Carbon composite-PVC based membrane coated platinum electrode for chromium determination

A new synthesized 1-(2-(1H-imidazole-1-yl)-1-(4-methoxyphenyl)ethylidene)-2-phenyl hydrazine has been used as an ionophore in carbon composite-PVC coated platinum electrode for fabrication of chromium(III)-selective sensor. The homogenization procedure of membrane mixture was performed by applying of the ultrasound in this respect. The sensor shows a good Nernstian slope of 19.62 ± 0.45 mV decade−1 in a wide linear range concentration of 8.4 × 10−8-1.0 × 10−2 M and a detection limit of 6.8 × 10−8 M for Cr(NO3)3. The proposed electrode has a short response time of about 10 s and is reproducible and stable for a period of at least 2 months. The performance of the sensor is pH independent in the pH range of 3.3-5.9 and it also works well in partially non-aqueous medium. The electrode has good selectivity relative to variety of metal ions. The practical analytical utility of the electrode is demonstrated by measurement of Cr(III) quantitatively in multivitamin, mineral water and also as an indicator electrode in the potentiometric titration of chromium (III) against EDTA.