透明导电玻璃(ITO)基材自加热传感静态芯片聚合酶链反应(PCR)

利用商品化ITO玻璃导电层的温阻效应, 无需任何微加工手段, 实现了自加热和传感的芯片温度自动程序控制, 最大程度地减小了传感滞后对温度控制稳定性的影响, 温度控制的稳定性达到了0.2 ℃, 升温速度最快可达20 ℃/s以上, 在冷却风扇辅助下降温速度最快达到了8 ℃/s. 芯片温控单元的引线从传统的两对(一对用于传感, 一对用于加热)减少为一对. 通过在该芯片上直接构建多个开放微池反应器的方法成功地实现了λDNA 157 bp片段的并行扩增. 将该芯片置于倒置荧光显微镜样品台上, 以蓝色(575 nm)发光二极管为光源, 以光电倍增管为检测手段检测了dsDNA和SYBR Green Ⅰ嵌合物的荧光强度随温度的实时变化曲线.

Self-heating and Sensing Static Chip Polymerase Chain Reaction (PCR) of Transparent Electro-conductive Glass Substrate (ITO)

Static chip polymerase chain reaction(PCR) needs no mechanical parts, and is easy to be integrated with chip separation and detection system, thus has a wider application in analysis field and POCT(point of care test). Chip thermal-time program control is crucial in static chip PCR, normally this is achieved with the aid of micro-fabrication technique in preparing the heating and sensing elements on chip. In this article, a thermostat chip that is capable of self-heating and sensing automatically and programmatically was established for the first time with commercial indium-tin oxide(ITO) glass substrate without involving any micro-fabrication process. The transparent and elelctro-conductive layer was used both as heating and temperature sensing elements, and time delay due to separate sensor is minimized. Electrical contacts is reduced from two couples(one for heating and one for sensing) to only one for each thermostat chip unit. The system has a control stability of 0.2 ℃, a maximum temperature ramping rate above 20 ℃/s and a cooling rate 8 ℃/s with the aid of a cooling fan. Multiple open reaction reservoirs can be constructed directly on the chip surface, and static chip PCR of a λDNA fragment(c.a. 157 bp) is successfully demonstrated. In-situ real-time fluorescence monitoring of a dsDNA and SYBR Green Ⅰ mixture during the temperature cycling was also demonstrated by placing the chip on the sample stage of an inverted fluorescence microscope that equipped with a blue light emission diode(575 nm) and a photomultiplier tube.