Preparation And Application Study Of Chitosan's Derivatives

Chitosan is natural amino polysaccharid that is reproducible nontoxic compatible and degenatable. Chitosan is only dessolved in the diluted acid solution which restrains its abroad application. In this research, chitosan and carboxyl methyl chitosan prepared by ourselves complexed with Fe ion of metal elements, the optional complexed conditions were investigated. The optional synthesised conditions of N-phthaloyl chitosan were studied. The N-phthaloyl chitosan was used as the coating material coated on the model drug of Propranolol, its sustained release performance as film coating material was studied. It is the purpose to provide baisic data for broadening the scope of application of chitosan through this research.(1)The appropriate weight of chitosan and carboxymethyl chitosan was respectively dissolved in the beaker, then Fe ion solution added, stirred for a certain period of time. The absorption of filtrate solution was measured at the appropriate UV wavelength. According to the standard curve, the concentration of Fe ion was calculated after the reaction. The complexed performance results of chitosan and carboxymethyl chitosan were as follows: the maxminum adsorption quantity of Fe(Ⅱ) on chitosan was 1.8mmol/g at pH 2.8; the maxminum adsorption quantity of Fe(Ⅱ) on carboxymethyl chitosan was 4mmol/g at pH 4; the maxminum adsorption quantity of Fe(Ⅲ) on chitosan was 4mmol/g at pH 3.5; the maxminum adsorption quantity of Fe(Ⅲ) on carboxymethyl chitosan was 6mmol/g at pH 4. The complexed performance of ion on carboxymethyl chitosan was better than chitosan, the adsorption performance of Fe(Ⅲ) was better than Fe(Ⅱ).(2)The acylation reaction of chitosan and phthalic anhydride was advanced. The influencing factors on the reaction of the orthogonal experiment were studied. After ascertaining the experiment conditions, the influencing experiment of single factor was investigated. The N-phthaloyl chitosan was characterized with the IR and UV. The optional reaction conditions of acylation of chitosan and phthalic anhydride were certainly confirmed: temperature 105℃, reaction time 2h, proportion of material quality 1:1.8(chitosan: phthalic anhydride). The IR result of product showed that there were obvious absorption peaks at 1714cm-1, 1635cm-1; the UV result demonstated that there was a maxmium absorption at 292nm, but chitosan have no absorption at 200—400nm.(3) The aqueous dispersion solution of N-phthaloyl chitosan was coated on the tablets of Propranolol which was used as the model drug. The optional prescription of N-phthaloyl chitosan aqueous dispersion and the optional coating technology of tablets were studied through the goals of coating effect of tablets, the cumulative released degree and the integrity of coating tablets after releasing. The stablity of sustained release tablets was conducted. The comparison result demonstrated that the coating effects of N-phthaloyl chitosan aqueous dispersion was better than its water suspension. The optional prescriotion of aqueous dispersion was as follows:N-phthaloyl chitosan(1.5g); dibutyl phthalate(2mL); magnesium stearate(0.3g); distilled water (150mL). The optional coating technology conditions were as follows:coating solution volume (250%); coating temperature(70℃) ; rotation rate of coating pan (55r/pm); rotation rate of cross-flow pump(50r/pm); spay pressure(90MPa).The iron adsorption quantity of Chitosan and carboxymethyl chitosan derivatives was abundant and the stability of their complexes was modest. So, it can be abroadly petentionally applicated at the iron adsorption field. The sustained release tablets of Propranolol prepared was released stably, N-phthaloyl chitosan used as the coating material of sustained release tablets was promising.