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Das A, Fehse S, Polack M, Panneerselvam R, Belder D. Surface-Enhanced Raman Spectroscopic Probing in Digital Microfluidics through a Microspray Hole. Anal Chem 2023; 95:1262-1272. [PMID: 36577121 DOI: 10.1021/acs.analchem.2c04053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We report a novel approach for surface-enhanced Raman spectroscopy (SERS) detection in digital microfluidics (DMF). This is made possible by a microspray hole (μSH) that uses an electrostatic spray (ESTAS) for sample transfer from inside the chip to an external SERS substrate. To realize this, a new ESTAS-compatible stationary SERS substrate was developed and characterized for sensitive and reproducible SERS measurements. In a proof-of-concept study, we successfully applied the approach to detect various analyte molecules using the DMF chip and achieved micro-molar detection limits. Moreover, this technique was exemplarily employed to study an organic reaction occurring in the DMF device, providing vibrational spectroscopic data.
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Affiliation(s)
- Anish Das
- Institute of Analytical Chemistry, Leipzig University, Linnéstraße 3, Leipzig 04103, Germany
| | - Sebastian Fehse
- Institute of Analytical Chemistry, Leipzig University, Linnéstraße 3, Leipzig 04103, Germany
| | - Matthias Polack
- Institute of Analytical Chemistry, Leipzig University, Linnéstraße 3, Leipzig 04103, Germany
| | - Rajapandiyan Panneerselvam
- Institute of Analytical Chemistry, Leipzig University, Linnéstraße 3, Leipzig 04103, Germany.,Department of Chemistry, SRM University AP, Amaravati, Andhra Pradesh 522502, India
| | - Detlev Belder
- Institute of Analytical Chemistry, Leipzig University, Linnéstraße 3, Leipzig 04103, Germany
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2
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Ali A, Nettey-Oppong EE, Effah E, Yu CY, Muhammad R, Soomro TA, Byun KM, Choi SH. Miniaturized Raman Instruments for SERS-Based Point-of-Care Testing on Respiratory Viruses. BIOSENSORS 2022; 12:bios12080590. [PMID: 36004986 PMCID: PMC9405795 DOI: 10.3390/bios12080590] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 07/24/2022] [Accepted: 07/26/2022] [Indexed: 06/12/2023]
Abstract
As surface-enhanced Raman scattering (SERS) has been used to diagnose several respiratory viruses (e.g., influenza A virus subtypes such as H1N1 and the new coronavirus SARS-CoV-2), SERS is gaining popularity as a method for diagnosing viruses at the point-of-care. Although the prior and quick diagnosis of respiratory viruses is critical in the outbreak of infectious disease, ELISA, PCR, and RT-PCR have been used to detect respiratory viruses for pandemic control that are limited for point-of-care testing. SERS provides quantitative data with high specificity and sensitivity in a real-time, label-free, and multiplex manner recognizing molecular fingerprints. Recently, the design of Raman spectroscopy system was simplified from a complicated design to a small and easily accessible form that enables point-of-care testing. We review the optical design (e.g., laser wavelength/power and detectors) of commercialized and customized handheld Raman instruments. As respiratory viruses have prominent risk on the pandemic, we review the applications of handheld Raman devices for detecting respiratory viruses. By instrumentation and commercialization advancements, the advent of the portable SERS device creates a fast, accurate, practical, and cost-effective analytical method for virus detection, and would continue to attract more attention in point-of-care testing.
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Affiliation(s)
- Ahmed Ali
- Department of Electrical Engineering, Sukkur IBA University, Sukkur 65200, Pakistan;
| | - Ezekiel Edward Nettey-Oppong
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Korea; (E.E.N.-O.); (E.E.); (C.Y.Y.); (R.M.)
| | - Elijah Effah
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Korea; (E.E.N.-O.); (E.E.); (C.Y.Y.); (R.M.)
| | - Chan Yeong Yu
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Korea; (E.E.N.-O.); (E.E.); (C.Y.Y.); (R.M.)
| | - Riaz Muhammad
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Korea; (E.E.N.-O.); (E.E.); (C.Y.Y.); (R.M.)
| | - Toufique Ahmed Soomro
- Department of Electronic Engineering, Quid-e-Awam University of Engineering, Science and Technology, Larkana 77150, Pakistan;
| | - Kyung Min Byun
- Department of Biomedical Engineering, Kyung Hee University, Yongin 17104, Korea
- Department of Electronics and Information Convergence Engineering, Kyung Hee University, Yongin 17104, Korea
| | - Seung Ho Choi
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Korea; (E.E.N.-O.); (E.E.); (C.Y.Y.); (R.M.)
- Department of Integrative Medicine, Major in Digital Healthcare, Yonsei University College of Medicine, Seoul 06229, Korea
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3
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Tanwar S, Kaur V, Kaur G, Sen T. Broadband SERS Enhancement by DNA Origami Assembled Bimetallic Nanoantennas with Label-Free Single Protein Sensing. J Phys Chem Lett 2021; 12:8141-8150. [PMID: 34410129 DOI: 10.1021/acs.jpclett.1c02272] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Engineering hotspots in surface-enhanced Raman spectroscopy (SERS) through precisely controlled assembly of plasmonic nanostructures capable of expanding intense field enhancement are highly desirable to enhance the potentiality of SERS as a label-free optical tool for single molecule detection. Inspired by DNA origami technique, we constructed plasmonic dimer nanoantennas with a tunable gap decorated with Ag-coated Au nanostars on origami. Herein, we demonstrate the single-molecule SERS enhancements of three dyes with emission in different spectral regions after incorporation of single dye molecules in between two nanostars. The enhancement factors (EFs) achieved in the range of 109-1010 for all the single dye molecules, under both resonant and nonresonant excitation conditions, would enable enhanced photostability during time-series measurement. We further successfully explored the potential of our designed nanoantennas to accommodate and detect a single thrombin protein molecule after selective placement in the wide nanogap of 10 nm. Our results suggest that such nanoantennas can serve as a broadband SERS enhancer and enable specific detection of target biological molecules with single-molecule sensitivity.
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Affiliation(s)
- Swati Tanwar
- Institute of Nano Science and Technology, Sector-81, Mohali, Punjab-140306, India
| | - Vishaldeep Kaur
- Institute of Nano Science and Technology, Sector-81, Mohali, Punjab-140306, India
| | - Gagandeep Kaur
- Institute of Nano Science and Technology, Sector-81, Mohali, Punjab-140306, India
| | - Tapasi Sen
- Institute of Nano Science and Technology, Sector-81, Mohali, Punjab-140306, India
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Voegtle MJ, Pal T, Pennathur AK, Menachekanian S, Patrow JG, Sarkar S, Cui Q, Dawlaty JM. Interfacial Polarization and Ionic Structure at the Ionic Liquid-Metal Interface Studied by Vibrational Spectroscopy and Molecular Dynamics Simulations. J Phys Chem B 2021; 125:2741-2753. [PMID: 33689335 DOI: 10.1021/acs.jpcb.0c11232] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ionic liquids (ILs) have both fundamental and practical value in interfacial science and electrochemistry. However, understanding their behavior near a surface is challenging because of strong Coulomb interactions and large and irregular ionic sizes, which affect both their structure and energetics. To understand this problem, we present a combined experimental and computational study using a vibrational probe molecule, 4-mercaptobenzonitrile, inserted at the junction between a metal and a variety of ILs. The vibrational frequency of the nitrile in the probe molecule reports on the local solvation environment and the electrostatic field at this junction. Within the ethylmethyl imidazolium (EMIM+) cation family of ILs, we varied the anions over a range of sizes and types. Complementing our surface spectroscopy, we also ran molecular dynamics simulations of these interfaces to better understand the ionic structures that produced the measured fields. The magnitude of the frequency shifts, and thereby fields, shows a general correlation with the size of anions, with larger anions corresponding to smaller fields. We find that the source of this correlation is partial intercalation of smaller anions into the probe monolayer, resulting in tighter packing of ionic layers near the surface. Larger anions reduce the overall lateral ion packing density near the surface, which reduces the net charge per unit area and explains the smaller observed fields. The insight from this work is important for developing a fundamental picture of concentrated electrolytes near interfaces and can help with designing ILs to create tailored electric fields near an electrode.
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Affiliation(s)
- Matthew J Voegtle
- Department of Chemistry, University of Southern California, Los Angeles, California 90007, United States
| | - Tanmoy Pal
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
| | - Anuj K Pennathur
- Department of Chemistry, University of Southern California, Los Angeles, California 90007, United States
| | - Sevan Menachekanian
- Department of Chemistry, University of Southern California, Los Angeles, California 90007, United States
| | - Joel G Patrow
- Department of Chemistry, University of Southern California, Los Angeles, California 90007, United States
| | - Sohini Sarkar
- Department of Chemistry, University of Southern California, Los Angeles, California 90007, United States
| | - Qiang Cui
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
| | - Jahan M Dawlaty
- Department of Chemistry, University of Southern California, Los Angeles, California 90007, United States
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Pennathur AK, Voegtle MJ, Menachekanian S, Dawlaty JM. Strong Propensity of Ionic Liquids in Their Aqueous Solutions for an Organic-Modified Metal Surface. J Phys Chem B 2020; 124:7500-7507. [PMID: 32786711 DOI: 10.1021/acs.jpcb.0c04665] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Understanding ionic structure and electrostatic environments near a surface has both fundamental and practical value. In electrochemistry, especially when room temperature ionic liquids (ILs) are involved, the complex ionic structure near the interface is expected to crucially influence reactions. Here we report evidence that even in dilute aqueous solutions of several ILs, the ions aggregate near the surface in ways that are qualitatively different from simple electrolytes. We have used a vibrational probe molecule, 4-mercaptobenzonitrile (MBN), tethered to a metal surface to monitor the behavior of the ionic layers. The characteristic nitrile vibrational frequency of this molecule has distinct values in the presence of pure water (∼2232 cm-1) and pure IL (for example, ∼2226 cm-1 for ethylmethylimidazolium tetrafluoroborate, [EMIM][BF4]). This difference reflects the local electrostatic field and the hydrogen-bonding variations between these two limiting cases. We tracked this frequency shift as a function of IL concentration in water all the way from pure water to pure IL. We report two important findings. First, only one nitrile peak is observed for the entire concentration range, indicating that at least on the length scale of the probe molecule water and ILs do not phase separate within the interface, and no heterogeneously distinct electrostatic environments are formed. Second, and more importantly, we find that even up to a significant mole fraction of bulk water (x ∼ 0.95), the nitrile frequency does not change from that indicative of a pure IL for [EMIM][BF4], indicating preferential aggregation of the ions near the surface. Because this behavior is very similar to surfactants, we chose an imidazolium cation with a longer side chain which resulted in behavior expected from a surfactant, with a preferential layer of the ions on the surface even in dilute water solutions (x ∼ 0.995). This observation indicates that even those ILs that are not nominally categorized as surfactants have a strong tendency to aggregate at the surface. Because ILs serve as electrolytes in a range of electrochemical reactions, including those requiring water, our results are likely useful for mechanistic understanding and tuning of such reactions.
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Affiliation(s)
- Anuj K Pennathur
- Department of Chemistry, University of Southern California, Los Angeles, California 90007, United States
| | - Matthew J Voegtle
- Department of Chemistry, University of Southern California, Los Angeles, California 90007, United States
| | - Sevan Menachekanian
- Department of Chemistry, University of Southern California, Los Angeles, California 90007, United States
| | - Jahan M Dawlaty
- Department of Chemistry, University of Southern California, Los Angeles, California 90007, United States
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Sarkar S, Maitra A, Banerjee S, Thoi VS, Dawlaty JM. Electric Fields at Metal-Surfactant Interfaces: A Combined Vibrational Spectroscopy and Capacitance Study. J Phys Chem B 2020; 124:1311-1321. [PMID: 31985221 DOI: 10.1021/acs.jpcb.0c00560] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Surfactants modulate interfacial processes. In electrochemical CO2 reduction, cationic surfactants promote carbon product formation and suppress hydrogen evolution. The interfacial field produced by the surfactants affects the energetics of electrochemical intermediates, mandating their detailed understanding. We have used two complementary tools-vibrational Stark shift spectroscopy which probes interfacial fields at molecular length scales and electrochemical impedance spectroscopy (EIS) which probes the entire double layer-to study the electric fields at metal-surfactant interfaces. Using a nitrile as a probe, we found that at open-circuit potentials, cationic surfactants produce larger effective interfacial fields (∼-1.25 V/nm) when compared to anionic surfactants (∼0.4 V/nm). At a high bulk surfactant concentration, the surface field reaches a terminal value, suggesting the formation of a full layer, which is also supported by EIS. We propose an electrostatic model that explains these observations. Our results help in designing tailored surfactants for influencing electrochemical reactions via the interfacial field effect.
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Affiliation(s)
- Sohini Sarkar
- Department of Chemistry , University of Southern California , Los Angeles , California 90007 , United States
| | - Anwesha Maitra
- Department of Chemistry , University of Southern California , Los Angeles , California 90007 , United States
| | - Soumyodip Banerjee
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - V Sara Thoi
- Department of Chemistry , Johns Hopkins University , Baltimore , Maryland 21218 , United States
| | - Jahan M Dawlaty
- Department of Chemistry , University of Southern California , Los Angeles , California 90007 , United States
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Li B, Wang T, Su Q, Wu X, Dong P. Fabrication of Au Nanorods by the Oblique Angle Deposition Process for Trace Detection of Methamphetamine with Surface-Enhanced Raman Scattering. SENSORS 2019; 19:s19173742. [PMID: 31470612 PMCID: PMC6749386 DOI: 10.3390/s19173742] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 08/14/2019] [Accepted: 08/20/2019] [Indexed: 01/12/2023]
Abstract
Oblique angle deposition (OAD) is a simple, low cost, effective, and maskless nanofabrication process. It can offer a reliable method for the mass fabrication of uniform metal nanorods which can be used as the surface-enhanced Raman scattering (SERS) substrate with an excellent enhancing performance. Up to now, Ag nanorods SERS substrates have been extensively studied. However, Ag is chemically active and easy to oxidize under atmospheric conditions. Comparatively, Au is chemically stable and has better biocompatibility than Ag. In this paper, we in detail, studied the electromechanical (EM) field distribution simulation, fabrication, and application of Au nanorods (AuNRs) on trace detection of methamphetamine. According to the finite-difference time-domain (FDTD) calculation results, the maximum EM intensity can be obtained with the length of AuNRs to be 800 nm and the tilting angle of AuNRs to be 71° respectively. The aligned Au nanorod array substrate was fabricated by the OAD process. The two key process parameters, deposition angle, and deposition rate were optimized by experiments, which were 86° and 2 Å/s, respectively. Using 1,2-bis (4-pyridyl) ethylene (BPE) as the probe molecule, the limit of detection (LOD) was characterized to be 10−11 M. The AuNRs were also used to detect methamphetamine. The LOD can be down to M (i.e., 14.92 pg/ml), which meet the requirements of the on-site rapid detection of the methamphetamine in human urine (500 ng/ml).
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Affiliation(s)
- Baini Li
- College of Intelligence Science and Technology, National University of Defense Technology, Changsha 410073, China
| | - Tianran Wang
- College of Intelligence Science and Technology, National University of Defense Technology, Changsha 410073, China
| | - Qingqing Su
- College of Intelligence Science and Technology, National University of Defense Technology, Changsha 410073, China
| | - Xuezhong Wu
- College of Intelligence Science and Technology, National University of Defense Technology, Changsha 410073, China
| | - Peitao Dong
- College of Intelligence Science and Technology, National University of Defense Technology, Changsha 410073, China.
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8
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Wang J, Yi G. Flexible and Superhydrophobic Silver Nanoparticles Decorated Aligned Silver Nanowires Films as Surface-Enhanced Raman Scattering Substrates. NANOSCALE RESEARCH LETTERS 2019; 14:292. [PMID: 31440839 PMCID: PMC6706522 DOI: 10.1186/s11671-019-3117-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 08/06/2019] [Indexed: 05/27/2023]
Abstract
Flexible and superhydrophobic silver nanoparticles decorated aligned silver nanowires (AgNWs@AgNPs) films were employed as efficient surface-enhanced Raman scattering (SERS) substrates to investigate the SERS properties of the Rhodamine B (RB). Aligned silver nanowires were fabricated via interface self-assembly technique and incorporated into shape memory polyurethane (SMPU) by hot-press method, which not only endow the composites with ordered array characteristics but also flexibility due to the presence of polymer. After an electrochemical deposition combined with a galvanic reaction, AgNWs@AgNPs was obtained. At last, the substrate was functioned with perfluorodecanethiol (PFDT), and the target flexible and superhydrophobic silver nanoparticles decorated aligned silver nanowires substrate was obtained. The substrate confines water droplet in a small area, and the analytes were enriched owing to the concentrating effect. The SERS assay using the as-synthesized flexible and superhydrophobic silver films as substrates can detect Rhodamine B as low as10-10 M. The mechanism is thought to relate to the formation of robust superhydrophobic film, which is based on micro- and nanoscaled hierarchical structure provided by the AgNWs@AgNPs layer, strong adhesion between the SMPU film and the AgNWs@AgNPs layer, and the low surface energy molecule adsorption on the silver surface. The combined superhydrophobic and flexible properties endow the SERS substrate with improved detection limit for practical SERS applications.
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Affiliation(s)
- Jianchao Wang
- The Collaborative Innovation Center of Manganese-Zinc-Vanadium Industrial Technology, National Demonstration Center for Experimental Chemistry Education, Hunan Engineering Laboratory for Analyse and Drugs Development of Ethnomedicine in Wuling Mountains, Jishou University, Jishou, 416000, China.
| | - Guobin Yi
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, Guangdong, China
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Höhn EM, Panneerselvam R, Das A, Belder D. Raman Spectroscopic Detection in Continuous Microflow Using a Chip-Integrated Silver Electrode as an Electrically Regenerable Surface-Enhanced Raman Spectroscopy Substrate. Anal Chem 2019; 91:9844-9851. [DOI: 10.1021/acs.analchem.9b01514] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Eva-Maria Höhn
- Institut für Analytische Chemie, Universität Leipzig, Johannisallee 29, Leipzig 04103, Germany
| | | | - Anish Das
- Institut für Analytische Chemie, Universität Leipzig, Johannisallee 29, Leipzig 04103, Germany
| | - Detlev Belder
- Institut für Analytische Chemie, Universität Leipzig, Johannisallee 29, Leipzig 04103, Germany
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Surface-Enhanced Raman Scattering Detection of Fipronil Pesticide Adsorbed on Silver Nanoparticles. SENSORS 2019; 19:s19061355. [PMID: 30889914 PMCID: PMC6471083 DOI: 10.3390/s19061355] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 02/26/2019] [Accepted: 03/05/2019] [Indexed: 02/05/2023]
Abstract
This work presents a surface-enhanced Raman scattering (SERS) and density functional theory (DFT) study of a fipronil adsorbed on colloidal silver nanoparticles (AgNPs). A standard curve was established to quantify fipronil within a range of 0.0001⁻0.1 ppm (r² ≥ 0.985), relying on the unique fipronil Raman shift at ~2236 cm-1 adsorbed on AgNPs. DFT calculations suggest that the nitrile moiety (C≡N) binding should be slightly more favorable, by 1.92 kcal/mol, than those of the nitrogen atom of the pyrazole in fipronil and Ag₆ atom clusters. The characteristic peaks of the SERS spectrum were identified, and both the calculated vibrational wavenumbers and the Raman intensity pattern were considered. The vibrational spectra of fipronil were obtained from the potential energy distribution (PED) analysis and selective Raman band enhancement.
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Tong Q, Wang W, Fan Y, Dong L. Recent progressive preparations and applications of silver-based SERS substrates. Trends Analyt Chem 2018. [DOI: 10.1016/j.trac.2018.06.018] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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12
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Martín-Yerga D, Pérez-Junquera A, González-García MB, Perales-Rondon JV, Heras A, Colina A, Hernández-Santos D, Fanjul-Bolado P. Quantitative Raman spectroelectrochemistry using silver screen-printed electrodes. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2018.01.060] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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13
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Kearns H, Ali F, Bedics MA, Shand NC, Faulds K, Detty MR, Graham D. Sensitive SERS nanotags for use with a hand-held 1064 nm Raman spectrometer. ROYAL SOCIETY OPEN SCIENCE 2017; 4:170422. [PMID: 28791168 PMCID: PMC5541563 DOI: 10.1098/rsos.170422] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 06/23/2017] [Indexed: 06/07/2023]
Abstract
This is the first report of the use of a hand-held 1064 nm Raman spectrometer combined with red-shifted surface-enhanced Raman scattering (SERS) nanotags to provide an unprecedented performance in the short-wave infrared (SWIR) region. A library consisting of 17 chalcogenopyrylium nanotags produce extraordinary SERS responses with femtomolar detection limits being obtained using the portable instrument. This is well beyond previous SERS detection limits at this far red-shifted wavelength and opens up new options for SERS sensors in the SWIR region of the electromagnetic spectrum (between 950 and 1700 nm).
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Affiliation(s)
- Hayleigh Kearns
- Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, 99 George Street, Glasgow G1 1RD, UK
| | - Fatima Ali
- Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, 99 George Street, Glasgow G1 1RD, UK
| | - Matthew A. Bedics
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | | | - Karen Faulds
- Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, 99 George Street, Glasgow G1 1RD, UK
| | - Michael R. Detty
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA
| | - Duncan Graham
- Department of Pure and Applied Chemistry, Technology and Innovation Centre, University of Strathclyde, 99 George Street, Glasgow G1 1RD, UK
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