Real-time pathogen monitoring during enrichment: a novel nanotechnology-based approach to food safety testing

Weidemaier, Kristin; Carruthers, Erin; Curry, Adam; Kuroda, Melody; Fallows, Eric; Thomas, Joseph; Sherman, Douglas B.; Muldoon, Mark T.

doi:10.1016/j.ijfoodmicro.2014.12.018

Cited by 43 publications

(19 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…When the detected concentrations are more realistic and the bacterial cells available for the detection are fewer, then the intensity of the detected Raman peaks diminishes and many of the peaks disappear from the spectrum. Another possibility for capturing bacteria is the use of immuno-magnetic separation beads which have been used in several Escherichia coli studies 34,35 and at least in one Listeria growth study 24 Figure 2 with the gold nanoparticles. In these cases the identification of the bacteria can be handled by pathogen-capture proteins while SERS is used for the detection.…”

Section: Methods For the Detection Of Listeria Innocuamentioning

confidence: 99%

“…Weidemaier et al 24 , has studied the detection of L. monocytogenes inside the food matrix with the help of immunomagnetic beads and nanoparticle SERS tags with antibodies, as they point out, the method is sensitive to the extent to which the magnetic particles can be concentrated within the area of the laser beam and care must be taken to succeed with reproducible pelleting of the magnetic particles. by mechanical methods, followed by culturing of the bacteria at elevated temperatures in the food matrix to accelerate the bacteria growth to a detectable level.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Detection of Listeria innocua on roll-to-roll produced SERS substrates with gold nanoparticles

et al. 2016

View full text Add to dashboard Cite

The rapid and accurate detection of food pathogens plays a critical role in the early prevention of foodborne epidemics.Current bacteria identification practises, including colony counting, polymerase chain reaction (PCR) and immunological methods, are time consuming and labour intensive; they are not ideal for achieving the required immediate diagnosis. Different SERS substrates have been studied for the detection of foodborne microbes. The majority of the approaches are either based on costly patterning techniques on silicon or glass wafers or on methods which have not been tested in large scale fabrication. We demonstrate the feasibility of analyte specific sensing using mass-produced, polymer-based low-cost SERS substrate in analysing the chosen model microbe with biological recognition. The use of this novel roll-to-roll fabricated SERS substrate was combined with optimised gold nanoparticles to increase the detection sensitivity.Distinctive SERS spectral bands were recorded for Listeria innocua ATCC 33090 using an in-house build (785 nm) near infra red (NIR) Raman system. Results were compared to both those found in the literature and the results obtained from a commercial time-gated Raman system with a 532 nm wavelength laser excitation. The effect of the SERS enhancer metal and the excitation wavelength on the detected spectra was found to be negligible. The hypothesis that disagreements within the literature regarding bacterial spectral results from conditions present during the detection process has not been supported. The sensitivity of our SERS detection was improved through optimization of the concentration of the sample inside the hydrophobic polydimethylsiloxane (PDMS) wells. Immuno-magnetic separation (IMS) beads were used to assist the accumulation of bacteria into the path of the beam of the excitation laser. With this combination we have detected L i s t e r i a w i t h g o l d e n h a n c e d S E R S i n a l a b e l f r e e m a n n e r f r o m s u c h l o w s a m p l e c o n c e n t r a t i o n s a s 1 0 4 CFU/ml.Figure 10. a) A normalised concentration series for LOD estimation. b) An exponential fit for the normalised concentration series in logarithmic scale for the entire series and a linear fit for the small concentrations. c) Comparison of the 737 cm -1 peak intensity for different concentration series with 5 -10 µl dried IMS bound L. innocua ATCC 33090 samples placed with AuNPs into a 1 -1.5 mm PDMS well on top of SERS substrate. d) Comparison of baseline corrected Raman intensities for three of the concentration series. All figures are a mean of 9 measurement points with mean absolute deviations.

show abstract

Section: Methods For the Detection Of Listeria Innocuamentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Detection of Listeria innocua on roll-to-roll produced SERS substrates with gold nanoparticles

et al. 2016

View full text Add to dashboard Cite

show abstract

“…GNPs offer inherent optical properties such as surface plasmon resonance (SPR) to monitor biomolecular interactions. GNPs conjugated with functional molecules have been used widely, such as colorimetric sensing of blood clotting enzyme, thrombin (Wei et al, 2007), drug delivery (Ghosh et al, 2008), cancer therapy (Peer et al, 2007), pathogen detection (Rossi et al, 2014;Weidemaier et al, 2015), and prostate cancer, and HIV protein detection (De La Rica and Stevens, 2012). GNP has been also used in the non-enzymatic electrochemical detection of sugars (Kurniawan et al, 2006) and active packaging in agri-food industry sector (Handford et al, 2014;Mihindukulasuriya and Lim, 2014).…”

Section: Introductionmentioning

confidence: 99%

Antilisterial and Antibiofilm Activities of Pediocin and LAP Functionalized Gold Nanoparticles

Singh

Bai

Amalaradjou

et al. 2018

Front. Sustain. Food Syst.

View full text Add to dashboard Cite

In this study, we synthesized and assessed the antilisterial and antibiofilm properties of a novel gold nanocomposite, functionalized with antimicrobial peptide, Pediocin AcH and Listeria adhesion protein (LAP) for targeted inactivation of L. monocytogenes. The gold nanoparticle (GNP) and the gold nanocomposites (GNP-Pediocin-LAP) were characterized using spectroscopic and transmission electron microscopy (TEM) and their effect on human enterocyte-like Caco-2 cells were assessed by lactate dehydrogenase (LDH)-based cytotoxicity and inhibition of Listeria adhesion assay. The antilisterial and antibiofilm activities of nanocomposites on L. monocytogenes were determined by a plating method. TEM image analysis indicated that the size of GNP and the gold nanoconjugates to be about 20 and 40 nm, respectively; and spectroscopy indicated the successful loading of proteins onto citrate-stabilized GNPs. Gold nanocomposites were non-toxic and significantly reduced L. monocytogenes adhesion to Caco-2 cells. Relative to the GNP-Pediocin conjugate, the GNP-Pediocin-LAP conjugate showed 11.1% higher zone of inhibition in agar diffusion assay, and higher reduction (1.5 log 10 CFU/mL) in L. monocytogenes counts. Same preparation also showed 24 and 31% more reduction in Listeria counts in biofilms after 24 and 48 h of incubation, respectively. Nanocomposites were also highly effective in decontamination of L. monocytogenes on a miniature industrial conveyor system. Altogether, co-action of Pediocin and the LAP functionalized on GNP (GNP-Pediocin-LAP), demonstrated higher antilisterial and antibiofilm activities compared to the Pediocin functionalized GNP or Pediocin alone suggesting GNP can provide a platform to load multiple proteins for surface decontamination of L. monocytogenes in industrial settings.

show abstract

“…Assay reagents and disposable design SERS nanotags were synthesized by BD (Research Triangle Park, NC) according to methods described previously (10,11,37) and using the following Raman dyes: 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (Tag 493; catalog no. 10650010, Acros Organics), 4,4′-dipyridyl (Tag 420; catalog no.…”

Section: Malaria Assay Testingmentioning

confidence: 99%

A point-of-care diagnostic for differentiating Ebola from endemic febrile diseases

et al. 2018

Self Cite

View full text Add to dashboard Cite

Hemorrhagic fever outbreaks such as Ebola are difficult to detect and control because of the lack of low-cost, easily deployable diagnostics and because initial clinical symptoms mimic other endemic diseases such as malaria. Current molecular diagnostic methods such as polymerase chain reaction require trained personnel and laboratory infrastructure, hindering diagnostics at the point of need. Although rapid tests such as lateral flow can be broadly deployed, they are typically not well-suited for differentiating among multiple diseases presenting with similar symptoms. Early detection and control of Ebola outbreaks require simple, easy-to-use assays that can detect and differentiate infection with Ebola virus from other more common febrile diseases. Here, we developed and tested an immunoassay technology that uses surface-enhanced Raman scattering (SERS) tags to simultaneously detect antigens from Ebola, Lassa, and malaria within a single blood sample. Results are provided in <30 min for individual or batched samples. Using 190 clinical samples collected from the 2014 West African Ebola outbreak, along with 163 malaria positives and 233 negative controls, we demonstrated Ebola detection with 90.0% sensitivity and 97.9% specificity and malaria detection with 100.0% sensitivity and 99.6% specificity. These results, along with corresponding live virus and nonhuman primate testing of an Ebola, Lassa, and malaria 3-plex assay, indicate the potential of the SERS technology as an important tool for outbreak detection and clinical triage in low-resource settings.

show abstract

Real-time pathogen monitoring during enrichment: a novel nanotechnology-based approach to food safety testing

Cited by 43 publications

References 21 publications

Detection of Listeria innocua on roll-to-roll produced SERS substrates with gold nanoparticles

Detection of Listeria innocua on roll-to-roll produced SERS substrates with gold nanoparticles

Antilisterial and Antibiofilm Activities of Pediocin and LAP Functionalized Gold Nanoparticles

A point-of-care diagnostic for differentiating Ebola from endemic febrile diseases

Contact Info

Product

Resources

About