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bioRxiv · 10.1101/2021.01.31.428989

A Facile and Rapid Route to Self-Digitization of Samples into a High Density Microwell Array for Digital Bioassays

Cui, X.·Hu, T.·Chen, Q.·Zhao, Q.·Wu, Y.·Xie, T.·Liu, P.·Su, X.·Li, G.
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Abstract

Digital bioassays are powerful methods to detect rare analytes from complex mixtures and study the temporal processes of individual entities within biological systems. In digital bioassays, a crucial first step is the discretization of samples into a large number of identical independent partitions. Here, we developed a rapid and facile sample partitioning method for versatile digital bioassays. This method is based on a detachable self-digitization (DSD) chip which couples a reversible assembly configuration and a predegassing-based self-pumping mechanism to achieve an easy, fast and large-scale sample partitioning. The DSD chip consists of a channel layer used for loading sample and a microwell layer used for holding the sample partitions. Benefitting from its detachability, the chip avoids a lengthy oil flushing process used to remove the excess sample in loading channels and can compartmentalize a sample into more than 100,000 wells of picoliter volume with densities up to 14,000 wells/cm2 in less than 30 s. We also demonstrated the utility of the proposed method by applying it to digital PCR and digital microbial assays.

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Cui, X., Hu, T., Chen, Q., Zhao, Q., Wu, Y., Xie, T., Liu, P., Su, X., Li, G.. 2021-02-01. A Facile and Rapid Route to Self-Digitization of Samples into a High Density Microwell Array for Digital Bioassays. https://doi.org/10.1101/2021.01.31.428989

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