Fabrication of hybrid-nanofluidic with hydrophilic polymer for DNA separation capillary electrophoresis module Original Research Article

We developed novel hydrophilic polymer (HP) with excellent processability and UV/thermal curability, which reveled low contact angle range at 13–23°, depending on the chemical composition. This patented HP was synthesized by homogeneously mixing the silica–titania complex with Tiron, (HO)2C6H2(SO3Na)2 and organic coupling additives of diacrylate oligomer. Moreover, it is advantageous that the cured HP exhibited high resistance to several organic solvents and UV/visible transparency and high replication fidelity. To fabricate hybrid HP microfluidic device, HP layer was reinforced by polydimethylsiloxane (PDMS) as a support matrix. The leak-free channel structures were built with strong bond to glass surface by plasma treatment, and the flow behavior was comparatively observed with that of the conventional PDMS channel structures. Aqueous solution could spontaneously flow only by capillary force through the fabricated HP micro and nanochannels while no flow into PDMS channels having same dimensions, due to the hydrophobic non-wetting nature. Moreover, PDMS did not exactly replicate the nanoscale pattern of Si master, but HP revealed excellent replication fidelity. And the HP exhibited additional advantages such as high optical transparency in visible and ultraviolet region. This novel HP must be promising as a matrix material of aqueous-based micro/nanofluidic devices such as biosensors, capillary electrophoresis module and microbioreactors by soft lithography techniques.