Synthesis Of Noble Metal Nanomaterials And Their Application Of Fluorescence Sensing In Biology And Water Environment

The analysis of metal ions are very important in human life.And fluorescent sensors based on the fluorescent metal nanoclusters have attracted wide attention of researchers due to their fastness and low cost.The size of the fluorescent metal nanoclusters is so small that it has chemical properties similar to molecules and good fluorescence properties,which makes the metal nanoclusters have the potential to develop into good fluorescent sensors.In addition,metal nanoclusters have very good biocompatibility,making them suitable for fluorescence sensing analysis in vivo.In this thesis,fluorescence sensing detection method for two metal ions(Al³⁺,Hg²⁺)were proposed using the prepared fluorescent precious mono-/bi-metal nanoclusters.First,a low-fluorescence mono-metal nanoclusters,Au（GSH-Au）NCs was synthesized using reduced glutathione（GSH）as a reducing agent and ligand stabilizer.Based on the aggregation-induced emission,the excessive concentration of Al³⁺can specifically increase its fluorescence nearly40 times,and has a wide concentration detection range（100μM-600μM）.Because Au（GSH-Au）NCs have very good biocompatibility and low toxicity,they have been successfully applied to the fluorescence sensing analysis of excessive Al³⁺concentration in living cells,and have the potential for application in the diagnosis of aluminum poisoning in cells.Next,we used 4,6-diamino-2-mercaptopyrimidine（DAMP）as a reducing agent and ligand stabilizer by“one-pot”to prepare a fluorescent bimetallic nanocluster,DAMP-AuAg BNCs,which has ultra-small size and good colloidal stability in aqueous solution,and can be excited to emit bright red fluorescence.Based on the presence of strongly metalophilic interaction between Hg²⁺and Au⁺,Ag⁺,the fluorescence of DAMP-AuAg BNCs can be specifically quenched by Hg²⁺,which makes it applicable to the fluorescence sensing detection of Hg²⁺.Fluorescent DAMP-AuAg BNCs has a wide detection range（0.85μM-246μM）and low detection limit（20 n M）for the fluorescence sensing detection of Hg²⁺,and has been successfully applied to the fluorescence sensing analysis of Hg²⁺in local tap water and natural lake water environment.Fluorescent bimetallic nanoclusters are superior to their corresponding single-metal nanoclusters in many aspects,and can further explore the application potential of the DAMP-AuAg BNCs in other aspects.