Transducer Systems Integrated into Organ-on-a-Chip Devices: From Detection to Fabrication

Organ-on-a-chip (OoC) devices are an emerging class of advanced microfluidic systems that replicate human physiological functions at the microscale. Enabled by advances in microfabrication techniques (cleanroom-based microfabrication and 3D printing technologies) and tissue engineering, OoCs allow culture cells, manage fluid flow, and recreate biochemical and mechanical stimuli, with high reproducibility and low cost. Therefore, they offer a promising alternative to the traditional preclinical testing of pharmaceutical drugs, contributing to predict the efficacy of new developed drugs. Nevertheless, for this prediction is essential an accurate monitoring of cellular responses over time. However, the effective integration of various types of transducers-optical, electrochemical, mechanical, and resistive-into a single platform for real time monitoring remains a key challenge. This review explores the main transduction techniques used in OoCs, as well as current strategies, limitations, and suggests potential solutions for their integration into functional organ models.