Generation of helical multi-functional microfiber motors based on modified microfluidic spinning method

Due to unique asymmetric shapes and easily realized directional movements, helical micromotors are widely used in applications such as drug delivery, cell manipulation, and wastewater purification. However, most of the hydrogel helical microfiber motors were water-based and had a homogeneous polymer network structure, which limited their practical applications like drug release. In this study, an emulsion-based microfluidic spinning method was used to prepare heterogenous helical hydrogel microfiber motors. Fine oil-in-water (O/W) emulsions were used as the inner phase of the microfluidic spinning process. When dichloromethane was used, micromotors with porous structure were formed after solidification and volatilization, improving the catalytic degradation rate of pollutants in water treatment application. When soybean oil was used, fat-soluble drugs were encapsulated successfully and gradually released as the micromotor degraded. Besides, the diameter and pitch size of the prepared fibers could be easily adjusted, and mass manufacturing (>100 m) was achieved.