Gold Nanoclusters Prepared in the Presence of Adenosine Monophosphate and Citrate: Factorial-Based Synthesis Optimization and Sensing Properties

Gold nanoclusters are peculiar objects promising in view of qualitative and quantitative determination of various species, including heavy metal ions and biological molecules. We have recently discovered that introducing sodium azide in the reaction mixture during gold nanocluster synthesis in the presence of citrate and adenosine monophosphate can tune the product emission from blue to yellow. Taking advantage of the factorial design of the experiment, we have optimized the synthesis conditions to obtain pure blue and yellow emitters and investigate their sensitivity to a series of inorganic salts. The experiments have revealed selective quenching of the nanocluster’s fluorescence in the presence of mercury(II) ions.