Phototactic Poly(N-isopropyl acrylamide) Microgels with Photoresponsive Property

Smart functional microgels hold great potential in a variety of applications, especially in drug transportation. However, current drug carriers based on physiological internal stimuli cannot efficiently orientate to designated locations. Therefore, it is necessary to introduce the self-propelled particles to the drug release of the microgels. In order to study self-propulsion of microgels induced by light, it is also a challenge to prepare micron-sized microgels so that they can be observed directly under optical microscopes. In this work, phototactic microgels with photoresponsive properties are prepared. The microgel particles can be observed by confocal laser scanning microscopy. The photoresponsive properties of microgels are fully investigated by various instruments. Light can also regulate the state of the microgel solution, making it switch between turbidity and clarity. The phototaxis of particles irradiated by UV light was studied, which may be used for microgels enrichment and drug transportation and release.