Study On The Interaction Of GSH And DHLA Modified Ag Nanoclusters With DNA/HSA

Over the past decade,silver nanoclusters(Ag NCs)have been used in a wide range of applications in biomedicine,drug therapy and cellular imaging due to their unique electronic structure and a variety of excellent properties,and have attracted great interest from researchers from all walks of life.DNA is one of the most important biomolecules,containing all the genetic material that encodes the information required for biological development.Human serum albumin(HSA)is a common protein in the circulatory system and plays a vital role in the transport of fatty acids,metal ions,steroids and drugs through the blood to cells and tissues.Both are biomacromolecules that are essential for the body to maintain life activities and their importance.And the mechanisms of drug-biomolecule interactions are now being increasingly studied,yielding numerous undoubtedly important discoveries,such as timely warnings of harmful substances that can explain most of the biological mechanisms or provide important clues for the targeted development of new chemotherapeutic drugs.Therefore,in order to realize the applications of Ag NCs in the fields of biomedicine,drug therapy and cell imaging,it has become particularly important to investigate the interaction mechanisms between Ag NCs and biomolecules.In this thesis,the mode of interaction between Ag NCs and calf thymus DNA(ct DNA)/ HSA,the mechanism of burst inactivation,the site of action,the binding strength and the effect on the conformation of the two biomolecules were investigated by various spectroscopic methods combined with non-spectroscopic methods such as viscosity,electrochemical methods and molecular docking technique to provide a reference for the preparation and application of Ag NCs.Chapter 1: The preparation methods,properties and applications of Ag NCs are described.The structure and role of DNA and protein in human life are introduced.Chapter 2: The reasons for choosing glutathione(GSH)and dihydrolipoic acid(DHLA)as ligands for the synthesis of Ag NCs are explained.The preparation schemes of two Ag NCs,GSH-Ag NCs and DHLA-Ag NCs,are introduced,and characterised by various means such as UV spectroscopy,fluorescence spectroscopy,TEM,XPS and FT-IR spectroscopy,and the successful preparation of the two Ag NCs,and their quantitative analysis were carried out.Chapter 3: The interactions between two Ag NCs,GSH-Ag NCs and DHLAAg NCs,and ct DNA were mainly explored from abstraction to visualisation.The binding mode,quenching mechanism,binding strength and influence on the conformation of ct DNA between the two Ag NCs were determined by spectroscopic methods,viscometry and molecular docking technique.Chapter 4: The interactions between two Ag NCs,GSH-Ag NCs and DHLAAg NCs,and HSA were mainly explored.The interaction sites,quenching mechanism,binding strength and effects on HSA conformation between the two Ag NCs and HSA were determined by various fluorescence spectroscopy,circular dichroism spectroscopy and molecular docking technique.Chapter 5: This chapter concludes with a summary of the full study and experimental results,and provides an outlook for future improvements in the synthesis of Ag NCs.