Bent polydimethylsiloxane–polycarbonate hybrid microdevice for on-chip flow-through polymerase chain reaction employing a single heater

We report on a bent microdevice made from elastomeric polydimethylsiloxane (PDMS) on a polycarbonate (PC) solid support. Its bent shape is well sustained, and this allows an on-chip flow-through polymerase chain reaction (PCR) to be performed employing a single heater. The PC support was bent to a predetermined angle by heating the substrate close to the glass transition temperature of PC, and the PDMS microdevice was physically adapted to the curvature of the bent PC. The relatively short plane of the bent PC substrate was then placed on top of a heater, leaving the relatively long plane floating in the air, on the entire surface of which a temperature gradient was established. The plane in contact with the heater represents the zone for denaturation, and the slanted plane floating in the air acts as the annealing/extension zone. Two targets with amplicon sizes of 230 and 282 bp were successfully amplified utilizing microdevices with 4° and 17° inclination angles, respectively, by employing a single heater in both cases and within 30 min. The system provides an effective alternative to conventional 3-temperature control flow-through PCR devices by minimizing the accessories and hence facilitating system miniaturization.