New Synthetic Polymers for Enzyme and Liposome modification

摘要

Although most enzyme and liposome modification have been carried out using linear forms of poly(ethylene glycol), new polymers of ntural or synthetic origin have also been employed and udner study. A branched structure that, in many respects was found to be superior to the linear one, is similar to poly(ethylene glycol) in structure and single point attachment. New single point attachment polymers were recently synthesised and among these are poly(vinylpyrrolidone) and poly(acryloylmorpholine) oligomers which were successfully used for both enzyme and liposome modification, and poly(oxazoline) and poly(glycerols) which were used for long lasting liposome protection. Among the multifunctional reagents of note are dextran, divinyl ethermaleic acid anhydride and styrene-maleic acid anhydride that, although giving more complex reaction products with protein in comparison to the previous polymers, convey new and useful properties and in vivo behaviour on the conjugates.