Microscale hydrogels for medicine and biology: Synthesis, characteristics and applications

Microscale hydrogels with dimensions of 200 mu m or less are powerful tools for various biomedical applications such as tissue engineering, drug delivery, and biosensors, due to their size, biocompatibility, and their controllable biological, chemical, and mechanical properties. In this review, we provide a broad overview of the approaches used to synthesize and characterize microgels, as well as their applications. We discuss the various methods used to fabricate microgels, such as emulsification, micromolding, microfluidics, and photolithography. Furthermore, we discuss the effects of porosity and crosslinking density on the mechanical and biological properties of hydrogels. In addition, we give specific examples of the use of hydrogels, such as scaffolds and cell encapsulation for tissue engineering, controlled release materials for drug delivery, and environmentally sensitive sensors for microdevices. Finally, we will discuss the future applications of this technology.