Miniaturised ion-selective sensor chip for potassium measurement in a biomedical application


In critical care the blood potassium concentration is an important parameter to characterise the patient's condition. To switch from the common ex situ determination of potassium (mostly in serum) to the in vivo monitoring of K+ in whole blood opens new dimensions in diagnostics but produces a number of problems to be solved. For the task a new potassium sensitive microsensor assay with an integrated micro reference electrode was developed using silicon technology. In this paper we discuss the manufacture and performance of a potassium sensitive catheter-chip in respect to slope, reproducibility, reliability and long time stability in biological fluids.

Publication Title

Sensors and Actuators, B: Chemical