Fig. 1b shows the effect of varying chloroauric acid concentrations
on nanoparticle synthesis.Apurplish-pink color was observed
with 1.0mMconcentration of the gold salt [Fig. 1b (A)]. This is consistent
with the visual observations made in Fig. 1a (B) wherein,
the reaction mixture composition was similar (10mg BPE, 1.0mM
chloroauric acid, pH 3.0). The UV–vis spectra of the tubes also displayed
a peak in range of 510–600 nm.With 0.5, 0.25 and 0.125mM
of gold chloride, varying shades of purple were observed [Fig. 1b
(B–D)].