: Meyer, H.; Drewer, H.; Krause, J.; Cammann, K.; Kakerow, R.; Manoli, Y.; Mokwa, W.; Rospert, M.

Abstract
A monolithic sensor chip containing a sensor array of 400 individually addressable platinum microelectrodes has been fabricated. This sensor array can be used in potentiometric mode as well as in amperometric mode for redundant measurements with signal averaging, multi-analyte measurements and imaging of analyte distributions. The sensor array is coated with an ammonium-selective PVC membrane for creating a chemical sensor array and, additionally, with a urease membrane for creating a biosensor array. Thus, two-dimensional imaging of the distributions of ammonium and urea can be obtained.