Dual-responsive nanoparticles constructed using light- and redox-responsive linkages

Abstract

Stimuli-responsive nanoparticles have garnered significant interest for advanced materials design and development in areas such as biomedicine, sensing, and energy. Recent studies have demonstrated that integrating multiple functionalities into a single nanoparticle structure is a crucial approach for engineering multi-responsive properties. In this study, light- and redox-responsive nanoparticles were synthesized using a simple one-pot emulsion polymerization utilizing mild thiol-disulfide exchange reactions to direct the self-assembly process. Poly(disulfide) bonds were formed during this process and comprised the core part of the nanoparticles, enabling redox responsiveness upon disulfide cleavage. A photochromic diarylethene (DAE) was also covalently attached within the hydrophobic poly(disulfide) matrix, imparting light-responsive behavior to the particles. Tuning the nanoparticle composition by varying the thiol/DAE ratio enabled a correlation between particle composition and disassembly kinetics to be established. The DAE retained photochromic activity in the nanoparticles, however, the switching efficiency was diminished when compared to the monomer due to the matrix effect.