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 for Be 2+ ions over a wide concentration range (4.0 × 10 - 3 −2.5 × 10 - 6 M) with a limit of detection of 1.0 × 10 - 6 M (9.0 × 10 - 3 ppm). It has a response time of ∼50 s and can be used for at least 4 months without any divergence in potential. The proposed electrode revealed very good selectivities for Be 2+ 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 beryllium in a mineral sample.