Glucose-Sensitivity of Boronic Acid Block Copolymers at Physiological pH

Abstract

Well-defined boronic acid block copolymers were demonstrated to exhibit glucose-responsive disassembly at physiological pH. A boronic acid-containing acrylamide monomer with an electron-withdrawing substituent on the pendant phenylboronic acid moiety was polymerized by reversible addition–fragmentation chain transfer (RAFT) polymerization to yield a polymer with a boronic acid p<i>K</i>_a = 8.2. Below this value, a block copolymer of this monomer with poly­(<i>N</i>,<i>N</i>-dimethylacrylamide) self-assembled into aggregates. Addition of base to yield a pH > p<i>K</i>_a or addition of glucose at pH = 7.4 resulted in aggregate dissociation that may prove promising for controlled delivery applications under physiological relevant conditions