Beryllium-selective membrane electrode based on benzo-9-crown-3

A PVC membrane electrode for beryllium(II) ions based on benzo-9-crown-3 as membrane carrier was prepared. The sensor exhibits a Nernstian response fo r Be2+ ions over a wide concentration range (4.0 x 10(-3)-2.5 x 10(-6) M) w ith a limit of detection of 1.0 x 10(-6) M (9.0 x 10(-3) ppm). It has a res ponse time of similar to 50 s and can be used for at least 4 months without any divergence in potential. The proposed electrode revealed very good sel ectivities for Be2+ over a wide variety of other cations including alkali, alkaline earth, transition, and heavy metal ions and could be used in a pH range of 2.0-6.0. It was successfully applied to the determination of beryl lium in a mineral sample.