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Fermor-Worth IM, Chimerel C. Broadband cavity enhanced UV-VIS absorption spectroscopy for picolitre liquid samples. Analyst 2023; 148:1797-1804. [PMID: 36920121 PMCID: PMC10089060 DOI: 10.1039/d3an00143a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
Absorption spectroscopy is a widely used analytical technique due to its label-free nature, however its application to small liquid samples is hampered by the associated short absorption pathlengths, which limit sensitivity. A novel concept for the development of an ultrasensitive broadband absorption spectrometer optimised for thin liquid films is presented here. To enhance sensitivity of the absorbance measurements an optical cavity is implemented on a fibre-based absorption spectrometer (CEASpec). Light is circulated multiple times through the sample of interest to increase sensitivity. The bandwidth of the instrument is chosen by the choice of the dielectric mirrors forming the optical cavity spectra and, in this implementation, has been set to be 200 nm wide (250-450 nm). The sensing volume of the spectroscope is prescribed by the choice of optical fibres employed to deliver light to the sample, and in this implementation fibres of 400 μm in diameter were employed, giving a sensing volume of 630 picolitres for a thin film of 5 μm in thickness. Amphotericin B, a broad light absorber in the 280-450 nm region of the spectrum, was used here to prove the capabilities of the proposed cavity enhanced absorption spectroscope. Cavity enhancement factors, the equivalent pathlength increase over classical absorption spectroscopy, in the range of 200× have been achieved across a broad wavelength range.
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Affiliation(s)
- Imogen M Fermor-Worth
- Living Systems Institute, Faculty of Health and Life Sciences, University of Exeter, Stocker Road, Exeter, Devon, EX4 4QJ, UK.
| | - Catalin Chimerel
- Living Systems Institute, Faculty of Health and Life Sciences, University of Exeter, Stocker Road, Exeter, Devon, EX4 4QJ, UK. .,Automation Department, Faculty of Electrical Engineering and Computer Science, Transilvania University of Brasov, 500036 Brasov, Romania
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2
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Sanders SE, Willis OR, Nahler NH, Wrede E. Absolute fluorescence and absorption measurements over a dynamic range of 10 6 with cavity-enhanced laser-induced fluorescence. J Chem Phys 2018; 149:014201. [PMID: 29981537 DOI: 10.1063/1.5031842] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a novel spectroscopic technique that exhibits high sensitivity and a large dynamic range for the measurement of absolute absorption coefficients. We perform a simultaneous and correlated laser-induced fluorescence and cavity ring-down measurement of the same sample in a single pulsed laser beam. The combined measurement offers a large dynamic range and a lower limit of detection than either technique on its own. The methodology, dubbed cavity-enhanced laser-induced fluorescence, is developed and rigorously tested against the electronic spectroscopy of 1,4-bis(phenylethynyl)benzene in a molecular beam and density measurements in a cell. We outline how the method can be used to determine absolute quantities, such as sample densities, absorption cross sections, and fluorescence quantum yields, particularly in spatially confined samples.
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Affiliation(s)
- Scott E Sanders
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Oliver R Willis
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - N Hendrik Nahler
- School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Eckart Wrede
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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3
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Rushworth CM, Jones G, Fischlechner M, Walton E, Morgan H. On-chip cavity-enhanced absorption spectroscopy using a white light-emitting diode and polymer mirrors. LAB ON A CHIP 2015; 15:711-7. [PMID: 25494304 DOI: 10.1039/c4lc01264j] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We have developed a disposable microfluidic chip with integrated cavity mirrors comprised of two pieces of 3M Vikuiti™ enhanced specular reflector II (ESRII) film, for performing cavity-enhanced absorption spectroscopy with a white light-emitting diode (LED). Compared to measurements made with a chip without cavity mirrors, the absorption path length is enhanced by a maximum factor of 28 at 544 nm, and the sensitivity is enhanced by approximately 5 times, enabling micromolar range detection limits to be achieved in an optical path length of only 50 μm.
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Affiliation(s)
- Cathy M Rushworth
- School of Electronics and Computer Science, University of Southampton, Highfield Campus, Southampton, SO17 1BJ, UK.
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4
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Avino S, Richmond C, Giorgini A, Malara P, Zullo R, De Natale P, Gagliardi G. High-sensitivity ring-down evanescent-wave sensing in fiber resonators. OPTICS LETTERS 2014; 39:5725-5728. [PMID: 25360969 DOI: 10.1364/ol.39.005725] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report on optical-fiber cavity ring-down spectroscopy (CRDS) in the liquid phase using a laser emitting at telecommunication wavelengths. A fiber-ring cavity, comprising a short evanescent-wave coupler for radiation-matter interaction, is used as a sensor while its resonance modes are frequency locked to the laser. Exploiting the intrinsic sensitivity and noise immunity of the CRDS technique, we show that liquid absorption can be detected down to a level that is nearly a factor of 20 above the shot noise limit. We provide a thorough comparison between the experimental results and various noise contributions and address different expressions that can be used to calculate the shot noise equivalent absorbance. As a proof of principle, polyamine detection in aqueous solutions is carried out demonstrating a minimum detectable absorbance of 1.8×10(-7) Hz(-1/2), which, to our knowledge, is the best sensitivity limit reported to date for evanescent-wave sensors.
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5
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Ye F, Zhang Y, Qi B, Qian L. Frequency-shifted interferometry--a versatile fiber-optic sensing technique. SENSORS 2014; 14:10977-1000. [PMID: 24955943 PMCID: PMC4118412 DOI: 10.3390/s140610977] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 05/24/2014] [Accepted: 06/16/2014] [Indexed: 11/30/2022]
Abstract
Fiber-optic sensing is a field that is developing at a fast pace. Novel fiber-optic sensor designs and sensing principles constantly open doors for new opportunities. In this paper, we review a fiber-optic sensing technique developed in our research group called frequency-shifted interferometry (FSI). This technique uses a continuous-wave light source, an optical frequency shifter, and a slow detector. We discuss the operation principles of several FSI implementations and show their applications in fiber length and dispersion measurement, locating weak reflections along a fiber link, fiber-optic sensor multiplexing, and high-sensitivity cavity ring-down measurement. Detailed analysis of FSI system parameters is also presented.
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Affiliation(s)
- Fei Ye
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada.
| | - Yiwei Zhang
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada.
| | - Bing Qi
- Quantum Information Science Group, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37830, USA.
| | - Li Qian
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King's College Road, Toronto, Ontario M5S 3G4, Canada.
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6
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Woods DA, Bain CD. Total internal reflection spectroscopy for studying soft matter. SOFT MATTER 2014; 10:1071-1096. [PMID: 24651911 DOI: 10.1039/c3sm52817k] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Total internal reflection (TIR) spectroscopy is a widely used technique to study soft matter at interfaces. This tutorial review aims to provide researchers with an overview of the principles, experimental design and applications of TIR spectroscopy to enable them to understand how this class of techniques might be used in their research. It also highlights limitations and pitfalls of TIR techniques, which will assist readers in critically analysing the literature. Techniques covered include attenuated total reflection infrared spectroscopy (ATR-IR), TIR fluorescence, TIR Raman scattering and cavity-enhanced techniques. Other related techniques are briefly described.
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Affiliation(s)
- David A Woods
- Department of Chemistry, Durham University, South Road, Durham, UKDH1 3LE.
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7
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Bescherer K, Barnes JA, Loock HP. Absorption Measurements in Liquid Core Waveguides Using Cavity Ring-Down Spectroscopy. Anal Chem 2013; 85:4328-34. [DOI: 10.1021/ac4007073] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Klaus Bescherer
- Department of Chemistry, Queen’s University, Kingston, ON, K7L 3N6, Canada
| | - Jack A. Barnes
- Department of Chemistry, Queen’s University, Kingston, ON, K7L 3N6, Canada
| | - Hans-Peter Loock
- Department of Chemistry, Queen’s University, Kingston, ON, K7L 3N6, Canada
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8
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Stamataki K, Papadakis V, Everest MA, Tzortzakis S, Loppinet B, Peter Rakitzis T. Monitoring adsorption and sedimentation using evanescent-wave cavity ringdown ellipsometry. APPLIED OPTICS 2013; 52:1086-1093. [PMID: 23400071 DOI: 10.1364/ao.52.001086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 12/23/2012] [Indexed: 06/01/2023]
Abstract
We monitor the adsorption of Rhodamine 800, and the sedimentation of a polytetrafluoroethylene (PTFE) suspension at the surface of a fused-silica prism, by measuring both the absorption and s-p phase shift Δ of a 740 nm probe laser beam, using evanescent-wave cavity ringdown ellipsometry (EW-CRDE). The two systems demonstrate the complementary strengths of EW-CRDE, as the progress of adsorption of the Rhodamine 800 dye can only be observed sensitively via the measurement of absorption, whereas the progress of sedimentation of PTFE can only be observed sensitively via the measurement of Δ. We show that EW-CRDE provides a sensitive method for the measurement of Δ and demonstrates precision in Δ of about 10(-4) deg.
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Affiliation(s)
- Katerina Stamataki
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Heraklion-Crete 71110, Greece
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9
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Gupta R, Goddard NJ. A novel leaky waveguide grating (LWG) device for evanescent wave broadband absorption spectroscopy in microfluidic flow cells. Analyst 2013; 138:1803-11. [DOI: 10.1039/c3an36714b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Rushworth CM, Davies J, Cabral JT, Dolan PR, Smith JM, Vallance C. Cavity-enhanced optical methods for online microfluidic analysis. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.10.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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11
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O'Connell MA, de Cuendias A, Gayet F, Shirley IM, Mackenzie SR, Haddleton DM, Unwin PR. Evanescent wave cavity ring-down spectroscopy (EW-CRDS) as a probe of macromolecule adsorption kinetics at functionalized interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:6902-6910. [PMID: 22489550 DOI: 10.1021/la3006053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Evanescent wave cavity ring-down spectroscopy (EW-CRDS) has been employed to study the interfacial adsorption kinetics of coumarin-tagged macromolecules onto a range of functionalized planar surfaces. Such studies are valuable in designing polymers for complex systems where the degree of interaction between the polymer and surface needs to be tailored. Three tagged synthetic polymers with different functionalities are examined: poly(acrylic acid) (PAA), poly(3-sulfopropyl methacrylate, potassium salt) (PSPMA), and a mannose-modified glycopolymer. Adsorption transients at the silica/water interface are found to be characteristic for each polymer, and kinetics are deduced from the initial rates. The chemistry of the adsorption interfaces has been varied by, first, manipulation of silica surface chemistry via the bulk pH, followed by surfaces modified by poly(L-glutamic acid) (PGA) and cellulose, giving five chemically different surfaces. Complementary atomic force microscopy (AFM) imaging has been used for additional surface characterization of adsorbed layers and functionalized interfaces to allow adsorption rates to be interpreted more fully. Adsorption rates for PSPMA and the glycopolymer are seen to be highly surface sensitive, with significantly higher rates on cellulose-modified surfaces, whereas PAA shows a much smaller rate dependence on the nature of the adsorption surface.
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12
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Powell HV, O’Connell MA, Zhang M, Mackenzie SR, Unwin PR. Evanescent Wave Cavity Ringdown Spectroscopy: A Platform for the Study of Supported Lipid Bilayers. Anal Chem 2012; 84:2585-91. [DOI: 10.1021/ac203493p] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Hayley V. Powell
- Department
of Chemistry, University of Warwick, Coventry
CV4 7AL, United Kingdom
| | - Michael A. O’Connell
- Department
of Chemistry, University of Warwick, Coventry
CV4 7AL, United Kingdom
| | - Meiqin Zhang
- Department
of Chemistry, University of Warwick, Coventry
CV4 7AL, United Kingdom
| | - Stuart R. Mackenzie
- Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, Oxford OX1 3QZ,
United Kingdom
| | - Patrick R. Unwin
- Department
of Chemistry, University of Warwick, Coventry
CV4 7AL, United Kingdom
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13
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James D, Oag B, Rushworth CM, Lee JWL, Davies J, Cabral JT, Vallance C. High-sensitivity online detection for microfluidics via cavity ringdown spectroscopy. RSC Adv 2012. [DOI: 10.1039/c2ra20349a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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14
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Darby SB, Smith PD, Venables DS. Cavity-enhanced absorption using an atomic line source: application to deep-UV measurements. Analyst 2012; 137:2318-21. [DOI: 10.1039/c2an35149h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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16
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Rushworth CM, James D, Lee JWL, Vallance C. Top Notch Design for Fiber-Loop Cavity Ring-Down Spectroscopy. Anal Chem 2011; 83:8492-500. [DOI: 10.1021/ac201775f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Cathy M. Rushworth
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, U.K
| | - Dean James
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, U.K
| | - Jason W. L. Lee
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, U.K
| | - Claire Vallance
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, Oxford, OX1 3TA, U.K
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17
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18
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Everest MA, Papadakis VM, Stamataki K, Tzortzakis S, Loppinet B, Rakitzis TP. Evanescent-Wave Cavity Ring-Down Ellipsometry. J Phys Chem Lett 2011; 2:1324-1327. [PMID: 26295429 DOI: 10.1021/jz200515d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We introduce the new technique of evanescent-wave cavity ring-down ellipsometry (EW-CRDE), used for the measurement of ellipsometric angles of samples at a solid-gas or solid-liquid interface, and achieve phase-shift measurements with precision of ∼0.01°. We demonstrate the technique by measuring the time-dependent refractive index of methanol-water mixtures and thin films at the liquid/fused-silica interface, showing that the monitoring of monolayers on microsecond time scales using EW-CRDE should be achievable.
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Affiliation(s)
- Michael A Everest
- †Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion-Crete, Greece
- ‡Department of Chemistry, George Fox University, Newberg, Oregon 97132, United States
| | - Vassilis M Papadakis
- †Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion-Crete, Greece
| | - Katerina Stamataki
- †Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion-Crete, Greece
| | - Stelios Tzortzakis
- †Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion-Crete, Greece
| | - Benoit Loppinet
- †Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion-Crete, Greece
| | - T Peter Rakitzis
- †Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion-Crete, Greece
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19
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Recent developments in handheld and portable optosensing—A review. Anal Chim Acta 2011; 696:27-46. [DOI: 10.1016/j.aca.2011.04.005] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 04/08/2011] [Accepted: 04/10/2011] [Indexed: 12/12/2022]
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20
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Gai H, Li Y, Yeung ES. Optical Detection Systems on Microfluidic Chips. MICROFLUIDICS 2011; 304:171-201. [DOI: 10.1007/128_2011_144] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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21
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Powell HV, Schnippering M, Cheung M, Macpherson JV, Mackenzie SR, Stavros VG, Unwin PR. Probing Redox Reactions of Immobilized Cytochrome c Using Evanescent Wave Cavity Ring-Down Spectroscopy in a Thin-Layer Electrochemical Cell. Chemphyschem 2010; 11:2985-91. [DOI: 10.1002/cphc.201000213] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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22
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Loock HP, Barnes JA, Gagliardi G, Li R, Oleschuk RD, Wächter H. Absorption detection using optical waveguide cavities. CAN J CHEM 2010. [DOI: 10.1139/v10-006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Cavity ring-down spectroscopy is a spectroscopic method that uses a high quality optical cavity to amplify the optical loss due to the light absorption by a sample. In this presentation we highlight two applications of phase-shift cavity ring-down spectroscopy that are suited for absorption measurements in the condensed phase and make use of waveguide cavities. In the first application, a fiber loop is used as an optical cavity and the sample is introduced in a gap in the loop to allow absorption measurements of nanoliters of solution at the micromolar level. A second application involves silica microspheres as high finesse cavities. Information on the refractive index and absorption of a thin film of ethylene diamine on the surface of the microresonator is obtained simultaneously by the measurements of the wavelength shift of the cavity mode spectrum and the change in optical decay time, respectively.
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Affiliation(s)
- Hans-Peter Loock
- Department of Chemistry, Queen’s University, Kingston, ON K7L 3N6, Canada
- Consiglio Nazionale Delle Ricerche-Istituto Nazionale Di Ottica (INO), Via Campi Flegrei 34, Pozzuoli, Naples 80078, Italy
| | - Jack A. Barnes
- Department of Chemistry, Queen’s University, Kingston, ON K7L 3N6, Canada
- Consiglio Nazionale Delle Ricerche-Istituto Nazionale Di Ottica (INO), Via Campi Flegrei 34, Pozzuoli, Naples 80078, Italy
| | - Gianluca Gagliardi
- Department of Chemistry, Queen’s University, Kingston, ON K7L 3N6, Canada
- Consiglio Nazionale Delle Ricerche-Istituto Nazionale Di Ottica (INO), Via Campi Flegrei 34, Pozzuoli, Naples 80078, Italy
| | - Runkai Li
- Department of Chemistry, Queen’s University, Kingston, ON K7L 3N6, Canada
- Consiglio Nazionale Delle Ricerche-Istituto Nazionale Di Ottica (INO), Via Campi Flegrei 34, Pozzuoli, Naples 80078, Italy
| | - Richard D. Oleschuk
- Department of Chemistry, Queen’s University, Kingston, ON K7L 3N6, Canada
- Consiglio Nazionale Delle Ricerche-Istituto Nazionale Di Ottica (INO), Via Campi Flegrei 34, Pozzuoli, Naples 80078, Italy
| | - Helen Wächter
- Department of Chemistry, Queen’s University, Kingston, ON K7L 3N6, Canada
- Consiglio Nazionale Delle Ricerche-Istituto Nazionale Di Ottica (INO), Via Campi Flegrei 34, Pozzuoli, Naples 80078, Italy
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Neil SR, Maeda K, Henbest KB, Goez M, Hemmens R, Timmel CR, Mackenzie SR. Cavity enhanced detection methods for probing the dynamics of spin correlated radical pairs in solution. Mol Phys 2010. [DOI: 10.1080/00268971003614368] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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24
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Pan JZ, Yao B, Fang Q. Hand-held Photometer Based on Liquid-Core Waveguide Absorption Detection for Nanoliter-scale Samples. Anal Chem 2010; 82:3394-8. [DOI: 10.1021/ac100257z] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jian-Zhang Pan
- Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
| | - Bo Yao
- Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
| | - Qun Fang
- Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
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25
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Zhang M, Powell HV, Mackenzie SR, Unwin PR. Kinetics of porphyrin adsorption and DNA-assisted desorption at the silica-water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:4004-4012. [PMID: 20104901 DOI: 10.1021/la903438p] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Evanescent wave cavity ring-down spectroscopy (EW-CRDS) has been used to study in situ the kinetics of the adsorption of 5,10,15,20-tetrakis(4-N-methylpyridiniumyl)porphyrin (TMPyP) from pH 7.4 phosphate buffer solution (PBS) to the silica-water interface and the interaction of calf thymus DNA (CT-DNA) with the resulting TMPyP-functionalized surface. TMPyP was delivered to the silica surface using an impinging jet technique to allow relatively fast surface kinetics to be accessed. Adsorption was first-order in TMPyP, and the initial adsorption rate constant at the bare surface was found to be k = (4.1 +/- 0.6) x 10(-2) cm s(-1). A deceleration in the adsorption kinetics was observed at longer times that could be described semiquantitatively using an Elovich-type kinetic expression. The limiting value of the absorbance corresponded approximately to monolayer coverage (6.2 x 10(13) molecules cm(-2)). Exposure of the TMPyP-modified silica surface to CT-DNA, achieved by flowing CT-DNA solution over the functionalized surface, resulted in efficient desorption of the TMPyP. The desorption process was driven by the interaction of TMPyP with CT-DNA, which UV-vis spectroscopy indicated involved intercalative binding. The desorption kinetics were also simulated using complementary finite element modeling of convection-diffusion coupled to a surface process.
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Affiliation(s)
- Meiqin Zhang
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
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26
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Chemical sensing using fiber cavity ring-down spectroscopy. SENSORS 2010; 10:1716-42. [PMID: 22294895 PMCID: PMC3264447 DOI: 10.3390/s100301716] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 01/23/2010] [Accepted: 02/06/2010] [Indexed: 11/17/2022]
Abstract
Waveguide-based cavity ring-down spectroscopy (CRD) can be used for quantitative measurements of chemical concentrations in small amounts of liquid, in gases or in films. The change in ring-down time can be correlated to analyte concentration when using fiber optic sensing elements that change their attenuation in dependence of either sample absorption or refractive index. Two types of fiber cavities, i.e., fiber loops and fiber strands containing reflective elements, are distinguished. Both types of cavities were coupled to a variety of chemical sensor elements, which are discussed and compared.
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Egashira K, Terasaki A, Kondow T. Photon-trap spectroscopy applied to molecules adsorbed on a solid surface: probing with a standing wave versus a propagating wave. APPLIED OPTICS 2010; 49:1151-1157. [PMID: 20197812 DOI: 10.1364/ao.49.001151] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We apply photon-trap spectroscopy, a generalized scheme of cavity ringdown spectroscopy, to infrared spectroscopy of molecular adsorbates on a solid substrate. The storage lifetime of light in a high-finesse Fabry-Perot cavity provides a high absorbance sensitivity for the substrate sample, which is placed exactly normal to the light beam in the cavity to minimize optical losses. Infrared spectra of the C-H stretching vibration of alkylsiloxane monolayer films on a silicon substrate are measured in three ways, namely by employing pulsed and continuous-wave lasers as well as by conventional Fourier transform infrared spectroscopy. The magnitude of optical absorption is shown to vary by the character of the interacting light used in the measurement, i.e., a standing wave versus a propagating wave.
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Affiliation(s)
- Kazuhiro Egashira
- East Tokyo Laboratory, Genesis Research Institute, Inc., 717-86 Futamata, Ichikawa, Chiba 272-0001, Japan
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Haselberg R, van der Sneppen L, Ariese F, Ubachs W, Gooijer C, de Jong GJ, Somsen GW. Effectiveness of charged noncovalent polymer coatings against protein adsorption to silica surfaces studied by evanescent-wave cavity ring-down spectroscopy and capillary electrophoresis. Anal Chem 2010; 81:10172-8. [PMID: 19921852 DOI: 10.1021/ac902128n] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Protein adsorption to silica surfaces is a notorious problem in analytical separations. Evanescent-wave cavity ring-down spectroscopy (EW-CRDS) and capillary electrophoresis (CE) were employed to investigate the capability of positively charged polymer coatings to minimize the adsorption of basic proteins. Adsorption of cytochrome c (cyt c) to silica coated with a single layer of polybrene (PB), or a triple layer of PB, dextran sulfate (DS), and PB, was studied and compared to bare silica. Direct analysis of silica surfaces by EW-CRDS revealed that both coatings effectively reduce irreversible protein adsorption. Significant adsorption was observed only for protein concentrations above 400 microM, whereas the PB-DS-PB coating was shown to be most effective and stable. CE analyses of cyt c were performed with and without the respective coatings applied to the fused-silica capillary wall. Monitoring of the electroosmotic flow and protein peak areas indicated a strong reduction of irreversible protein adsorption by the positively charged coatings. Determination of the electrophoretic mobility and peak width of cyt c revealed reversible protein adsorption to the PB coating. It is concluded that the combination of results from EW-CRDS and CE provides highly useful information on the adsorptive characteristics of bare and coated silica surfaces toward basic proteins.
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Affiliation(s)
- Rob Haselberg
- Department of Biomedical Analysis, Utrecht University, P.O. Box 80082, 3508 TB Utrecht, The Netherlands.
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Fiddler MN, Begashaw I, Mickens MA, Collingwood MS, Assefa Z, Bililign S. Laser spectroscopy for atmospheric and environmental sensing. SENSORS 2009; 9:10447-512. [PMID: 22303184 PMCID: PMC3267232 DOI: 10.3390/s91210447] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Accepted: 12/02/2009] [Indexed: 12/12/2022]
Abstract
Lasers and laser spectroscopic techniques have been extensively used in several applications since their advent, and the subject has been reviewed extensively in the last several decades. This review is focused on three areas of laser spectroscopic applications in atmospheric and environmental sensing; namely laser-induced fluorescence (LIF), cavity ring-down spectroscopy (CRDS), and photoluminescence (PL) techniques used in the detection of solids, liquids, aerosols, trace gases, and volatile organic compounds (VOCs).
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Affiliation(s)
- Marc N. Fiddler
- NOAA-ISET Center, North Carolina A&T State University, 1601 E Market Street Greensboro, NC 27411, USA; E-Mail:
| | - Israel Begashaw
- Department of Physics, North Carolina A&T State University, Greensboro, 1601 E Market Street, Marteena Hall, Greensboro, NC 27411, USA; E-Mail:
| | - Matthew A. Mickens
- Department of Chemistry, North Carolina A&T State University, 1601 E Market Street, New Science Building, Greensboro, NC 27411, USA; E-Mail:
- Energy & Environmental Systems Program, North Carolina A&T State University, 1601 E Market Street, Greensboro, NC 27411, USA; E-Mail:
| | - Michael S. Collingwood
- Energy & Environmental Systems Program, North Carolina A&T State University, 1601 E Market Street, Greensboro, NC 27411, USA; E-Mail:
| | - Zerihun Assefa
- NOAA-ISET Center, North Carolina A&T State University, 1601 E Market Street Greensboro, NC 27411, USA; E-Mail:
- Department of Chemistry, North Carolina A&T State University, 1601 E Market Street, New Science Building, Greensboro, NC 27411, USA; E-Mail:
- Authors to whom correspondence should be addressed; E-Mails: (Z.A.); (S.B.); Tel.: +1-336-285-2328/2255; Fax: +1-336-256-2542/ 334-7124
| | - Solomon Bililign
- NOAA-ISET Center, North Carolina A&T State University, 1601 E Market Street Greensboro, NC 27411, USA; E-Mail:
- Department of Physics, North Carolina A&T State University, Greensboro, 1601 E Market Street, Marteena Hall, Greensboro, NC 27411, USA; E-Mail:
- Authors to whom correspondence should be addressed; E-Mails: (Z.A.); (S.B.); Tel.: +1-336-285-2328/2255; Fax: +1-336-256-2542/ 334-7124
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Waechter H, Bescherer K, Dürr CJ, Oleschuk RD, Loock HP. 405 nm Absorption Detection in Nanoliter Volumes. Anal Chem 2009; 81:9048-54. [DOI: 10.1021/ac901696q] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Helen Waechter
- Department of Chemistry, Queen’s University, Kingston, Ontario, K7L 3N6, Canada
| | - Klaus Bescherer
- Department of Chemistry, Queen’s University, Kingston, Ontario, K7L 3N6, Canada
| | - Christoph J. Dürr
- Department of Chemistry, Queen’s University, Kingston, Ontario, K7L 3N6, Canada
| | - Richard D. Oleschuk
- Department of Chemistry, Queen’s University, Kingston, Ontario, K7L 3N6, Canada
| | - Hans-Peter Loock
- Department of Chemistry, Queen’s University, Kingston, Ontario, K7L 3N6, Canada
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31
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Wang C. Fiber loop ringdown - a time-domain sensing technique for multi-function fiber optic sensor platforms: current status and design perspectives. SENSORS (BASEL, SWITZERLAND) 2009; 9:7595-621. [PMID: 22408471 PMCID: PMC3292074 DOI: 10.3390/s91007595] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 09/09/2009] [Accepted: 09/17/2009] [Indexed: 11/16/2022]
Abstract
Fiber loop ringdown (FLRD) utilizes an inexpensive telecommunications light source, a photodiode, and a section of single-mode fiber to form a uniform fiber optic sensor platform for sensing various quantities, such as pressure, temperature, strain, refractive index, chemical species, biological cells, and small volume of fluids. In FLRD, optical losses of a light pulse in a fiber loop induced by changes in a quantity are measured by the light decay time constants. FLRD measures time to detect a quantity; thus, FLRD is referred to as a time-domain sensing technique. FLRD sensors have near real-time response, multi-pass enhanced high-sensitivity, and relatively low cost (i.e., without using an optical spectral analyzer). During the last eight years since the introduction of the original form of fiber ringdown spectroscopy, there has been increasing interest in the FLRD technique in fiber optic sensor developments, and new application potential is being explored. This paper first discusses the challenging issues in development of multi-function, fiber optic sensors or sensor networks using current fiber optic sensor sensing schemes, and then gives a review on current fiber optic sensor development using FLRD technique. Finally, design perspectives on new generation, multi-function, fiber optic sensor platforms using FLRD technique are particularly presented.
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Affiliation(s)
- Chuji Wang
- Department of Physics, and the Institute for Clean Energy Technology, Mississippi State University, Starkville, MS, 39759, USA; E-Mail: ; Tel.: +1-662-325-9455
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