数字微流控技术及其在生物分析中的应用

数字微流控技术是一种基于微电极阵列来实现离散液滴精确控制的新型液滴操纵技术。这种基于介电润湿现象实现的液滴电操纵体系,相比于传统微流控芯片具有自动化、可寻址、可动态配置、易集成等特点。该文介绍了数字微流控技术液滴驱动原理,总结了芯片的结构和常用的制作方法,举例阐述了现阶段该技术在生物分析化学领域的应用,并对其应用前景做了展望。国家自然科学基金资助项目(21735004,21435004,21775128,21705024,21521004);;长江学者和创新研究团队项目(IRT13036

Digital-WGS: Automated, highly efficient whole-genome sequencing of single cells by digital microfluidics

单细胞全基因组测序(whole-genome sequencing, WGS)是表征细胞内DNA动态变化的关键手段，可为我们提供全面、深度的生物学信息，是生命科学领域研究的热点。然而，单细胞全基因组测序仍面临着诸如样品制备复杂、成本高、扩增偏置性强、误差大的挑战。杨朝勇教授课题组搭建了基于数字微流控的单细胞操控与纳升级全基因组测序平台Digital-WGS，可用于一体化、全自动的单细胞处理与分析。通过Digital-WGS方法制备的单细胞样本在不同测序深度下均展示出了高均一性、高覆盖率、高准确性的优势，解决了当前单细胞基因组测序操作复杂、成本高、均一性差、准确度低等问题，为单细胞基因组测序的广泛应用提供了新的思路。 本研究工作在化学化工学院杨朝勇教授的指导下完成，2015级iChEM直博生阮庆宇为第一作者。Single-cell whole-genome sequencing (WGS) is critical for characterizing dynamic intercellular changes in DNA. Current sample preparation technologies for single-cell WGS are complex, expensive, and suffer from high amplification bias and errors. Here, we describe Digital-WGS, a sample preparation platform that streamlines high-performance single-cell WGS with automatic processing based on digital microfluidics. Using the method, we provide high single-cell capture efficiency for any amount and types of cells by a wetted hydrodynamic structure. The digital control of droplets in a closed hydrophobic interface enables the complete removal of exogenous DNA, sufficient cell lysis, and lossless amplicon recovery, achieving the low coefficient of variation and high coverage at multiple scales. The single-cell genomic variations profiling performs the excellent detection of copy number variants with the smallest bin of 150 kb and single-nucleotide variants with allele dropout rate of 5.2%, holding great promise for broader applications of single-cell genomics.We thank the National Natural Science Foundation of China (21927806, 21735004, 21521004, and 21325522), the National Key R&D Program of China (2018YFC1602900, 2019YFA0905800), Innovative Research Team of High-Level Local Universities in Shanghai (SSMU-ZLCX20180701), and the Program for Changjiang Scholars and Innovative Research Team in University (IRT13036) for financial support. 研究工作得到了国家自然科学基金(21927806、21735004、21521004、21325522), 国家重点研发项目(2018YFC1602900、2019YFA0905800)和教育部“长江学者和创新团队发展计划” (IRT13036)的资助与支持

Determination of the number of ψ(3686) events taken at BESIII

The number of ψ(3686) events collected by the BESIII detector during the 2021 run period is determined to be (2259.3±11.1)×106 by counting inclusive ψ(3686) hadronic events. The uncertainty is systematic and the statistical uncertainty is negligible. Meanwhile, the numbers of ψ(3686) events collected during the 2009 and 2012 run periods are updated to be (107.7±0.6)×106 and (345.4±2.6)×106, respectively. Both numbers are consistent with the previous measurements within one standard deviation. The total number of ψ(3686) events in the three data samples is (2712.4±14.3)×10^

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies