This work presents a low power microstrip transmission line PCR thermo-cycler based on microwave heating that is designed for low-budget, portable/Point of Care (POC) genetic analysis. Previous efforts on miniaturized PCR chambers focused mainly on resistively heated chambers employing DC heated micro-elements. However, these typically consume a significant amount of power with high voltage requirements and provide fixed heating profiles depending on the physical structure of the heater. Our system is composed of a transmission line with tuning stubs on a polycarbonate substrate tuned at 9.8GHz that couples microwave power from a signal source to a 4.0 L fluidic chamber. The performance of the system is tested employing water, which has the highest permittivity and loss tangent, facilitating coupling of electromagnetic waves. The temperature in the fluid can be controlled by adjusting the microwave input power. Experimental results showing the temperature increase as function of microwave power with a heating rate of 25.2 °C/second and a cooling rate of 9 °C/second at a maximum microwave power of 0.7Watts. Measured temperature is compared with prediction of lumped element modeling and finite element modeling using ABAQUS. Our measurements and simulations results prove the capability of microwave-based heating for PCR thermo-cycling.
Journal: TechConnect Briefs
Volume: 2, Nanotechnology 2008: Life Sciences, Medicine & Bio Materials – Technical Proceedings of the 2008 NSTI Nanotechnology Conference and Trade Show, Volume 2
Published: June 1, 2008
Pages: 577 - 580
Industry sectors: Medical & Biotech | Sensors, MEMS, Electronics
Topic: Chemical, Physical & Bio-Sensors