Improved Thiocyanate-Selective Electrode Based on Tetra(trimethylphenyl)-porphyrinato Manganese(III) Chloride: The Electronic and pH Effects

Bulletin of the Korean chemical society

Seungwon Jeon¹  Hyo Kyoung Lee¹  Hyung Ran Seo¹ 

关键词: Ion-selective electrodes;    Manganese porphyrins;    Potentiometric determination;    Polymeric membrane;    Thiocyanate ion;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

The thiocyanate-selective PVC membrane electrodes based on 5,10,15,20-tetrakis(2,4,6-trimethylphenyl)-porphyrinatomanganese(III) chloride [Mn(TMP)Cl] and 5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrinatomanganese(III) chloride [Mn(Cl8TPP)Cl] as ion carriers were investigated. The effect of ionophores, membrane compositions, plasticizers, and solution pHs on the response characteristics were studied. The Mn(TMP)Cl as an ionophore shows the best potentiometric sensitivity with a slope of -58.7 mV/decade and a detection limit of log[SCN?] = -6.90, and selectivity for thiocyanate over strong hydrophobic interfering anions such as ClO4 ? and salicylate. The potentiometric response is affected by the electronic effect of the substituents and solution pHs. The presence of substituents with electron donating and more liphophilic characters around the ligated metal center produces an improved response toward SCN?.

【 授权许可】

Unknown