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Zhang H, Luo J, Hou S, Xu Z, Evans J, He S. Incoherent broadband cavity-enhanced absorption spectroscopy for sensitive measurement of nutrients and microalgae. APPLIED OPTICS 2022; 61:3400-3408. [PMID: 35471436 DOI: 10.1364/ao.449467] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
Incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) can achieve sensitive measurements at trace concentrations for liquid phase marine samples. The IBBCEAS system consists of a cavity-enhancement module (CEM) and a transmission hyperspectral module (THM). The CEM has cavity-enhancement factors up to 78 at 550 nm. Measurements were obtained over a wide wavelength range (420-640 nm) with a halogen lamp, and the optical cavity was formed by two concave highly reflective mirrors (R=0.99). The minimum detectable absorption coefficient αmin of 7.3×10-7cm-1 at 550 nm corresponds to a limit of detection for nutrients of 780 pM. The spectral resolution of the THM is 3 nm in the wavelength range of 400 to 750 nm. We performed the IBBCEAS measurements for biological and chemical substances, including nutrients, microalgae, and Cy5 dye. The concentrations of nutrients in a deionized water environment and artificial seawater environment were measured at nanomolar levels; the concentration of microalgae phaeocystis was detected with 3.46×104/mL, and fluorescence substances such as Cy5 dye could be measured at 0.03 mg/L. Experimental results show that the IBBCEAS system has the capability for sensitive measurements of biological and chemical substances and has strong potential forin situ ecological marine environmental monitoring function.
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2
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Teggert A, Datta H, McIntosh S, Warden B, Bateson S, Abugchem F, Ali Z. Portable, low cost and sensitive cavity enhanced absorption (CEA) detection. Analyst 2021; 146:196-206. [PMID: 33140076 DOI: 10.1039/d0an01852j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Absorption is a widely used technique for a range of different applications. It has lower sensitivity than many other techniques such as fluorescence which has 100 to 1000 times higher sensitivity than absorption. Optical cavity approaches have been developed where the light passes back and forth, within the sample, between two high reflectivity mirrors to increase the pathlength and sensitivity. These approaches have not yet, however, been widely used for analytical applications and for point-of-care diagnostics. Here we show a portable cavity enhanced absorption (CEA) spectrometer and a low cost point-of-care (POC) reader with CEA detection with mechanical elements fabricated using 3D printing. The CEA spectrometer can be used in both single pass and multi-pass cavity enhanced mode to provide measurements in the visible region that are very sensitive and over a wide dynamic range. The CEA mode was shown for Rhodamine B dye to increase the pathlength 57.8 fold over single pass measurements and an LOD of 7.1 × 10-11 M. The cost of the CEA POC reader was reduced by use of narrow band LEDs, photodiodes and removal of fibre optic coupling and with a 14 fold increase in the pathlength over conventional single pass microplate readers. The CEA POC reader was demonstrated for immunoassay of C-Reactive Protein (CRP), Procalcitonin (PCT) and Interleukin 6 (IL-6), towards a three biomarker panel to aid the diagnosis of sepsis. The CEA POC reader can be integrated with wireless connectivity for cloud based data sharing. We show here the potential for the wider use of optical cavity approaches where there is a need for sensitive absorption measurements and also for low cost point-of-care diagnostics.
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Affiliation(s)
- Andrew Teggert
- Department of Clinical Biochemistry, James Cook University Hospital, Middlesbrough TS4 3BW, UK
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3
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MAITHANI SANCHI, PRADHAN MANIK. Cavity ring-down spectroscopy and its applications to environmental, chemical and biomedical systems. J CHEM SCI 2020. [DOI: 10.1007/s12039-020-01817-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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4
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Maithani S, Maity A, Pradhan M. A Prototype Evanescent Wave-Coupled Cavity Ring-down Spectrometer for Probing Real-Time Aggregation Kinetics of Gold and Silver Nanoparticles. Anal Chem 2020; 92:3998-4005. [PMID: 32008320 DOI: 10.1021/acs.analchem.9b05521] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report on the development of a simple, linear optical cavity-based system combining evanescent wave (EW) with high-sensitive cavity ring-down spectroscopy (CRDS) technique using a diode laser at 644 nm and a right-angled prism for evanescent field generation on prism surface. We characterized the setup in detail and achieved an optimum ring-down time of 159.4 ns and a minimum absorption coefficient of αmin = 1.67 × 10-6 cm-1. We utilized this setup to investigate the salt-induced aggregation kinetics of gold (Au) and silver (Ag) nanoparticles (NPs) at the prism interface with high-sensitivity. We evaluated the extinction rates on the surface due to Au and Ag NPs aggregation and examined the variations due to their respective concentrations. To demonstrate the applicability of the developed EW-CRDS prototype setup to different molecular systems, we investigated the urease-bound aggregation kinetics of the Au and Ag NPs which has not been explored earlier by this linear cavity geometry. We finally illustrated the aggregation dynamics through surface imaging, thus demonstrating an alternative analytical approach to monitor interfacial phenomena using EW-CRDS technique.
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Affiliation(s)
- Sanchi Maithani
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Salt Lake, JD Block, Sector III, Kolkata-700106, India
| | - Abhijit Maity
- Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Salt Lake, JD Block, Sector III, Kolkata-700106, India
| | - Manik Pradhan
- Department of Chemical, Biological and Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Salt Lake, JD Block, Sector III, Kolkata-700106, India.,Technical Research Centre, S. N. Bose National Centre for Basic Sciences, Salt Lake, JD Block, Sector III, Kolkata-700106, India
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5
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Bajuszova Z, Naif H, Ali Z, McGinnis J, Islam M. Cavity enhanced liquid-phase stopped-flow kinetics. Analyst 2018; 143:493-502. [PMID: 29271423 DOI: 10.1039/c7an01823a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first application of liquid-phase broadband cavity enhanced spectroscopy (BBCEAS) to the measurement of stopped-flow kinetics is reported. The stopped-flow technique is widely used for the study of the kinetics of fast liquid-phase reactions down to millisecond timescales. UV-visible absorption spectroscopy is commonly used as the detection method. Increased sensitivity can potentially allow reactions which are too fast to be measured, to be studied by slowing down the reaction rate through the use of lower concentration of reactants. A simple low cost BBCEAS experimental setup was coupled to a commercial stopped-flow instrument. Comparative standard absorption measurements were also made using a UV-visible double-beam spectrometer as the detector. Measurements were made on the reaction of potassium ferricyanide with sodium ascorbate under pseudo-first order conditions at pH 8 and pH 9.2 A cavity enhancement factor (CEF) of 78 at 434 nm was obtained whilst the minimum detectable change in the absorption coefficient αmin(t), was 1.35 × 10-5 cm-1 Hz-1/2. The kinetic data at pH 9.2 was too fast to be measured using conventional spectroscopy, whilst the BBCEAS measurements allowed 30 fold lower concentration of reactants to be used which slowed down the reaction rate enough to allow the rate constant to be determined. The BBCEAS results showed a 58 fold improvement in sensitivity over the conventional measurements and also compared favourably with the relatively few previous liquid-phase cavity enhanced kinetic studies which have been performed using significantly more complex and expensive experimental setups.
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Affiliation(s)
- Zuzana Bajuszova
- School of Science and Engineering, Teesside University, Borough Road, Middlesbrough, TS1 3BA, UK.
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6
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Gupta R, Goddard NJ. Broadband absorption spectroscopy for rapid pH measurement in small volumes using an integrated porous waveguide. Analyst 2017; 142:169-176. [DOI: 10.1039/c6an01896c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Porous waveguides integrated with microfluidics allow broadband absorption spectroscopy rapidly to measure the pH of small samples with improved sensitivity compared to single pass spectroscopy.
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Affiliation(s)
- Ruchi Gupta
- Department of Chemistry
- University of Hull
- Hull
- UK
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7
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Bajuszova Z, Ali Z, Scott S, Seetohul LN, Islam M. Cavity-Enhanced Immunoassay Measurements in Microtiter Plates Using BBCEAS. Anal Chem 2016; 88:5264-70. [PMID: 27089516 DOI: 10.1021/acs.analchem.6b00375] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report on the first detailed use of broadband cavity enhanced absorption spectroscopy (BBCEAS) as a detection system for immunoassay. A vertical R ≥ 0.99 optical cavity was integrated with a motorized XY stage, which functioned as a receptacle for 96-well microtiter plates. The custom-built cavity enhanced microplate reader was used to make measurements on a commercially available osteocalcin sandwich ELISA kit. A 30-fold increase in path length was obtained with a minimum detectable change in the absorption coefficient, αmin(t), of 5.3 × 10(-5) cm(-1) Hz(-1/2). This corresponded to a 39-fold increase in the sensitivity of measurement when directly compared to measurements in a conventional microplate reader. Separate measurements of a standard STREP-HRP colorimetric reaction in microtiter plates of differing optical quality produced an increase in sensitivity of up to 115-fold compared to a conventional microplate reader. The sensitivity of the developed setup compared favorably with previous liquid-phase cavity enhanced studies and approaches the sensitivity of typical fluorometric ELISAs. It could benefit any biochemical test which uses single pass absorption as a detection method, through either the label free detection of biologically important molecules at lower concentrations or the reduction in the amount of expensive biochemicals needed for a particular test, leading to cheaper tests.
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Affiliation(s)
- Zuzana Bajuszova
- School of Science and Engineering, Teesside University , Borough Road, Middlesbrough, TS1 3BA, United Kingdom
| | - Zulfiqur Ali
- School of Science and Engineering, Teesside University , Borough Road, Middlesbrough, TS1 3BA, United Kingdom
| | - Simon Scott
- School of Science and Engineering, Teesside University , Borough Road, Middlesbrough, TS1 3BA, United Kingdom
| | - L Nitin Seetohul
- School of Science and Engineering, Teesside University , Borough Road, Middlesbrough, TS1 3BA, United Kingdom
| | - Meez Islam
- School of Science and Engineering, Teesside University , Borough Road, Middlesbrough, TS1 3BA, United Kingdom
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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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9
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Neil SRT, Li J, Sheppard DMW, Storey J, Maeda K, Henbest KB, Hore PJ, Timmel CR, Mackenzie SR. Broadband Cavity-Enhanced Detection of Magnetic Field Effects in Chemical Models of a Cryptochrome Magnetoreceptor. J Phys Chem B 2014; 118:4177-84. [DOI: 10.1021/jp500732u] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Simon R. T. Neil
- Department of Chemistry, Physical & Theoretical Chemistry Laboratory, University of Oxford, Oxford, OX1 3QZ, United Kingdom
| | - Jing Li
- Department of Chemistry, Physical & Theoretical Chemistry Laboratory, University of Oxford, Oxford, OX1 3QZ, United Kingdom
| | - Dean M. W. Sheppard
- Department of Chemistry, Physical & Theoretical Chemistry Laboratory, University of Oxford, Oxford, OX1 3QZ, United Kingdom
| | - Jonathan Storey
- Department of Chemistry, Inorganic
Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, United Kingdom
| | - Kiminori Maeda
- Department of Chemistry, Inorganic
Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, United Kingdom
| | - Kevin B. Henbest
- Department of Chemistry, Inorganic
Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, United Kingdom
| | - P. J. Hore
- Department of Chemistry, Physical & Theoretical Chemistry Laboratory, University of Oxford, Oxford, OX1 3QZ, United Kingdom
| | - Christiane R. Timmel
- Department of Chemistry, Inorganic
Chemistry Laboratory, University of Oxford, Oxford, OX1 3QR, United Kingdom
| | - Stuart R. Mackenzie
- Department of Chemistry, Physical & Theoretical Chemistry Laboratory, University of Oxford, Oxford, OX1 3QZ, United Kingdom
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10
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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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11
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12
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Gupta R, Goddard NJ. A polymeric waveguide resonant mirror (RM) device for detection in microfluidic flow cells. Analyst 2013; 138:3209-15. [PMID: 23595031 DOI: 10.1039/c3an00263b] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel resonant mirror (RM) device, which consisted of silica sol-gel spacer and polystyrene waveguide layers on a standard microscope slide glass substrate, was developed in this work. The device was successfully used to measure the absorption spectrum of methylene blue with a limit of detection (LOD) of at most 20.8 μM at 635 nm and a minimum detectable absorption coefficient of 0.94 cm(-1). A RM device consisting of dye-doped polystyrene waveguide layer was then demonstrated to be suitable to monitor antibody-antigen (in this case, anti-IgG and IgG) binding and was shown to be capable of detecting at least 100 nM IgG. The sensitivity of the device was estimated to be 17.27° per refractive index unit (RIU), which corresponds to a resolution of 1.45 × 10(-4) RIU for the set-up used. The RM device developed in this work can be easily integrated with microfluidic devices to identify and quantify (bio) chemical species by either absorption spectroscopy or measurement of effective optical thickness or both. In addition, the device was fabricated using a simple and low cost fabrication technique, spin coating. Hence, it can be easily mass produced.
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Affiliation(s)
- Ruchi Gupta
- School of Chemical Engineering and Analytical Science, Manchester Institute of Biotechnology, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
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13
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Walsh A, Zhao D, Ubachs W, Linnartz H. Optomechanical Shutter Modulated Broad-Band Cavity–Enhanced Absorption Spectroscopy of Molecular Transients of Astrophysical Interest. J Phys Chem A 2013; 117:9363-9. [PMID: 23240889 DOI: 10.1021/jp310392n] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anton Walsh
- Raymond and Beverly Sackler
Laboratory for Astrophysics, Leiden Observatory, University of Leiden, P.O. Box 9513, NL 2300 RA Leiden, The Netherlands
| | - Dongfeng Zhao
- Raymond and Beverly Sackler
Laboratory for Astrophysics, Leiden Observatory, University of Leiden, P.O. Box 9513, NL 2300 RA Leiden, The Netherlands
| | - Wim Ubachs
- LaserLaB, Department
of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, NL 1081 HV Amsterdam,
The Netherlands
| | - Harold Linnartz
- Raymond and Beverly Sackler
Laboratory for Astrophysics, Leiden Observatory, University of Leiden, P.O. Box 9513, NL 2300 RA Leiden, The Netherlands
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14
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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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15
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Islam M, Ciaffoni L, Hancock G, Ritchie GAD. Demonstration of a novel laser-driven light source for broadband spectroscopy between 170 nm and 2.1 μm. Analyst 2013; 138:4741-5. [PMID: 23831669 DOI: 10.1039/c3an01020a] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Meez Islam
- School of Science and Engineering, Teesside University, Borough Road, Middlesbrough, TS1 3BA, UK.
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16
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Gupta R, Bastani B, Goddard NJ, Grieve B. Absorption spectroscopy in microfluidic flow cells using a metal clad leaky waveguide device with a porous gel waveguide layer. Analyst 2013; 138:307-14. [DOI: 10.1039/c2an35898k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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17
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Walker NDL, Olkhov RV, Shaw AM. pH-dependent electronic surface spectra of chromophore species in the charged silica–water interface. RSC Adv 2013. [DOI: 10.1039/c3ra40925b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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18
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Qu Z, Engstrom J, Wong D, Islam M, Kaminski CF. High sensitivity liquid phase measurements using broadband cavity enhanced absorption spectroscopy (BBCEAS) featuring a low cost webcam based prism spectrometer. Analyst 2013; 138:6372-9. [DOI: 10.1039/c3an01441j] [Citation(s) in RCA: 11] [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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19
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Kiwanuka SS, Laurila TK, Frank JH, Esposito A, Blomberg von der Geest K, Pancheri L, Stoppa D, Kaminski CF. Development of Broadband Cavity Ring-Down Spectroscopy for Biomedical Diagnostics of Liquid Analytes. Anal Chem 2012; 84:5489-93. [DOI: 10.1021/ac301108q] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- S.-S. Kiwanuka
- Department
of Chemical Engineering
and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, U.K
| | - T. K. Laurila
- Department
of Chemical Engineering
and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, U.K
- Metrology Research Institute, Aalto University, Espoo, Finland
- Centre for Metrology and Accreditation (MIKES), Espoo, Finland
| | - J. H. Frank
- Combustion Research Facility, Sandia National Laboratories, Livermore California
94551, United States
| | - A. Esposito
- Medical
Research Council Cancer
Cell Unit, Hutchison/MRC Research Centre, Cambridge, U.K
| | | | - L. Pancheri
- Fondazione Bruno Kessler (FBK), Trento, Italy
| | - D. Stoppa
- Fondazione Bruno Kessler (FBK), Trento, Italy
| | - C. F. Kaminski
- Department
of Chemical Engineering
and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, U.K
- SAOT School of Advanced Optical
Technologies, Max Planck Institute for the Science of Light, University of Erlangen-Nuremberg, Guenther-Scharowsky-Strasse
1, D-91058 Erlangen, Germany
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20
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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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21
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Neil SRT, Rushworth CM, Vallance C, Mackenzie SR. Broadband cavity-enhanced absorption spectroscopy for real time, in situ spectral analysis of microfluidic droplets. LAB ON A CHIP 2011; 11:3953-5. [PMID: 22020554 DOI: 10.1039/c1lc20854c] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Broadband cavity-enhanced absorption spectroscopy has been used to record, in real time, the absorption spectrum of microlitre volume aqueous phase droplets within a microfluidic chip assembly. Using supercontinuum radiation and broadband coated external mirrors, the full visible spectrum (430 nm < λ < 700 nm) of each passing droplet is acquired in situ at high repetition rates (273 Hz/3.66 ms acquisition time) and high sensitivity (α(min) < 10(-2) cm(-1)). The possibilities for further improvements in sensitivity and acquisition rate using custom designed chips are discussed.
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Affiliation(s)
- Simon R T Neil
- Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, Oxford, UK
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Maeda K, Neil SRT, Henbest KB, Weber S, Schleicher E, Hore PJ, Mackenzie SR, Timmel CR. Following Radical Pair Reactions in Solution: A Step Change in Sensitivity Using Cavity Ring-Down Detection. J Am Chem Soc 2011; 133:17807-15. [DOI: 10.1021/ja206783t] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kiminori Maeda
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, Oxford, OX1 3QR, U.K
- Centre for Advanced Electron Spin Resonance, University of Oxford, OX1 3QR, U.K
| | - Simon R. T. Neil
- Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, Oxford, OX1 3QZ, U.K
| | - Kevin B. Henbest
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, Oxford, OX1 3QR, U.K
- Centre for Advanced Electron Spin Resonance, University of Oxford, OX1 3QR, U.K
| | - Stefan Weber
- Institut für Physikalische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstraße 21, 79104 Freiburg, Germany
| | - Erik Schleicher
- Institut für Physikalische Chemie, Albert-Ludwigs-Universität Freiburg, Albertstraße 21, 79104 Freiburg, Germany
| | - P. J. Hore
- Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, Oxford, OX1 3QZ, U.K
| | - Stuart R. Mackenzie
- Department of Chemistry, University of Oxford, Physical and Theoretical Chemistry Laboratory, Oxford, OX1 3QZ, U.K
| | - Christiane R. Timmel
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, Oxford, OX1 3QR, U.K
- Centre for Advanced Electron Spin Resonance, University of Oxford, OX1 3QR, U.K
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PCF-based cavity enhanced spectroscopic sensors for simultaneous multicomponent trace gas analysis. SENSORS 2011; 11:1620-40. [PMID: 22319372 PMCID: PMC3274003 DOI: 10.3390/s110201620] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 11/16/2010] [Accepted: 01/04/2011] [Indexed: 12/04/2022]
Abstract
A multiwavelength, multicomponent CRDS gas sensor operating on the basis of a compact photonic crystal fibre supercontinuum light source has been constructed. It features a simple design encompassing one radiation source, one cavity and one detection unit (a spectrograph with a fitted ICCD camera) that are common for all wavelengths. Multicomponent detection capability of the device is demonstrated by simultaneous measurements of the absorption spectra of molecular oxygen (spin-forbidden b-X branch) and water vapor (polyads 4v, 4v + δ) in ambient atmospheric air. Issues related to multimodal cavity excitation, as well as to obtaining the best signal-to-noise ratio are discussed together with methods for their practical resolution based on operating the cavity in a “quasi continuum” mode and setting long camera gate widths, respectively. A comprehensive review of multiwavelength CRDS techniques is also given.
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25
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Denzer W, Hancock G, Islam M, Langley CE, Peverall R, Ritchie GAD, Taylor D. Trace species detection in the near infrared using Fourier transform broadband cavity enhanced absorption spectroscopy: initial studies on potential breath analytes. Analyst 2011; 136:801-6. [DOI: 10.1039/c0an00462f] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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26
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Schnippering M, Neil SRT, Mackenzie SR, Unwin PR. Evanescent wave cavity-based spectroscopic techniques as probes of interfacial processes. Chem Soc Rev 2011; 40:207-20. [DOI: 10.1039/c0cs00017e] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Liu C, Rees EJ, Laurila T, Jian S, Kaminski CF. An adaptive filter for studying the life cycle of optical rogue waves. OPTICS EXPRESS 2010; 18:26113-26122. [PMID: 21164960 DOI: 10.1364/oe.18.026113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We present an adaptive numerical filter for analyzing fiber-length dependent properties of optical rogue waves, which are highly intense and extremely red-shifted solitons that arise during supercontinuum generation in photonic crystal fiber. We use this filter to study a data set of 1000 simulated supercontinuum pulses, produced from 5 ps pump pulses containing random noise. Optical rogue waves arise in different supercontinuum pulses at various positions along the fiber, and exhibit a lifecycle: their intensity peaks over a finite range of fiber length before declining slowly.
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Affiliation(s)
- Chu Liu
- Institute of Lightwave Technology, Key Lab of All Optical Network and Advanced Telecommunication Network of EMC, Beijing Jiaotong University, Beijing 100044, China
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Kiwanuka SS, Laurila T, Kaminski CF. Sensitive Method for the Kinetic Measurement of Trace Species in Liquids Using Cavity Enhanced Absorption Spectroscopy with Broad Bandwidth Supercontinuum Radiation. Anal Chem 2010; 82:7498-501. [DOI: 10.1021/ac1012255] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ssegawa-Ssekintu Kiwanuka
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, U.K., and Friedrich Alexander University Erlangen-Nuremberg, School for Advanced Optical Technologies, Paul-Gordan-Str. 6, 91052 Erlangen, Germany
| | - Toni Laurila
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, U.K., and Friedrich Alexander University Erlangen-Nuremberg, School for Advanced Optical Technologies, Paul-Gordan-Str. 6, 91052 Erlangen, Germany
| | - Clemens F. Kaminski
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, U.K., and Friedrich Alexander University Erlangen-Nuremberg, School for Advanced Optical Technologies, Paul-Gordan-Str. 6, 91052 Erlangen, Germany
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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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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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