En Filter-baserte Surface Enhanced Raman Spektroskopiske analyse for rask påvisning av kjemiske forurensninger
Summary
En fremgangsmåte for fremstilling og utførelse av filterbaserte overflate forbedret Raman-spektroskopi (SERS) assay for påvisning av kjemiske forurensninger (dvs. plantevernmidler ferbam og antibiotika ampicillin) er presentert.
Abstract
We demonstrate a method to fabricate highly sensitive surface-enhanced Raman spectroscopic (SERS) substrates using a filter syringe system that can be applied to the detection of various chemical contaminants. Silver nanoparticles (Ag NPs) are synthesized via reduction of silver nitrate by sodium citrate. Then the NPs are aggregated by sodium chloride to form nanoclusters that could be trapped in the pores of the filter membrane. A syringe is connected to the filter holder, with a filter membrane inside. By loading the nanoclusters into the syringe and passing through the membrane, the liquid goes through the membrane but not the nanoclusters, forming a SERS-active membrane. When testing the analyte, the liquid sample is loaded into the syringe and flowed through the Ag NPs coated membrane. The analyte binds and concentrates on the Ag NPs coated membrane. Then the membrane is detached from the filter holder, air dried and measured by a Raman instrument. Here we present the study of the volume effect of Ag NPs and sample on the detection sensitivity as well as the detection of 10 ppb ferbam and 1 ppm ampicillin using the developed assay.
Introduction
Surface forbedret Raman-spektroskopi (SERS) er en teknikk som kombinerer Raman-spektroskopi med nanoteknologi. Intensiteten av Raman spredning av analytter på edle metallnano overflater er betydelig forbedret ved lokalisert overflate plasmon resonans. 1 sølv nanopartikler (Ag NPS) er den klart mest brukte SERS underlag på grunn av sin høye ekstrautstyr evne. 2 Opp til nå , forskjellige syntetiske fremgangsmåter for Ag NPS er blitt utviklet. 3-6 Ag NPS kan anvendes alene som effektive SERS substrater, eller kombinert med andre materialer og strukturer for å øke dets følsomhet, og / eller funksjonalitet. 7-11
SERS teknikker har vist stor kapasitet for påvisning av forskjellige spormengde forurensninger i mat og miljøprøver 12 Tradisjonelt er det to vanlige måter for fremstilling av en SERS prøve:.. Løsningsbasert og substrat-baserte metoder 13 Løsningen basert metod bruker NP kolloider å blande med prøver. Deretter NP-analytt komplekset er oppsamlet ved hjelp av sentrifugering, og avsatt på en fast bærer for Raman-måling etter tørking. Substratet basert metode påføres vanligvis ved å avsette flere mikroliter flytende prøve på den pre-fabrikerte fast substrat. 14 Men ingen av disse to metodene er effektive og anvendelig for en stor mengde av prøvevolum. Flere modifikasjoner av de SERS analysene vant volum begrensninger, for eksempel integrering av et filtersystem 15-21 eller inkorporering av en mikrofluidteknisk enhet. 21-24 De modifiserte SERS analyser har vist stor forbedring i følsomhet og muligheten for å overvåke de kjemiske forurensninger i store vannprøver.
Her viser vi detaljert protokoll for fabrikasjon og anvendelse av en sprøyte filter basert SERS metode for å påvise spor mengde plantevernmiddel ferbam og antibiotika ampicillin.
Protocol
Representative Results
Discussion
En av de kritiske trinn i denne protokollen er Ag NPs syntese, hvor ensartede Ag NPs er nøkkelen for konsistente resultater. Oppvarmingstiden og konsentrasjonen av forløperne må være nøyaktig kontrollert. Den gjennomsnittlige størrelsen på denne AgNPs preparat er 80 nm, som ble målt ved Zetasizer (data ikke vist). Et annet kritisk punkt er saltet aggregering hvor saltkonsentrasjonen og aggregering tid må kontrolleres nøyaktig. I tillegg, er valget av membran er også viktig ettersom membranen med en mindre por…
Disclosures
The authors have nothing to disclose.
Acknowledgements
This material is based upon work supported by the U.S. Department of Homeland Security under Grant Award Number 2010-ST-061-FD0001 through a grant awarded by the National Center for Food Protection and Defense at the University of Minnesota. Disclaimer: The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Department of Homeland Security or the National Center for Food Protection and Defense.
Materials
| Ampicillin | Fisher Scientific | BP1760-5 | N/A |
| Ferbam | Chem Service | N-11970-250MG | 98+% |
| Silver nitrate | Sigma Aldrich | 209139 | 99.0+% |
| Sodium citrate dehydrate | Sigma Aldrich | W302600 | 99+% |
| Sodium chloride | Sigma Aldrich | S7653 | 99.5+% |
| EMD Millipore Durapore PVDF Membrane Filters | Fisher Scientific | VVLP01300 | 0.10 µm Pore Size, hydrophilic |
| Polycarbonate Filter Holders | Cole-Parmer | EW-29550-40 | 13 mm diameter |
| Analog Vortex Mixer | Fisher Scientific | 02-215-365 | N/A |
| Nutating Mixers | Fisher Scientific | 05-450-213 | N/A |
| DXR Raman spectroscope | Thermo Scientific | IQLAADGABFFAHCMAPB | Laser power: 1 mW Exposure time: 5 s |
References
- Albrecht, M. G., Creighton, J. A. Anomalously intense Raman spectra of pyridine at a silver electrode. J. Am. Chem. Soc. 99 (15), 5215-5217 (1977).
- Schatz, G. C., Young, M. A., Van Duyne, R. P. . Electromagnetic mechanism of SERS. Surface-enhanced Raman scattering. , 19-45 (2006).
- Matijevic, E. Preparation and properties of uniform size colloids. Chem. Mater. 5 (4), 412-426 (1993).
- Nickel, U., zu Castell, A., Pöppl, K., Schneider, S. A silver colloid produced by reduction with hydrazine as support for highly sensitive surface-enhanced Raman spectroscopy. Langmuir. 16 (23), 9087-9091 (2000).
- Khanna, P. K., Subbarao, V. V. V. S. Nanosized silver powder via reduction of silver nitrate by sodium formaldehydesulfoxylate in acidic pH medium. Mater. Lett. 57 (15), 2242-2245 (2003).
- Henglein, A., Giersig, M. Formation of colloidal silver nanoparticles: capping action of citrate. J. Phys. Chem. B. 103 (44), 9533-9539 (1999).
- Sun, X., Li, Y. Colloidal carbon spheres and their core/shell structures with noble-metal nanoparticles. Angew. Chem. Int. Edit. 43 (5), 597-601 (2004).
- Lu, L., et al. Seed-mediated growth of large, monodisperse core-shell gold-silver nanoparticles with Ag-like optical properties. Chem. Commun. (2), 144-145 (2002).
- Aslan, K., Wu, M., Lakowicz, J. R., Geddes, C. D. Fluorescent core-shell Ag@SiO2 nanocomposites for metal-enhanced fluorescence and single nanoparticle sensing platforms. J. Am. Chem. Soc. 129 (6), 1524-1525 (2007).
- Lu, Y., Yin, Y., Li, Z. Y., Xia, Y. Synthesis and self-assembly of Au@ SiO2 core-shell colloids. Nano. Lett. 2 (7), 785-788 (2002).
- Link, S., Wang, Z. L., El-Sayed, M. A. Alloy formation of gold-silver nanoparticles and the dependence of the plasmon absorption on their composition. J. Phys. Chem. B. 103 (18), 3529-3533 (1999).
- He, L., et al. Rapid Detection of Ricin in Milk Using Immunomagnetic Separation Combined with Surface Enhanced Raman Spectroscopy. J. Food. Sci. 76 (5), N49-N53 (2011).
- Zheng, J., He, L. Surface-Enhanced Raman Spectroscopy for the Chemical Analysis of Food. Compr. Rev. Food. Sci. F. 13 (3), 317-328 (2014).
- He, L., Haynes, C. L., Diez-Gonzalez, F., Labuza, T. P. Rapid detection of a foreign protein in milk using IMS-SERS. J. Raman. Spectrosc. 42 (6), 1428-1434 (2011).
- Wei, W. Y., White, I. M. A simple filter-based approach to surface enhanced Raman spectroscopy for trace chemical detection. Analyst. 137 (5), 1168-1173 (2012).
- Cheng, M. L., Tsai, B. C., Yang, J. Silver nanoparticle-treated filter paper as a highly sensitive surface-enhanced Raman scattering (SERS) substrate for detection of tyrosine in aqueous solution. Anal. Chim. Acta. 708 (1), 89-96 (2011).
- Fierro-Mercado, P. M., Hernández-Rivera, S. P. Highly sensitive filter paper substrate for SERS trace explosives detection. Int. J. Spectrosc. 2012, 716527 (2012).
- Tran, C. D. Subnanogram detection of dyes on filter paper by surface-enhanced Raman scattering spectrometry. Anal. Chem. 56 (4), 824-826 (1984).
- Wu, D., Fang, Y. The adsorption behavior of p-hydroxybenzoic acid on a silver-coated filter paper by surface enhanced Raman scattering. J. Colloid Interface Sci. 265 (2), 234-238 (2003).
- Wigginton, K. R., Vikesland, P. J. Gold-coated polycarbonate membrane filter for pathogen concentration and SERS-based detection. Analyst. 135 (6), 1320-1326 (2010).
- Berthod, A., Laserna, J. J., Winefordner, J. D. Analysis by surface enhanced Raman spectroscopy on silver hydrosols and silver coated filter papers. J Pharm Biomed Anal. 6 (6), 599-608 (1988).
- Ackermann, K. R., Henkel, T., Popp, J. Quantitative Online Detection of Low-Concentrated Drugs via a SERS Microfluidic System. ChemPhysChem. 8 (18), 2665-2670 (2007).
- Walter, A., März, A., Schumacher, W., Rösch, P., Popp, J. Towards a fast, high specific and reliable discrimination of bacteria on strain level by means of SERS in a microfluidic device. Lab. Chip. 11 (6), 1013-1021 (2011).
- Lee, S., et al. Fast and sensitive trace analysis of malachite green using a surface-enhanced Raman microfluidic sensor. Anal. Chim. Acta. 590 (2), 139-144 (2007).
- Guo, H., et al. Analysis of Silver Nanoparticles in Antimicrobial Products Using Surface-Enhanced Raman Spectroscopy (SERS). Environ. Sci. Technol. 49 (7), 4317-4324 (2015).
- Narayanan, V. A., Begun, G. M., Stokes, D. L., Sutherland, W. S., Vo-Dinh, T. Normal Raman and surface enhanced Raman scattering (SERS) spectra of some fungicides and related chemical compounds. J. Raman. Spectrosc. 23 (5), 281-286 (1992).
- Kang, J. S., Hwang, S. Y., Lee, C. J., Lee, M. S. SERS of dithiocarbamate pesticides adsorbed on silver surface; thiram. Bull. Korean. Chem. Soc. 23 (11), 1604-1610 (2002).
- Li, Y. T., et al. Rapid and sensitive in-situ detection of polar antibiotics in water using a disposable Ag-graphene sensor based on electrophoretic preconcentration and surface-enhanced Raman spectroscopy. Biosens. Bioelectron. 43, 94-100 (2013).
- Clarke, S. J., Littleford, R. E., Smith, W. E., Goodacre, R. Rapid monitoring of antibiotics using Raman and surface enhanced Raman spectroscopy. Analyst. 130 (7), 1019-1026 (2005).
- Zheng, J., Pang, S., Labuza, T. P., He, L. Semi-quantification of surface-enhanced Raman scattering using a handheld Raman spectrometer: a feasibility study. Analyst. 138 (23), 7075-7078 (2013).
- Zheng, J., Pang, S., Labuza, T. P., He, L. Evaluation of surface-enhanced Raman scattering detection using a handheld and a bench-top Raman spectrometer: A comparative study. Talanta. 129, 79-85 (2014).
