Selectivity Determination of Pb^2+ Ion Based on TiO_2-Ionophores BEK6 as Carbon Paste ElectrodeComposite

Pb^2+ ion was investigated by voltammetry selectivity using tio_2-ionophores hexa(p-tert butyl)hexa(ethyl ester)calix[6]arene (bek6) composite to increase the selectivity and sensitivity of carbon paste electrode (cpe). the bek6 was synthesized by using hydrolysis method, meanwhile the tio_2-p25 and graphite powder were mixed as an electrode composite. the scanning electron microscopy (sem) shows that the cpe doped tio_2-bek6 (cpe/tio_2-bek6) have morphology likes a rough, non-porous, composed of fine particles, and homogeneously. the presence of pb^2+ ion in ph 5 citrate buffer electrolyte causes the peaks appearance on epa and epc were 0.17 v and 0.37 v with the peak potential current generated of 15.15 μa and -12.0 μa, respectively. the 0.005 g bek6 was increased significantly the peak current of the pb^2+ ion with the lod value of 0.1756. in addition, the presence of tio_2-bek6 composite shows the measurement current stability by %rsd of 0.83.