Study on the interaction between glutathione-capped gold nanoclusters (GSH-AuNCs) and bovine serum albumin (BSA) with spectroscopic technique

The interactions of Gold nanoclusters capped with glutathione (GSH-AuNCs) with bovine serum albumin (BSA) have been studied by fluorescence spectroscopic technique at pH 7.4. The quenching constants and binding parameters (binding constants and number of binding sites) were determined by fluorescence quenching method. The obtained results revealed the presence of a static type of quenching mechanism in the binding of GSH-AuNCs with BSA. Based on the thermodynamic parameters extracted from the fluorescence data, it was shown that binding of GSH-AuNCs to BSA was driven mainly by van der Waals and hydrogen bonding interactions. The displacement experiment shows that GSH-AuNCs can bind to the subdomain IIA (site I) of albumin.