Hydrogel-Based Microactuators with Remote-Controlled Locomotion and Fast Pb2+-Response for Micromanipulation

Hydrogel-based microactuators that enable remote-controlled locomotion and fast Pb2+-response for micromanipulation in Pb2+-polluted microenvironment have been fabricated from quadruple-component double emulsions. The microactuators are Pb2+-responsive poly(N-isopropylacrylamide-co-benzo-18-crown-6-acrylamide) microgels, each with an eccentric magnetic core for magnetic manipulation and a hollow cavity for fast Pb2+-response. Micromanipulation of the microactuators is demonstrated by using them for preventing Pb2+-leakage from microchannel. The microactuators can be remotely and precisely transported to the Pb2+-leaking site under magnetic guide, and then clog the microchannel with Pb2+-responsive volume swelling to prevent flowing out of Pb2+-contaminated solution. The proposed microactuator structure provides a potential and novel model for developing multifunctional actuators and sensors, biomimetic soft microrobots, microelectro-mechanical systems and drug delivery systems.