State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Sci Rep. 2020 Oct 20;10(1):17824. doi: 10.1038/s41598-020-74711-8.
This paper presents a digital PCR system based on a novel thermal cycled chip, which wraps microchannels on a trapezoidal structure made of polydimethylsiloxane (PDMS) in a multi-helix manner for the first time. It is found that compared to the single helix chip commonly used in previous reports, this kind of novel multi-helix chip can make the surface temperature in the renaturation zone more uniform, and even in the case of rapid fluid flow, it can improve the efficiency of the polymerase chain reaction. What's more, the winding method of multi helix (such as double helix, six helix and eight helix) can obtain better temperature uniformity than the winding of odd helix (such as single helix and three helix). As a proof of concept, the temperature-optimized double-helical chip structure is applied to continuous-flow digital PCR and there is no need to add any surfactant to both the oil phase and reagent. In addition, we successfully analyzed the fluorescence signal of continuous-flow digital PCR by using CMOS camera. Finally, this method is applied for the absolute quantification of the clinical serum sample infected by HBV. The accuracy of the test results has been confirmed by commercial instruments.
本文提出了一种基于新型热循环芯片的数字 PCR 系统，该芯片首次以多螺旋方式将微通道包裹在聚二甲基硅氧烷（PDMS）制成的梯形结构上。研究发现，与之前报道中常用的单螺旋芯片相比，这种新型多螺旋芯片可以使复性区的表面温度更加均匀，即使在快速流体流动的情况下，也可以提高聚合酶链反应的效率。此外，多螺旋（如双螺旋、六螺旋和八螺旋）的缠绕方式比单螺旋（如单螺旋和三螺旋）的缠绕方式能获得更好的温度均匀性。作为概念验证，对经温度优化的双螺旋芯片结构应用于连续流数字 PCR，无需在油相和试剂中添加任何表面活性剂。此外，我们成功地使用 CMOS 相机对连续流数字 PCR 的荧光信号进行了分析。最后，该方法应用于 HBV 感染的临床血清样本的绝对定量，测试结果的准确性已得到商业仪器的验证。
