A new ytterbium(III) PVC membrane electrode based on 6-methy-4-{[l-(lH-pyrrol-2-yl)methylidene]amino}-3-thioxo-3,4dihydro-1,2,4-triazin-5(2H)-one

摘要

This study presents the development of an original electrode,employing 6-methy-4-{[l-(lH-pyrrol-2-yl)methylidene]amino}-3-thioxo-3,4dihydro-l,2,4-triazin-5(2H)-one (PMTO) as a suitable ionophore.Interestingly,the electrode performance provided a very good response for Yb3+in a wide concentration range (from 1.0 x 10~(-6) to 1.0 x 10~(-1) mol L~(-1)) with a detection limit of 4.6 x 10~(-7) mol L~(-1) and a slope of 19.5+-0.3 mV per decade of Yb3+concentration.Furthermore,it possessed a fast response time of about 10 s and it functioned in the pH range of 3.3-8.0 with a usage of at least 2 months without observing any deviations.Noticeably,the proposed electrode revealed an excellent selectivity for Yb3+over a broad variety of alkali,alkaline earth,transition and heavy metal ions.The practical applicability of the electrode was demonstrated by its utilization as an indicator electrode in the potentiometric titration of Yb3+ions with EDTA and in the determination of F~-in mouth wash samples.Additionally,it was also applied for the determination of Yb3+ions in binary mixtures.