Ion-selective electrodes with improved detection limit for analysis in biological fluids.

Abstract:
The purpose of the proposed research is to extend the application of ion-selective electrodes (ISE) with improved detection limit for a determination of clinically relevant ions (Na+, K+, NH4+, Mg2+, Ca2+) in diluted blood plasma and urine samples. This approach should decrease the cost of clinical tests, and increase the lifetime of the sensing membranes by preventing their biofouling. Following issues will be addressed: (1) potentiometry of ISE with eliminating effects of zero-current ion fluxes, (2) ion amperometry of the polymeric ion-selective membranes, (3) impedance spectroscopy and computer simulation of ion concentration profiles in the membrane, (4) use of ISEs for a determination of inorganic ions in biological fluids. We expect that the results of this study will allow us to clarify the origin of the ISE potential, to assess the efficiency of various procedures leading to a lowering of the detection limit, and to develop a novel methodology for biomedical applications.