Nanobody-based immunosensor for the detection of <i>H. pylori</i> in saliva

• Type: Article in International Scientific Journal
• Date: 2024

Authors

Ahmad, MIA (Author) Other; Amorim, CG (Author) FFUP; Abu Qatouseh, LF (Author) Other; Montenegro, MCBSM (Author) FFUP

Journal

Title: Biosensors and Bioelectronics

Vol. 260

ISSN: 0956-5663

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 1 Citation

Other information

Authenticus ID: P-010-GHE

DOI: 10.1016/j.bios.2024.116423

Abstract (EN): Helicobacter pylori (H. pylori) infection is highly prevalent worldwide, affecting more than 43% of world population. The infection can be transmitted through different routes, like oral-oral, fecal-oral, and gastric-oral. Electrochemical sensors play a crucial role in the early detection of various substances, including biomolecules. In this study, the development of nanobody (Nb)-based immunosensor for the detection of H. pylori antigens in saliva samples was investigated. The D2_Nb was isolated and characterized using Western blot and ELISA and employed in the fabrication of the immunosensor. The sensor was prepared using gold screen-printed electrodes, with the immobilization of Nb achieved through chemical linkage using cysteamine-glutaraldehyde. The surface of the electrode was characterized using EIS, FTIR and SEM. Initially, the Nb-based immunosensor's performance was evaluated through cyclic voltammetry (CV), differential pulse voltammetry (DPV), and square wave voltammetry (SWV). The sensor exhibited excellent linearity with an R-2 value of 0.96. However, further assessment with the DPV technique revealed both a low limit of detection (5.9 ng/mL, <1 cfu/mL) and high selectivity when exposed to a mixture of similar antigens. Moreover, the immunosensor demonstrated robust recovery rates (96.2%-103.4%) when spiked into artificial saliva and maintained its functionality when stored at room temperature for 24 days.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12