Multi-Stimuli Sensitive Amphiphilic Block Copolymer Assemblies

TLDR

Stimuli‑responsive polymers are widely regarded as promising systems for diverse biomedical applications. The study reports a novel triple‑stimuli‑sensitive block copolymer assembly that responds to temperature, pH, and redox changes. The assembly is constructed from an acid‑sensitive THP‑protected HEMA core linked via a disulfide bond to a temperature‑responsive PNIPAM shell, and its micellar behavior and guest‑release kinetics were characterized under single and combined stimuli. Combined stimuli enable fine‑tuned release kinetics and potential location‑specific delivery of encapsulated guests.

Abstract

Stimuli-responsive polymers are arguably the most widely considered systems for a variety of applications in biomedical arena. We report here a novel triple stimuli sensitive block copolymer assembly that responds to changes in temperature, pH and redox potential. Our block copolymer design constitutes an acid-sensitive THP-protected HEMA as the hydrophobic part and a temperature-sensitive PNIPAM as the hydrophilic part with an intervening disulfide bond. The micellar properties and the release kinetics of the encapsulated guest molecule in response to one stimulus as well as combinations of stimuli have been evaluated. Responsiveness to combination of stimuli not only allows for fine-tuning the guest molecule release kinetics, but also provides the possibility of achieving location-specific delivery.