Surface-enhanced Raman scattering biosensor-based sandwich-type for facile and sensitive detection of Staphylococcus aureus

• Published in: Sensors and actuators. B, Chemical Vol. 364; p. 131929
• Main Authors: Wei, Wenya, Haruna, Suleiman A., Zhao, Yumeng, Li, Huanhuan, Chen, Quansheng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2022
• Subjects: Core-shell nanoparticles; Polydimethylsiloxane; SERS; Staphylococcus aureus; Vancomycin; Core-shell nanoparticles; Vancomycin; SERS; Polydimethylsiloxane; Staphylococcus aureus
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2022.131929

Foodborne infections caused by Staphylococcus aureus (S. aureus) represent a serious health risk to the general public. In this study, we proposed a surface-enhanced Raman spectroscopy (SERS) biosensor based on a signal-amplification sandwich-type system for detecting and quantifying S. aureus. Herein, the SERS response of SiO2-coated Au@Ag was studied using Raman signals from Au@Ag@SiO2 nanoparticles and van grafted PDMS for the target acquisition. It has been shown that SiO2 coated Au@Ag exhibited a robust and strong response to SERS. Therefore, the combination of vancomycin (Van) and polydimethylsiloxane (PDMS) allowed a more efficient capture of S. aureus, resulting in improved repeatability through simplified separation procedures. Consequently, as a result of the presence of S. aureus targets, sandwich-type conjugate structures between the capture and signal units, as well as synergistic Raman amplification, were observed. Based on optimized conditions, a good linear correlation (y = 1087.86x - 540.75, R2 = 0.9958) in a wide dynamic range of 38–3.8 × 107 cfu·mL−1 was achieved with a limit of detection of 2 cfu·mL−1. The accuracy of the sensors was evaluated using a standard addition technique, and the results were satisfactory. Finally, the overall biosensor demonstrated potential application for monitoring S. aureus with good recoveries. [Display omitted] •A SERS-based sandwich-type biosensor was designed for S. aureus detection.•PDMS and Van as a capturing unit simplify the separation process.•The use of SiO2 shells improves the stability of the Au@Ag nanoparticles.•The designed sensor has a wide linear range and a low detection limit.