Preparation Of Chelating Polymer Modified Electrode For Determination Of Heavy Metal Ions

Gclycidyl methacrylate polymer (PGMA) brushes were prepared usingelectrochemical mediated atom transfer radical polymerization(eATRP) at awaxed graphite electrode(WGE), Then a ring-opening reaction of the epoxygroups was enforced in situ using iminodiacetic acid (IDA) with the formationchelating polymer brushes (IDA/PGMA/WGE). The electrode was carefullyexamined by fourier transform infrared spectroscopy, field emission scanningelectronmicroscope, and electrochemistry techniques. The results showed that agreat deal of polymer brushes could be observed at IDA/PGMA/WGE. FurtherIDA/PGMA/WGE was successfully used for the determination of Pb(II) bydifferential pulse adsorptive anodic stripping voltammetry. The currentresponses were linearly increased depending on the concentration from3×10-9～1×10-7mol/L (limit7.9×10-10mol/L,3σ).Melamine-formaldehyde-thiourea chelating polymer (MFT) was prepared byultrasonic method. MFT/multi-walled carbon nanotube (MFT/MWCNTs)composite modified waxed graphite electrode (MFT/MWCNTs/WGE) wasprepared through coating method, and characterized by field emission scanningelectron microscope and electrochemical techniques. The results showed that thechelating polymer could be uniformly dispersed by MWCNTs at the electrode.The electrode was successfully applied to Pb(II), Cd(II) screening. The stripingpeak current shows a good linear relationship in the concentration range of3×10-8～9×10-7mol/L for Pb(II)and5×10-8～7×10-7mol/L for Cd(II), with adetermination limit of2×10-9and3×10-9mol/L(3σ) for Pb(II) and Cd(II),respectively.