The extent of functionalization on silicon oxide surfaces was characterized by fluorescence microscopy and images are shown in Figure , showing limited fluorescence in the green emission for SOS and SOS-N3, while SOS-Bdpy1 displayed strong green fluorescence confirming successful Bdpy1 conjugation. Also, the images for non-functionalized silicon oxide surfaces in the presence of Bdpy1 (Figure ) reveal the presence of some aggregates lacking uniform adsorption. Fluorescence images were captured from the SOS-Bdpy1 in the absence and presence of GSH (SOS-Bdpy1-GSH), as seen in Figure , with the absence of GSH resulting in strong green emission (λem = 498-531 nm) and no red emission (λem = 565-632nm), while in the presence of GSH, green emission decreased, and red emission appeared, indicating a reaction between GSH and Bdpy1 conjugated on the silicon oxide surface.