Analytical Sciences


Abstract − Analytical Sciences, 18(4), 449 (2002).

Detection of Ni2+ by aDimethylglyoxime Probe Using Attenuated Total-Reflection InfraredSpectroscopy
Thomas PONNUSWAMY and OliverCHYAN 
University of North Texas, Department ofChemistry, Denton, TX 76203, USA
A new analytical approach for the detectionof Ni2+ utilizing an attenuated total reflection (ATR) techniqueis discussed in this paper. Nickel detection was accomplished on a siliconATR parallelogram crystal uniformly coated by a ca. 1.5-um Nafionfilm embedded with dimethylglyoxime (DMG) probe molecules. The detectionof Ni2+ is based on the appearance of a unique infraredabsorption peak at 1572 cm-1 that corresponds to the C=Nstretching mode in the nickel dimethylglyoximate, Ni(DMG)2,complex. The suitable operational pH range for the nickel infrared sensoris between 6 - 8. High alkalinity in the sample solution causes a leachingof Ni(DMG)2. The detection limit of the nickel infrared sensoris 1 ppm in a sample solution of pH = 8. Interference studies revealedthat Cu2+ could compete with Ni2+ for the DMG sitesin the Nafion matrix. The new nickel detection methodology can bepotentially utilized, after further improvement, in field analysis tolocate hot spots contaminated with a high ppm of Ni2+.