SERS-Based Lateral Flow Strip Biosensor for Simultaneous Detection of Listeria monocytogenes and Salmonella enterica Serotype Enteritidis

Abstract

Rapid, sensitive, point-of-care detection of bacteria is extremely important in food safety. To address this requirement, we developed a new surface-enhanced Raman scattering (SERS)-based lateral flow (LF) strip biosensor combined with recombinase polymerase amplification (RPA) for simultaneous detection of Listeria monocytogenes and Salmonella enterica serotype Enteritidis. Au@Ag core-shell nanoparticles were used in this SERS-LF. Highly sensitive quantitative detection is achieved by measuring the characteristic peak intensities of SERS tags. Under optimal conditions, the SERS intensities of MBA at 1077 cm on test lines are used to measure S. Enteritidis (y = 1980.6x - 539.3, R = 0.9834) and L. monocytogenes (y = 1696.0x - 844, R = 0.9889), respectively. The limit of detection is 27 CFU/mL for S. Enteritidis and 19 CFU/mL for L. monocytogenes. Significantly, this SERS-LF has high specificity and applicability in the detection of L. monocytogenes and S. Enteritidis in food samples. Therefore, the SERS-LF is a feasible method for the rapid and quantitative detection of a broad range of bacterial pathogens in real food samples.

Review: a comprehensive summary of a decade development of the recombinase polymerase amplification

“…However, the highest level of multiplexing is a triplex assay demonstrated by Piepenburg and co-workers for the detection of MRSA I, II and III genotypes (detection limits are 10 genomic copies each). 6 For single-tube multiplex RPA using multiple different nucleic acid templates, a few duplex and triplex assays have been demonstrated for the detection of bacteria, 126,188,189 parasites, 105 fungus, 98 genetic modified soybeans 21 and prostate cancer biomarkers. 179 In particular, Song and co-workers demonstrated the highest multiplexity via a 16-plex assay for pathogen detection by combing RPA reactions with LAMP on a microchip, which was termed a two-stage isothermal amplification (Fig.…”

Functionalized AuMBA@Ag Nanoparticles as an Optical and SERS Dual Probe in a Lateral Flow Strip for the Quantitative Detection of Escherichia coli O157:H7

“…The AuNPs and Au MBA @Ag SERS nanotags were synthesized as described in our previous paper (H. B. Liu, Du, Zang, Li, & Wang, 2017), and the preparation procedure is presented in Figure 1A. The colloidal gold was first synthesized via the well-established citrate-reduction method (Frens, 1973) and was used as the template for the synthesis of Au MBA @Ag nanotags.…”

<p>Current and Future Perspectives on Isothermal Nucleic Acid Amplification Technologies for Diagnosing Infections</p>

“…Some systems have been developed in a bid to making RPA an applicable on-demand testing method. These include digital RPA known as the slipchip 96,97 and microchip; 98 multiplex RPA for bacteria namely Salmonella spp and Chronobacter spp, 99 Listeria monocytogenes and Salmonella enterica serotype Enteritidis, 100 Group B streptococci; 101 parasites (Giardia, Cryptosporidium, and Entamoeba) 102 and fungus (Botrytis cinerea, Pseudomonas syringae, and Fusarium oxysporum); 103 mobile RPA in a suitcase which was named diagnostics-in-a-suitcase (Dias); 104,105 microfluidic integrated RPA; [106][107][108][109] and the one-step RPA assay. 110 While a slip chip is microfluidic device lacking pumps and valves, a microchip contains pumps and valves that aid movement of sample and reaction reagents through channels linking reaction chambers.…”