Abstract
A Nafion/ionophore, 4-tert-butylcalix[4]arene-tetrakis(N,N-dimethylthioacetamide) composite coated and bismuth film modified glassy carbon electrode. (GC/NA-IONO/BiFE) was described to determine trace lead sensitively and selectively. The characteristics of such modified GC/NA-IONO/BiFE were studied by scanning electron microscopy and cyclic voltammetry. The influence of various experimental parameters upon the stripping lead signal at the GC/NA-IONO/BiFE was explored. Under the optimized conditions, the differential pulse voltammetric stripping response is highly linear over the 0.1–8.0 nM lead range examined (180 s preconcentration at −1.2 V), with a detection limit of 0.044 nM and good precision (RSD = 5.4% at 0.5 nM). Also applicability to seawater samples was demonstrated at such modified electrode. The high selectivity of ionophore coupled with the excellent electrochemical characteristics of bismuth endow the GC/NA-IONO/BiFE a promising and robust tool for monitoring of trace lead rapidly and precisely.
This work was financially supported by the Chinese Academy of Sciences (KZCX2-YW-410), the National Natural Science Foundation of China (40776058), the National 863 High Technology Project of the Ministry of Science and Technology of China (2007AA09Z103), the Department of Science and Technology of Shandong Province (2006GG2205033) and the Outstanding Youth Natural Science Foundation of Shandong Province (JQ200814).
Notes
a Average value of 3 determinations ± standard deviation
b Average value of 5 determinations ± standard deviation