Progress on synthesis and applications of nanogold-based composite hydrogels

Nanogold tends to aggregate and then loses its excellent performance due to the high surface energies. Hydrogels with porousness and adjustable structures have been widely utilized in supporting and stabilizing of nanogold. The nanogold-based composite hydrogels combine excellent physical and chemical properties of both gold nanogold and hydrogels. It is a potential research field that can meet diversified applications. In this paper, the synthesis methods and properties of some representative nanogolds (gold nanoparticles, gold nanorods, gold nanocages, etc.) are firstly summarized. Then, the preparation of nanogold based hydrogels and the functional applications in biomedical engineering, catalysis and sensing are reviewed. Finally, the future research directions are outlooked.