Spherical Nucleic Acid-Amplified Digital Flow Cytometric Bead Assay for the Ultrasensitive Detection of Protein and Exosome  

作　　者：Jingjing Shi Yuanyuan Sun Wenjiao Fan Wei Ren Chenghui Liu 

机构地区：[1]Key Laboratory of Applied Surface and Colloid Chemistry,Ministry of Education,Xi'an,Shaanxi710119,China [2]Key Laboratory of Analytical Chemistry for Life Science of Shaanxi rovince,Xi'an,Shaanxi710119,China [3]School of Chemistry&Chemical Engineering,Shaanxi Normal University,Xi'an,Shaanxi 710119,China [4]Department of TranslationalMedicine Center,The First Affiliated Hospital of Zhengzhou University,Zhengzhou,Henan 450052,China

出　　处：《Chinese Journal of Chemistry》2023年第17期2151-2158,共8页中国化学（英文版）

基　　金：supported by the National Natural Science Foundation of China(22074088,21622507);the Program for Changjiang Scholars and Innovative Research Team in University(IRT_15R43);the Fundamental Research Funds for the Central Universities(GK202101001,GK202206040);Innovation Capability Support Program of Shaanxi(2021TD-42).

摘　　要：Comprehensive Summary,Most conventional digital bioassays rely on the use of fully-sealed microchambers as independent units to compartmentalize the target molecules and the signal generation reaction,which require specialized equipment or proprietary reagents/consumables.Herein,we report a microchamber-free and spherical nucleic acid(SNA)-amplified digital flow cytometric bead assay(dFBA)for ultrasensitive protein and exosome analysis with simple workflows,easily accessible instruments/reagents,and high discriminating ability towards the fluorescence-positive and fluorescence-negative beads.In this dFBA,microbeads are employed as independent carriers to anchor the single target molecule-initiated signal amplification reaction,avoiding the use of sealed droplets or microwell microchambers.Meanwhile,antibody-functionalized SNAs(FSNAs)with a high density of DNA probes act as a bridge for efficiently amplified target-to-DNA signal conversion,which allows the use of DNA-based rolling circle amplification(RCA)as the fluorescence signal amplification technique to quantify non-nucleic acid targets.Even a single target-induced on-bead RCA and fluorescence enriching are sufficient to make the target-loaded bead bright enough to be clearly discriminated from the negative ones just by use of a most common flow cytometer(FCM).This dFBA has successfully realized the digital analysis of ultralow levels of protein and exosome biomarkers,enlarging the toolbox of digital bioassays for clinical applications.

关 键 词：Spherical nucleic acid Digital counting Flow cytometer IMMUNOASSAY EXOSOME Analytical methods BIOTECHNOLOGY Fluorescence 

分 类 号：O6[理学—化学]