Preparation And Application Of Cu NCs-based Probes

Copper nanoclusters have received widespread attention because of their good water solubility,excellent luminescence,wide applicability and good biocompatibility and easy availability at low prices.The chemical properties of Cu elements being similar to those of Ag and Au,which are precious metals,makes them a suitable replacement for gold and silver in the preparation of Cu nanoclusters,making them more convenient to obtain and increasing their economic feasibility.This is due to the fact that they belong to the same main group in the periodic table.In recent years,because of their stable chemical properties and easy synthesis methods,precious metals have been widely developed in the field of analysis and testing,while copper nanoclusters have been relatively slow to develop in this field.This is because copper clusters are prone to oxidation and poor stability,and other disadvantages need to be overcome.Therefore,it is important to take copper nanoclusters as a substitute,explore its simple and stable synthesis method and develop its related application research.In this thesis,glutathione-protected copper nanoclusters with high luminescence properties were synthesized and subsequently applied to detect Al³⁺and p H sensing,and a novel electrochemiluminescent biosensor was developed to detect breast cancer susceptibility genes in human serum samples,as follows:1.Glutathione-protected copper nanoclusters（GSH-Cu NCs）were prepared by a one-step redox method using glutathione as a stabilizing template and reducing agent.Transmission electron microscopy（TEM）,ultraviolet-visible absorption spectroscopy（UV）,Fourier transform infrared spectroscopy（FTIR）and steady-state transient fluorescence spectrometry（PL）were employed to characterize the structural and optical properties of glutathione-protected copper nanoclusters,and feasibility analysis was then conducted to verify their properties.It is shown that the copper nanoclusters have both uniform nanometer size and non-agglomeration,as well as stable fluorescence luminescence properties,thus showing great potential for applications.2.Using the finding that aluminum ions can aggregate to induce enhancement of the luminescence intensity of the fluorescence of glutathione-protected copper nanoclusters（GSH-Cu NCs）,a new method of fluorescence sensing platform based on glutathione copper nanoclusters was explored for the detection of aluminum ions,and the enhancement mechanism was further explained.modification of their surface defects.When Al³⁺ions were added to the solution,it caused the aggregation induction（AIE）of GSH-Cu NCs,and thus the fluorescence intensity was changed and appeared to be significantly elevated.A fluorescence response of high quality was observed when Al³⁺concentration was between 1 and 6μM,as evidenced by the F/F₀ signal.Meanwhile,GSH-Cu NCs were found to complete the fluorescence rise and fall with p H value,thus establishing p H sensing.The two methods described above reduced the production cost,facilitated the operation process,and were easy to scale up for popular application.3.Based on the metal ion-induced enhancement mechanism,copper-aluminum nanoclusters（Cu:Al NCs）with high luminescence intensity were prepared as electrochemiluminescent nanoprobes,and the excellent properties of polydopamine（PDA）-mimetic films and cerium dioxide nanoparticles（Ce O₂ NPs）were used to construct an ECL sensor for the successful detection of breast cancer susceptibility genes（BRCA）in clinical serum samples.This study provides a feasible and reliable method for biochemical analysis and clinical detection.