Friedman N A, Meldrum D R
Department of Electrical Engineering, University of Washington, Seattle 98195-2500, USA.
Anal Chem. 1998 Jul 15;70(14):2997-3002. doi: 10.1021/ac971303n.
A system that performs rapid thermal cycling of microliter and smaller liquid volumes inside glass capillary tubes that have an optically transparent thin film of indium-tin oxide (ITO) covering the exterior is described. The ITO film acts as both a heater and a temperature sensor, while cooling is accelerated with forced air. Unlike existing batch-mode thermal cycling systems, this system allows control over each sample's temperature profile. Temperature transition rates of 44 degrees Celsius per second during heating and 15 degrees Celsius per second during cooling have been achieved, allowing successful polymerase chain reaction (PCR) experiments to be performed in 20 min. Capillary external temperature can be regulated typically to within +/- 0.25 degrees Celsius, and peak temperatures more than 800 degrees Celsius have been demonstrated. Capillary internal (sample) temperatures at present are controllable typically to within 2 degrees Celsius. The resistive film can be used as a temperature sensor, and the optical transparency of the thin-film coating could permit fluorescent monitoring of the sample during thermal cycling, making this method well suited for real-time quantitative PCRs.
描述了一种系统，该系统能在玻璃毛细管内对微升及更小体积的液体进行快速热循环，这些玻璃毛细管的外部覆盖有一层氧化铟锡（ITO）光学透明薄膜。ITO薄膜兼具加热器和温度传感器的功能，同时通过强制空气加速冷却。与现有的批处理模式热循环系统不同，该系统可对每个样品的温度曲线进行控制。加热过程中的温度转换速率达到每秒44摄氏度，冷却过程中为每秒15摄氏度，从而能在20分钟内成功进行聚合酶链反应（PCR）实验。毛细管外部温度通常可调节至±0.25摄氏度以内，并且已证明峰值温度超过800摄氏度。目前毛细管内部（样品）温度通常可控制在2摄氏度以内。电阻膜可用作温度传感器，薄膜涂层的光学透明性可允许在热循环期间对样品进行荧光监测，使得该方法非常适合实时定量PCR。
