Tunable and Reversible Gelatin-Based Bonding for Microfluidic Cell Culture

The development of novel bonding techniques could enable new applications and uses of plastics in microfluidic cell culture, complementing the omnipresent polydimethylsiloxane (PDMS). In this respect, the present paper describes a reversible gelatin-based method (named GEL-D) for bonding microfluidic chip parts, constituted of different materials. The herein introduced method enables the bonding of the most of the commonly used materials in microfluidics such as PMMA, PDMS, glass and NOA. Notably, the fabricated chips resist to pressure up to 0.7 MPa, to organic solvent exposure and temperature up to 70 °C. To show the versatility of the described method, microchips with different sizes, materials, and geometries were bonded, including microchannel down to 200 µm (width x depth) and round microstructures. The bonded chips are suitable to microfluidic cell culture procedures, including formation of microtissues, cells viability analysis and confocal microscopy. Therefore, the room-temperature bonding method appear to be highly efficient for cell culture on plastic chips, where in situ analysis of the seeded cells is required after microchip de-bonding.