聚二甲基硅氧烷球形微腔阵列的数字PCR芯片

摘要

数字聚合酶链式反应(dPCR)技术是一种核酸绝对定量技术,但现有dPCR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dPCR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.