Recent advances in the microfluidic generation of shape-controllable hydrogel microparticles and their applications

Hydrogel microparticles, generally accepted as significant green materials, have been widely used in chemical, biological, and biomedical fields owing to their excellent biocompatibility, biodegradability, and non-cytotoxicity. Among these, non-spherical hydrogel microparticles with diverse shape anisotropy have great potential in applications such as drug delivery, cellular interaction, micromotors, etc. Benefiting from their shapes, their functionalities in such fields cannot be satisfied by the typical spherical types. Recently, microfluidics with precise control and domination of fluids at microflow sizes has emerged as a powerful method for synthesizing shape-controllable hydrogel microparticles with good monodispersity and unique morphology. In this review, we tried to provide an overview of the production of non-spherical microparticles composed of green hydrogel materials, emphasizing the microfluidic approaches. Furthermore, a brief introduction to their current applications is also presented.