Synthesis and Characterization of Lactobionic Acid Grafted Phenylalanyl-Glycyl-Chitosan

In order to enhance the target action of chitosan-based drug, this paper firstly prepared phenylalanyl-glycylchitosan (Phe-Gly-CS) by grafting the key intermediate, bromoacetyl-phenylalanine (BA-Phe) onto chitosan. Then the target sugar molecule, lactobionic acid (LA), was grafted to Phe-Gly-CS and the topic compound lactobionic acid grafted phenylalanyl- glycyl-chitosan (Phe-Gly-CS-LA) was finally obtained in a yield of 78.8%. The product were characterized by FTIR, MS and H-1 NMR. The preparing condition of BA-Phe was optimized as follows: the best pH was 10-11, the optimum temperature was -4 degrees C, the reaction time was 1.5 h.