New elongated series of thermoelectric coolers improves temperature precision control in PCR devices
Thermal Cycling devices used for Real-Time PCR utilize thermoelectric technology to precisely manage temperature set points and ramp rates, enabling amplification of DNA segments. To improve temperature precision control in PCR devices, Laird Thermal Systems has developed an elongated series of PowerCycling PCX thermoelectric coolers. Utilizing proprietary processes and a unique module construction, the PCX Elongated Series provides high reliability and a minimal temperature gradient for PCR applications resulting in greater throughput and faster test results.
PCR requires a high number of thermal cycles to create millions of DNA strands used for medical diagnosis. Each thermal cycle consists of three steps, where the first separates the DNA strands at a high temperature of 95°C. The second step is a cool down to a melt temperature between 50 to 65°C where the biomarkers will bond to the DNA and the third stage increases the temperature to 72°C to sequence a copy of the DNA. Thermoelectric coolers are installed under the PCR wells to precisely manage these temperature setpoints to within ±0.5ºC.
Determining the optimum melt temperature of each thermal cycling stage is often a time-consuming process for laboratory technicians. By creating more temperature zones on the PCR tray, the optimal melt temp can be found. The new PCX Elongated series allows for more narrow temperature zones than standard thermoelectric coolers, providing more precise temperature control across the tray, making it easier for technicians to determine the right temperature.
“Elongated thermoelectric coolers are extremely challenging to manufacture due to the bowing effect that can occur with longer parts. The longer the length is to the width, the more likely the ceramics tend to bow, which can be challenging to manufacture”, said Andrew Dereka, Product Director at Laird Thermal Systems. “Through proprietary process controls and advanced semiconductor materials, our PCX Elongated thermoelectric cooler eliminates the impact of this effect to provide a highly reliable part for Real-Time PCR.”
The PowerCycling PCX Series features a unique robust construction with a thermally conductive “soft layer” that absorbs the mechanically induced stresses caused by thermal cycling applications. This series has been tested to meet the latest PCR industry standards without degrading in performance.