The increase in
anodic current at the electrode which was modified with Tu-SBA-
15 demonstrates that phenylthiourea which was directly bonded
on SBA-15 plays an important role in the accumulation process of
Ag(I) on the electrode surface. As seen in Fig. 1, the signal obtained
for 40 pM Ag(I) at bare CPE is relatively high. Previously, Jacobs [24]
reported that the anodic stripping voltammetriy can be used for
the determination of as little as 0.25 ppb of silver at a bare carbon
paste electrode.