BIODEGRADABLE MULTI-BLOCK COPOLYMERS OF POLY(L-LYSINE) AND POLY (ETHYLENE GLYCOL) FOR THE DELIVERY OF BIOACTIVE AGENTS

摘要

Biodegradable and non-toxic multi-block copolymers based on poly(L-lysine) and poly(ethylene glycol) were synthesized. Synthesized copolymers showed almost negligible cytotoxicity and biodegradability under physiological condition within the time scale of in vitro experiments. For an efficient gene transfection, an endosomal escape moiety based on histidine derivatives was conjugated. Conjugated copolymers displayed 6 times higher transfection efficiency than that of PLL homopolymer with negligible cytotoxicity. Transfection efficiencies of copolymers with and without conjugation were not affected by the presence of serum, while that of PLL homopolymer decreased to the level of naked gene in the presence of serum.