Fabrication of nanogels for delivery of molecules

Recently, nanogels have been extensively studied as a means to deliver bioactive molecules such as drugs, proteins, and vaccines due to their versatile and unique properties such as high water absorption, easy production, surface modification, high stability and biocompatibility. Various materials including natural polymers, synthetic polymers, peptides, and proteins have been selected for fabrication of nanogels to achieve a targeted, sustained, or protected delivery depending on biomedical applications and bioactive molecules. This review describes a variety of nanogel fabrication for applications in molecular delivery systems. The detail of materials and approaches for preparation of nanogels will be discussed, including free radical polymerization, controlled/living radical polymerization, self-assembly, and metal/nanogel composites.