Dendritic carrier based on PEG: Design and degradation of acid-sensitive dendrimer-like poly(ethylene oxide)s

Abstract

Degradable dendrimer-like PEOs were designed using an original ABC-type branching agent featuring a cleavable ketal group, following an iterative divergent approach based on the anionic ring opening polymerization (AROP) of ethylene oxide and arborization of PEO chain ends. A seventh generation dendrimer-like PEO carrying 192 peripheral hydroxyls and exhibiting a molar mass of 446 k·mol-1 was obtained in this way. The chemical degradation of these dendritic scaffolds was next successfully accomplished under acidic conditions, forming linear PEO chains of low molar mass (≈2k·mol-1), as monitored by 1H NMR, SEC, and MALDI-TOF mass spectrometry as well as by AFM. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.