Research progress and application prospect of engineered small extracellular vesicles.

Extracellular vesicles (Evs) act as a natural intercellular message transmitter, Evs can carry proteins, ribonucleic acid (RNA) and other bioactive substances, and have rich biological regulatory functions. Because of its low immunogenicity and high biocompatibility, it has become a popular research object in drug delivery. These remarkable properties also create new opportunities for modern therapy. However, due to the complex preparation process, there are challenges in terms of targeting accuracy, load release controllability, and pharmacokinetic optimization, and many problems may be encountered in reality. Based on real-life biomedical experiments, this paper summarizes the methods and types of Evs loading drugs, membrane modification methods, and the use of biological materials to improve the release efficiency, so as to provide reference for future research on engineered Evs.