The principal objective of the integrated circuit chemical sensitive field effect transducer program (NIGMS Grant #1 RO1 GM22952) is to develop several types of biomedical sensors based on integrated circuit and electrode technology. Primary program goals include the development of sensors to detect ions and reducible gases; secondary goals include sensors based on enzymatic and immunochemical reactions. These goals include the development of a series of multi-sensor IC chips with the appropriate on-chip electronic signal processing capability. The overall program goals include evaluation testing of the various microelectronic biomedical sensors to determine important characteristics such as concentration ranges, selectivity constants, sensitivities, long-term stability and short-term drifts, precision and accuracy. The prototype devices are to be evaluated first in aqueous solutions, animal blood or serum, and then in continuous animal monitoring situations. Finally, the devices are to be evaluated in human blood or serum to determine the protein interferences or interactions and such other effects as clotting and toxicity.