Architecting of an aptasensor for the staphylococcus aureus analysis by modification of the screen-printed carbon electrode with aptamer/Ag-Cs-Gr QDs/NTiO2

Masoumeh Ghalkhani; Esmail Sohouli; Shokooh Sadat Khaloo; Mohammad Hossein Vaziri

doi:10.1016/j.chemosphere.2022.133597

Architecting of an aptasensor for the staphylococcus aureus analysis by modification of the screen-printed carbon electrode with aptamer/Ag-Cs-Gr QDs/NTiO₂

Chemosphere. 2022 Apr:293:133597. doi: 10.1016/j.chemosphere.2022.133597. Epub 2022 Jan 11.

Authors

Masoumeh Ghalkhani¹, Esmail Sohouli², Shokooh Sadat Khaloo³, Mohammad Hossein Vaziri⁴

Affiliations

¹ Electrochemical Sensors Research Laboratory, Department of Chemistry, Faculty of Science, Shahid Rajaee Teacher Training University, Lavizan, P.O. Box 1678815811, Tehran, Iran. Electronic address: ghalkhani@sru.ac.ir.
² Electrochemical Sensors Research Laboratory, Department of Chemistry, Faculty of Science, Shahid Rajaee Teacher Training University, Lavizan, P.O. Box 1678815811, Tehran, Iran.
³ Workplace Health Promotion Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Health, Safety and Environment, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address: sh_khaloo@sbmu.ac.ir.
⁴ Workplace Health Promotion Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Health, Safety and Environment, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

PMID: 35031253
DOI: 10.1016/j.chemosphere.2022.133597

Abstract

Given the many issues bacterial infections cause to humans and the necessity for their detection, in this work we developed a robust aptasensor for prompt, ultrasensitive, and selective analysis of staphylococcus aureus bacterium (S. aureus). A nanocomposite of Ag nanoparticles, chitosan, graphene quantum dots, and nitrogen-doped TiO₂ nanoparticles (Ag-Cs-Gr QDs/NTiO₂) was synthesized, and thoroughly characterized by XRD, FT-IR, and FE-SEM spectroscopic methods. The surface of screen-printed carbon electrodes modified with Ag-Cs-Gr QDs/NTiO₂ nanocomposite was utilized as a compatible platform for aptamer attachment. The aptasensor accurately determined S. aureus in the dynamic range of 10-5 × 10⁸ CFU/mL with detection limit of 3.3 CFU/mL. The monitoring of the practical performance of aptasensor in human serum samples revealed its superiority over the conventional methods (relative recovery of 96.25-103.33%). The Ag-Cs-Gr QDs/NTiO₂-based aptasensor offers facile, biocompatibility, good repeatability, reproducibility (RSD = 3.66%), label free and stabile strategy for sensitive S. aureus analysis free from biomolecules interferences in actual specimens.

Keywords: Aptamer; Electrochemical; Graphene quantom dot; Silver nanoparticles; Staphylococcus aureus.

MeSH terms

Aptamers, Nucleotide* / chemistry
Biosensing Techniques* / methods
Carbon / chemistry
Electrochemical Techniques / methods
Electrodes
Humans
Limit of Detection
Metal Nanoparticles* / chemistry
Reproducibility of Results
Silver / chemistry
Spectroscopy, Fourier Transform Infrared
Staphylococcus aureus

Substances

Aptamers, Nucleotide
Silver
Carbon