Patent ID: 6586524
Filing Date: 2003-07-01
Classification: A61K,C12N

Abstract:
A polymeric conjugate that functions as a gene carrier comprising a cationic polymer(CP) member grafted with a poly(ethylene glycol) member (PEG), which is in turn covalently bound to a targeting moiety(TM), wherein 0.1 to 10 mole percent of the cationic groups of said CP are substituted with said TM-PEG, said polymeric conjugate is synthesized by a process comprising: 1) obtaining a TM having one functional amine group or adding one functional amine group to the TM and a bifunctional PEG containing a &lgr;-vinyl sulfone(VS) at one terminal and a &ohgr;-N-hydroxysuccinimidyl ester(NHS) at the other terminal(VS-PEG-NHS); 2) reacting the amine group of the TM with the NHS group of the VS-PEG-NHS to obtain VS-PEG-TM; and 3) reacting the VS group of the VS-PEG-TM with the amine groups of the CP at a pH of 4 to 9 to obtain CP-PEG-TM.