Chromium(III) ion selective electrode based on glyoxal bis(2-hydroxyanil).

A poly(vinyl chloride) membrane based on glyoxal bis(2-hydroxyanil) as membrane carrier was prepared and investigated as a Cr(III)-selective electrode. The electrode has a linear dynamic range of 3.0x10(-6)-1.0x10(-2) mol l(-1), with a Nernstian slope of 19.8+/-0.5 mV per decade and a detection limit of 6.3x10(-7) mol l(-1). It has a fast response time of <20 s and can be used for at least 3 months without any considerable divergence in potential. The proposed electrode revealed good sensitivities for Cr(III) over a wide variety of metal ions and could be used in a pH range of 2.7-6.5. Above all, the membrane sensor has been used very successfully for the analysis of some food materials and alloys for the determination of Cr(III) ion.