一种基于锌酞菁配合物的新型硫氰酸盐选择性电极。

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

作者信息

Xu Wen-Ju, Chai Ya-Qin, Yuan Ruo, Liu Su-Li

机构信息

Chongqing Key Laboratory of Analytical Chemistry, e College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, People's Republic of China.

出版信息

Anal Bioanal Chem. 2006 Jul;385(5):926-30. doi: 10.1007/s00216-006-0512-4. Epub 2006 May 24.

DOI:10.1007/s00216-006-0512-4

PMID:16791573

Abstract

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- > SO4(2-)), 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.

摘要

描述了一种基于锌酞菁（ZnPc）配合物作为中性载体的新型硫氰酸盐（SCN-）选择性PVC膜电极。该膜电极含有5.1%（w/w）离子载体的ZnPc、29.2%（w/w）PVC和65.7%（w/w）作为增塑剂的2-硝基苯基辛基醚（o-NPOE），呈现出反霍夫迈斯特选择性顺序，即SCN- > Sal- > I- > ClO4- > Br- > Cl- > NO3- > NO2- > H2PO4- > SO4(2-)，并且在25℃下pH 3.0的磷酸盐缓冲溶液中，对硫氰酸盐的电位响应接近能斯特响应，范围约为1.0×10(-1)至1.0×10(-6) mol L(-1)，检测限为7.5×10(-7) mol L(-1)，斜率为每十倍变化58.1±0.5 mV。这种优先响应被认为与载体中心金属与硫氰酸盐之间独特的配位作用有关。