MEASUREMENT OF CHANGES IN TISSUE METABOLISM USING A CLARK-TYPEOXYGEN SENSOR

摘要

This paper presents data characterizing the ability tomeasure metabolic activity at a tissue interface using a Clark-typeoxygen concentration sensor consisting of a microfabricated thinfilmelectrode matrix overlaid with a solid-state proton conductivematrix and encapsulated in a bio-inert polytetrafluoroethylenefilm. HL-1 atrial myocytes were cultured onto the sensor surface.Cyclic voltammetry was utilized to characterize the sensorresponse over 30 minutes while the overlying tissue was subjectedto either triiodothyronine or verapamil, drugs known to upregulateor downregulate, respectively, the metabolic activity ofmyocardial cells. Levels of percent of baseline current werecalculated for both drugs, as well as for controls. The change ofmeasured oxygen concentration was considered inverselyproportional to the change in metabolic activity. Each of the drugsexerted a significant metabolic effect on the tissue, as evidencedby changes in the sensor current, thus confirming the ability tomeasure cellular metabolic changes at the tissue surface using theClark-type oxygen sensor. Verapamil at 25μg/L was found toincrease oxygen concentration to 135±4% as compared to controlvalues (95±8%). Triiodothyronine at 2.5μg/L, on the other hand,decreased oxygen levels in the extracellular space to 85±9%, ascompared to baseline oxygen (98±6%). The recorded metaboliceffects of the tested drugs were consistent with their knownphysiologic effects. This sensor has possible applications in drugscreening or toxicological detection.