Synthesize Of Glucosyl Substituent Polyphosphazene Hydrogels

Glucosyl substituent polyphosphazene has excellent biocompatibilityability and biodegradability. Its degradation products are non-toxic. And thehydrophilicity/hydrophobicity balance of the polymer can be adjusted bychanging the ratio of hydrophilic groups and hydrophobic groups. Hydrogelcan be prepared by mixing glucosy substituent polyphosphazene and lectin(Con A), which can be used for glucose-sensitive insulin delivery. Becauseof these excellent properties, glucosy substituent polyphosphazenes has abright future in the study of insulin release system.In this thesis, we synthesized glucosy substituent polyphosphazene byprotecting and deprotecting the hydroxy groups of glucose before and atterreacting with poly(dichlorophosphazene). The polymers were mixed with ConA in aqueous solution and transmittance of the solution was measured toinspect the interaction between glucosyl substituent polyphosphazene and ConA. Details were described as follows:1) 1,2:5,6-di-O-isopropylidene-a-D-glucofuranose was synthesized fromα-D- glucose and acetone using zinc chloride and phosphoric acid as catalysts.And the product was characterized by melting point measurement and ~1HNMR analysis. Influences of acetone, zinc chloride, phosphoric acid and reaction time on the yield of 1,2:5,6-di-O-isopropylidene-α-D-glucofuranosewere studied.2) The poly(dichlorophosphazene) was substituted by sodium salt of diacetoneD-glucose first and the residual P—C1 were substituted by over amount ofnucleophilic compounds (methoxy ethanol or ethylglycine was used in thisthesis). Removement of isopropylidene group to restore the hydroxyl groupswas performed by adding trifluoroacetic acid. The influence of deprotectiontime on the structure of the polymer was discussed.Interaction of Con A with glucosyl-co-(2-methoxy) ethoxy substituentpolyphosphazene or glucosyl-co-ethylglycine substituent polyphosphazenein aqueous solution was determined by measuring their transmittance at360nm at room temperature.4) Properties of the obtained polyphosphazene hydrogel were studiedprimarily.