Abstract��Nanogels combine the advantages of hydrogels and nanoparticles, such as small particle size, prolonged blood circulation time, biocompatibility, biodegradation and high drug loading. Common carrier materials is used for the preparation of nanogels include polyacrylic acid, polyacrylamide, pluronic, polysaccharide and their derivates. They can be cross-linked based on amine reaction, ��click�� chemistry, photo-induced cross-linking, physical cross-linking or heterogeneous polymerization of monomers to form nanogel carrier systems. Nanogels, as ideal and novel drug delivery systems, have great promise in the delivery of chemotherapeutic drugs, proteins and genes.The carrier materials, preparation methods and applications of nanogels were reviewed based on relevant articles published in recent years.
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