Fig. 6
The SPR spectra of AgNPs in aqueous solutions of the different concentrations of CTAB (a) and plot of the absorbance intensity of AgNPs as a function of molar concentration of CTAB at 410 nm (b). Conditions: conditions as in Fig. 1 except 2.0-mL K2HPO4 buffer solution (pH 9.5); appropriate volumes of CTAB solutions of (a) 0.0, (b) 0.2, (c) 0.4, (d) 0.6, (e) 0.8, (f) 0.9, (f) 1.0, (g) 1.2, (h) 1.4, and (i) 1.6 mmol L−1