Measuring Both pH and O2 with a Single On-Chip Sensor in Cultures of Human Pluripotent Stem Cell-Derived Cardiomyocytes to Track Induced Changes in Cellular Metabolism

In vitro studies which focus on cellular metabolism can benefit from time-resolved readouts from the living cells. pH and O-2 concentration are fundamental parameters upon which cellular metabolism is often inferred. This work demonstrates a novel use of a ruthenium oxide (RuOx) electrode for in vitro studies. The RuOx electrode was characterized to measure both pH and O-2 using two different modes. When operated potentiometrically, continuous pH reading can be obtained, and O-2 concentration can be measured chronoamperometrically. In this work, we demonstrate the use of the RuOx electrodes in inferring two different types of metabolism of human pluripotent stem cell-derived cardiomyocytes. We also show and discuss the interpretation of the measurements into meaningful extracellular acidification rates and oxygen consumption rates of the cells. Overall, we present the RuOx electrode as a versatile and powerful tool in in vitro cell metabolism studies, especially in comparative settings.

Automated summary

This study introduces a novel use of a ruthenium oxide electrode for in vitro cell metabolism studies, demonstrating its ability to infer different types of metabolism in human pluripotent stem cell-derived cardiomyocytes. The electrode can provide continuous pH readings and measure O-2 concentration over time, allowing for interpretations of extracellular acidification rates and oxygen consumption rates of the cells. The RuOx electrode is presented as a versatile and powerful tool for in vitro cell metabolism studies, particularly in comparative settings.