A highly sensitive electrochemical aptasensor for detection of microcystin-LR based on a dual signal amplification strategy. Issue 5 (17th January 2019)

• Record Type: Journal Article
• Authors: Liu, Xiaoqiang; Tang, Yunfei; Liu, Peipei; Yang, Liwei; Li, Lele; Zhang, Qingyou; Zhou, Yanmei; Khan, Md. Zaved Hossain
• Is Part Of: Analyst. Volume 144:Issue 5(2019)
• Page Start: 1671
• Page End: 1678
• Publication Date: 2019-01-17
• Subjects: Chemistry, Analytic -- Periodicals; 543
• DOI: 10.1039/c8an01971a
• Languages: English
• ISSNs: 0003-2654

Abstract

Abstract : In this work, a sensitive and selective electrochemical aptasensor for detection of microcystin-LR was developed based on a dual signal amplification system consisted of a novel ternary composite and horseradish peroxidase. Abstract : In this work, a sensitive and selective electrochemical aptasensor for determination of microcystin-LR (MC-LR) was developed based on a dual signal amplification system consisting of a novel ternary composite and horseradish peroxidase (HRP). The ternary composite was prepared by depositing gold nanoparticles (AuNPs) on molybdenum disulfide (MoS2 ) covered TiO2 nanobeads (TiONBs). MoS2 nanosheet modified TiONBs provided a large surface area for immobilization of AuNPs and biomolecules. The ternary composite also possesses an improved electron transfer and catalytic capability. To construct the aptasensor, thiolated MC-LR aptamers were immobilized on the AuNP@MoS2 -TiONB modified electrode through a gold–sulfur bond. Then, biotin–cDNA with a sequence complementary to the MC-LR aptamer competed with MC-LR for binding to the immobilized aptamer. The current signal catalyzed by avidin–HRP decreased with the increase of MC-LR, based on which a linear range of 0.005–30 nM and a detection limit of 0.002 nM were obtained.