Abstract:

This study aimed to improve the sensitivity, stability, accuracy and safety of the electrochemical sensor
for lead (Pb2+). The screen-printed carbon electrode (SPCE) was modified with carbonated hydroxyapatite to
accumulate Pb2+ efficiently, ionic liquid [BMIM]PF6 to improve electrical conductivity, and Nafion membrane
to increase the sensitivity and stability. Thus, we established an environmental-friendly and multiple sensitive
electrochemical sensor for rapid determination of trace lead. Under optimized experimental conditions, the signal
peaks of square-wave stripping voltammetry had a linear relationship with Pb2+ concentrations in the range from
3 to 600 μg/L, with a detection limit of 0.37 μg/L (RSN = 3). The relative standard deviation (RSD) of the sensor
was 3.4% (n = 8). The results determined by this method were similar to those determined by ICP-MS. The
electrochemical sensor developed in this study proved environmental-friendly, sensitive, accurate, economic and
convenient.

Key words: carbonated hydroxyapatite (CHA), elecrtrochemical sensor, lead, tea