A porous hollow fiber sensor for detection of cellular hydrogen peroxide release based on cell-in-lumen configuration

•A porous hollow fiber structure was developed to monitor cellular H2O2 in-situ.•Porous structure enables higher enzyme stability and extended monitoring period.•Continuous monitoring provides more information on cellular metabolic dynamics. The rapid and accurate detection of cellular hydrogen peroxide (H2O2) is of great significance in cell monitoring and drug screening. We have developed a porous hollow fiber sensor with a cell-in-lumen configuration to detect H2O2 released by cells in real-time. In contrast to the conventional two-dimensional electrode structure, the sensing unit was located at the outer surface of the hollow fiber, while cells grew in the lumen, and the released H2O2 can diffuse through the porous wall of the fiber. The sensing layer wrapped outside the porous hollow fiber can capture the released H2O2 in a flow-through mode, resulting in a high sensitivity to the nanomolar level. In short-term monitoring of cell respiratory burst, the current response of the cell-in-lumen sensing configuration was six times greater than that of a conventional cell-out-electrode configuration. The porous wall also separated the cells and electrodes, minimizing the impact of electrical field on the cells. The high sensitivity and stability of detection ensured the cell-in-lumen configuration could be used to monitor the cellular H2O2 gradual release process induced by anticancer drugs. Such in-situ monitoring of the cellular release of H2O2 provides a new in-vitro drug screening platform for personalized medicine and cancer therapy.