A facile and rapid route to self-digitization of samples into a high density microwell array for digital bioassays

• Published in: Talanta (Oxford) 2021-10, Vol.233, p.122589-122589, Article 122589
• Main Authors: Cui, Xu, Hu, Tianbao, Chen, Qiang, Zhao, Qiang, Wu, Yin, Xie, Tengbao, Liu, Pengyong, Su, Xi, Li, Gang
• Format: Article
• Language: English
• Subjects: Absolute quantification; Digital bioassay; High-density microwell array; Self-digitization; Single bacteria growth kinetics
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2021.122589

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 the 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. [Display omitted] •A facile, fast, and robust sample digitization (SD) method is developed.•A detachable channel-well configuration allows the fast removal of the excess sample.•Dead-end and outlet-free loading channels allow greater sample utilization.•Our SD chip can provide low-cost, rapid, and precise versatile digital bioassays.