Morphological and spectroscopical characterization of hyperbranched polyamidoamine-zwitterionic chitosan-encapsulated 5-FU anticancer drug

Hyperbranched polyamidoamines (PAMAM) have been widely investigated for therapeutic applications but their cytotoxicity caused by their cationic charges limited their spreading use in biomedical applications. Zwitterionic chitosan (ZWCs) is a biocompatible, pH sensitive and nontoxic polymer which can be used to reduce cytotoxicity by covering the PAMAM surface. The complex formed from synthesized PAMAM and ZWCs with different ratios was prepared at pH 7.4. Encapsulation of 5-Fluorouracil by these complexes has successfully been established for high efficiency drug delivery. The complex with ratio (3:1) ZWCs/PAMAM had average size similar to 310 nm and negatively charged at neutral pH confirming the ability of the ZWCs to cover PAMAM surface. The encapsulation efficiency ranged between 100 and 72.5% with loading capacity from 5 to 20% for different initial feed drug concentration 5-20 mg/ml. The release profile of ZWC-PAMAM complex showed sustained drug release up to period of 38 h.