A reversible surface functionalized nanowire transistor to study protein–protein interactions

Taking advantage of the reversible association–dissociation between glutathione (GSH) and glutathione S-transferase (GST), we have developed a novel method by surface-functionalizing GSH on silicon nanowire field-effect transistors (SiNW-FET) and then anchoring a particular GST-fused protein for the studies of protein–protein interactions. The reversible surface functionalization method has been proven by analytical techniques, fluorescence imaging, atomic force microscopic imaging, and electrical measurements. The reversible GSH–GST functionality on the SiNW-FET has made this sensorial device consecutively reusable and calibratable, allowing for quantitative analysis. In this work, we have demonstrated that the biologically modified SiNW-FET can be used as a screening sensor for the future studies of biomolecular associations, such as protein–protein interactions, protein–DNA interactions, protein–carbohydrate interactions, etc.