Highly sensitive and reproducible cyclodextrin-modified gold electrodes for probing trace lead in blood

A highly sensitive and reproducible lead sensor based on a cyclodextrin-modi fled gold electrode was created, A self-assembled monolayer (SAM) of thiolated beta-cyclodextrin (6-(2-mercapto-ethylamino)-6-deoxy-beta-cyclodextrin (MEA-P-CD)) was prepared and modified on a gold electrode (MCGE) for specific PP-sensing. Thus the mercury-free sensors for Pb2+ assay based on MCGE were established. A linear calibration response for Pb2+ was found in the range of 1.7 x 10(-8) M to 9.3 X 10(-7) M. The detection limit was 7.1 x 10(-9) M (with S/N > 3), which was 10 times lower than other reported methods of detection Pb2+ with CD. The measurement results via this method for real blood samples were well agree with those obtained by ICP-AES, and thus presented a novel strategy in design of specific lead sensors with high sensitivity and stability for analysis of trace Pb2+ in real blood samples. (C) 2009 Elsevier B.V. All rights reserved.