Synthesis and characterization of a pH‐ and glucose‐responsive triblock copolymer via RAFT technique and its conjugation with gold nanoparticles for biomedical applications

Abstract

A combination of ring‐opening polymerization (ROP) and reversible addition of fragmentation chain transfer (RAFT) polymerization techniques was successfully employed for the synthesis of a novel pH‐ and glucose‐responsive thiol‐end‐capped ABC triblock copolymer, namely, poly(acrylic acid)‐block‐poly(vinylphenylboronic acid)‐block‐poly(ε‐caprolactone)–SH (PAA‐b‐PVPBA‐b‐PCL‐SH). The synthesized triblock copolymer was characterized using Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopies. The molecular weights of each segment in the synthesized triblock copolymer were calculated using both gel permeation chromatography (GPC) and 1H NMR spectroscopy. The self‐assembly behavior of the fabricated triblock copolymer under various pHs as well as in the presence of glucose were investigated using dynamic light scattering (DLS) measurement. The PAA‐b‐PVPBA‐b‐PCL‐SH triblock copolymer was conjugated with gold nanoparticles (GNPs). In addition, the morphologies of GNPs, PAA‐b‐PVPBA‐b‐PCL‐SH triblock copolymer, and GNPs@polymer were observed using transmission electron microscopy (TEM). As the results, the fabricated GNPs@Polymer can be employed as drug delivery system and micellar glucose biosensor.