University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Raman

Classification: Raman -> surface enhanced

Citations 15

"Flow Injection Analysis And Liquid Chromatography: Surface Enhanced Raman Spectrometry Detection By Using A Windowless Flow Cell"
Anal. Chim. Acta 1996 Volume 318, Issue 2 Pages 203-210

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L. M. Cabalín, A. Rupérez and J. J. Laserna*

Abstract: A windowless flow cell was developed for detection by surface-enhanced Raman spectrometry (SERS) in FIA and LC. The flow cell consisted of two stainless-steel tubes (0.16 mm i.d.; 1.4 mm o.d.) mounted on an Al frame so that the ends were ~e;1.6 mm apart. The liquid draining from the upper to the lower tube was supported by surface tension and formed a column (1.4 mm diameter). The mobile phase from the FIA or LC was merged with a silver hydrosol stream then propelled in to the flow cell. The Raman spectra were recorded using a focussed Ar ion laser beam (488 nm; 85 mW) as the source. The performance of the flow cell was optimized using five drugs (amiloride, amiphenazole, 2-mercaptopyridine, pemoline and triamterene) as model analytes. The maximum SERS signal was obtained with flow rates of 0.075 ml/ml and 1.5 ml/ml for the mobile phase and silver hydrosol, respectively. The reproducibility (n = 5) of the FIA-SERS system for the determination of 625 ng amiloride was 1%.
Amiloride Amiphenazole 2-Mercaptopyridine Pemoline Triamterene Flowcell Optimization

"Coupling Of Column Liquid-chromatography And Surface-enhanced Resonance Raman-spectroscopy Via A Thin-layer Chromatographic Plate"
Anal. Chim. Acta 1997 Volume 349, Issue 1-3 Pages 189-197

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G. W. Somsen*, S. K. Coulter, C. Gooijer, N. H. Velthorst and U. A. Th. Brinkman

Abstract: Surface-enhanced resonance Raman (SERR) spectroscopy was used to characterize compounds separated by column liquid chromatography (LC). Three percent of the effluent from a conventional-size LC column were immobilized on a moving thin-layer chromatography (TLC) plate using a spray-jet solvent-elimination interface. Next, colloidal silver was applied to the analyte spots and in situ SERR spectra were recorded with a multichannel micro-Raman spectrometer. Storage of the LC effluent avoids the need to use a continuous-flow of colloidal silver and, in principle allows compounds to be detected independently of LC conditions like eluent composition and flow rate. Using dyes as test compounds, the method was optimized and aspects were studied such as type of TLC plate, LC separation of the dyes, preservation of LC integrity during immobilization, and SERR analysis of the deposited compounds. With a silica TLC plate as deposition substrate, good-quality and characteristic SERR spectra were obtained for the dyes which were separated on a cyanoproyl-modified silica LC column with methanol-water containing the volatile additives ammonium acetate and triethylamine as eluent. The minimum identifiable concentration of the dyes was about 250 ng mL-1 (750 pg applied on the plate). For some strong Raman scatterers such as nile blue and pararosaniline, the major spectral peaks could be observed down to concentrations of 25 ng mL-1. 36 References
Post-column derivatization Optimization

"Quantitative Analysis By Surface-enhanced Raman Spectrometry On Silver Hydrosols In A Flow Injection System"
Talanta 1987 Volume 34, Issue 8 Pages 745-747

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J. J. Laserna, A. Berthod and J. D. Winefordner

Abstract: The application of surface-enhanced Raman scattering (SERS) in quantitative analysis is demonstrated by the determination of 4-aminobenzoic acid(I) and acridin-9-amine(II) on silver suspensions by SERS in a flow injection system. Two peristaltic pumps were used to mix 2 mM NaBH4 and 1 mM AgNO3 and pump the resulting silver suspension through the flow injection analysis system. The flow injection analysis system is described (with diagram). The sample solution contained I in aqueous 40% ethanol or II in ethanol. The calibration graph was rectilinear for 4 to 100 µg mL-1 of I, and the coefficient of variation (n = 6) was 3.2%. The system required cleaning with 40% HNO3 after 10 to 15 injections.
Aminoacridine aminobenzoic acid Suspension

"Surface Enhanced Raman Spectroscopy As A Molecular Specific Detection System In Aqueous Flow-through Systems"
Analyst 1998 Volume 123, Issue 5 Pages 1057-1060

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N. Weißenbacher, B. Lendl, J. Frank, H. D. Wanzenböck and R. Kellner

Abstract: Surface enhanced Raman scattering (SERS) is proposed as a mol. specific technique for direct measurements of organic molecules in aqueous solutions An FT-Raman spectrometer was interfaced with a flow injection manifold operated in the stopped-flow mode enabling reproducible collection of SERS spectra due to the automation of the anal. procedure. For SERS a solid state substrate placed in a newly developed flow-cell was used. Multiple measurements on one single SERS substrate were achieved by rinsing the substrate with reagents such as 3 M KCl or 0.1 M NaOH solutions prior to the next measurements to remove retained analytes from the surface of the SERS substrate. This procedure allowed for improved precision as compared with a conventional batch approach. Quant. aspects were studied by establishing a calibration curve for nicotinic acid which was used as a model analyte. A linear dependence of the recorded SERS intensities from the logarithm of the analyte concentration. was obtained throughout the whole studied concentration. range (0.001-0.1 M, correlation coefficient r2 = 0.97). The standard deviation of the method sx0 is 0.122 mM and detection limit 1.7 mM, respectively. The results demonstrate the potential of SERS spectroscopy to be used as a molecular specific detector in aqueous flow systems such as flow injection anal.
Nicotinic acid Stopped-flow Flowcell Apparatus Method comparison

"Surface-enhanced Raman Spectroscopy At A Silver Electrode As A Detector In Flow Injection Analysis"
Anal. Chem. 1988 Volume 60, Issue 18 Pages 1987-1989

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R. Ken Force

Abstract: A Ag-ring reference (diameter 5 mm) and a Ag-disc working electrode (diameter 3 mm) were sealed 1 mm apart in a Pyrex tube (o.d. 7 mm) and polished smooth. The Ag ring was anodized at 0.4 V (vs. a SCE) in 0.1 M KCl to produce a Ag - AgCl reference electrode with a potential of ~0.190 to ~0.200 V (vs. a NHE) in the 0.1 M KCl used as mobile phase and supporting electrolyte. The apparatus was applied in flow injection analysis for 50.0 mM pyridine (1 mL injections) in KCl flowing at 2 mL min-1. The potential was held at -0.6 V. Raman spectra were recorded from 990 to 1050 cm-1 in 2-cm-1 steps. A detection limit of ~250 nM was achieved. A Ag-ring reference (diameter 5 mm) and a Ag-disc working electrode (diameter 3 mm) were sealed 1 mm apart in a Pyrex tube (o.d. 7 mm) and polished smooth.

"Surface-enhanced Raman Spectroscopy At A Silver Electrode As A Detection System In Flowing Streams"
Anal. Chem. 1990 Volume 62, Issue 7 Pages 678-680

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Neil J. Pothier and R. Ken Force

Abstract: A three-electrode surface-enhanced Raman spectroscopy detector, with a Ag working electrode, Pt foil auxiliary electrode and SCE reference and a cell volume of 30 µL, was evaluated for use with HPLC and flow injection analysis. In a flowing system, the analyte is rapidly removed from the electrode surface in 10 s, and spectra was obtained in 5 s with an optical multichannel analyzer.. Under stopped-flow conditions, detection limits were 175, 233 and 211 pmol for adenine, thymine and cytosine, respectively.
Adenine Thymine Cytosine Multichannel Stopped-flow Detection limit

"Flow Injection Analysis And Real-time Detection Of RNA Bases By Surface-enhanced Raman Spectroscopy"
Anal. Chem. 1990 Volume 62, Issue 18 Pages 1958-1963

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Fan Ni, Rongsheng Sheng, and Therese M. Cotton

Abstract: Surface-enhanced Raman scattering (SERS) spectroscopy has been successfully interfaced with a flow injection analysis system to detect RNA bases in real time. Four of the major base components of RNA, uracil, cytosine, adenine, and guanine, were introduced into the flow injection system and were mixed with a Ag sol prior to SERS measurements. Several experimental parameters including pH, temperature, flow rate, and tubing materials were examined, and their impact on the SERS spectra is presented here. The feasibility of interfacing flow injection based SERS detection methods with liquid or high performance liquid chromatography for the detection of individual components in a complex mixture is also assessed.
Bases, RNA Interface pH Optimization

"Evaluation And Optimization Of Experimental Conditions For Surface-enhanced Raman Detection Of Analytes In Flow Injection Analysis"
Microchem. J. 1988 Volume 38, Issue 1 Pages 125-126

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J. J. Laserna, A. Berthod and J. D. Winefordner*

Abstract: The Raman instrumentation included a 100-mW Ar ion laser operated at 514.5 nm, a double monochromator and a cooled Hamamatsu R-928 photomultiplier tube with photon counting system as the detector. Vertically polarized light was used, with right-angle geometry for Raman sampling and a long-wave-pass glass filter to suppress Rayleigh-scattered light. Spectra were obtained by single scans. Flow streams of 1 mM AgNO3 and 2 mM NaBH4 were merged to form a silver hydrosol matrix, and 4-aminobenzoic acid(I) and acridin-9-amine were used successfully as test analytes. The detector flow-cell was a silica tube (3 mm x 0.5 mm;~0.6 µL). For maximum signal response with I, the total flow rate was 0.7 mL min-1 and the pH was adjusted with HNO3 to 3.2.
4-Aminobenzoic acid 9-Aminoacridine Detector Optimization

"New Spectroelectrochemical Cell For Flow Injection Analysis And Its Application To The Determination Of Iron(II) Down To The Femtomole Level By Surface-enhanced Resonance Raman Scattering (SERRS)"
J. Electroanal. Chem. 1994 Volume 371, Issue 1-2 Pages 37-42

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Vitor J. P. Gouveia, Ivano G. Gutz and Joel C. Rubim*

Abstract: A principal feature of the cell (diagrams presented) is the in situ renewal of the surface-enhanced Raman-active Ag substratum. Before injection of the analyte, Ag+ are introduced, and Ag is electro-deposited on a vitreous-carbon electrode; after the Raman spectrum of the adsorbed analyte has been recorded, the Ag is removed by anodic stripping. Fe(II) was determined in a 130 µL injected sample as its tris(bipyridyl) complex, which exhibits both a resonance Raman effect when excited with Ar+ laser 514.5 nm radiation and surface-enhanced Raman scattering when adsorbed on Ag. The calibration graph was sigmoidal, but usable for 10 nM-10 µM-Fe(II), and the detection limit was 1 nM, which represented detection of Fe(II) at the femtomole level.
Iron(2+) Environmental

"Continuous Surface-enhanced Raman-spectroscopy For The Detection Of Trace Organic Pollutants In Aqueous Systems"
J. Mol. Struct. 1997 Volume 410, Issue 1 Pages 539-542

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N. Weissenbacher*, B. Lendl, J. Frank, H. D. Wanzenböck, B. Mizaikoff and R. Kellner

Abstract: In Raman spectroscopy, detection limits for organic pollutants in water can be lowered by several orders of magnitude when surface enhanced techniques are applied. In this work a continuous analytical device based on flow injection analysis using SERS detection is proposed. This system was tested with model analytes such as pyridine and nicotinic acid as well as several pesticides (carbendazim, metazachlorine). (C) 1997 Elsevier Science B.V. 22 References
Pyrodine Nicotinic acid Pesticides Carbendazim Metazachlore

"Novel Detection System Of Flow Injection Analysis. 1. The Existence Of Significant Relation Between Secondary Structure Of DNA And Sensitivity In Signal Detection"
Nucleic Acids Symp. Ser. 1997 Volume 37, Issue 1 Pages 247-248

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Sawata S, Kai E, Ikebukuro K, Iida T, Honda T, Karube I.

Abstract: Polymerase Chain Reaction (PCR) products were detected quantitatively using a flow injection type sensor, based on Surface Plasmon Resonance (SPR). We used asymmetric PCR to amplify the two kinds of products; their DNA lengths are different. This novel design permitted us not only to detect PCR products with high-sensitivity, but also to develop a rapid DNA detection system for the sense of the genetic pathogen.
DNA Sensitivity

"Applications Of Surface-enhanced Raman Scattering (SERS) To Chemical Detection"
Spectroscopy 1995 Volume 10, Issue 3 Pages 20-25

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Storey, J.M.E.;Barber, T.E.;Shelton, R.D.;Wachter, E.A.;Carron, K.T.;Jiang, Y.

Abstract: lectrochemical surface-enhanced Raman spectrometry (SERS) was used to detect chlorinated hydrocarbons in ground water, in tobacco smoke and aqueous cyanide ions. Hybrid substrate SERS was used for the detection of organic compounds in liquid and gas phases, using a flow-through cell. The experimental protocols were described previously. (Appl Spectrosc., 1994, 48, 1265; Shelton et al., Ibid., 1994, 48, 1007; Wachter et al.,Ibid., 1995, 49, 193; and Barber et al., Ibid., 1994, 48, 1423). The detection limits for hydrocarbons in electrolytes were a few ppm; they were an order of magnitude higher in groundwater. No calibration data are given. The response to cyanide was linear for 10^-100 ppm. The detection limit for nicotine in smoke was 15 ppb (no calibration data given). The advantages and limitations of the methods are discussed and future research directions are outlined.
Cyanide Hydrocarbons, halo Nicotine Smoke Environmental Review

"Application Of Waveguiding In Solutions For Absorption And Fluorescence Spectrometry"
Trends Anal. Chem. 1991 Volume 10, Issue 6 Pages 184-190

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Kitao Fujiwara and Seiji Ito

Abstract: Several waveguiding techniques in solution are presented in the context of spectrometry. Although light propagation in dense media via total reflection is a commonly used technique with optical fibers, it is also possible in solutions. This is very useful for improving both sensitivity and spatial resolution, especially in absorption and fluorescence spectrometry, by elongating the optical path length and controlling the angle of incidence of light in the measurement area of a sample.
Apparatus Flowcell Waveguide cell

"Surface Enhanced Raman Spectroscopy Using Metallic Nanostructures"
Trends Anal. Chem. 1998 Volume 17, Issue 8-9 Pages 557-582

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Tuan Vo-Dinh

Abstract: This article provides an overview of the development and application of the surface-enhanced Raman scattering (SERS) techniques using metal-coated nanostructures on solid substrates, An introduction to theoretical principles of the SERS effect and the different SERS-active media is presented. The focus is on nanostructured solid substrates and their practical applications in chemical, environmental and biomedical areas. Specific examples of analytical techniques, instruments and sensors developed in the author's laboratory will be discussed to illustrate the usefulness and potential of the SERS techniques.
Environmental Biological Apparatus Instrumentation Review

"Identification Of Stimulant Drugs By Surface-enhanced Raman Spectrometry On Colloidal Silver"
Vib. Spectrosc. 1991 Volume 2, Issue 2-3 Pages 145-154

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