Modified carbon paste ion selective electrode for determining Cr(<scp>iii</scp>) ions in aqueous solutions and some real samples using tetragonal zirconia nanoparticles

Abstract

of Cr(iii) ions. The built-in sensor displayed a quick response time (7 s), was highly thermally stable in the range of 10 to 60 °C without departing from Nernstian behaviour and could be used for about 60 days in the pH range of 2.0 to 6.0. The electrode demonstrated excellent selectivity for the Cr(iii) ion towards a variety of metal ions. For chromium ion determination, numerous spiked real samples, including honey, water, tea, coffee, milk, cheese, and cosmetics, were used. Validation methods were used, and the results showed that there is no significant difference between the two methods (ICP and ISE) at a 95% confidence level. In several real water samples, the estimated limits of detection, limits of quantification, percent recovery, standard deviation, and relative standard deviation showed the effectiveness of the proposed electrode in the potentiometric detection of Cr(iii) ions.