Mondal Sudip, Venkataraman V
Department of Physics, Indian Institute of Science, Bangalore-560012, India.
J Biochem Biophys Methods. 2007 Aug 1;70(5):773-7. doi: 10.1016/j.jbbm.2007.05.001. Epub 2007 May 8.
DNA amplification using Polymerase Chain Reaction (PCR) in a small volume is used in Lab-on-a-chip systems involving DNA manipulation. For few microliters of volume of liquid, it becomes difficult to measure and monitor the thermal profile accurately and reproducibly, which is an essential requirement for successful amplification. Conventional temperature sensors are either not biocompatible or too large and hence positioned away from the liquid leading to calibration errors. In this work we present a fluorescence based detection technique that is completely biocompatible and measures directly the liquid temperature. PCR is demonstrated in a 3 muL silicon-glass microfabricated device using non-contact induction heating whose temperature is controlled using fluorescence feedback from SYBR green I dye molecules intercalated within sensor DNA. The performance is compared with temperature feedback using a thermocouple sensor. Melting curve followed by gel electrophoresis is used to confirm product specificity after the PCR cycles.
在涉及DNA操作的芯片实验室系统中，使用聚合酶链式反应（PCR）在小体积内进行DNA扩增。对于几微升体积的液体，准确且可重复地测量和监测热分布变得困难，而这是成功扩增的基本要求。传统温度传感器要么不具有生物相容性，要么太大，因此放置在远离液体的位置，导致校准误差。在这项工作中，我们提出了一种基于荧光的检测技术，该技术完全具有生物相容性且能直接测量液体温度。在一个3微升的硅 - 玻璃微制造装置中使用非接触感应加热进行PCR演示，其温度通过嵌入传感器DNA中的SYBR green I染料分子的荧光反馈来控制。将该性能与使用热电偶传感器的温度反馈进行比较。PCR循环后，通过熔解曲线和凝胶电泳来确认产物特异性。
