聚二甲基硅氧烷球形微腔阵列的数字PCR芯片

Digital PCR chip based on PDMS spherical cavity array

数字聚合酶链式反应(d PCR)技术是一种核酸绝对定量技术,但现有d PCR平台因其昂贵的设备或复杂的操作限制了其实际应用。利用气体膨胀浇注成型技术,结合集成微腔阵列的模具,设计、制作了一种成本低廉、简单可靠的d PCR微流控芯片。独特的球形微腔为液滴存储提供了更稳定的几何形式,保证了样品数字离散化的可靠性和稳定性。同时,芯片还利用预脱气的聚二甲基硅氧烷(PDMS)实现自动进样和样品离散化,大大降低了对复杂昂贵设备的依赖,且提供了更高集成度。利用芯片进行了EGFR基因第19号外显子数字PCR定量检测,验证了该芯片的实用性。

Digital polymerase chain reaction （dPCR）is a powerful method for the absolute quantification of nucleic acids. However, the available dPCR platforms require either expensive instruments or complicated operation,which limit their extensive applications. A simple, inexpensive and reliable dPCR microfluidic chip is designed and fabricated, using the gas expansion molding technique which is assisted by a silicon wafer mold containing arrays of deep etched pits. The novel spherical cavity can provide a stable accommodation for partitioned droplets, ensuring a reliable and robust discretization of samples. Furthermore, a degas-driven flow is used for self- priming and self-partition of samples, which significantly simplified the chip operation. Feasibility of the dPCR chip is demonstrated by accurately detecting EGFR exon 19.