3D-Printed\nDual-Channel Flow-Through Miniaturized\nDevices with Dual In-Channel Electrochemical Detection

Here, we present three-dimensional-printed dual-channel\nflow-through\nminiaturized devices (3D<sub>d</sub>) with dual electrochemical detection\n(ED<sub>d</sub>) integrating two working electrodes each in an in-channel\nconfiguration (3D<sub>d</sub>-ED<sub>d</sub>). Prussian Blue (PB)\nshell-gold nanoparticles ((PB)AuNP) core-based electrochemistry was\nchosen for selective hydrogen peroxide determination. 3D<sub>d</sub>-ED<sub>d</sub> devices exhibited impress stability, identical intrachannel\nand interchannel electrochemical performances, and excellent interdevice\nprecision with values under 9%, revealing the reliability of the design\nand fabrication of the devices. 3D<sub>d</sub>-ED<sub>d</sub> enabled\nlong-term reliable hydrogen peroxide determination at physiological\npH in Caco-2 cells under prooxidant stimulation demonstrating its\noutstanding electroanalytical performance. The results highlight the\nanalytical versatility and trustworthiness of 3D-printing-based devices\nat miniaturized scale integrating advanced electrochemistry and its\npotential for real-time cell monitoring.