Preparation and hypoglycemic effect of insulin-containing chitosan-thioglycollic acid conjugates microspheres / 中国海洋药物

Objective To prepare insulin-containing chitosan-thioglycollic acid conjugates microspheres and evaluate their hypoglycemic effect.Methods The insulin-containing chitosan-thioglycollic acid conjugates microspheres were prepared by the dry-in-oil method using the chitosan-thioglycollic acid conjugates which the content of thiol group was 983?mol?g-1.The hypoglycemic effect of the microsphere was evaluated by drug release test in vitro and hypoglycemic test on hyperglycemic rats.Results The insulin-containing chitosan-thioglycollic acid conjugates microspheres with an average diameter of 13?m were administered by intraduodenal and intraileal application,and gave visible decrease in plasma glucose level in 4h at a dose of 20IU?kg-1.The relative bioavailability of the latter compared to hypodermic injection was 29.9%.Couclusion The results showed that the bioavailability of oral insulin could be facilitated by insulin-containing chitosan-thioglycollic acid conjugates microspheres,and good biological availability was obtained when the microspheres were administered by intraileal application.

Preparation and characterization of the chitosan-thioglycolic acid conjugates / 中国海洋药物

Objective To prepare a new bioadhesive material-chitosan-thioglycolic acid conjugates from chitosan,and analysed the structure moreover.Methods Preparing chitosan-thioglycolic acid conjugates with a new synthesis method under catalytic reaction by NHS,and the contents of thiol groups in the conjugates were determined.Furthermore,elemental analysis and the IR spectrum of the polymer were determined.Results The content of thiol groups in the chitosan-thioglycolic acid conjugates was 1034?mol?g~(-1),and the structure was elucidated.Conclusion The new synthesis method was feasible,and the structure can be elucidated by IR spectrum.

Research on the relation between the content of thiol group and in vitro adhesion of the chitosan-thioglycolic acid conjugates / 中国海洋药物

Objective Research on the relation between the content of thiol group in chitosan-thioglycolic acid conjugates and in vitro adhesion. Methods Prepared chitosan-thioglycolic acid conjugates with different content of thiol group,and determined the swelling behavior,instant detachment force between test disc and mucosa,recorded the maximum detachment force(MDF),and calculated the total work of adhesion(TWA)of these samples.Results The relation between the content of thiol groups and in vitro adhesion of the chitosan-thioglycolic acid conjugates was positive correlation, the adhesion of the polymer increased along with the content of thiol group,but the rate decreased.Conclusion The adhesion of chitosan-thioglycolic acid conjugates with higher content of thiol gyoup was far more stronger than chitosan.

Hypoglycemic Effect of the Alcohol Extract from the roots of Salacia Hainanensis / 中药新药与临床药理

Objective to evaluate the hypoglycemic effect of the alcohol extract from the roots of Salacia hainanensis.Methods observe the hypoglycemic effect of the alcohol extract from the roots of Salacia hainanensis on Alloxan model mice, and the influence on the blood glucose level of the glucose- loaded mice and normal mice. Results the alcohol extract from the roots of Salacia hainanensis could significantly reduce the blood glucose levels of the Alloxan mice and the glucose- loaded mice, while had no hypoglycemic effect on the normal mice. Conclusion the alcohol extract from the roots of Salacia hainanensis had remarkable hypoglycemic effect but the normal mice.