MINIMIZATION OF THE ACETATE INTERFERENCE OF CALCIUM-SELECTIVE CARRIER-PVC-MEMBRANE ELECTRODES FOR PROCESS-CONTROLLED HEMODIALYSIS

Up to now calcium-selective electrodes with carrier-PVC-membranes have shown a need for correction during their application in controlling t he process at an artificial kidney, for the presence of acetate anions leads to immense differences of measurements because of the anion int erference. On the basis of experimental research the membrane characte ristics could be changed in such a way that there is no need to correc t the measurements when the electrodes are used during bicarbonate hae modialyses with 2 mmol/l acetate. This was achieved by optimizing the ratio of the concentration of synthetic, electrically neutral carrier and lipophilic anion and by using plasticizer effects. A special membr ane was developed in the same way for an application in dialysis solut ions with 35 mmol/l acetate.