Fig. 2. (A) Particle size distribution of TPE-TETRAD@biotin NPs measured by dynamic light scattering, showing a mean hydrodynamic diameter of 155 nm with a narrow polydispersity of 0.05 PDI. Inset: TEM images of the AIE NPs with different scale bars. (B) Normalized UV-Vis absorption and PL emission spectra of the AIE NPs (red; λ abs = 510 nm, λ em = 680 nm) and TPE-TETRAD nanoaggregates (blue; λ abs = 500 nm, λ em = 675 nm) in water. [TPE-TETRAD] = 10 μM; [TPE-TETRAD@biotin] = 6 μg mL–1; λ ex = 488 nm.
