Counter electrode based on an ion-exchanger Donnan exclusion membrane for bioelectroanalysis.

摘要: Ion-exchanger based Donnan exclusion membranes (IEDEM) are studied here as separators for counter and pseudo-reference electrodes in bioelectroanalysis. Since the potential across membrane remains indifferent a wide range of current densities contact with electrolyte solutions, IEDEM behave ideally non-polarizable membranes. Consequently, such may be suitable or reference electrode, depending on adopted cell configuration (three- two-electrode system). Four configurations were characterized order to establish limitations commercial anion-exchanging membranes, using chronopotentiometry readout protocol. Three- without exhibited similar characteristics terms drift reproducibility (observed RSD 0.0007 s1/2 per scan number 1.71%, respectively). Several currents amplitudes applied evaluate upper limits which was found at about 10 mA [42.8 cm−2]. This value is significantly above those typically used chronopotentiometric experiments, involve hundreds μA. Three different analytes measured human whole blood an electrode. A divalent cation (calcium), polyion (protamine), anion (chloride) successfully determined compared methods. Finally, obtained results suggest that bioelectrochemical sensing approaches replace expensive but less appropriate electrode materials measurement matrices contain lipids proteins.