The experimentalwork included (i) the determination of solvatochromic shifts in absorptionand emission spectra, (ii) the determination of the excitation andemission spectra of bTVBT4 bound to tau, and (iii) the presentationof fluorescence images of the brain section from patients diagnosedwith Alzheimer’s and Pick’s diseases as to address thespecificity in the bTVBT4 binding. Here, MAPT is linked to frontotemporal dementia.