Precise blood lead analysis using a combined internal standard and standard addition approach with disposable screen-printed electrodes.
We report here a highly accurate and efficient method for blood lead analysis (BLA) through the use of a disposable electrode. A new type of mercury-plated preanodized screen-printed carbon electrode, together with a thallium(III) internal standard, simplifies calibration and gives easily quantifiable signals for accurate BLA. A preanodization procedure improves the preconcentration ability of the working electrode through the effect of lead (Pb) complexing with an electrogenerated surface functional group, mainly >C=O. Under optimized conditions, the ratio of the anodic stripping peak currents of Pb and Tl (i.e., i(Pb)/i(Tl)) is linear against [Pb] in the window of 1-300 ppb with a correlation coefficient and detection limit (signal-to-noise ratio=3) of 0.999 and 0.23 ppb, respectively. This approach was used to analyze blood samples (n=55) from workers at a local battery factory. The results are consistent with those obtained from graphite furnace atomic absorption spectroscopy and confirm the applicability of the proposed method.
Yang
Chih-Chio
CC
Department of Chemistry, National Chung Hsing University, Taichung 402, Taiwan.
Kumar
Annamalai Senthil
AS
Zen
Jyh-Myng
JM
D002244:Carbon / Q000737:chemistry; D003217:Conductometry / Q000379:methods / Q000592:standards*; D004566:Electrodes; D006801:Humans; D007854:Lead / Q000097:blood*; D008628:Mercury / Q000737:chemistry; D012015:Reference Standards; D013793:Thallium / Q000097:blood
D007854:Lead; D002244:Carbon; D013793:Thallium; D008628:Mercury