Fabrication of a new magnesiun-ion selective electrode (Mg-ISE) based on photopolymer of poly(Tetrahydrofurfuryl Acrylate)(pTHFA) thin-films

Abstract

This study has succeeded in fabricating Magnesium-ion selective electrode (Mg-ISE) using membrane poly (Tetrahydrofurfuryl acrylate) (pTHFA) synthesized by photopolymer technique. In this study, several experiments have been carried out which included optimization of pTHFA composition, performance testing of the Mg-ISE sensor, selectivity testing, pH effects and validation using real samples. Validation testing has been done by comparing the test results of the Mg-ISE sensor with the standard method using titration techniques. In the optimization study, the optimum composition of 1:1 mol ratio (KTpClPB/Ionophore) was obtained, where the KTpClPB used was 1 mg while the Ionophore used was Magnesium Ionophore III. The resulting Nernstian number is 26.9 mV/decade with a linear range of 0.1–10−6 M. Meanwhile, the resulting limit of detection (LoD) x[is]x was found to be 7.6 × 10−7 M. The Mg-ISE sensor also shows good selectivity with several ions, except with Ca2+-ion. In addition, the sensor can also work well for 9 weeks with an operating range at pH 4–9.