[Absorption spectra study of the association nanoparticle system of berberine-[AuI4]- and its analytical application]

In 0.008 mol x L(-1) HCl medium, [AuCl4]- and I- combine to form [AuI4]-. [AuI4]- reacts with berberine (BB) to form (AuI4-BB) association molecule. The molecules aggregate automatically owing to strong hydrophobic and molecular forces. And (AuI4-BB)n association nanoparticles with orange-yellow color were observed. It exhibits a resonance scattering peak at 520 nm. The absorption peak for the nanoparticle system and the [AuI4]- is at 350 nm. However, the absorbance values for the nanoparticle system increased in the visible light region. Under the conditions chosen, the BB concentration in the range of 0.8 x 10(-6) mol x L(-1)-20 x 10(-6) mol x L(-1) is linear to the A(450 nm) value. The results show that the formation of (AuI4-BB)n nanoparticles produces the resonance scattering effect and the orange-yellow color.