Irreversible PDMS bonding using flame activation of adhesives for fabrication of microfluidic and organ-on-chip devices

[Display omitted] •PDMS bonding via flame-treated adhesives can withstand up to 325 kPa burst pressure.•This bonding technique is suitable for microfluidic and organ-on-chip fabrication.•Bonding strength was maintained after 3 weeks of cell culture.•Calu-3 epithelial cells developed functional tight-junction barriers on-chip.•Human lung fibroblast cells formed actin filament cytoskeleton networks on-chip. Polydimethylsiloxane (PDMS) is widely used for microfluidics fabrication in many disciplines due to its ease of use in soft lithography and its ability to bond liquid-tight seals. A variety of PDMS-PDMS bonding methods exist, but each may have limitations for some applications. For example, chemical bonding via oxygen plasma treatment is reliable but requires expensive equipment and specialized training. Here we present a rapid, low-cost, and accessible method for irreversible PDMS bonding in which flame treatment activates PDMS and Nitto 5302A adhesive surfaces. Using this technique, PDMS microchannels can be fabricated with a bonding integrity of up to 325 kPa burst pressure. This technique is suitable for fabricating organ-on-chip devices that support cell viability and establishment of key cellular features in cell line and primary cell cultures while maintaining bonding integrity.