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Zhang B, Shi Y. Design of flexible hollow core fiber based photoacoustic gas sensor with high cell constant and compact size. OPTICS EXPRESS 2023; 31:34708-34720. [PMID: 37859221 DOI: 10.1364/oe.500212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 09/20/2023] [Indexed: 10/21/2023]
Abstract
Here we designed, optimized, and proposed a flexible low frequency resonant photoacoustic (PA) gas sensor by using a large core leaky hollow core fiber (L-HCF). The influences from the dimensions, the transmission loss and the bending loss on the performance of the flexible PA gas sensor were systematically investigated. In this work, the optimized inner diameter and length of the L-HCF were 1.7 mm and 300 mm, respectively. The L-HCF based PA cell constant was calculated to be 12115 Pa/(W·cm-1). The minimum detectable limit (MDL) for trace C2H2 detection achieved 23.0 ppb when the lock-in integration time was 200 s by using a near-infrared distributed feedback (DFB) laser source and a low-cost electrical micro-electro-mechanical system (MEMS) microphone. Besides, the amplitude decay ratio of the of the PA signal was only 11.3% when the bending radius of the L-HCF was 100 mm. The normalized noise equivalent absorption (NNEA) coefficient is calculated to be 6.6 × 10-9 W•cm-1•Hz-1/2. The L-HCF based PA cell was proved to own merits of compact size, high cell constant, small gas volume and low cost.
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2
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Yoon Y, Breshike CJ, Kendziora CA, Furstenberg R, Andrew McGill R. Simultaneous real-time spectroscopy using a broadband IR laser source. OPTICS EXPRESS 2021; 29:8902-8913. [PMID: 33820331 DOI: 10.1364/oe.419262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 02/20/2021] [Indexed: 06/12/2023]
Abstract
In this study, we have developed a simultaneous grating spectroscopy using a broadband IR laser source capable of detecting moving targets in real time. The broadband IR laser source operated in pulsed mode provides a broad spectral range, which covers absorption bands of many chemical analytes. The laser operating conditions were optimized to cover the broadest wavelength range spanning spectral features for the analytes of interest, based on a detailed understanding of the broadband source. This measured the signal from two samples, a 1% acetaminophen KBr pellet sample and toluene in a gas cell. These samples were characterized by illuminating them with the IR broadband source and collecting the transmitted or reflected signal through a grating spectrometer and onto an IR focal plane array (FPA). The results clearly show discrete peaks comparable to the FTIR reference spectra and the spectral features of the samples were successfully discriminated. We believe that the proof of concepts presented here are of broad applicability and will aid advanced real-time standoff detection research.
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Zhou T, Wu T, Wu Q, Chen W, Wu M, Ye C, He X. Real-Time Monitoring of 13C- and 18O-Isotopes of Human Breath CO 2 Using a Mid-Infrared Hollow Waveguide Gas Sensor. Anal Chem 2020; 92:12943-12949. [PMID: 32864957 DOI: 10.1021/acs.analchem.0c01586] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Real-time measuring of CO2 isotopes (13CO2, 12CO2, and 18OC16O) in exhaled breath using a mid-infrared hollow waveguide gas sensor incorporating a 2.73 μm distributed feedback laser was proposed and demonstrated for the first time based on calibration-free wavelength modulation spectroscopy. The measurement precisions for δ13C and δ18O were, respectively, 0.26 and 0.57‰ for an integration time of 131 s by Allan variance analysis. These measurement precisions achieved in the present work were at least 3.5 times better than those reported using direct absorption spectroscopy and 1.3 times better than those obtained by calibration-needed wavelength modulation absorption spectroscopy. Continuous measurement of three isotopes in the breathing cycle was performed. Alveolar gas from the expirogram was identified, and the 13C/12C and 18O/16O ratios were found to be almost constant during the alveolar plateau, which enables optimization of breath sampling and provides accurate information on metabolic processes. The 13C/12C and 18O/16O isotope ratios at the alveolar plateau of five breath cycles were averaged, yielding δ13C and δ18O values of (-24.3 ± 3.4) and (-30.7 ± 2.6) ‰, respectively. This study demonstrates the feasibility of real-time analysis of 13C- and 18O-isotopes of human breath CO2 in clinical applications and shows its potential for diagnosing respiratory-related diseases with high sensitivity, selectivity, and specificity.
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Affiliation(s)
- Tao Zhou
- Key Laboratory of Nondestructive Test (Ministry of Education), Nanchang Hangkong University, Nanchang 330063, China
| | - Tao Wu
- Key Laboratory of Nondestructive Test (Ministry of Education), Nanchang Hangkong University, Nanchang 330063, China
| | - Qiang Wu
- Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle Upon Tyne NE1 8ST, U.K.,Key Laboratory of Nondestructive Test (Ministry of Education), Nanchang Hangkong University, Nanchang 330063, China
| | - Weidong Chen
- Laboratoire de Physicochimie de l'Atmosphère, Université du Littoral Côte d'Opale 189A, Av. Maurice Schumann, Dunkerque 59140, France
| | - Mingwei Wu
- Shenzhen Hospital, Southern Medical University, 1333 Xinhu Rd, Shenzhen 518000, China
| | - Chenwen Ye
- Key Laboratory of Nondestructive Test (Ministry of Education), Nanchang Hangkong University, Nanchang 330063, China
| | - Xingdao He
- Key Laboratory of Nondestructive Test (Ministry of Education), Nanchang Hangkong University, Nanchang 330063, China
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Nikodem M. Laser-Based Trace Gas Detection inside Hollow-Core Fibers: A Review. MATERIALS (BASEL, SWITZERLAND) 2020; 13:E3983. [PMID: 32916799 PMCID: PMC7557433 DOI: 10.3390/ma13183983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 08/28/2020] [Accepted: 09/07/2020] [Indexed: 11/29/2022]
Abstract
Thanks to the guidance of an optical wave in air, hollow-core fibers may serve as sampling cells in an optical spectroscopic system. This paper reviews applications of hollow-core optical fibers to laser-based gas sensing. Three types of hollow-core fibers are discussed: Hollow capillary waveguides, photonic band-gap fibers, and negative curvature fibers. Their advantages and drawbacks when used for laser-based trace gas detection are analyzed. Various examples of experimental sensing systems demonstrated in the literature over the past 20 years are discussed.
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Affiliation(s)
- Michal Nikodem
- Department of Optics and Photonics, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland
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Glöckler J, Jaeschke C, Kocaöz Y, Kokoric V, Tütüncü E, Mitrovics J, Mizaikoff B. iHWG-MOX: A Hybrid Breath Analysis System via the Combination of Substrate-Integrated Hollow Waveguide Infrared Spectroscopy with Metal Oxide Gas Sensors. ACS Sens 2020; 5:1033-1039. [PMID: 32189494 DOI: 10.1021/acssensors.9b02554] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
According to their materials and operating parameters, metal oxide (MOX) sensors respond to target gases only by a change in sensor resistance with a lack in selectivity. By the use of infrared spectroscopy, highly discriminatory information from samples at a molecular level can be obtained and the selectivity can be enhanced. A low-volume gas cell was developed for a commercially available semiconducting MOX methane gas sensor and coupled directly to a mid-infrared gas sensor based on substrate-integrated hollow waveguide (iHWG) technology combined with a Fourier transform infrared spectrometer. This study demonstrates a sensing process with combined orthogonal sensors for fast, time-resolved, and synergic detection of methane and carbon dioxide in gas samples.
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Affiliation(s)
- Johannes Glöckler
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Carsten Jaeschke
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
- JLM Innovation GmbH, Vor dem Kreuzberg 17, 72070 Tübingen, Germany
| | - Yusuf Kocaöz
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Vjekoslav Kokoric
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Erhan Tütüncü
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Jan Mitrovics
- JLM Innovation GmbH, Vor dem Kreuzberg 17, 72070 Tübingen, Germany
| | - Boris Mizaikoff
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
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Zhou T, Wu T, Wu Q, Ye C, Hu R, Chen W, He X. Real-time measurement of CO 2 isotopologue ratios in exhaled breath by a hollow waveguide based mid-infrared gas sensor. OPTICS EXPRESS 2020; 28:10970-10980. [PMID: 32403618 DOI: 10.1364/oe.385103] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 03/05/2020] [Indexed: 06/11/2023]
Abstract
A hollow waveguide (HWG) based mid-infrared gas sensor using a 2.73 µm distributed feedback (DFB) laser was developed for simultaneously measuring the concentration changes of the three isotopologues 13CO2, 12CO2, and 18OC16O in exhaled breath by direct absorption spectroscopy, and then determining the 13CO2/12CO2 isotope ratio (δ13C) and 18OC16O/12CO2 isotope ratio (δ18O). The HWG sensor showed a fast response time of 3 s. Continuous measurement of δ13C and δ18O in the standard CO2 sample with known isotopic ratios for ∼2 h was performed. Precisions of 2.20‰ and 1.98‰ for δ13C and δ18O respectively at optimal integration time of 734 s were estimated from Allan variance analysis. Accuracy of -0.49‰ and -1.20‰ for δ13C and δ18O, respectively, were obtained with comparison to the values of the reference standard. The Kalman filtering method was employed to improve the precision and accuracy of the HWG sensor while maintaining high time resolution. Precision of 5.45‰ and 4.88‰ and the accuracy of 0.21‰ and -1.13‰ for δ13C and δ18O, respectively, were obtained at the integration time of 0.54 s with the application of Kalman filtering. The concentrations of 12CO2, 13CO2 and 18OC16O in breath cycles were measured and processed by Kalman filtering in real time. The measured values of δ18O and δ13C in exhaled breath were estimated to be -21.35‰ and -33.64‰, respectively, with the integration time of 1 s. This study demonstrates the ability of the HWG sensor to obtain δ13C and δ18O values in breath samples and its potential for immediate respiratory monitoring and disease diagnosis.
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Seichter F, Vogt JA, Wachter U, Radermacher P, Mizaikoff B. Strategies for 13C enrichment calculation in Fourier-transform infrared CO2 spectra containing spectral overlapping and nonlinear abundance-amount relations utilizing response surface fits. Anal Chim Acta 2020; 1095:48-60. [DOI: 10.1016/j.aca.2019.10.038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 09/17/2019] [Accepted: 10/18/2019] [Indexed: 11/28/2022]
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8
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Zhou S, Liu N, Shen C, Zhang L, He T, Yu B, Li J. An adaptive Kalman filtering algorithm based on back-propagation (BP) neural network applied for simultaneously detection of exhaled CO and N 2O. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 223:117332. [PMID: 31288168 DOI: 10.1016/j.saa.2019.117332] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 06/17/2019] [Accepted: 06/28/2019] [Indexed: 06/09/2023]
Abstract
A compact high-resolution spectroscopic sensor using a thermoelectrically (TE) cooled continuous-wave (CW) room temperature (RT) quantum cascade laser (QCL) was demonstrated for simultaneous measurements of exhaled carbon monoxide (CO) and nitrous oxide (N2O). The sampling pressure was optimized to improve the sensitivity, the optimal pressure was determined to be 150 mbar based on an optical density analysis of simulated and measured absorption spectra. An adaptive Kalman filtering algorithm based on back-propagation (BP) neural network was developed and proposed for real-time exhaled breath analysis in order to perform fast and high precision on-line measurements. The detection limits (1σ) of 1.14 ppb and 1.12 ppb were experimentally achieved for CO and N2O detection, respectively. Typical concentrations of exhaled CO and N2O from smokers and non-smokers were analyzed. The experimental results indicated that the state-of-the-art CW-QCL based sensor has a great potential for non-invasive, on-line identification and quantification of biomarkers in human breath.
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Affiliation(s)
- Sheng Zhou
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 230601 Hefei, China; Laser Spectroscopy and Sensing Laboratory, Anhui University, 230601 Hefei, China.
| | - Ningwu Liu
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 230601 Hefei, China; Laser Spectroscopy and Sensing Laboratory, Anhui University, 230601 Hefei, China
| | - Chongyang Shen
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 230601 Hefei, China; Laser Spectroscopy and Sensing Laboratory, Anhui University, 230601 Hefei, China
| | - Lei Zhang
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 230601 Hefei, China; Laser Spectroscopy and Sensing Laboratory, Anhui University, 230601 Hefei, China
| | - Tianbo He
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 230601 Hefei, China; Laser Spectroscopy and Sensing Laboratory, Anhui University, 230601 Hefei, China
| | - Benli Yu
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 230601 Hefei, China; Laser Spectroscopy and Sensing Laboratory, Anhui University, 230601 Hefei, China
| | - Jingsong Li
- Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education, Anhui University, 230601 Hefei, China; Laser Spectroscopy and Sensing Laboratory, Anhui University, 230601 Hefei, China.
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9
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Robinson I, Butcher HL, Macleod NA, Weidmann D. Hollow waveguide integrated laser spectrometer for 13CO 2/ 12CO 2 analysis. OPTICS EXPRESS 2019; 27:35670-35688. [PMID: 31878735 DOI: 10.1364/oe.27.035670] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 11/13/2019] [Indexed: 06/10/2023]
Abstract
Using hollow waveguide hybrid optical integration, a miniaturized mid-infrared laser absorption spectrometer for 13CO2/12CO2 isotopologue ratio analysis is presented. The laser analyzer described focuses on applications where samples contain a few percent of CO2, such as breath analysis and characterization of geo-carbon fluxes, where miniaturization facilitates deployment. As part of the spectrometer design, hollow waveguide mode coupling and propagation is analyzed to inform the arrangement of the integrated optical system. The encapsulated optical system of the spectrometer occupies a volume of 158 × 60 × 30 mm3 and requires a low sample volume (56 µL) for analysis, while integrating a quantum cascade laser, coupling lens, hollow waveguide cell and optical detector into a single copper alloy substrate. The isotopic analyzer performance is characterized through robust error propagation analysis, from spectral inversion to calibration errors. The analyzer achieves a precision of 0.2‰ in 500 s integration. A stability time greater than 500 s was established to allow two-point calibration. The accuracy achieved is 1.5‰, including a contribution of 0.7‰ from calibrant gases that can be addressed with improved calibration mixtures.
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10
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Patrizi B, Siciliani de Cumis M, Viciani S, D'Amato F. Dioxin and Related Compound Detection: Perspectives for Optical Monitoring. Int J Mol Sci 2019; 20:E2671. [PMID: 31151286 PMCID: PMC6600530 DOI: 10.3390/ijms20112671] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 05/28/2019] [Accepted: 05/28/2019] [Indexed: 12/20/2022] Open
Abstract
Dioxins and related compounds are environmental xenobiotics that are dangerous to human life, due to the accumulation and persistence in the environment and in the food chain. Cancer, reproductive and developmental issues, and damage to the immune system and endocrine system are only a few examples of the impact of such substances in everyday life. For these reasons, it is fundamental to detect and monitor these molecules in biological samples. The consolidated technique for analytical evaluation is gas chromatography combined with high-resolution mass spectrometry. Nowadays, the development of mid-infrared optical components like broadband laser sources, optical frequency combs, high performance Fourier-transform infrared spectroscopy, and plasmonic sensors open the way to new techniques for detection and real time monitoring of these organic pollutants in gaseous or liquid phase, with sufficient sensitivity and selectivity, and in short time periods. In this review, we report the latest techniques for the detection of dioxins, furans and related compounds based on optical and spectroscopic methods, looking at future perspectives.
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Affiliation(s)
- Barbara Patrizi
- National Institute of Optics-National Research Council (INO-CNR), Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Italy.
- European Laboratory for Non-Linear Spectroscopy (LENS), Via Nello Carrara n. 1, 50019 Sesto Fiorentino, Italy.
| | - Mario Siciliani de Cumis
- National Institute of Optics-National Research Council (INO-CNR), Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Italy.
- Italian Space Agency, Contrada Terlecchia snc, 75100 Matera, Italy.
| | - Silvia Viciani
- National Institute of Optics-National Research Council (INO-CNR), Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Italy.
- European Laboratory for Non-Linear Spectroscopy (LENS), Via Nello Carrara n. 1, 50019 Sesto Fiorentino, Italy.
| | - Francesco D'Amato
- National Institute of Optics-National Research Council (INO-CNR), Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Italy.
- European Laboratory for Non-Linear Spectroscopy (LENS), Via Nello Carrara n. 1, 50019 Sesto Fiorentino, Italy.
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11
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Hinkov B, Hayden J, Szedlak R, Martin-Mateos P, Jerez B, Acedo P, Strasser G, Lendl B. High frequency modulation and (quasi) single-sideband emission of mid-infrared ring and ridge quantum cascade lasers. OPTICS EXPRESS 2019; 27:14716-14724. [PMID: 31163916 DOI: 10.1364/oe.27.014716] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 04/05/2019] [Indexed: 06/09/2023]
Abstract
We investigate the high frequency modulation characteristics of mid-infrared surface-emitting ring and edge-emitting ridge quantum cascade lasers (QCLs). In particular, a detailed comparison between circular ring devices and ridge-QCLs from the same laser material, which have a linear waveguide in a "Fabry-Pérot (FP) type" cavity, reveals distinct similarities and differences. Both device types are single-mode emitting, based on either 2 nd- (ring-QCL) or 1 st-order (ridge-QCL) distributed feedback (DFB) gratings with an emission wavelength around 7.56 μm. Their modulation characteristics are investigated in the frequency-domain using an optical frequency-to-amplitude conversion technique based on the ro-vibrational absorptions of CH 4. We observe that the amplitude of frequency tuning Δf over intensity modulation index m as function of the modulation frequency behaves similarly for both types of devices, while the ring-QCLs typically show higher values. The frequency-to-intensity modulation (FM-IM) phase shift shows a decrease starting from ∼72 ∘ at a modulation frequency of 800 kHz to about 0 ∘ at 160 MHz. In addition, we also observe a quasi single-sideband (qSSB) regime for modulation frequencies above 100 MHz, which is identified by a vanishing -1 st-order sideband for both devices. This special FM-state can be observed in DFB QCLs and is in strong contrast to the behavior of regular DFB diode lasers, which do not achieve any significant sideband suppression. By analyzing these important high frequency characteristics of ring-QCLs and comparing them to ridge DFB-QCLs, it shows the potential of intersubband devices for applications in e.g. novel spectroscopic techniques and highly-integrated and high-bitrate free-space data communication. In addition, the obtained results close an existing gap in literature for high frequency modulation characteristics of QCLs.
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12
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Mid-Infrared Tunable Laser-Based Broadband Fingerprint Absorption Spectroscopy for Trace Gas Sensing: A Review. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9020338] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The vast majority of gaseous chemical substances exhibit fundamental rovibrational absorption bands in the mid-infrared spectral region (2.5–25 μm), and the absorption of light by these fundamental bands provides a nearly universal means for their detection. A main feature of optical techniques is the non-intrusive in situ detection of trace gases. We reviewed primarily mid-infrared tunable laser-based broadband absorption spectroscopy for trace gas detection, focusing on 2008–2018. The scope of this paper is to discuss recent developments of system configuration, tunable lasers, detectors, broadband spectroscopic techniques, and their applications for sensitive, selective, and quantitative trace gas detection.
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Isensee K, Kröger-Lui N, Petrich W. Biomedical applications of mid-infrared quantum cascade lasers - a review. Analyst 2019; 143:5888-5911. [PMID: 30444222 DOI: 10.1039/c8an01306c] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Mid-infrared spectroscopy has been applied to research in biology and medicine for more than 20 years and conceivable applications have been identified. More recently, these applications have been shown to benefit from the use of quantum cascade lasers due to their specific properties, namely high spectral power density, small beam parameter product, narrow emission spectrum and, if needed, tuning capabilities. This review provides an overview of the achievements and illustrates some applications which benefit from the key characteristics of quantum cascade laser-based mid-infrared spectroscopy using examples such as breath analysis, the investigation of serum, non-invasive glucose monitoring in bulk tissue and the combination of spectroscopy and microscopy of tissue thin sections for rapid histopathology.
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Affiliation(s)
- Katharina Isensee
- Kirchhoff-Institute for Physics, Heidelberg University, INF 277, 69120 Heidelberg, Germany.
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14
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Cascade laser sensing concepts for advanced breath diagnostics. Anal Bioanal Chem 2018; 411:1679-1686. [PMID: 30565171 DOI: 10.1007/s00216-018-1509-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 11/12/2018] [Accepted: 11/21/2018] [Indexed: 01/03/2023]
Abstract
With more than a thousand constituents at trace level concentrations, exhaled breath analysis (EBA) allows for non-invasive point-of-care (POC) disease diagnostics and metabolic status monitoring in or close to real-time. A number of biomarkers in breath may be used to not only identify diseases and disease progression but also to monitor therapeutic interventions. Although the relationship of selected breath components/biomarkers with certain disease pathologies is well established, diagnosing the exhaled breath composition remains an analytical and practical challenge due to the concentration levels of molecules of interest, i.e., low parts-per-billion (ppb) regime and below. Besides the analytical assessment of breath components via conventional methods such as gas chromatography coupled to mass spectrometry and related techniques, the application of cascade laser spectroscopy (CLS) is relatively new and exhibits several advantages when aiming for compact and user-friendly trace gas sensors with high molecular selectivity, the required sensitivity, and potentially reasonable instrumental costs. This trend article highlights the current status and potential of CLS in breath diagnostics with a focus on recent advancements in instrumentation and application along with future prospects and challenges. Graphical abstract Cascade laser technology in the mid-infrared spectral range enables sensitive and molecularly selective exhaled breath analysis with near real-time response, label-free detection, and point-of-care feasibility.
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15
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Cheng J, Shao J, Ye Y, Zhao Y, Huang C, Wang L, Li M. Microfluidic Preconcentration Chip with Self-Assembled Chemical Modified Surface for Trace Carbonyl Compounds Detection. SENSORS (BASEL, SWITZERLAND) 2018; 18:E4402. [PMID: 30551558 PMCID: PMC6308564 DOI: 10.3390/s18124402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 12/04/2018] [Accepted: 12/10/2018] [Indexed: 11/22/2022]
Abstract
Carbonyl compounds in water sources are typical characteristic pollutants, which are important indicators in the health risk assessment of water quality. Commonly used analytical chemistry methods face issues such as complex operations, low sensitivity, and long analysis times. Here, we report a silicon microfluidic device based on click chemical surface modification that was engineered to achieve rapid, convenient and efficient capture of trace level carbonyl compounds in liquid solvent. The micro pillar arrays of the chip and microfluidic channels were designed under the basis of finite element (FEM) analysis and fabricated by the microelectromechanical systems (MEMS) technique. The surface of the micropillars was sputtered with precious metal silver and functionalized with the organic substance amino-oxy dodecane thiol (ADT) by self-assembly for capturing trace carbonyl compounds. The detection of ppb level fluorescent carbonyl compounds demonstrates that the strategy proposed in this work shows great potential for rapid water quality testing and for other samples with trace carbonyl compounds.
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Affiliation(s)
- Jie Cheng
- R&D Center of HealthCare Electronics, Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China.
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 101400, China.
| | - Jianwei Shao
- The State Key Laboratory of Chemical Resource Engineering, Beijing 100029, China.
- College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Yifei Ye
- R&D Center of HealthCare Electronics, Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China.
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 101400, China.
| | - Yang Zhao
- R&D Center of HealthCare Electronics, Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China.
| | - Chengjun Huang
- R&D Center of HealthCare Electronics, Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China.
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 101400, China.
| | - Li Wang
- The State Key Laboratory of Chemical Resource Engineering, Beijing 100029, China.
- College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Mingxiao Li
- R&D Center of HealthCare Electronics, Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China.
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Tütüncü E, Nägele M, Becker S, Fischer M, Koeth J, Wolf C, Köstler S, Ribitsch V, Teuber A, Gröger M, Kress S, Wepler M, Wachter U, Vogt J, Radermacher P, Mizaikoff B. Advanced Photonic Sensors Based on Interband Cascade Lasers for Real-Time Mouse Breath Analysis. ACS Sens 2018; 3:1743-1749. [PMID: 30074387 DOI: 10.1021/acssensors.8b00477] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A multiparameter gas sensor based on distributed feedback interband cascade lasers emitting at 4.35 μm and ultrafast electro-spun luminescence oxygen sensors has been developed for the quantification and continuous monitoring of 13CO2/12CO2 isotopic ratio changes and oxygen in exhaled mouse breath samples. Mid-infrared absorption spectra for quantitatively monitoring the enrichment of 13CO2 levels were recorded in a miniaturized dual-channel substrate-integrated hollow waveguide using balanced ratiometric detection, whereas luminescence quenching was used for synchronously detecting exhaled oxygen levels. Allan variance analysis verified a CO2 measurement precision of 1.6‰ during a 480 s integration time. Routine online monitoring of exhaled mouse breath was performed in 14 mechanically ventilated and instrumented mice and demonstrated the feasibility of online isotope-selective exhaled breath analysis within microliters of probed gas samples using the reported combined sensor platform.
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Affiliation(s)
- Erhan Tütüncü
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Markus Nägele
- OptoPrecision GmbH, Auf der Höhe 15, 28357 Bremen, Germany
| | - Steffen Becker
- nanoplus Nanosystems and Technologies GmbH, Oberer Kirschberg 4, 97218 Gerbrunn, Germany
| | - Marc Fischer
- nanoplus Nanosystems and Technologies GmbH, Oberer Kirschberg 4, 97218 Gerbrunn, Germany
| | - Johannes Koeth
- nanoplus Nanosystems and Technologies GmbH, Oberer Kirschberg 4, 97218 Gerbrunn, Germany
| | - Christian Wolf
- Joanneum Research
Forschungsgesellschaft mbH., Materials - Institut für Oberflächentechnologien
und Photonik, Franz-Pichler-Straße 30, 8160 Weiz, Austria
| | - Stefan Köstler
- Joanneum Research
Forschungsgesellschaft mbH., Materials - Institut für Oberflächentechnologien
und Photonik, Franz-Pichler-Straße 30, 8160 Weiz, Austria
| | | | - Andrea Teuber
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Michael Gröger
- Institute of Anesthesiologic Pathophysiology and Method Development, Ulm University Medical Center, Helmholtzstr. 8/1, 89081 Ulm, Germany
| | - Sandra Kress
- Institute of Anesthesiologic Pathophysiology and Method Development, Ulm University Medical Center, Helmholtzstr. 8/1, 89081 Ulm, Germany
| | - Martin Wepler
- Institute of Anesthesiologic Pathophysiology and Method Development, Ulm University Medical Center, Helmholtzstr. 8/1, 89081 Ulm, Germany
| | - Ulrich Wachter
- Institute of Anesthesiologic Pathophysiology and Method Development, Ulm University Medical Center, Helmholtzstr. 8/1, 89081 Ulm, Germany
| | - Josef Vogt
- Institute of Anesthesiologic Pathophysiology and Method Development, Ulm University Medical Center, Helmholtzstr. 8/1, 89081 Ulm, Germany
| | - Peter Radermacher
- Institute of Anesthesiologic Pathophysiology and Method Development, Ulm University Medical Center, Helmholtzstr. 8/1, 89081 Ulm, Germany
| | - Boris Mizaikoff
- Institute of Analytical and Bioanalytical Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
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17
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Wallace MAG, Pleil JD. Evolution of clinical and environmental health applications of exhaled breath research: Review of methods and instrumentation for gas-phase, condensate, and aerosols. Anal Chim Acta 2018; 1024:18-38. [PMID: 29776545 PMCID: PMC6082128 DOI: 10.1016/j.aca.2018.01.069] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Revised: 01/29/2018] [Accepted: 01/31/2018] [Indexed: 12/20/2022]
Abstract
Human breath, along with urine and blood, has long been one of the three major biological media for assessing human health and environmental exposure. In fact, the detection of odor on human breath, as described by Hippocrates in 400 BC, is considered the first analytical health assessment tool. Although less common in comparison to contemporary bio-fluids analyses, breath has become an attractive diagnostic medium as sampling is non-invasive, unlimited in timing and volume, and does not require clinical personnel. Exhaled breath, exhaled breath condensate (EBC), and exhaled breath aerosol (EBA) are different types of breath matrices used to assess human health and disease state. Over the past 20 years, breath research has made many advances in assessing health state, overcoming many of its initial challenges related to sampling and analysis. The wide variety of sampling techniques and collection devices that have been developed for these media are discussed herein. The different types of sensors and mass spectrometry instruments currently available for breath analysis are evaluated as well as emerging breath research topics, such as cytokines, security and airport surveillance, cellular respiration, and canine olfaction.
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Affiliation(s)
- M Ariel Geer Wallace
- U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, 109 T.W. Alexander Drive, Research Triangle Park, NC, 27711, USA.
| | - Joachim D Pleil
- U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, 109 T.W. Alexander Drive, Research Triangle Park, NC, 27711, USA.
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18
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Bai Y, Zhang D, Li C, Liu C, Cheng JX. Bond-Selective Imaging of Cells by Mid-Infrared Photothermal Microscopy in High Wavenumber Region. J Phys Chem B 2017; 121:10249-10255. [PMID: 29035533 DOI: 10.1021/acs.jpcb.7b09570] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using a visible beam to probe the thermal effect induced by infrared absorption, mid-infrared photothermal (MIP) microscopy allows bond-selective chemical imaging at submicron spatial resolution. Current MIP microscopes cannot reach the high wavenumber region due to the limited tunability of the existing quantum cascade laser source. We extend the spectral range of MIP microscopy by difference frequency generation (DFG) from two chirped femtosecond pulses. Flexible wavelength tuning in both C-D and C-H regions was achieved with mid-infrared power up to 22.1 mW and spectral width of 29.3 cm-1. Distribution of fatty acid in live human lung cancer cells was revealed by MIP imaging of the C-D bond at 2192 cm-1.
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Affiliation(s)
- Yeran Bai
- National Laboratory on High Power Laser and Physics , Shanghai 201800, China.,Key Laboratory of High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences , Shanghai 201800, China.,University of Chinese Academy of Sciences , Beijing 100049, China.,Department of Biomedical Engineering, Electrical and Computer Engineering, Photonics Center, Boston University , Boston, Massachusetts 02215, United States
| | - Delong Zhang
- Department of Biomedical Engineering, Electrical and Computer Engineering, Photonics Center, Boston University , Boston, Massachusetts 02215, United States
| | - Chen Li
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
| | - Cheng Liu
- National Laboratory on High Power Laser and Physics , Shanghai 201800, China.,Key Laboratory of High Power Laser and Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences , Shanghai 201800, China
| | - Ji-Xin Cheng
- Department of Biomedical Engineering, Electrical and Computer Engineering, Photonics Center, Boston University , Boston, Massachusetts 02215, United States
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19
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Wei S, Kulkarni P, Ashley K, Zheng L. Measurement of Crystalline Silica Aerosol Using Quantum Cascade Laser-Based Infrared Spectroscopy. Sci Rep 2017; 7:13860. [PMID: 29066770 PMCID: PMC5654752 DOI: 10.1038/s41598-017-14363-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 10/10/2017] [Indexed: 11/09/2022] Open
Abstract
Inhalation exposure to airborne respirable crystalline silica (RCS) poses major health risks in many industrial environments. There is a need for new sensitive instruments and methods for in-field or near real-time measurement of crystalline silica aerosol. The objective of this study was to develop an approach, using quantum cascade laser (QCL)-based infrared spectroscopy (IR), to quantify airborne concentrations of RCS. Three sampling methods were investigated for their potential for effective coupling with QCL-based transmittance measurements: (i) conventional aerosol filter collection, (ii) focused spot sample collection directly from the aerosol phase, and (iii) dried spot obtained from deposition of liquid suspensions. Spectral analysis methods were developed to obtain IR spectra from the collected particulate samples in the range 750-1030 cm-1. The new instrument was calibrated and the results were compared with standardized methods based on Fourier transform infrared (FTIR) spectrometry. Results show that significantly lower detection limits for RCS (≈330 ng), compared to conventional infrared methods, could be achieved with effective microconcentration and careful coupling of the particulate sample with the QCL beam. These results offer promise for further development of sensitive filter-based laboratory methods and portable sensors for near real-time measurement of crystalline silica aerosol.
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Affiliation(s)
- Shijun Wei
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Cincinnati, Ohio, 45226, USA.,University of Cincinnati, Department of Mechanical and Materials Engineering, Cincinnati, Ohio, 45221, USA
| | - Pramod Kulkarni
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Cincinnati, Ohio, 45226, USA.
| | - Kevin Ashley
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Cincinnati, Ohio, 45226, USA
| | - Lina Zheng
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Cincinnati, Ohio, 45226, USA
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20
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Tütüncü E, Kokoric V, Wilk A, Seichter F, Schmid M, Hunt WE, Manuel AM, Mirkarimi P, Alameda JB, Carter JC, Mizaikoff B. Fiber-Coupled Substrate-Integrated Hollow Waveguides: An Innovative Approach to Mid-infrared Remote Gas Sensors. ACS Sens 2017; 2:1287-1293. [PMID: 28792208 DOI: 10.1021/acssensors.7b00253] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, an innovative approach based on fiberoptically coupled substrate-integrated hollow waveguide (iHWG) gas cells for the analysis of low sample volumes suitable for remote broad- and narrow-band mid-infrared (MIR; 2.5-20 μm) sensing applications is reported. The feasibility of remotely addressing iHWG gas cells, configured in a double-pass geometry via a reflector, by direct coupling to a 7-around-1 mid-infrared fiber bundle is demonstrated, facilitating low-level hydrocarbon gas analysis. For comparison studies, two iHWGs with substrate dimensions of 50 × 50 × 12 mm (L × W × H) and geometric channel lengths of 138 and 58.5 mm, serving as miniature light-guiding gas cells, were fiber-coupled to a Fourier transform infrared spectrometer enabling broadband MIR sensing. In addition to the fundamental feasibility of this concept, the achievable sensitivity toward several gaseous hydrocarbons and the reproducibility of assembling the fiber-iHWG interface were investigated.
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Affiliation(s)
- Erhan Tütüncü
- Institute
of Analytical and Bioanalytical Chemistry (IABC), Ulm University, Albert-Einstein-Allee
11, 89081 Ulm, Germany
| | - Vjekoslav Kokoric
- Institute
of Analytical and Bioanalytical Chemistry (IABC), Ulm University, Albert-Einstein-Allee
11, 89081 Ulm, Germany
| | - Andreas Wilk
- Institute
of Analytical and Bioanalytical Chemistry (IABC), Ulm University, Albert-Einstein-Allee
11, 89081 Ulm, Germany
| | - Felicia Seichter
- Institute
of Analytical and Bioanalytical Chemistry (IABC), Ulm University, Albert-Einstein-Allee
11, 89081 Ulm, Germany
| | - Michael Schmid
- Institute
of Analytical and Bioanalytical Chemistry (IABC), Ulm University, Albert-Einstein-Allee
11, 89081 Ulm, Germany
| | - William E. Hunt
- Lawrence Livermore National Laboratory (LLNL), 7000 East Avenue, Livermore, California 94550, United States
| | - Anastacia M. Manuel
- Lawrence Livermore National Laboratory (LLNL), 7000 East Avenue, Livermore, California 94550, United States
| | - Paul Mirkarimi
- Lawrence Livermore National Laboratory (LLNL), 7000 East Avenue, Livermore, California 94550, United States
| | - Jennifer B. Alameda
- Lawrence Livermore National Laboratory (LLNL), 7000 East Avenue, Livermore, California 94550, United States
| | - J. Chance Carter
- Lawrence Livermore National Laboratory (LLNL), 7000 East Avenue, Livermore, California 94550, United States
| | - Boris Mizaikoff
- Institute
of Analytical and Bioanalytical Chemistry (IABC), Ulm University, Albert-Einstein-Allee
11, 89081 Ulm, Germany
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21
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Schwaighofer A, Brandstetter M, Lendl B. Quantum cascade lasers (QCLs) in biomedical spectroscopy. Chem Soc Rev 2017; 46:5903-5924. [DOI: 10.1039/c7cs00403f] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
This review focuses on the recent applications of QCLs in mid-IR spectroscopy of clinically relevant samples.
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Affiliation(s)
- Andreas Schwaighofer
- Institute of Chemical Technologies and Analytics
- Vienna University of Technology
- 1060 Vienna
- Austria
| | | | - Bernhard Lendl
- Institute of Chemical Technologies and Analytics
- Vienna University of Technology
- 1060 Vienna
- Austria
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22
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Seichter F, Vogt J, Radermacher P, Mizaikoff B. Nonlinear calibration transfer based on hierarchical Bayesian models and Lagrange Multipliers: Error bounds of estimates via Monte Carlo – Markov Chain sampling. Anal Chim Acta 2017; 951:32-45. [DOI: 10.1016/j.aca.2016.11.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 09/09/2016] [Accepted: 11/09/2016] [Indexed: 10/20/2022]
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23
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Brumfield BE, Phillips MC. Quantitative isotopic measurements of gas-phase alcohol mixtures using a broadly tunable swept external cavity quantum cascade laser. Analyst 2017; 142:2354-2362. [PMID: 28573273 DOI: 10.1039/c7an00223h] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Isotopic quantification of gas-phase mixtures is performed using a swept external cavity quantum cascade laser and broadband infrared spectral analysis.
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24
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Wang L, Zhang J, Jia Z, Zhao Y, Liu C, Liu Y, Zhai S, Ning Z, Xu X, Liu F. Phase-locked array of quantum cascade lasers with an integrated Talbot cavity. OPTICS EXPRESS 2016; 24:30275-30281. [PMID: 28059303 DOI: 10.1364/oe.24.030275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We show a phase-locked array of three quantum cascade lasers with an integrated Talbot cavity at one side of the laser array. The coupling scheme is called diffraction coupling. By controlling the length of Talbot to be a quarter of Talbot distance (Zt/4), in-phase mode operation can be selected. The in-phase operation shows great modal stability under different injection currents, from the threshold current to the full power current. The far-field radiation pattern of the in-phase operation contains three lobes, one central maximum lobe and two side lobes. The interval between adjacent lobes is about 10.5°. The output power is about 1.5 times that of a single-ridge laser. Further studies should be taken to achieve better beam performance and reduce optical losses brought by the integrated Talbot cavity.
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25
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Adamu AI, Ozturk FE, Bayindir M. Binary coded identification of industrial chemical vapors with an optofluidic nose. APPLIED OPTICS 2016; 55:10247-10254. [PMID: 28059241 DOI: 10.1364/ao.55.010247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
An artificial nose system for the recognition and classification of gas-phase analytes and its application in identifying common industrial gases is reported. The sensing mechanism of the device comprises the measurement of infrared absorption of volatile analytes inside the hollow cores of optofluidic Bragg fibers. An array of six fibers is used, where each fiber targets a different region of the mid-infrared in the range of 2-14 μm with transmission bandwidths of about 1-3 μm. The quenching in the transmission of each fiber due to the presence of analyte molecules in the hollow core is measured separately and the cross response of the array allows the identification of virtually any volatile organic compound (VOC). The device was used for the identification of seven industrial VOC vapors with high selectivity using a standard blackbody source and an infrared detector. The array response is registered as a unique six digit binary code for each analyte by assigning a threshold value to the fiber transmissions. The developed prototype is a comprehensive and versatile artificial nose that is applicable to a wide range of analytes.
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26
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Schädle T, Mizaikoff B. Mid-Infrared Waveguides: A Perspective. APPLIED SPECTROSCOPY 2016; 70:1625-1638. [PMID: 27624555 DOI: 10.1177/0003702816659668] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 05/10/2016] [Indexed: 05/28/2023]
Abstract
Significant advancements in waveguide technology in the mid-infrared (MIR) regime during recent decades have assisted in establishing MIR spectroscopic and sensing technologies as a routine tool among nondestructive analytical methods. In this review, the evolution of MIR waveguides along with state-of-the-art technologies facilitating next-generation MIR chem/bio sensors will be discussed introducing a classification scheme defining three "generations" of MIR waveguides: (1) conventional internal reflection elements as "first generation" waveguides; (2) MIR-transparent optical fibers as "second generation" waveguides; and most recently introduced(3) thin-film structures as "third generation" waveguides. Selected application examples for these each waveguide category along with future trends will highlight utility and perspectives for waveguide-based MIR spectroscopy and sensing systems.
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Affiliation(s)
- Thomas Schädle
- Institute of Analytical and Bioanalytical Chemistry (IABC), Ulm University, Ulm, Germany
| | - Boris Mizaikoff
- Institute of Analytical and Bioanalytical Chemistry (IABC), Ulm University, Ulm, Germany
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27
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Galán-Freyle NJ, Pacheco-Londoño LC, Román-Ospino AD, Hernandez-Rivera SP. Applications of Quantum Cascade Laser Spectroscopy in the Analysis of Pharmaceutical Formulations. APPLIED SPECTROSCOPY 2016; 70:1511-1519. [PMID: 27558366 DOI: 10.1177/0003702816662609] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 03/07/2016] [Indexed: 06/06/2023]
Abstract
Quantum cascade laser spectroscopy was used to quantify active pharmaceutical ingredient content in a model formulation. The analyses were conducted in non-contact mode by mid-infrared diffuse reflectance. Measurements were carried out at a distance of 15 cm, covering the spectral range 1000-1600 cm(-1) Calibrations were generated by applying multivariate analysis using partial least squares models. Among the figures of merit of the proposed methodology are the high analytical sensitivity equivalent to 0.05% active pharmaceutical ingredient in the formulation, high repeatability (2.7%), high reproducibility (5.4%), and low limit of detection (1%). The relatively high power of the quantum-cascade-laser-based spectroscopic system resulted in the design of detection and quantification methodologies for pharmaceutical applications with high accuracy and precision that are comparable to those of methodologies based on near-infrared spectroscopy, attenuated total reflection mid-infrared Fourier transform infrared spectroscopy, and Raman spectroscopy.
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Affiliation(s)
- Nataly J Galán-Freyle
- ALERT DHS Center of Excellence for Explosives Research, Department of Chemistry, University of Puerto Rico, USA School of Basic and Biomedical Sciences, Universidad Simón Bolívar, Barranquilla, Colombia
| | - Leonardo C Pacheco-Londoño
- ALERT DHS Center of Excellence for Explosives Research, Department of Chemistry, University of Puerto Rico, USA Environmental Engineering Program, Vice-Rectory for Research, ECCI University, Bogotá, D.C., Colombia
| | | | - Samuel P Hernandez-Rivera
- ALERT DHS Center of Excellence for Explosives Research, Department of Chemistry, University of Puerto Rico, USA
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28
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Rapid and Sensitive Quantification of Isotopic Mixtures Using a Rapidly-Swept External Cavity Quantum Cascade Laser. PHOTONICS 2016. [DOI: 10.3390/photonics3020033] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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29
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Recent Advances and Applications of External Cavity-QCLs towards Hyperspectral Imaging for Standoff Detection and Real-Time Spectroscopic Sensing of Chemicals. PHOTONICS 2016. [DOI: 10.3390/photonics3020028] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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30
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Techniques and issues in breath and clinical sample headspace analysis for disease diagnosis. Bioanalysis 2016; 8:677-90. [PMID: 26978667 DOI: 10.4155/bio.16.22] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Analysis of volatile organic compounds (VOCs) from breath or clinical samples for disease diagnosis is an attractive proposition because it is noninvasive and rapid. There are numerous studies showing its potential, yet there are barriers to its development. Sampling and sample handling is difficult, and when coupled with a variety of analytical instrumentation, the same samples can give different results. Background air and the environment a person has been exposed to can greatly affect the VOCs emitted by the body; however, this is not an easy problem to solve. This review investigates the use of VOCs in disease diagnosis, the analytical techniques employed and the problems associated with sample handling and standardization. It then suggests the barriers to future development.
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31
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Kokoric V, Widmann D, Wittmann M, Behm RJ, Mizaikoff B. Infrared spectroscopy via substrate-integrated hollow waveguides: a powerful tool in catalysis research. Analyst 2016; 141:5990-5995. [DOI: 10.1039/c6an01534d] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Monitoring catalyst performance via substrate-integrated hollow waveguide (iHWGs) assisted infrared spectroscopy.
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Affiliation(s)
- V. Kokoric
- Institute of Analytical and Bioanalytical Chemistry
- Ulm University
- 89081 Ulm
- Germany
| | - D. Widmann
- Institute of Surface Chemistry and Catalysis
- Ulm University
- 89069 Ulm
- Germany
| | - M. Wittmann
- Institute of Surface Chemistry and Catalysis
- Ulm University
- 89069 Ulm
- Germany
| | - R. J. Behm
- Institute of Surface Chemistry and Catalysis
- Ulm University
- 89069 Ulm
- Germany
| | - B. Mizaikoff
- Institute of Analytical and Bioanalytical Chemistry
- Ulm University
- 89081 Ulm
- Germany
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32
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Tütüncü E, Kokoric V, Szedlak R, MacFarland D, Zederbauer T, Detz H, Andrews AM, Schrenk W, Strasser G, Mizaikoff B. Advanced gas sensors based on substrate-integrated hollow waveguides and dual-color ring quantum cascade lasers. Analyst 2016; 141:6202-6207. [DOI: 10.1039/c6an01130f] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first combination of a ring-shaped vertically emitting quantum cascade laser (riQCL) with a substrate-integrated hollow waveguide (iHWG) is presented.
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Affiliation(s)
- Erhan Tütüncü
- Institute of Analytical and Bioanalytical Chemistry
- Ulm University
- Germany
| | - Vjekoslav Kokoric
- Institute of Analytical and Bioanalytical Chemistry
- Ulm University
- Germany
| | - Rolf Szedlak
- Institute of Solid State Electronics
- TU Wien
- Austria
| | | | | | | | | | | | - Gottfried Strasser
- Institute of Solid State Electronics
- TU Wien
- Austria
- Center for Micro- and Nanostructures
- TU Wien
| | - Boris Mizaikoff
- Institute of Analytical and Bioanalytical Chemistry
- Ulm University
- Germany
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33
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Brumfield BE, Taubman MS, Suter JD, Phillips MC. Characterization of a swept external cavity quantum cascade laser for rapid broadband spectroscopy and sensing. OPTICS EXPRESS 2015; 23:25553-25569. [PMID: 26480072 DOI: 10.1364/oe.23.025553] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The performance of a rapidly swept external cavity quantum cascade laser (ECQCL) system combined with an open-path Herriott cell was evaluated for time-resolved measurements of chemical species with broad and narrow absorption spectra. A spectral window spanning 1278 - 1390 cm(-1) was acquired at a 200 Hz acquisition rate, corresponding to a tuning rate of 2x10(4) cm(-1)/s, with a spectral resolution of 0.2 cm(-1). The capability of the ECQCL to measure < 100 ppbv changes in nitrous oxide (N(2)O) and 1,1,1,2-tetrafluoroethane (F134A) concentrations on millisecond timescales was demonstrated in simulated plume studies with releases near the open-path Herriott cell. Absorbance spectra measured using the ECQCL system exhibited noise-equivalent absorption coefficients of 5x10(-9) cm(-1)Hz(-1/2). For a spectrum acquisition time of 5 ms, noise-equivalent concentrations (NEC) for N(2)O and F134A were measured to be 70 and 16 ppbv respectively, which improved to sub-ppbv levels with averaging to 100 s. Noise equivalent column densities of 0.64 and 0.25 ppmv × m in 1 sec are estimated for N(2)O and F134A.
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34
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Bird B, Baker MJ. Quantum Cascade Lasers in Biomedical Infrared Imaging. Trends Biotechnol 2015; 33:557-558. [DOI: 10.1016/j.tibtech.2015.07.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Revised: 06/19/2015] [Accepted: 07/22/2015] [Indexed: 10/23/2022]
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35
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Zaharov VV, Farahi RH, Snyder PJ, Davison BH, Passian A. Karhunen-Loève treatment to remove noise and facilitate data analysis in sensing, spectroscopy and other applications. Analyst 2015; 139:5927-35. [PMID: 25252650 DOI: 10.1039/c4an01300j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Resolving weak spectral variations in the dynamic response of materials that are either dominated or excited by stochastic processes remains a challenge. Responses that are thermal in origin are particularly relevant examples due to the delocalized nature of heat. Despite its inherent properties in dealing with stochastic processes, the Karhunen-Loève expansion has not been fully exploited in measurement of systems that are driven solely by random forces or can exhibit large thermally driven random fluctuations. Here, we present experimental results and analysis of the archetypes (a) the resonant excitation and transient response of an atomic force microscope probe by the ambient random fluctuations and nanoscale photothermal sample response, and (b) the photothermally scattered photons in pump-probe spectroscopy. In each case, the dynamic process is represented as an infinite series with random coefficients to obtain pertinent frequency shifts and spectral peaks and demonstrate spectral enhancement for a set of compounds including the spectrally complex biomass. The considered cases find important applications in nanoscale material characterization, biosensing, and spectral identification of biological and chemical agents.
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Affiliation(s)
- V V Zaharov
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6123, USA.
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Perez-Guaita D, Kokoric V, Wilk A, Garrigues S, Mizaikoff B. Towards the determination of isoprene in human breath using substrate-integrated hollow waveguide mid-infrared sensors. J Breath Res 2014; 8:026003. [PMID: 24848160 DOI: 10.1088/1752-7155/8/2/026003] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Selected volatile organic compounds (VOCs) in breath may be considered biomarkers if they are indicative of distinct diseases or disease states. Given the inherent molecular selectivity of vibrational spectroscopy, infrared sensing technologies appear ideally suitable for the determination of endogenous VOCs in breath. The aim of this study was to determine that mid-infrared (MIR; 3-20 µm) gas phase sensing is capable of determining isoprene in exhaled breath as an exemplary medically relevant VOC by hyphenating novel substrate-integrated hollow waveguides (iHWG) with a likewise miniaturized preconcentration system. A compact preconcentrator column for sampling isoprene from exhaled breath was coupled to an iHWG serving simultaneously as highly miniaturized gas cell and light conduit in combination with a compact Fourier transform infrared spectrometer. A gas mixing system enabled extensive system calibration using isoprene standards. After system optimization, a calibration function obtaining a limit of quantification of 106 ppb was achieved. According to the literature, the obtained sensitivity is sufficient for quantifying middle to high isoprene concentrations occurring in exhaled breath. Finally, a volunteer breath sample was analysed proving comparable values of isoprene in a real-world scenario. Despite its fundamental utility, the proposed methodology contains some limitations in terms of sensitivity and temporal resolution in comparison with the readily available measurement techniques that should be addressed during future optimization of the system. Nonetheless, this study presents the first determination of endogenous VOCs in breath via advanced hollow waveguide MIR sensor technology, clearly demonstrating its potential for the analysis of volatile biomarkers in exhaled breath.
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Affiliation(s)
- David Perez-Guaita
- Analytical Chemistry Department, University of Valencia, EdificiJeroni Muñoz, Burjassot, Spain
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Abstract
Despite providing the opportunity for directly sensing molecular constituents with inherent fingerprint specificity in the 2.5-20 μm spectral regime, mid-infrared optical sensing technologies have not yet achieved the same penetration in waveguide-based chem/bio sensing compared to related sensing schemes operating at visible and near-infrared frequencies. In this review, current advances in mid-infrared chem/bio sensor technology will be highlighted and contrasted with the prevalent bottlenecks that have to date limited a more widespread adoption of mid-infrared sensing devices. However, with the increasing availability of advanced light sources such as quantum cascade lasers and the advent of on-chip semiconductor waveguide technologies, a prosperous future of this sensing concept for label-free detection in environmental analysis, process monitoring, and bioanalytics is perceived.
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Affiliation(s)
- Boris Mizaikoff
- Institute of Analytical and Bioanalytical Chemistry, University of Ulm, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
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Petruci JFDS, Fortes PR, Kokoric V, Wilk A, Raimundo IM, Cardoso AA, Mizaikoff B. Monitoring of hydrogen sulfide via substrate-integrated hollow waveguide mid-infrared sensors in real-time. Analyst 2014; 139:198-203. [PMID: 24256718 DOI: 10.1039/c3an01793a] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Hydrogen sulfide is a highly corrosive, harmful, and toxic gas produced under anaerobic conditions within industrial processes or in natural environments, and plays an important role in the sulfur cycle. According to the U.S. Occupational Safety and Health Administration (OSHA), the permissible exposure limit (during 8 hours) is 10 ppm. Concentrations of 20 ppm are the threshold for critical health issues. In workplace environments with human subjects frequently exposed to H2S, e.g., during petroleum extraction and refining, real-time monitoring of exposure levels is mandatory. Sensors based on electrochemical measurement principles, semiconducting metal-oxides, taking advantage of their optical properties, have been described for H2S monitoring. However, extended response times, limited selectivity, and bulkiness of the instrumentation are common disadvantages of the sensing techniques reported to date. Here, we describe for the first time usage of a new generation of compact gas cells, i.e., so-called substrate-integrated hollow waveguides (iHWGs), combined with a compact Fourier transform infrared (FTIR) spectrometer for advanced gas sensing of H2S. The principle of detection is based on the immediate UV-assisted conversion of the rather weak IR-absorber H2S into much more pronounced and distinctively responding SO2. A calibration was established in the range of 10-100 ppm with a limit of detection (LOD) at 3 ppm, which is suitable for occupational health monitoring purposes. The developed sensing scheme provides an analytical response time of less than 60 seconds. Considering the substantial potential for miniaturization using e.g., a dedicated quantum cascade laser (QCL) in lieu of the FTIR spectrometer, the developed sensing approach may be evolved into a hand-held instrument, which may be tailored to a variety of applications ranging from environmental monitoring to workplace safety surveillance, process analysis and clinical diagnostics, e.g., breath analysis.
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Phillips MC, Taubman MS, Bernacki BE, Cannon BD, Stahl RD, Schiffern JT, Myers TL. Real-time trace gas sensing of fluorocarbons using a swept-wavelength external cavity quantum cascade laser. Analyst 2014; 139:2047-56. [DOI: 10.1039/c3an01642k] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Zhang L, Tian G, Li J, Yu B. Applications of absorption spectroscopy using quantum cascade lasers. APPLIED SPECTROSCOPY 2014; 68:1095-1107. [PMID: 25239063 DOI: 10.1366/14-00001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Infrared laser absorption spectroscopy (LAS) is a promising modern technique for sensing trace gases with high sensitivity, selectivity, and high time resolution. Mid-infrared quantum cascade lasers, operating in a pulsed or continuous wave mode, have potential as spectroscopic sources because of their narrow linewidths, single mode operation, tunability, high output power, reliability, low power consumption, and compactness. This paper reviews some important developments in modern laser absorption spectroscopy based on the use of quantum cascade laser (QCL) sources. Among the various laser spectroscopic methods, this review is focused on selected absorption spectroscopy applications of QCLs, with particular emphasis on molecular spectroscopy, industrial process control, combustion diagnostics, and medical breath analysis.
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Affiliation(s)
- Lizhu Zhang
- School of Science, Tianjin University of Technology and Education, Tianjin 300220, China
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da Silveira Petruci JF, Fortes PR, Kokoric V, Wilk A, Raimundo IM, Cardoso AA, Mizaikoff B. Real-time monitoring of ozone in air using substrate-integrated hollow waveguide mid-infrared sensors. Sci Rep 2013; 3:3174. [PMID: 24213678 PMCID: PMC4070560 DOI: 10.1038/srep03174] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 10/15/2013] [Indexed: 11/10/2022] Open
Abstract
Ozone is a strong oxidant that is globally used as disinfection agent for many purposes including indoor building air cleaning, during food preparation procedures, and for control and killing of bacteria such as E. coli and S. aureus. However, it has been shown that effective ozone concentrations for controlling e.g., microbial growth need to be higher than 5 ppm, thereby exceeding the recommended U.S. EPA threshold more than 10 times. Consequently, real-time monitoring of such ozone concentration levels is essential. Here, we describe the first online gas sensing system combining a compact Fourier transform infrared (FTIR) spectrometer with a new generation of gas cells, a so-called substrate-integrated hollow waveguide (iHWG). The sensor was calibrated using an UV lamp for the controlled generation of ozone in synthetic air. A calibration function was established in the concentration range of 0.3-5.4 mmol m⁻³ enabling a calculated limit of detection (LOD) at 0.14 mmol m⁻³ (3.5 ppm) of ozone. Given the adaptability of the developed IR sensing device toward a series of relevant air pollutants, and considering the potential for miniaturization e.g., in combination with tunable quantum cascade lasers in lieu of the FTIR spectrometer, a wide range of sensing and monitoring applications of beyond ozone analysis are anticipated.
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Affiliation(s)
- João Flávio da Silveira Petruci
- São Paulo State University, Department of Analytical Chemistry, UNESP, CEP 14800–970, Araraquara, SP, Brazil
- University of Ulm, Institute of Analytical and Bioanalytical Chemistry, 89081, Ulm, Germany
| | - Paula Regina Fortes
- University of Ulm, Institute of Analytical and Bioanalytical Chemistry, 89081, Ulm, Germany
- University of Campinas, Department of Analytical Chemistry, UNICAMP, Campinas, SP, Brazil
| | - Vjekoslav Kokoric
- University of Ulm, Institute of Analytical and Bioanalytical Chemistry, 89081, Ulm, Germany
| | - Andreas Wilk
- University of Ulm, Institute of Analytical and Bioanalytical Chemistry, 89081, Ulm, Germany
| | - Ivo Milton Raimundo
- University of Campinas, Department of Analytical Chemistry, UNICAMP, Campinas, SP, Brazil
| | - Arnaldo Alves Cardoso
- São Paulo State University, Department of Analytical Chemistry, UNESP, CEP 14800–970, Araraquara, SP, Brazil
| | - Boris Mizaikoff
- University of Ulm, Institute of Analytical and Bioanalytical Chemistry, 89081, Ulm, Germany
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Wilk A, Carter JC, Chrisp M, Manuel AM, Mirkarimi P, Alameda JB, Mizaikoff B. Substrate-Integrated Hollow Waveguides: A New Level of Integration in Mid-Infrared Gas Sensing. Anal Chem 2013; 85:11205-10. [DOI: 10.1021/ac402391m] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Andreas Wilk
- Institute
of Analytical and Bioanalytical Chemistry (IABC), University of Ulm, Albert-Einstein-Allee
11, 89081 Ulm, Germany
| | - J. Chance Carter
- Lawrence
Livermore National Laboratory (LLNL), 7000 East Avenue, Livermore California 94550, United States
| | - Michael Chrisp
- Lawrence
Livermore National Laboratory (LLNL), 7000 East Avenue, Livermore California 94550, United States
| | - Anastacia M. Manuel
- Lawrence
Livermore National Laboratory (LLNL), 7000 East Avenue, Livermore California 94550, United States
| | - Paul Mirkarimi
- Lawrence
Livermore National Laboratory (LLNL), 7000 East Avenue, Livermore California 94550, United States
| | - Jennifer B. Alameda
- Lawrence
Livermore National Laboratory (LLNL), 7000 East Avenue, Livermore California 94550, United States
| | - Boris Mizaikoff
- Institute
of Analytical and Bioanalytical Chemistry (IABC), University of Ulm, Albert-Einstein-Allee
11, 89081 Ulm, Germany
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Improving the performance of hollow waveguide-based infrared gas sensors via tailored chemometrics. Anal Bioanal Chem 2013; 405:8223-32. [DOI: 10.1007/s00216-013-7230-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 06/21/2013] [Accepted: 07/08/2013] [Indexed: 11/25/2022]
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