An electrochemical sensor for stripping analysis of Pb(II) based on multiwalled carbon nanotube functionalized with 5-Br-PADAP.

The present study serves to focus attention on the modification of multiwalled carbon nanotube with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) and its application for the development of a new, simple, and selective modified electrode in order to determine Pb(II) in standard alloys and water samples. The electrochemical method was based on open circuit accumulation of lead ions onto a 5-Br-PADAP-modified multiwalled carbon nanotube electrode and then their anodic stripping voltammetric determination. The linear range for Pb(II) ions was from 0.9 to 114.6 μg L. The detection limit and relative standard deviation were found to be 0.1 μg L and 1.6%, respectively. This method demonstrates the powerful application of carbon nanotubes in the field of mercury-free electrodes in voltammetric stripping analysis. [ABSTRACT FROM AUTHOR]