title: Digital quantification of miRNA directly in plasma using integrated comprehensive droplet digital detection.
abstract: Quantification of miRNAs in blood can be potentially used for early disease detection, surveillance monitoring and drug response evaluation. However, quantitative and robust measurement of miRNAs in blood is still a major challenge in large part due to their low concentration and complicated sample preparation processes typically required in conventional assays. Here, we present the 'Integrated Comprehensive Droplet Digital Detection' (IC 3D) system where the plasma sample containing target miRNAs is encapsulated into microdroplets, enzymatically amplified and digitally counted using a novel, high-throughput 3D particle counter. Using Let-7a as a target, we demonstrate that IC 3D can specifically quantify target miRNA directly from blood plasma at extremely low concentrations ranging from 10s to 10 000 copies per mL in ≤3 hours without the need for sample processing such as RNA extraction. Using this new tool, we demonstrate that target miRNA content in colon cancer patient blood is significantly higher than that in healthy donor samples. Our IC 3D system has the potential to introduce a new paradigm for rapid, sensitive and specific detection of low-abundance biomarkers in biological samples with minimal sample processing.
authors.affiliation: Department of Chemistry, Beijing Key Laboratory for Analytical Methods and Instrumentation, Tsinghua University, Beijing, 100084, China. jhli@mail.tsinghua.edu.cn.
authors.forename: Kaixiang
authors.initials: K
authors.lastname: Zhang
authors.forename: Dong-Ku
authors.initials: DK
authors.lastname: Kang
authors.forename: M Monsur
authors.initials: MM
authors.lastname: Ali
authors.forename: Linan
authors.initials: L
authors.lastname: Liu
authors.forename: Louai
authors.initials: L
authors.lastname: Labanieh
authors.forename: Mengrou
authors.initials: M
authors.lastname: Lu
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Riazifar
authors.forename: Thi N
authors.initials: TN
authors.lastname: Nguyen
authors.forename: Jason A
authors.initials: JA
authors.lastname: Zell
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Digman
authors.forename: Enrico
authors.initials: E
authors.lastname: Gratton
authors.forename: Jinghong
authors.initials: J
authors.lastname: Li
authors.forename: Weian
authors.initials: W
authors.lastname: Zhao
mesh_terms: D001774:Blood Chemical Analysis / Q000295:instrumentation*; D003110:Colonic Neoplasms / Q000097:blood; D006801:Humans; D056656:Lab-On-A-Chip Devices; D057230:Limit of Detection; D035683:MicroRNAs / Q000097:blood*; D018511:Systems Integration
chemical_list: D035683:MicroRNAs; C487931:mirnlet7 microRNA, human