Fabrication and characterization of a PDMS–glass hybrid continuous-flow PCR chip

A continuous-flow (CF) microchip was fabricated using polydimethylsiloxane (PDMS)/glass laminate for efficient polymerase chain reaction (PCR). The temperatures of the three separate zones, corresponding to the three PCR thermal cycling steps were controlled using an external PID temperature controller. A PCR mixture was introduced to the CF microchip using a syringe pump. The hydrophobic surface of the PDMS channel which adsorbs enzymes was modified by adding 2.5% polyvinylpyrrolidone (PVP) to the PCR mixture. The effect of flow rate in the CF chip on DNA amplification was examined and its PCR efficiency was compared with that of conventional PCR. The microchip requires only 8–30 min to produce detectable amounts of PCR products as determined by slab gel separation, whereas a conventional thermocycler requires 90–150 min over 30 amplification cycles to achieve the same result.