Synthesis Of Novel Fluorescent Nanocluster Probes And Their Applications In Biological And Environmental Analysis

Fluorescent nanoclusters have excellent optical properties and biocompatibility and also have wide applications in the fields of fluorescence sensing,quantitative analysis,and biomedicine.In recent years,with the development of novel metal nanoclusters,ordinary transition metal nanoclusters,non-metallic nanoclusters and other fluorescent probes,the preparation and applications of high-performance and low-cost fluorescent nanoclusters have become a research hotspot in this field.In this paper,metal nanoclusters and carbon nanoclusters with good fluorescence properties were synthesized by a simple and rapid method,which realized the sensitive detection of thiol pollutants and ascorbic acid,respectively.The main research content of this paper is as follows:Chapter 1: The basic situation of metal nanoclusters and carbon nanoclusters is briefly introduced,and the synthesis methods and practical applications of metal nanoclusters and fluorescent carbon nanomaterials are also reviewed.Chapter 2: Thiol compounds have strong odor,which not only seriously pollutes the environment but also threatens human health and quality of life.In this study,a novel triplet induced fluorescent “turn-off” strategy was designed for the detection of thiol pollutants via a glutathione-stabilized copper nanoclusters(GSH-Cu NCs)probe.The as-prepared GSH-Cu NCs not only have small size and good water-solubility,but also exhibit a strong red-emitting fluorescence at 630 nm,which could be quenched quantitatively with the increase of the thiol pollutants.This method was successfully applied to detect the above thiol pollutants in lake water with good recoveries.Furthermore,its further application was also expanded as the luminous test strips based on the fluorescent characteristic of GSH-Cu NCs for fast detection of thiol pollutants.Chapter 3: In this work,a contact route was established for synthesis of fluorescent carbon nanomaterials by directly mixing polyethyleneimine(PEI)solution with ascorbic acid(AA)at room temperature.They not only have small size and good water-solubility,but also exhibit a strong fluorescent emission at 516 nm.Besides,the fluorescent intensity of the as-prepared CNCs could be quantitative enhanced with the increase of AA adding.Based on this phenomenon,these CNCs were developed as a sensitive “naked-eye” probe to determinate AA via a “turn-on” method with a low limit of detection 0.15 ?M in the linear range from 0.5 to 100 ?M.This new method was also successfully applied to detect AA in human serum and cherry tomato samples with the recoveries ranged from 97% to 105%.Interestingly,its further application was also expanded as biocompatible and green fluorescent ink for information encryption,and information storage.Chapter 4: We summarized the results of these two fluorescent probes in analytical detection in this paper and prospected the future development.