Surface modification-assisted bonding of polymer-based microfluidic devices

This paper reports on the development and application of a surface modification technique as an improved method for bonding polymer microfluidic substrates. This technique readily produced complete microfluidic chips via plasma oxidation followed by silane reagent treatment on the polymer surface. Characterization of the bonded chips was performed using scanning electron microscopy (SEM), water contact angle measurement, and tensile strength measurement. SEM images showed that the integrity of the channel features was successfully preserved. A bond strength approaching that of solvent welding was demonstrated. This technique has been successfully applied to bond dissimilar polymer substrates (polymethylmethacrylate (PMMA), amorphous polyethylene terephthalate (APET), polycarbonate (PC)), and is also applicable to bonding a hard polymer substrate to polydimethylsiloxane (PDMS) or glass.