Abstract

Microfluidic Preparation of Flexible Micro-Grippers with Precise Delivery Function

Yu Hao Geng, First Author, The State Key Lab of Chemical Engineering, Department of Chemical Engineering, Tsinghua University

Here in this study, we used the microfluidic technology for preparing gas-liquid Janus emulsions, and firstly proposed a one-step preparation method of micro-gripper, which can be regarded as a micro-robot with simple delivery function, and then characterized the behavior of oriented and precise delivery. With the enrichment of the Fe3O4 nanoparticles, the micro-gripper can reach a speed of 1.5 mm/s driven by a magnetic field. The micro-gripper’s body is made of Poly(N-Isopropylacrylamide) hydrogel, a reversible temperature-responsive polymer. The thermo-sensitivity of hydrogels offers the function of grasping, to closely integrate with the target carried, ensuring the stability of the carrying process. The reversible variation of the hydrogel allows the micro- gripper to be reusable and having a long shelf life. The preparation of micro-grippers and the hydrophilic and hydrophobic transition of hydrogels were first realized on the basis of the gas-liquid Janus emulsion template, and the water-soluble drugs could also be loaded on them to achieve targeted drug release.