Sample digital technology is a powerful method for absolute quantification of target molecules such as nucleic acids and proteins. The excellent sample stability and mass production capability has enabled the development of microwell array-based sample digitizing methods. However, in current microwell array chips, samples are loaded by the liquid scraping method, which requires complex manual operation and results in a low filling rate and limited hole filling uniformity. Here, we perform sample loading of a through-hole array chip by a microfluidics-driven method and design a double independent S-shaped flow channels sandwiched through-hole array chip. Because of the capillary force and capillary burst pressure, the sample flowing in the channel can be trapped into through-holes, but cannot flow through the other side. Via air flow and displacement of the remaining sample in the channel, the sample can be partitioned consistently, with zero surplus sample residue in the channel. We evaluated the actual performance of the sample-loading process: the chip enables 99.10% filling rate of 18 500 through-holes, with a grayscale coefficient of variation value of 6.03% determined from fluorescence images. In performing digital polymerase chain reaction on chip, the chip demonstrates good performance for the absolute quantification of target DNA. The simple and robust design of our chip, with excellent filling rate and microsample uniformity, indicates potential for use in a variety of sample digitization applications.

中文翻译：

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具有双独立S形流道的高填充率数字PCR通孔阵列芯片。

样品数字技术是一种绝对定量分析目标分子（例如核酸和蛋白质）的有力方法。出色的样品稳定性和批量生产能力使得能够开发基于微孔阵列的样品数字化方法。然而，在当前的微孔阵列芯片中，样品是通过液体刮削法装载的，这需要复杂的手动操作，并且导致低的填充率和有限的孔填充均匀性。在这里，我们通过微流体驱动方法执行通孔阵列芯片的样品加载，并设计一个夹在通孔阵列芯片中的双独立S形流道。由于毛细作用力和毛细破裂压力，在通道中流动的样品可以被捕获到通孔中，但不能流过另一侧。通过气流和通道中剩余样品的置换，可以对样品进行均匀分配，通道中的残留样品为零。我们评估了样品加载过程的实际性能：该芯片可实现18.500个通孔的99.10％填充率，并且根据荧光图像确定的灰度变异系数值为6.03％。在芯片上进行数字聚合酶链反应时，该芯片表现出了对目标DNA绝对定量的良好性能。我们芯片的简单而坚固的设计，具有出色的填充率和微量样品的均一性，表明了在各种样品数字化应用中使用的潜力。我们评估了样品加载过程的实际性能：该芯片可实现18.500个通孔的99.10％填充率，并且根据荧光图像确定的灰度变异系数值为6.03％。在芯片上进行数字聚合酶链反应时，该芯片表现出了对目标DNA绝对定量的良好性能。我们芯片的简单而坚固的设计，具有出色的填充率和微量样品的均一性，表明了在各种样品数字化应用中使用的潜力。我们评估了样品加载过程的实际性能：该芯片可实现18.500个通孔的99.10％填充率，并且根据荧光图像确定的灰度变异系数值为6.03％。在芯片上进行数字聚合酶链反应时，该芯片表现出了对目标DNA绝对定量的良好性能。我们芯片的简单而坚固的设计，具有出色的填充率和微量样品的均一性，表明了在各种样品数字化应用中使用的潜力。该芯片证明了对目标DNA绝对定量的良好性能。我们芯片的简单而坚固的设计，具有出色的填充率和微量样品的均一性，表明了在各种样品数字化应用中使用的潜力。该芯片证明了对目标DNA绝对定量的良好性能。我们芯片的简单而坚固的设计，具有出色的填充率和微量样品的均一性，表明了在各种样品数字化应用中使用的潜力。