mmoL). The reaction mixture was stirred for the appropriate reaction times at 80 °C (Table 2). After completion of the reaction (monitored by thin-layer chromatography, TLC), the mixture was diluted with Et2O and filtered. The organic layer was washed with 10% NaHCO3 solution and then dried over anhydrous Na2SO4. The solvent was evaporated under reduced pressure and the product purified by column chromatography on silica gel to give the corresponding pure aryl
iv. 1,4 cyclohexanedimethanol (1,4 CHDM) 1,4 cyclohexanedimethanol is an alicyclic glycol , the cycloaliphatic structure of 1,4 cyclohexanedimethanol imparts particular conformational transitions and molecular structure to polyesters . Ni et al  stated that polyesters containing cyclic moieties in their backbone are of transitional mechanical properties in comparison to aromatic and linear polyesters. 1,4 cyclohexanedimethanol could provide an excellent compromise between hardness and flexibility. The two primary hydroxyl functionalities provide excellent reactivity during both the esterification process and the subsequent crosslinking reaction.
Due to the varying pressures that protein A chromatography columns are exposed to during processing the integrity of the material may sometimes be compromised. This increased pressure is readily seen with increased flow rates and hence put a greater stress on the system to attain optimised affinity is required. This can be readily seen with the beaded agarose support material (Cube Biotech) Fig. 25 above conveys increased agarose concentration and also increased cross linking. This increased concentration and cross linking is responsible for increased durability and make it somewhat robust.
Effect of γ-rays on carboxymethyl chitosan for use as antioxidant and preservative coating for peach fruit Ahmed M. Elbarbarya* and Tahia B. Mostafab a Polymer Chemistry department, National Center for Radiation Research and Technology, Nasr City, Cairo, Egypt b College of Women, Ain Shams University, Cairo, Egypt Abstract Carboxymethyl chitosan (CMCS) was synthesized by alkylation of chitosan using monochloroacetic acid and characterized by FTIR and 1H-NMR spectroscopy. Different molecular weights (Mw) of CMCS were prepared by radiation degradation of CMCS in the solution form at different irradiation doses. The structural changes and Mw of degraded CMCS were confirmed by UV-Vis, FTIR and GPC. The antioxidant activity of CMCS were evaluated