Stereolithographic Hydrogel Microfluidic Platform for Monitoring Cellular Respiration via Scanning Electrochemical Microscopy

Hydrogel microfluidic devices have garnered significant interest as cell culture platforms owing to the efficient diffusion of nutrients through the hydrogel. Stereolithography, a versatile fabrication technique, has been widely adopted for the rapid prototyping of various microfluidic devices. Although evaluating cellular activity within microchannels during in vitro assays is essential, integrating electrochemical sensors into hydrogel devices remains challenging as these materials often cannot withstand conventional electrode fabrication processes. To address this limitation, scanning electrochemical microscopy was employed to assess cellular activity within hydrogel microfluidic devices, thereby eliminating the requirement for internal electrode fabrication. Initially, a novel hydrogel microfluidic design was developed, featuring accessible regions and thin hydrogel films. As a proof of concept, the respiratory activity of MCF-7 cells within a hydrogel microchannel was measured. This strategy is expected to facilitate future cell-based drug-screening applications.