sn (ii) ion- selective membrane electrode based on dibenzo-18-crown-6

we found that dibenzo-18-crown-6 (db18c6) can be used as an ionophore to make a tin (ii)-ionselectivemembrane electrode. the electrode exhibits a near nernstian response for sn2+ ions over aconcentration range from 1.0× 10-6 – 1.0× 10-2 m with a slope of 27.5 ± 0.6 mv per concentration decadein an acidic solution (ph=1). the limit of detection was 8.0× 10-7 m. it has a response time of < 20s andcan be used for at least 3 months without any divergence in potentials. the proposed membrane electroderevealed very good selectivity for sn2+ ions over a wide variety of other cations and could be used inacidic media. it was used as indicator electrode in potentiometric determination of tin (ii) ion in realsample.