A novel thiocyanate-selective electrode based on a zinc-phthalocyanine complex

作者：Xu WJ; Chai YQ; Yuan R^*; Liu SL

来源：Analytical and Bioanalytical Chemistry, 2006, 385(5): 926-930.

DOI：10.1007/s00216-006-0512-4

• zinc-phthalocyanine complex
• neutral carrier
• thiocyanate
• ion-selective electrode

A novel thiocyanate (SCN-)-selective PVC membrane electrode based on a zinc-phthalocyanine ( ZnPc) complex as neutral carrier is described. The membrane electrode containing ZnPc with 5.1% (w/w) ionophore, 29.2% (w/w) PVC, and 65.7% (w/w) 2-nitrophenyl octyl ether (o-NPOE) as plasticizer displayed an anti-Hofmeister selectivity sequence (SCN- > Sal(-) > I- > ClO4- > Br- > Cl- > NO3- > NO2- > H2PO4- > SO42- ), and exhibited near-Nernstian potential response to thiocyanate ranging from about 1.0 x 10(-1) to 1.0 x 10(-6) mol L-1 with a detection limit of 7.5 x 10(-7) mol L-1 and a slope of 58.1 +/- 0.5 mV per decade in pH 3.0 phosphate buffer solution at 25 degrees C. This preferential response is believed to be associated with the unique coordination between the central metal of the carrier and thiocyanate.

• 出版日期2006-7
• 单位西南大学