VOLTAMMETRIC DETECTION OF DIQUAT AT THE CARBON PASTE ELECTRODE CONTAINING Ca-10(PO4) (6)(OH) (2)

We report a sensitive electrochemical voltammetric method for analyzing diquat (DQ) ions using a carbon paste electrochemical (CPE) modified by porous material, such as hydroxyapatite (HAP). Diquat strongly adsorbed on a HAP-CPE surface and provides facile electrochemical quantitative methods for electroactive DQ ions. Operational parameters have been optimized, and the stripping voltammetric performance has been studied using square wave voltammetry. The peaks current intensity are highly linear over the 7x10(-7)-3x10(-4) mol. L-1 diquat range examined (10 min accumulation time), with a good sensitivity. These findings can lead to a widespread use of electrochemical sensors to detect DQ contaminates. Scanning electron microscopy (SEM) was used for morphology observation and in particular the X-ray diffraction analysis (XRD) and Fourier transformed infrared spectroscopy (FTIR) analysis for characterization of synthesis powder.