Poly(glutamic acid): Production, composites, and medical applications of the next-generation biopolymer

Numerous biopolymer-based functional composites have been developed for medical applications. Poly(glutamic acid) (PGA) is an amino acid biopolymer that has recently attracted attention due to its biocompatibility, non-immunogenicity, and biodegradability. PGA and its composites have been studied to improve their function as medical materials. This review briefly introduces chemically and microbiologically synthesized PGA. In addition, this article provides general and advanced preparation methods for various PGA-based composites, including hydrogels, nanofibers, monoliths, and nanoparticles. Furthermore, it covers recent advances in PGA-based functional composites for medical applications, such as active antimicrobial materials as well as the use of PGA composites for vaccine adjuvants, cancer therapy, medical devices, and tissue regeneration. Anticancer agent delivery and cancer immunotherapy are included in the PGA-based cancer therapy system section. Barrier membranes and stent applications are summarized within the medical devices section. Furthermore, various tissue regeneration topics are introduced, including applications in wound healing, as well as the tissue-specific regeneration of bone, cartilage, intervertebral discs, corneas, kidneys, and neurons. In summary, this is an overview of the various challenges of using PGA and the scope of emerging research.