Figure 1.

(Aa) Schematic diagram showing the setup for simultaneous measurement of oxygen consumption and generation of hydrogen peroxide (H₂O₂) using an electrochemical method. Carbon microelectrode for detection of oxygen reduction current and Os-HPR modified carbon microelectrode for detection of reduction current for H₂O₂. (Ab) Real-time monitoring of oxygen consumption and H₂O₂ production during respiratory burst in THP-1 cells with exogenous addition of 20 nM PMA. (Ba) Schematic representation of the setup for evaluation of two-dimensional (XY-scan) and quantitative respiration (Z-scan) activity in THP-1 cell chip using SECM (insert shows the photograph of the cell-chip used). (Bb) Diagram showing the dimensions of the cell chip prepared for XY-scan (I) and Z-scan (II).