Development of a Fluoride-Selective Electrode based on Scandium(III) Octaethylporphyrin in a Plasticized Polymeric Membrane

• Published in: Bulletin of the Korean Chemical Society 2010, Vol.31 (6), p.1601-1608
• Main Authors: Kang, Young-Jea, Lutz, Christopher, Hong, Sung-A, Sung, Da-Yeon, Lee, Jae-Seon, Shin, Jae-Ho, Nam, Hak-Hyun, Cha, Geun-Sig, Meyerhoff, Mark E
• Format: Article
• Language: Korean
• ISSN: 0253-2964; 1229-5949

A scandium(III) porphyrin-based fluoride-selective potentiometric sensor and its application in the analysis of hydrofluoric acid is described. Scandium(III) octaethylporphyrin, an ionophore recently developed for the optical fluoride sensor, was employed as a host molecule for the selective binding with fluoride in the plasticized PVC membrane. Nernstian response for $F^-$ between $10^{-4.6}$ to $10^{-1}$ M was observed at a glycine-phosphate buffer (pH 3.0). The selectivity pattern was observed as $F^-$, salicylate $\gg$ $SCN^-$ > $Cl^-$, $Br^-$, $NO_3{^-}$, $ClO_4{^-}$, which is consistent with the binding constant data measured in the plasticized PVC membrane based on a sandwich membrane method. This highly selective and reversible fluoride-sensitive electrode was employed for the analysis of hydrofluoric acid (HF). A disposable differential-type HF sensor was fabricated on the screen-printed electrode and demonstrated its ability to detect the neutral HF in the acidic solution.