New Syntheses of Branched, Multifunctional High-Molecular Weight Poly(ethylene glycol)s or (MultiPEG)s

Abstract

A new set of branched high-molecular weight multifunctional poly(ethylene glycol) (MultiPEG) derivatives was obtained from smaller commercial diOH-PEGs (M.W. = 2000 and 6000 Da) which were selectively monoprotected, properly activated at the residual OH-functions and treated with 1,3-diamino-2-propanol and 2-amino-1,3-propandiol as polyfunctional linkers. They were purified by molecular exclusion chromatography or extensive dialysis and characterized by GPC and 1 H-NMR. The final polymeric derivatives are characterized by a higher number of terminal reacting moieties (up to 6 times) than that found in linear, commercial PEGs of same molecular size. This increased loading capability can be applied to improve their use as drug carriers and soluble synthetic supports.