Flow‐Injection Amperometric Detection with Solvent Polymeric Membrane Ion Sensors

Abstract

An amperometric detector for hydrophobic ions based on a plasticized poly(vinyl) chloride (PVC) membrane incorporated in a flow-injection system was developed. A four-electrode potentiostat with ohmic drop compensation was used, while a flow-through cell incorporated the four electrodes and the membrane, which contained tetrabutylammonium tetraphenylborate. When the influence of the applied potential and of the flow-injection variables on the determination of tetrabutylammonium was studied, a linear relationship was observed between current peak height and ion concentration over a range of 5 Â 10 À6 ± 6 Â 10 À5 M tetrabutylammonium. Good repeatability and between-day reproducibility and high sample frequency were obtained. The effect of other ions was studied. Two different amperometric methods, indirect and direct, were also developed for the determination of dodecylsulfate in the concentration range 3 Â 10 À5 ± 9 Â 10 À4 M.

Flow-injection amperometry at microfabricated silicon-based μ-liquid–liquid interface arrays

“…On the whole, this problem was circumvented by gellification of the organic phase with poly(vinyl) chloride (PVC) [12,14,18,20,24,[28][29][30][31][32][33] or insertion of solid porous membrane materials between the two immiscible solutions [13, 15-17, 21, 23, 25-27]. Inevitable reductions in diffusion coefficients of the analyte ions, associated with gellification of the organic phase, have not proven problematic when monitoring ion transfer by amperometric and voltammetric methods.…”

State-of-the-Art of (Bio)Chemical Sensor Developments in Analytical Spanish Groups

“…The flow-through cell incorporated the four electrodes and the membrane, which contained tetrabutylammonium tetraphenylborate. The determination of tetrabutylammonium was studied and two different amperometric methods, indirect and direct, were also developed for the determination of dodecylsulfate [ 212 ], tracine [ 213 ], tiapride [ 214 ], sulpiride [ 215 ] and catamphiphilic drugs such as the antiarrhythmic drugs procainamide and quinidine, the antimalarial quinine and the anesthetics bupivacaine, lidocaine, procaine and tetracaine [ 216 ]. Finally, a solvent polymeric membrane ion sensor has been applied to study the ion transfer of several ionic liquid cations, from water to a poly(vinyl chloride) membrane plasticized with 2-nitrophenyl octyl ether and the study has mainly been focused on dialkylimidazolium and alkylpyridinium cations [ 217 ].…”

Assessment of ion transfer amperometry at liquid–liquid interfaces for detection in CE

“…Electrochemistry at the interface between two immiscible electrolyte solutions (ITIES) [14,15] has been used to detect non-redoxactive species by voltammetry or amperometry [16][17][18]. In this case, an electrical potential is applied across the interface between two immiscible solutions containing electrolytes.…”

“…Initial research involved the use of flow injection analysis systems using electrochemistry at the ITIES as the method of detection. A flow cell was constructed containing a stationary organic phase, over which the aqueous phase containing the plug of analyte flowed [16,22,[24][25][26][27][28][29]. The ITIES may also be employed for detection in ion chromatography [28].…”