A Microelectrode‐Integrated Perfusable Vessel‐on‐a‐Chip Enabling Simultaneous Measurement of Transendothelial Electrical Resistance and Vascular Permeability

Transendothelial electrical resistance (TEER) is a well‐established method for evaluating tight junction integrity, providing real‐time, non‐invasive monitoring of barrier function. However, conventional TEER assays are largely restricted to 2D monolayer cultures and fail to capture the physiological complexity of 3D vascular structures. Here, we present a microfluidic platform that integrates gold‐patterned electrodes on a glass substrate with a polydimethylsiloxane (PDMS)‐based chip to enable simultaneous measurement of TEER and vascular permeability. Within this system, human endothelial cells undergo angiogenic self‐assembly to form perfusable, lumenized microvessels that are maintained under standard culture conditions. Real‐time impedance analysis using a precision LCR (Inductance, Capacitance, and Resistance) meter allows high‐resolution monitoring of barrier resistance, while parallel quantification of FITC‐dextran flux provides complementary permeability data. Impedance values obtained at optimized frequencies strongly correlate with paracellular tracer leakage, validating TEER as a robust functional readout in 3D vascular models. By coupling electrical and molecular assays in a physiologically relevant platform, our approach offers a scalable tool for real‐time evaluation of endothelial function with broad applications in drug screening, disease modeling, and vascular biology research.