| Noble metal nanoclusters are kinds of nanomaterials,consisting of several to tens of atoms.The nanoclusters have advantages of ultra-small size,good optoelectronic performance,stability and biocompatibility,and have a wide range of applications in analytical sensing,catalysis,bioimaging and labeling.Among them,silver nanoclusters have become a research hotspot in the field of analytical sensing because of their good stability and low cost.In addition,silver nanoclusters also have good development prospects in the field of antibacterial,because silver is a natural antibacterial metal.In this paper,a highly sensitive and selective active oxygen sensing method was established by synthesizing water-soluble fluorescent silver nanoclusters.The silver ions on the surface of silver nanoclusters were used in the field of sterilization to effectively kill bacteria.Chapter 1 is a brief introduction of the types and detection methods of reactive oxygen species.Further,the synthesis and application of silver nanoclusters and the development status of nano silver material antibacterial agents were discribed.In chapter 2,the stable water-soluble thermal-emitting water-soluble fluorescent silver nanoclusters,were synthesized by hydrothermal method with PMAA and PVP as templates and protective agents,respectively.It is found that silver nanoclusters have good selectivity to common reactive oxygen species,ClO-,1O2,·OH,and can be used for detection in real samples.The limits of detection are 0.44 μmol L-1,0.64 μmol L-1 and 0.52 μmol L-1,respectively.The antioxidant capacity of the skin care product was evaluated by this method,and the concentration of ClO-in the real water sample was examined.In chapter 3,the surface of water-soluble silver nanoclusters synthesized by hydrothermal method is rich in silver ions and silver ions have a good application prospect in the killing of bacteria.Escherichia coli(E.coli O157:H7)and Staphylococcus aureus(S.aureus)are the target bacteria.E.coli O157:H7 is treated with 150 ng mL-1 of silver nanoclusters under 10 min with a killing rate of 100%.And S.aureus is treated with 500 ng mL-1 of silver nanoclusters under 20 min with a killing rate of 100%.The toxicity of silver nanoclusters to various cells was investigated.The results showed that silver nanoclusters were not toxic to cells.Therefore,silver nanoclusters could be used as a new antibacterial nanomaterial for intracellular sterilization. |
