An electrochemiluminescent aptasensor for amplified detection of exosomes from breast tumor cells (MCF-7 cells) based on G-quadruplex/hemin DNAzymes. Issue 11 (14th May 2019)

• Record Type: Journal Article
• Authors: Qiao, Bin; Guo, Qunqun; Jiang, Juqian; Qi, Yunlong; Zhang, Hui; He, Bangshun; Cai, Chenxin; Shen, Jian
• Is Part Of: Analyst. Volume 144:Issue 11(2019)
• Page Start: 3668
• Page End: 3675
• Publication Date: 2019-05-14
• Subjects: Chemistry, Analytic -- Periodicals; 543
• DOI: 10.1039/c9an00181f
• Languages: English
• ISSNs: 0003-2654

Abstract

Abstract : An electrochemiluminescent aptasensor was developed for the sensitive detection of exosomes from breast tumor cells (MCF-7 cells). Abstract : Exosomes are non-invasive biomarkers for cancer diagnosis. Herein, we describe an electrochemiluminescent (ECL) aptasensor for the detection of exosomes from breast tumor cells. Mercaptopropionic acid (MPA)-modified Eu 3+ -doped CdS nanocrystals (MPA-CdS:Eu NCs) and H2 O2 were used as ECL emitters and coreactant, respectively. The exosomes are recognized and captured by the CD63 aptamer, and then form a G-quadruplex/hemin DNAzyme, which efficiently catalyzes the decomposition of H2 O2, resulting in the decreased ECL signal of MPA-CdS:Eu NCs. The exosomes from breast tumor cells (MCF-7 cells) can be detected in the range of 3.4 × 10 5 to 1.7 × 10 8 particles per mL. The limit of detection (LOD) was estimated to be 7.41 × 10 4 particles per mL at a signal-to-noise ratio of 3. The aptasensor has been successfully used to detect exosomes in the serum.