A new chelation induced enhanced fluorescence-type optical sensor based on parared immobilized in a plasticized PVC membrane for selective determination of Zn(II) ions

A new optical sensor based on fluorescence enhancement of a disperse azo dye (parared, PR) immobilized in a plasticized PVC membrane for the determination of Zn2+ ions has been developed. The optode displays a calibration response for Zn2+ ions over the concentration range of 5.0 × 10−3–1.0 × 10−6 M. The response characteristics of the sensor including its response mechanism, membrane composition, pH of solution, repeatability and reproducibility, response time, regeneration and selectivity are discussed in detail. The optode was applied as an indicator electrode in titration of zinc ions and also to the determination of zinc in zinc sulfate tablets and zinc oxide cream.