Development of a New Modified Screen-Printed and Carbon Paste Electrodes for Selective Determination of Cetyltrimethylammonium Bromide in Different Water Samples

Cetyltrimethylammonium bromide (CTAB)-selective electrodes of the types carbon paste (CPE) and screen-printed sensors (SPE) based on incorporation of zeolite ionophore have been constructed. The influences of paste composition, temperature, pH of the test solution, and foreign ions on the electrodes performance were investigated. The electrodes showed Nernstian behavior with linear concentration range of 4.61 x 10(-7) -1.0 x 10(-2) and 1.26 x 10(-7) -1.0 x 10(-2) mol L-1, slope of 57.56 +/- 1.25 and 58.92 +/- 0.27 mV decade(-1) and lower limit of detection of 4.61 x 10(-7) and 1.26 x 10(-7) mol L-1 for modified CPE and SPE sensors, respectively. The electrodes display good selectivity for CTAB with respect to a number of common foreign inorganic and organic species. The response is not affected by pH variation between 2.0 - 8.5 and 2.0 - 9.0 for modified CPE and SPE, respectively. The sensors were successfully used for determination of CTAB both in pure solution and in different spiked real water samples. The frequently used CTAB of analytical and technical grade as well as different water samples has been successfully titrated and the results obtained agreed with those obtained with standard two phase titration method. The sensitivity of the proposed method is comparable with the official method and ability of field measurements.