Paula C R Corsato, Christian O Silva, Yasmin Watanabe, Juliana N Y Costa, Gabriel J C Pimentel, Rodrigo S Costa, Lucian F Bellini, Bruna G Olsen, Flávio M Shimizu, Rui C Murer, Maria H O Piazzetta, Angelo L Gobbi, Gabriel R Schleder, Iris R S Ribeiro, Renato S Lima
Standard and recently developed methods face downsides to provide convenient, high-throughput susceptibility testing of adherent cells, delaying the assessment of drug candidates over preclinical trials. Here, we report advances that render a reversible millifluidic electrochemical arrayed device a low-cost, scalable, stable, and reusable platform toward susceptibility testing across user-friendly, reproducible, and fast analyses. Multisensor devices integrating Ti/Ni/Ag thin films-based quasi-reference electrodes, highly cross-linked SU-8, and optimized fluidic dimensions can successfully deliver long-term cellular analyses. On-chip sensors are reversibly bonded to PDMS, which allows us to regenerate electrodes. When it comes to the analysis routine, the PDMS design (with outlets at its bottom) yields power-free pumping, automatic pipette-aided fluidic tests, whereas an Android app-controlled handheld equipment enables wirelessly programming sensor use. Moreover, a single machine learning descriptor can accurately predict the viability of two tumor cells, i.e., MDA-MB-231 (breast) and HT-29 (colorectal cancer) cells, in response to doxorubicin. This is a preliminary but encouraging indicator toward calibration-free sensor adoption. While the prior advances enhance the approach's applicability cooperatively, the throughput is augmented through serial, fast (3 s) analyses of on-chip 45 sensors. The addressed foundation may play an essential role in steering the platform for daily practice-deployable, high-throughput drug susceptibility testing.