Figure 3
Characterization of the GNPs. Top: UV–vis Spectroscopy of bare GNPs, MDDA coated GNPs and MDDA + Barbiturate coated GNPs, for 20 nm GNPs. An expanded signal was observed following each layer of coating, confirming the chemical coating. Bottom: zeta-potential measurements at the various stages of GNP coatings for each GNP size. The significant difference obtained (both by zeta-potential and UV–vis Spectroscopy) following each chemical step demonstrates the efficiency of the chemical coating.