A novel capillary polymerase chain reaction machine

Abstract

I built a novel prototype capillary polymerase chain reaction machine. The purpose was to perform a single reaction as fast as possible with a reaction volume - 100 nl. The PCR mix is in the form of a 1 /1 droplet that moves between three heat zones inside of a 1 mm I.D. capillary filled with mineral oil via pneumatic actuation. A laser beam waveguides down the capillary until it strikes the drop, at which point it scatters. The scatter is picked up by a series of photodiodes to provide position feedback. Due to the efficient heat transfer arrangement, the drop can transition between different temperature steps in -2 seconds, which includes both drop motion and temperature equilibration. It was extensively tested in both 10-cycle and 30-cycle PCR, including nearly 200 successful 30-cycle runs. The 30-cycle PCR was typically 74% (as high as 78%) efficient, and took only 23 minutes. This compares well with existing machines in the literature.