Gold nanoparticle-engineered electrochemical aptamer biosensor for ultrasensitive detection of thrombin. Issue 29 (10th July 2020)

• Record Type: Journal Article
• Authors: Chen, Ying; Xiang, Junyi; Liu, Bin; Chen, Zhengbo; Zuo, Xia
• Is Part Of: Analytical methods. Volume 12:Issue 29(2020)
• Page Start: 3729
• Page End: 3733
• Publication Date: 2020-07-10
• Subjects: Chemistry, Analytic -- Periodicals; Analytical biochemistry -- Periodicals; Chemical laboratories -- Standards -- Periodicals; 543.1905
• DOI: 10.1039/d0ay01163k
• Languages: English
• ISSNs: 1759-9660

Abstract

Abstract : An electrochemical aptasensor for the ultrasensitive determination of TB based on sandwich-type structure-triggered signal amplification. Abstract : In order to obtain a lower detection limit in electrochemical detection, the choice of signal amplification strategy is of great importance. In this work, we describe an electrochemical sandwich aptasensor based on a signal amplification system involving two thrombin (TB) aptamers (TBA1 and TBA2), gold nanoparticles (AuNPs) as aptamer carriers, and [Ru(NH3 )6 ] 3+ for signal conversion. In the presence of the target thrombin, TBA1 and TBA2 specifically bind to TB, and the TBA1–TB–TBA2 complexes cause the formation of a sandwich structure, meaning more [Ru(NH3 )6 ] 3+ can be adsorbed on the negatively charged phosphate backbone of the aptamers, resulting in an increase in the differential pulse voltammetry (DPV) current. Under optimal conditions, the aptasensor exhibited a linear range of 1 fM to 6 pM and a limit of detection of 0.1429 fM (S/N = 3) for TB. The proposed aptasensor displayed an excellent selectivity and reproducibility. Importantly, the aptasensor was capable of detecting TB in serum samples successfully.