Membrane Composition Effects on the Analytical Behavior of Solid Contact Potentiometric Pb2+ Selective Electrodes Based on Diazadibenzo-18-crown-6 Ionophores
Por:
Ochoa G.C., Aguilar-Cordero J.C.
Publicada:
1 jul 2011
Resumen:
The effect of component contents and membrane thickness on the detection limit (DL), slope (m), linear range (LR) and response time (RT) of Pb2+ solid contact potentiometric ion selective electrodes (SCISE) based on 4,10diaza- 2,3,11,12-dibenzo-18-crown-6 (1), 4,10-diaza-2,3,11,12-di(4-tert-butylbenzo)-18-crown-6 (2) and 4,10-diaza2,3,11,12- dibenzo-18-crown-6-N, N'-di(carboxymethyl) (3) as ionophores was studied by open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) measurements. The use of an intermediate layer of poly(3-octyl) thiophene between the gold substrate and the selective membrane was explored. SCISE prepared showing the best responses had typical DL, m, LR and RT values of 10(-6) M, 29 mV/dec, 10(-5) to 10(-3) M and 2 minutes.
Filiaciones:
Ochoa G.C.:
Univ Nacl Autonoma Mexico, Fac Quim, Dept Quim Analit, Mexico City 04510, DF, Mexico
Aguilar-Cordero J.C.:
Univ Nacl Autonoma Mexico, Fac Quim, Dept Quim Analit, Mexico City 04510, DF, Mexico
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