Method of using microfluidic chip for nucleic acid hybridization

A method of using a microfluidic chip for nucleic acid hybridization, comprising providing the microfluidic chip having a hybridization region installed with a porous substrate, an interstice being defined between the porous substrate and a sidewall of the hybridization region and surrounding the periphery of the porous substrate, the hybridization region being connected to at least one inlet and at least one outlet, respectively;

• the method includes the following steps:
• (a) mixing a test nucleic acid without a heat treatment and a marker-labeled nucleic acid probe to form a mixed solution, injecting the mixed solution into the microfluidic chip via the at least one inlet to fill the interstice between the porous substrate and the sidewall of the hybridization region for maintaining the test nucleic acid that hybridized to the marker-labeled nucleic acid probe being absorbed to the periphery of the porous substrate;
• (b) continuously injecting of an anionic surfactant, wherein the anionic surfactant is sodium dodecyl sulfate having a concentration ranged from 0.1% to 0.3% (w/v) or sarcosine having a concentration ranged from 0.3% to 0.4% (w/v), the anionic surfactant entering the interstice surrounding the periphery of the porous substrate via the at least one inlet and then flowing through the porous substrate from the periphery of the porous substrate toward the center of the porous substrate, the anionic surfactant being finally discharged via the at least one outlet;
• wherein injecting a buffer solution into the microfluidic chip prior to step (a) to activate the porous substrate with positive charges, to allow the test nucleic acid hybridized with the marker-labeled nucleic acid probe to form a micelle during washing with the anionic surfactant in step (b);
• and
• (c) detecting where there is specific hybridization of the test nucleic acid with the marker-labeled nucleic acid probe on the porous substrate after washing with the anionic surfactant within 400 seconds based on a movement of the test nucleic acid hybridized with the marker-labeled nucleic acid probe from the periphery of the porous substrate to the center of the porous substrate.