Fabrication of Polymeric Membrane Electrodes Based Neutral Carriers for Potentiometric Determination of Mercury (II) Ions in water and real samples

The potentiometric response characteristics of mercury ion-selective membrane electrodes based on 2,2ʹ-Bis(N,N-diphenylamino)-4,4ʹ-diphenyl-5,5ʹ-bithiazole (L1) and 1,2-bis(quinolin-8-ylsulfanylmethyl)benzene(L2) were described. Ion selectivities were tested for various plasticizers, which were used as solvent mediatorsto incorporate the ionophores into the membrane. Effects of experimental parameters such as membranecomposition, nature and amount of plasticizers and pH on the potential response of Hg2+ electrodes wereinvestigated. The best performance was obtained with the electrode having a membrane composition (w/w) of(L1) (5.0%): PVC (31.0%): DOP (dioctylpthalate) (63.0%): NaTPB (sodium tetraphenylborate) (1.0%). Theproposed electrode reveals a Nernstian response over Hg2+ ion in the concentration range of 8.0×10−7–1.0×10−2M with limit of detection 4.1×10−7 M. The electrode shows good discrimination toward Hg2+ ion with respect tomost common cations. It shows a short response time (10 s). For evaluation of the analytical applicability, theelectrode was used in the determination of Hg2+ ion in real samples

کلیدواژه ها:

Ion-selective electrode ، Neutral ionophore ، Mercury(II) ، Plasticizer