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Abstract

The simultaneous determination of Cd (II), Pb (II), Cu (II), and Hg (II) ions is performed with a disposable screen print carbon electrode (SPCE) modified with a mixture of 3,4-diamine-5:2,5:2-terthiophene (DATT) and graphene oxide (GO). The surface of the modified electrode was characterized with impedance spectroscopy and SEM, and XPS. Experimental variables that affect response signal, such as pH, deposition time, DATT concentration, Nafion® concentration, and GO to DATT ratio were optimized. Interference effects of other heavy metal ions were also tested at various electrolytes. The heavy metal ions are pre-concentrated on the GO-DATT layer by means of complex formation reaction firstly, then electro- deposited. Square wave anodic stripping voltammetry (SWASV) was performed to simultaneously analyze the heavy metal ions by sweeping the potential between -1.3 and +0.5 V after pre-concentration in an acetate buffer solution. Calibration plots using DATT-GO/ Nafion® modified SPCE were obtained for the ions in the concentration range from 0.5ppb to 5ppm. The detection limits for Cd (II), Pb (II), Cu (II), and Hg (II) ions were determined to be ~0.1 ppb.

Biography

Seung-Min Choi received his Bachelor degree in 2014 from the Pusan National University and now he is a Master student in the same University. His research interests include heavy metal ions sensors for chemical and environmental applications.