Thermal cycling characteristics of a 3D-printed serpentine microchannel for DNA amplification by polymerase chain reaction

A polymerase chain reaction (PCR) device with integrated heaters for DNA amplification is proposed by using 3D-printing technology, which has the advantages of fast prototyping, design flexibility, and low cost. The thermal characteristics of the 3D-printed device for PCR are reported for the first time. The overall dimensions of the PCR device are 30 mm × 40 mm where a serpentine microchannel is created to implement 27 thermal cycles. The serpentine microchannel of 260 μm in depth, 450 μm in width and 1470 mm in length has been designed to inspect shape conformity and temperature variations. Thermal cycling experiments has showed that three temperature zones for denaturation (90-95 °C), annealing (55-65 °C) and extension (70-77 °C) were successfully produced for DNA amplification. The thermal cycling efficiency ranges 67.4% to 47.8% when the flow rate is changed from 5 μL/min to 10 μL/min. The study demonstrates the feasibility of a low-cost 3D-printed PCR device that enables DNA amplification by thermal cycling. This paper concludes that 3D-printing technology can be applied for bio-microfluidic devices that require precise temperature control.