1. Nanobody-based immunosensor for the detection of H. pylori in saliva.
- Author
-
Ahmad MI, Amorim CG, Abu Qatouseh LF, and Montenegro MCBSM
- Subjects
- Humans, Immunoassay methods, Gold chemistry, Antibodies, Immobilized chemistry, Antibodies, Immobilized immunology, Antigens, Bacterial immunology, Antigens, Bacterial analysis, Antigens, Bacterial isolation & purification, Saliva microbiology, Saliva chemistry, Biosensing Techniques instrumentation, Helicobacter pylori immunology, Helicobacter pylori isolation & purification, Single-Domain Antibodies chemistry, Single-Domain Antibodies immunology, Helicobacter Infections diagnosis, Helicobacter Infections microbiology, Helicobacter Infections immunology, Electrochemical Techniques, Limit of Detection
- Abstract
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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF