Investigation of factors that impact the label-free surface-enhanced Raman scattering (SERS) for the detection and discrimination of Salmonella Enteritidis. (October 2021)

• Record Type: Journal Article
• Authors: Chuesiang, Piyanan; Ryu, Victor; Siripatrawan, Ubonrat; McLandsborough, Lynne; He, Lili
• Is Part Of: Lebensmittel-Wissenschaft + Technologie =. Volume 150(2021)
• Publication Date: 2021-10
• Subjects: Rapid method -- Bacterial discrimination -- Coffee ring effect -- SERS -- Raman spectroscopy; Food industry and trade -- Periodicals; Food -- Composition -- Periodicals; Microbiology -- Periodicals; Nutrition -- Periodicals; 664.005
• DOI: 10.1016/j.lwt.2021.111962
• Languages: English
• ISSNs: 0023-6438

Abstract

Abstract: A simple and rapid label-free surface-enhanced Raman scattering (SERS) method involving silver nanoparticles, was developed to detect and discriminate Salmonella Enteritidis ( S . Enteritidis) not only at a specie ( Escherichia coli O157: H7; E. coli O157: H7), or a serovar level ( Salmonella Gaminara; S . Gaminara) but also between the viable and non-viable state of bacteria. Parameters that influenced the bacterial spectra were optimized, such as particle size of silver nanosphere and type of silver nanosphere's coating agent. The signal intensity of the spectra of bacteria was dependent on the particle size of the silver nanospheres. Whereas the patterns of different bacterial spectra varied based upon the silver nanosphere's coating agent. In this study, citrate-silver nanosphere (C-AgNPs) successfully discriminated the spectral data of S. Enteritidis from those of E. coli O157: H7, S. Gaminara, and non-viable S. Enteritidis when analyzed using principal component analysis (PCA) and linear discriminant analysis (LDA) of full-spectrum contribution. The method allowed the detection of S. Enteritidis to the concentration of 4 log CFU/mL. These results indicated the efficacy of the developed label-free SERS technique for the rapid detection and discrimination of S. Enteritidis from other closely related bacteria. Highlights: Silver nanosphere can discriminate S. Enteritidis at a specie and serovar level. Silver nanosphere can discriminate between viable and non-viable state of bacteria. Particle size and coating agent type affected Raman spectral fingerprints of bacteria. The label-free SERS can rapidly detect S. Enteritidis at the level of 4 log CFU/mL.