A comparative study on fabrication of Mn~(2+) selective polymeric membrane electrode and coated graphite electrode

摘要

Poly(vinyl chloride)-based membranes of two ligands 2,4-bis(2-acetoxybenzylamino)-6-phenyl-1,3,5-triazine (L_1 and N2,N4-di(cyanoethyl)-2,4-bis(2-acetoxybenzylamino)-6-phenyl-l,3,5-triazine (L_2) were fabricated and ex plored as Mn~(2+) ion selective electrodes. The performance of the polymeric membranes electrodes of ionophore with different plasticizers (dibutylphthalate, benzoic acid, o-nitrophenyloctyl ether, 1-chloronapthalene andtri-n butylphosphate) and anion excluders (sodium tetraphenylborate and potassium tetrakis p-(chloro phenyl)borate was looked in to and the better results were obtained with the membrane having composition L_2: NaTPB: DBP: PV( as 6: 3: 56: 35 (w/w; mg). The coated graphite electrode (CGE) with same composition was also fabricated am investigated as Mn~(2+) selective electrode. It was found that CCE showed better response characteristics than PME The potentiometric response of CGE was independent of pH in the range 3.0-9.0 exhibiting the Nernstian slopi 29.5 ±0.3 mV decade~（-1） of activity and working concentration range 4.1×10~（-7）-1.0× 10~（-1） mol L~(-1) with a limi of detection 6.7 × 10~(-8) mol L~(-1). The electrode showed a fast response time of 12 s with a shelf life of 105 days The proposed CGE could be successfully used for the determination of Mn~(2+) ions in different water, soil, vegetable: and medicinal plants also used as an indicator electrode in potentiometric titration with EDTA.