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Merian A, Silva A, Wolf S, Frosch T, Frosch T. Ultrasensitive Raman Gas Spectroscopy for Dinitrogen Sensing at the Parts-per-Billion Level. Anal Chem 2024. [PMID: 39231523 DOI: 10.1021/acs.analchem.4c02828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2024]
Abstract
Sensing small changes in the concentration of dinitrogen (N2) is a difficult analytical task. As N2-sensing is crucial for nitrogen cycle research in general and studies of denitrification in particular, researchers went to great lengths to develop techniques like the gas-flow-soil-core method, which achieves a precision of 200 ppb at 20 ppm of N2. Here, we present a Raman gas spectroscopic technique based on high pressure, high laser power, and high-NA signal collection, which achieves a limit of detection (LoD) of 59 ppb N2 and a precision of 27 ppb at 10 ppm of N2. This improves the lowest LoD for N2 reported for Raman gas spectroscopy by 2 orders of magnitude. Furthermore, this constitutes an improvement in precision by 1 order of magnitude compared to the GC-MS-based gas-flow-soil-core method currently established in denitrification research. We show that the presented setup is both stable and tight enough to ensure highly sensitive, precise, and repeatable measurements of N2. As Raman gas spectroscopy is a versatile and comprehensive method, the described technique could be easily expanded to other relevant gases like nitrous oxide or to simultaneous multigas sensing. In summary, our method offers possibilities for N2-sensing and could eventually enable denitrification studies with increased sensitivity and a larger scope.
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Affiliation(s)
- Andreas Merian
- Biophotonics and Biomedical Engineering Group, Technical University Darmstadt, Merckstr. 25, 64283 Darmstadt, Germany
| | - Artur Silva
- Biophotonics and Biomedical Engineering Group, Technical University Darmstadt, Merckstr. 25, 64283 Darmstadt, Germany
| | - Sebastian Wolf
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Timea Frosch
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Torsten Frosch
- Biophotonics and Biomedical Engineering Group, Technical University Darmstadt, Merckstr. 25, 64283 Darmstadt, Germany
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
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2
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Blohm A, Domes C, Merian A, Wolf S, Popp J, Frosch T. Comprehensive multi-gas study by means of fiber-enhanced Raman spectroscopy for the investigation of nitrogen cycle processes. Analyst 2024; 149:1885-1894. [PMID: 38357795 DOI: 10.1039/d4an00023d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
The extensive use of synthetic fertilizers has led to a considerable increase in reactive nitrogen input into agricultural and natural systems, resulting in negative effects in multiple ecosystems, the so-called nitrogen cascade. Since the global population relies on fertilization for food production, synthetic fertilizer use needs to be optimized by balancing crop yield and reactive nitrogen losses. Fiber-enhanced Raman spectroscopy (FERS) is introduced as a unique method for the simultaneous quantification of multiple gases to the study processes related to the nitrogen cycle. By monitoring changes in the headspace gas concentrations, processes such as denitrification, nitrification, respiration, and nitrogen fixation, as well as fertilizer addition were studied. The differences in concentration between the ambient and prepared process samples were evident in the Raman spectra, allowing for differentiation of process-specific spectra. Gas mixture concentrations were quantified within a range of low ppm to 100% for the gases N2, O2, CO2, N2O, and NH3. Compositional changes were attributed to processes of the nitrogen cycle. With help of multivariate curve resolution, it was possible to quantify N2O and CO2 simultaneously. The impact of fertilizers on N-cycle processes in soil was simulated and analyzed for identifying active processes. Thus, FERS was proven to be a suitable technique to optimize fertilizer composition and to quantify N2O and NH3 emissions, all with a single device and without further sample preparation.
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Affiliation(s)
- Annika Blohm
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Christian Domes
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Andreas Merian
- Biophotonics and Biomedical Engineering Group, Technical University Darmstadt, Merckstraße 25, 64283 Darmstadt, Germany.
| | - Sebastian Wolf
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
- Abbe Centre of Photonics, Friedrich Schiller University, 07743 Jena, Germany
| | - Torsten Frosch
- Biophotonics and Biomedical Engineering Group, Technical University Darmstadt, Merckstraße 25, 64283 Darmstadt, Germany.
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
- Abbe Centre of Photonics, Friedrich Schiller University, 07743 Jena, Germany
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3
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Ge H, Kong W, Wang R, Zhao G, Ma W, Chen W, Wan F. Simple technique of coupling a diode laser into a linear power buildup cavity for Raman gas sensing. OPTICS LETTERS 2023; 48:2186-2189. [PMID: 37058673 DOI: 10.1364/ol.486417] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 03/19/2023] [Indexed: 06/19/2023]
Abstract
We report a novel, to the best of our knowledge, and simple technique to lock a 642 nm multi-quantum well diode laser to an external linear power buildup cavity by directly feeding the cavity reflected light back to the diode laser for enhancement of gas Raman signals. The dominance of the resonant light field in the locking process is achieved by reducing the reflectivity of the cavity input mirror and thus making the intensity of the directly reflected light weaker than that of the resonant light. Compared with traditional techniques, stable power buildup in the fundamental transverse mode TEM00 is guaranteed without any additional optical elements or complex optical arrangements. An intracavity exciting light of 160 W is generated with a 40 mW diode laser. Using a backward Raman light collection geometry, detection limits at the ppm level are achieved for ambient gases (N2, O2) with an exposure time of 60 s.
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4
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Liu B, Liu K, Sun J, Shang L, Yang Q, Chen X, Li B. Classification of pathogenic bacteria by Raman spectroscopy combined with variational auto-encoder and deep learning. JOURNAL OF BIOPHOTONICS 2023; 16:e202200270. [PMID: 36519533 DOI: 10.1002/jbio.202200270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 12/06/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
Rapid and early identification of pathogens is critical to guide antibiotic therapy. Raman spectroscopy as a noninvasive diagnostic technique provides rapid and accurate detection of pathogens. Raman spectrum of single cells serves as the "fingerprint" of the cell, revealing its metabolic characteristics. Rapid identification of pathogens can be achieved by combining Raman spectroscopy and deep learning. Traditional classification techniques frequently require lots of data for training, which is time costing to collect Raman spectra. For trace samples and strains that are difficult to culture, it is difficult to provide an accurate classification model. In order to reduce the number of samples collected and improve the accuracy of the classification model, a new pathogen detection method integrating Raman spectroscopy, variational auto-encoder (VAE), and long short-term memory network (LSTM) is proposed in this paper. We collect the Raman signals of pathogens and input them to VAE for training. VAE will generate a large number of Raman spectral data that cannot be distinguished from the real spectrum, and the signal-to-noise ratio is higher than that of the real spectrum. These spectra are input into the LSTM together with the real spectrum for training, and a good classification model is obtained. The results of the experiments reveal that this method not only improves the average accuracy of pathogen classification to 96.9% but also reduces the number of Raman spectra collected from 1000 to 200. With this technology, the number of Raman spectra collected can be greatly reduced, so that strains that are difficult to culture or trace can be rapidly identified.
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Affiliation(s)
- Bo Liu
- State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Kunxiang Liu
- State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Jide Sun
- Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Lindong Shang
- State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Qingxiang Yang
- Department of Laboratory Medicine, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Xueping Chen
- The Center for Clinical Molecular Medical detection, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Bei Li
- State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, China
- University of Chinese Academy of Sciences, Beijing, China
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5
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Liu B, Liu K, Qi X, Zhang W, Li B. Classification of deep-sea cold seep bacteria by transformer combined with Raman spectroscopy. Sci Rep 2023; 13:3240. [PMID: 36828824 PMCID: PMC9958026 DOI: 10.1038/s41598-023-28730-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 01/24/2023] [Indexed: 02/26/2023] Open
Abstract
Raman spectroscopy is a rapid analysis method of biological samples without labeling and destruction. At present, the commonly used Raman spectrum classification models include CNN, RNN, etc. The transformer has not been used for Raman spectrum identification. This paper introduces a new method of transformer combined with Raman spectroscopy to identify deep-sea cold seep microorganisms at the single-cell level. We collected the Raman spectra of eight cold seep bacteria, each of which has at least 500 spectra for the training of transformer model. We compare the transformer classification model with other deep learning classification models. The experimental results show that this method can improve the accuracy of microbial classification. Our average isolation level accuracy is more than 97%.
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Affiliation(s)
- Bo Liu
- State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Kunxiang Liu
- State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, People's Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Xiaoqing Qi
- Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000, Hainan, China
| | - Weijia Zhang
- Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000, Hainan, China.
| | - Bei Li
- State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, People's Republic of China.
- University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
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6
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Li F, Zhao Q, Sun C, Zhu L, Xia J, Huang B. Probing natural gas components with Raman integrating sphere technology. OPTICS LETTERS 2023; 48:187-190. [PMID: 36638414 DOI: 10.1364/ol.474494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 12/05/2022] [Indexed: 06/17/2023]
Abstract
Raman spectroscopy is a powerful method of probing natural gas components, but higher sensitivity, greater miniaturization, and lower cost techniques are required. Therefore, we designed a Raman integrating sphere-enhanced spectroscopy technology in a volume of 40 × 40 × 20 cm3 based on the principle of integrating sphere reflection. This technology consists of two parts: the first is an integrating sphere model to collect scattered signals, and the second is a right-angle light-boosting system to increase the optical path of the pump light in the sample. Raman integrating sphere technology has a detection limit of 0.5 ppm in the air with an exposure time of 600 s under room temperature and ambient pressure conditions. Experiments of natural gas detection display that the detection limits of ethane, propane, n-butane, isobutane, n-pentane, and isopentane are 28, 28, 95, 28, 189, and 95 ppm, respectively. In addition, there is a linear relationship between the relative Raman intensity and the concentration of each component in natural gas, which can be used as a probe for detecting unknown natural gas components in gas wells.
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7
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Wang P, Chen W, Wang J, Zhou F, Hu J, Zhang Z, Wan F. Hazardous Gas Detection by Cavity-Enhanced Raman Spectroscopy for Environmental Safety Monitoring. Anal Chem 2021; 93:15474-15481. [PMID: 34775758 DOI: 10.1021/acs.analchem.1c03499] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We demonstrate the practicability of cavity-enhanced Raman spectroscopy (CERS) with a folded multipass cavity as a unique tool for the detection of hazardous gases in the atmosphere. A four-mirror Z-sharped multipass cavity results in a greatly extended laser-gas interaction length to improve the Raman signal intensity of gases. For Raman intensity maximization, the optimal number of intracavity beams of a single reflection cycle is calculated and then the cavity parameters are designed. A total of 360 intracavity beams are realized, which are circulated four times in the cavity based on the polarization. ppb-Level Raman gas sensing at atmospheric pressure for several typical explosive gases and toxic gases in ambient air, including hydrogen (H2), methane (CH4), carbon monoxide (CO), hydrogen sulfide (H2S), and chlorine (Cl2), is achieved at 300 s exposure time. Our CERS apparatus, which can detect multiple gases simultaneously with ultrahigh sensitivity and high selectivity, is powerful for detecting hazardous gases in the atmosphere, and it has excellent potential for environmental safety monitoring.
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Affiliation(s)
- Pinyi Wang
- Chongqing University State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing 400044, China
| | - Weigen Chen
- Chongqing University State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing 400044, China
| | - Jianxin Wang
- Chongqing University State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing 400044, China
| | - Feng Zhou
- Chongqing University State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing 400044, China.,State Grid Jiangsu Electric Power Company Changzhou Power Supply Company, Jiangsu, Nanjing 213000, China
| | - Jin Hu
- Chongqing University State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing 400044, China.,Electric Power Research Institute of Yunnan Power Grid Company Limited, Yunnan, Kunming 650217, China
| | - Zhixian Zhang
- Chongqing University State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing 400044, China
| | - Fu Wan
- Chongqing University State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing 400044, China
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8
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Blohm A, Kumar S, Knebl A, Herrmann M, Küsel K, Popp J, Frosch T. Activity and electron donor preference of two denitrifying bacterial strains identified by Raman gas spectroscopy. Anal Bioanal Chem 2021; 414:601-611. [PMID: 34297136 PMCID: PMC8748363 DOI: 10.1007/s00216-021-03541-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 07/06/2021] [Accepted: 07/08/2021] [Indexed: 11/26/2022]
Abstract
Human activities have greatly increased the input of reactive nitrogen species into the environment and disturbed the balance of the global N cycle. This imbalance may be offset by bacterial denitrification, an important process in maintaining the ecological balance of nitrogen. However, our understanding of the activity of mixotrophic denitrifying bacteria is not complete, as most research has focused on heterotrophic denitrification. The aim of this study was to investigate substrate preferences for two mixotrophic denitrifying bacterial strains, Acidovorax delafieldii and Hydrogenophaga taeniospiralis, under heterotrophic, autotrophic or mixotrophic conditions. This complex analysis was achieved by simultaneous identification and quantification of H2, O2, CO2, 14N2, 15N2 and 15N2O in course of the denitrification process with help of cavity-enhanced Raman spectroscopic (CERS) multi-gas analysis. To disentangle electron donor preferences for both bacterial strains, microcosm-based incubation experiments under varying substrate conditions were conducted. We found that Acidovorax delafieldii preferentially performed heterotrophic denitrification in the mixotrophic sub-experiments, while Hydrogenophaga taeniospiralis preferred autotrophic denitrification in the mixotrophic incubation. These observations were supported by stoichiometric calculations. The results demonstrate the prowess of advanced Raman multi-gas analysis to study substrate use and electron donor preferences in denitrification, based on the comprehensive quantification of complex microbial gas exchange processes.
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Affiliation(s)
- Annika Blohm
- Leibniz Institute of Photonic Technology, 07745, Jena, Germany
| | - Swatantar Kumar
- Institute of Biodiversity, Friedrich Schiller University Jena, 07743, Jena, Germany
| | - Andreas Knebl
- Leibniz Institute of Photonic Technology, 07745, Jena, Germany
| | - Martina Herrmann
- Institute of Biodiversity, Friedrich Schiller University Jena, 07743, Jena, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103, Leipzig, Germany
| | - Kirsten Küsel
- Institute of Biodiversity, Friedrich Schiller University Jena, 07743, Jena, Germany
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103, Leipzig, Germany
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology, 07745, Jena, Germany
- Institute of Physical Chemistry, Friedrich Schiller University Jena, 07743, Jena, Germany
- Abbe Centre of Photonics, Friedrich Schiller University, 07743, Jena, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology, 07745, Jena, Germany.
- Institute of Physical Chemistry, Friedrich Schiller University Jena, 07743, Jena, Germany.
- Abbe Centre of Photonics, Friedrich Schiller University, 07743, Jena, Germany.
- Biophotonics and Biomedical Engineering Group, Technical University Darmstadt, Merckstraße 25, 64283, Darmstadt, Germany.
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9
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Potthast K, Meyer S, Tischer A, Gleixner G, Sieburg A, Frosch T, Michalzik B. Grasshopper herbivory immediately affects element cycling but not export rates in an N‐limited grassland system. Ecosphere 2021. [DOI: 10.1002/ecs2.3449] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Karin Potthast
- Institute of Geography/Chair of Soil Science Friedrich Schiller University Jena Löbdergraben 32 Jena07743Germany
| | - Stefanie Meyer
- Medical Center LMU Munich Ziemssenstraße 1 Munchen80336Germany
| | - Alexander Tischer
- Institute of Geography/Chair of Soil Science Friedrich Schiller University Jena Löbdergraben 32 Jena07743Germany
| | - Gerd Gleixner
- Research Group of Molecular Biogeochemistry MPI for Biogeochemistry Hans‐Knöll‐Straße 10 Jena07745Germany
| | - Anne Sieburg
- Leibniz Institute of Photonic Technology Jena07745Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology Jena07745Germany
- Institute of Physical Chemistry and Abbe Centre of Photonics Friedrich Schiller University Jena Jena07745Germany
| | - Beate Michalzik
- Institute of Geography/Chair of Soil Science Friedrich Schiller University Jena Löbdergraben 32 Jena07743Germany
- German Center for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Leipzig Germany
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10
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Maity A, Maithani S, Pradhan M. Cavity Ring-Down Spectroscopy: Recent Technological Advancements, Techniques, and Applications. Anal Chem 2020; 93:388-416. [DOI: 10.1021/acs.analchem.0c04329] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Abhijit Maity
- 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
| | - 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
| | - 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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11
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Knebl A, Domes R, Wolf S, Domes C, Popp J, Frosch T. Fiber-Enhanced Raman Gas Spectroscopy for the Study of Microbial Methanogenesis. Anal Chem 2020; 92:12564-12571. [PMID: 32845132 DOI: 10.1021/acs.analchem.0c02507] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Microbial methanogenesis is a key biogeochemical process in the carbon cycle that is responsible for 70% of global emissions of the potent greenhouse gas methane (CH4). Further knowledge about microbial methanogenesis is crucial to mitigate emissions, increase climate model accuracy, or advance methanogenic biogas production. The current understanding of the substrate use of methanogenic microbes is limited, especially regarding the methylotrophic pathway. Here, we present fiber-enhanced Raman spectroscopy (FERS) of headspace gases as an alternate tool to study methanogenesis and substrate use in particular. The optical technique is nondestructive and sensitive to CH4, hydrogen (H2), and carbon dioxide with a large dynamic range from trace levels (demonstrated LoDs: CH4, 3 ppm; H2, 49 ppm) to pure gases. In addition, the portable FERS system can provide quantitative information about methanol concentration in the liquid phase of microbial cultures through headspace gas sampling (LoD 25 ppm). We demonstrate how FERS gas sensing could enable us to track substrate and product levels of microbial methanogenesis with just one instrument. The versatility of Raman gas spectroscopy could moreover help us to elucidate links between nitrogen and carbon cycle in microbial communities in the near future.
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Affiliation(s)
- Andreas Knebl
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Robert Domes
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Sebastian Wolf
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Christian Domes
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Juergen Popp
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany.,Friedrich Schiller University, Institute of Physical Chemistry, 07743 Jena, Germany.,Friedrich Schiller University, Abbe Center of Photonics, 07745 Jena, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany.,Friedrich Schiller University, Institute of Physical Chemistry, 07743 Jena, Germany.,Friedrich Schiller University, Abbe Center of Photonics, 07745 Jena, Germany
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12
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Rapid Raman Spectroscopic Analysis of Stress Induced Degradation of the Pharmaceutical Drug Tetracycline. Molecules 2020; 25:molecules25081866. [PMID: 32316681 PMCID: PMC7221697 DOI: 10.3390/molecules25081866] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/07/2020] [Accepted: 04/08/2020] [Indexed: 12/14/2022] Open
Abstract
Stress factors caused by inadequate storage can induce the unwanted degradation of active compounds in pharmaceutical formulations. Resonance Raman spectroscopy is presented as an analytical tool for rapid monitoring of small concentration changes of tetracycline and the metabolite 4˗epianhydrotetracycline. These degradation processes were experimentally induced by changes in temperature, humidity, and irradiation with visible light over a time period of up to 23 days. The excitation wavelength λexc = 413 nm was proven to provide short acquisition times for the simultaneous Raman spectroscopic detection of the degradation of tetracycline and production of its impurity in small sample volumes. Small concentration changes could be detected (down to 1.4% for tetracycline and 0.3% for 4-epianhydrotetracycline), which shows the potential of resonance Raman spectroscopy for analyzing the decomposition of pharmaceutical products.
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13
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Petrov DV, Kostenko MA, Shcherbakov AA. Silver holographic gratings as substrates for surface-enhanced Raman scattering gas analysis. APPLIED OPTICS 2020; 59:2929-2934. [PMID: 32225843 DOI: 10.1364/ao.386897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 02/21/2020] [Indexed: 06/10/2023]
Abstract
This work is devoted to the investigation of the enhancement of Raman signals of nonadsorbed gases in the vicinity of corrugated metallic surfaces supporting propagating surface plasmon-polaritons (PSPPs). Simulation of the PSPP excitation efficiency on holographic gratings coated with silver films of various thicknesses at different groove heights was carried out. Verification showed good agreement between theory and experiment. Also, it was found that an increase of the PSPP excitation efficiency may not lead to an increase in the enhancement factor of Raman signals of gases located near the surface-enhanced Raman scattering active surface. For a holographic grating with a period of 667 nm, a groove height of 70 nm, and a silver film thickness of 30 nm coated with a protective ${{\rm Al}_2}{{\rm O}_3}$Al2O3 layer, the enhancement factor of Raman signals of nonadsorbed nitrogen molecules was $\sim{{\rm 4\cdot10}^3}$∼4⋅103.
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14
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Wolf S, Frosch T, Popp J, Pletz MW, Frosch T. Highly Sensitive Detection of the Antibiotic Ciprofloxacin by Means of Fiber Enhanced Raman Spectroscopy. Molecules 2019; 24:molecules24244512. [PMID: 31835489 PMCID: PMC6943513 DOI: 10.3390/molecules24244512] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 12/05/2019] [Accepted: 12/06/2019] [Indexed: 12/13/2022] Open
Abstract
Sepsis and septic shock exhibit a rapid course and a high fatality rate. Antibiotic treatment is time-critical and precise knowledge of the antibiotic concentration during the patients’ treatment would allow individual dose adaption. Over- and underdosing will increase the antimicrobial efficacy and reduce toxicity. We demonstrated that fiber enhanced Raman spectroscopy (FERS) can be used to detect very low concentrations of ciprofloxacin in clinically relevant doses, down to 1.5 µM. Fiber enhancement was achieved in bandgap shifted photonic crystal fibers. The high linearity between the Raman signals and the drug concentrations allows a robust calibration for drug quantification. The needed sample volume was very low (0.58 µL) and an acquisition time of 30 s allowed the rapid monitoring of ciprofloxacin levels in a less invasive way than conventional techniques. These results demonstrate that FERS has a high potential for clinical in-situ monitoring of ciprofloxacin levels.
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Affiliation(s)
- Sebastian Wolf
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Timea Frosch
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Juergen Popp
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
- Institute of Physical Chemistry, Friedrich Schiller University, 07743 Jena, Germany
- Abbe Center of Photonics, Friedrich Schiller University, 07745 Jena, Germany
| | - Mathias W. Pletz
- Institute of Infectious Diseases and Infection Control, University Hospital, 07747 Jena, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
- Institute of Physical Chemistry, Friedrich Schiller University, 07743 Jena, Germany
- Abbe Center of Photonics, Friedrich Schiller University, 07745 Jena, Germany
- Correspondence: or
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15
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Frosch T, Wyrwich E, Yan D, Popp J, Frosch T. Fiber-Array-Based Raman Hyperspectral Imaging for Simultaneous, Chemically-Selective Monitoring of Particle Size and Shape of Active Ingredients in Analgesic Tablets. Molecules 2019; 24:E4381. [PMID: 31801249 PMCID: PMC6930444 DOI: 10.3390/molecules24234381] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 11/17/2019] [Accepted: 11/28/2019] [Indexed: 11/20/2022] Open
Abstract
The particle shape, size and distribution of active pharmaceutical ingredients (API) are relevant quality indicators of pharmaceutical tablets due to their high impact on the manufacturing process. Furthermore, the bioavailability of the APIs from the dosage form depends largely on these characteristics. Routinely, particle size and shape are only analyzed in the powder form, without regard to the effect of the formulation procedure on the particle characteristics. The monitoring of these parameters improves the understanding of the process; therefore, higher quality and better control over the biopharmaceutical profile can be ensured. A new fiber-array-based Raman hyperspectral imaging technique is presented for direct simultaneous in-situ monitoring of three different active pharmaceutical ingredients- acetylsalicylic acid, acetaminophen and caffeine- in analgesic tablets. This novel method enables a chemically selective, noninvasive assessment of the distribution of the active ingredients down to 1 µm spatial resolution. The occurrence of spherical and needle-like particles, as well as agglomerations and the respective particle size ranges, were rapidly determined for two commercially available analgesic tablet types. Subtle differences were observed in comparison between these two tablets. Higher amounts of acetaminophen were visible, more needle-shaped and bigger acetylsalicylic acid particles, and a higher incidence of bigger agglomerations were found in one of the analgesic tablets.
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Affiliation(s)
- Timea Frosch
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany; (T.F.); (E.W.); (D.Y.); (J.P.)
| | - Elisabeth Wyrwich
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany; (T.F.); (E.W.); (D.Y.); (J.P.)
| | - Di Yan
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany; (T.F.); (E.W.); (D.Y.); (J.P.)
| | - Juergen Popp
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany; (T.F.); (E.W.); (D.Y.); (J.P.)
- Institute of Physical Chemistry, Friedrich Schiller University, 07743 Jena, Germany
- Abbe Centre of Photonics, Friedrich Schiller University, 07745 code Jena, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany; (T.F.); (E.W.); (D.Y.); (J.P.)
- Institute of Physical Chemistry, Friedrich Schiller University, 07743 Jena, Germany
- Abbe Centre of Photonics, Friedrich Schiller University, 07745 code Jena, Germany
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16
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Wang P, Chen W, Wan F, Wang J, Hu J. Cavity-enhanced Raman spectroscopy with optical feedback frequency-locking for gas sensing. OPTICS EXPRESS 2019; 27:33312-33325. [PMID: 31878402 DOI: 10.1364/oe.27.033312] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 10/09/2019] [Indexed: 06/10/2023]
Abstract
A cavity-enhanced Raman spectroscopy (CERS) gas-sensing method is introduced. Using optical feedback frequency-locking, laser radiation provided by a diode laser is coupled into a three-mirror V-shaped optical cavity. An intracavity laser power of 92 W is realized, yielding a power gain factor of 2200. Raman spectrums of air, carbon dioxide, and acetylene are recorded as a demonstration. Multicomponent gas mixtures including isotopic gases can be simultaneously sensed by CERS. With 200 s exposure time, detection limits of 5.35 Pa for N2, 5.07 Pa for O2, 1.74 Pa for CO2, and 0.58 Pa for C2H2 are achieved. CERS is a powerful gas-sensing method with high selectivity and sensitivity, which also has the potential for quantitative analysis of gases with high accuracy.
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17
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Sieburg A, Knebl A, Jacob JM, Frosch T. Characterization of fuel gases with fiber-enhanced Raman spectroscopy. Anal Bioanal Chem 2019; 411:7399-7408. [DOI: 10.1007/s00216-019-02145-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 08/19/2019] [Accepted: 09/06/2019] [Indexed: 12/15/2022]
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18
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Frosch T, Wyrwich E, Yan D, Domes C, Domes R, Popp J, Frosch T. Counterfeit and Substandard Test of the Antimalarial Tablet Riamet ® by Means of Raman Hyperspectral Multicomponent Analysis. Molecules 2019; 24:molecules24183229. [PMID: 31491881 PMCID: PMC6767462 DOI: 10.3390/molecules24183229] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 08/31/2019] [Accepted: 09/02/2019] [Indexed: 02/06/2023] Open
Abstract
The fight against counterfeit pharmaceuticals is a global issue of utmost importance, as failed medication results in millions of deaths every year. Particularly affected are antimalarial tablets. A very important issue is the identification of substandard tablets that do not contain the nominal amounts of the active pharmaceutical ingredient (API), and the differentiation between genuine products and products without any active ingredient or with a false active ingredient. This work presents a novel approach based on fiber-array based Raman hyperspectral imaging to qualify and quantify the antimalarial APIs lumefantrine and artemether directly and non-invasively in a tablet in a time-efficient way. The investigations were carried out with the antimalarial tablet Riamet® and self-made model tablets, which were used as examples of counterfeits and substandard. Partial least-squares regression modeling and density functional theory calculations were carried out for quantification of lumefantrine and artemether and for spectral band assignment. The most prominent differentiating vibrational signatures of the APIs were presented.
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Affiliation(s)
- Timea Frosch
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | | | - Di Yan
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Christian Domes
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Robert Domes
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Juergen Popp
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
- Friedrich Schiller University, Institute of Physical Chemistry, 07745 Jena, Germany
- Friedrich Schiller University, Abbe Centre of Photonics, 07745 Jena, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany.
- Friedrich Schiller University, Institute of Physical Chemistry, 07745 Jena, Germany.
- Friedrich Schiller University, Abbe Centre of Photonics, 07745 Jena, Germany.
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19
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Petrov DV, Matrosov II, Zaripov AR, Maznoy AS. Effects of pressure and composition on Raman spectra of CO-H 2-CO 2-CH 4 mixtures. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2019; 215:363-370. [PMID: 30852284 DOI: 10.1016/j.saa.2019.03.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 02/26/2019] [Accepted: 03/03/2019] [Indexed: 06/09/2023]
Abstract
There is great interest in the development of renewable and environmentally friendly fuel sources such as biogas and syngas for generation of heat and electricity. Raman spectroscopy is a promising method for rapid quantitative analysis of the composition of such gases. To improve the accuracy of the method, information is needed on changes in the spectra of the main components as a function of pressure and gas composition. In this work the spectral characteristics of the most intense peaks of methane, carbon monoxide, carbon dioxide and hydrogen in the range of 200-3800 cm-1 were investigated in the range of 1-25 bar for pure gases and binary mixtures. It has been revealed that, under these conditions, the change in the characteristics of pure rotational hydrogen lines is negligible, while the Q-branches of the main vibrational bands of methane, carbon monoxide and carbon dioxide shift to a few tenths of cm-1. The values of errors that can occur in the case of ignoring such changes in the spectra are estimated.
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Affiliation(s)
- D V Petrov
- Institute of Monitoring of Climatic and Ecological Systems, 10/3 Academicheskiy ave., 634055 Tomsk, Russia; Tomsk State University, 36 Lenina ave., 634050 Tomsk, Russia.
| | - I I Matrosov
- Institute of Monitoring of Climatic and Ecological Systems, 10/3 Academicheskiy ave., 634055 Tomsk, Russia
| | - A R Zaripov
- Institute of Monitoring of Climatic and Ecological Systems, 10/3 Academicheskiy ave., 634055 Tomsk, Russia
| | - A S Maznoy
- Tomsk Scientific Center, 10/4 Academicheskiy ave., 634055 Tomsk, Russia
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20
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Knebl A, Domes R, Yan D, Popp J, Trumbore S, Frosch T. Fiber-Enhanced Raman Gas Spectroscopy for 18O- 13C-Labeling Experiments. Anal Chem 2019; 91:7562-7569. [PMID: 31050402 DOI: 10.1021/acs.analchem.8b05684] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Stable isotopes are used in ecology to track and disentangle different processes and pathways. Especially for studies focused on the gas exchange of plants, sensing techniques that offer oxygen (O2) and carbon dioxide (CO2) sensitivity with isotopic discrimination are highly sought after. Addressing this challenge, fiber-enhanced Raman gas spectroscopy is introduced as a fast optical technique directly combining 13CO2 and 12CO2 as well as 18O2 and 16O2 measurements in one instrument. We demonstrate how a new type of optical hollow-core fiber, the so-called revolver fiber, is utilized for enhanced Raman gas sensing. Carbon dioxide and oxygen isotopologues were measured at concentrations expected when using 13C- and 18O-labeled gases in plant experiments. Limits of detection have been determined to be 25 ppm for CO2 and 150 ppm for O2. The combination of measurements with different integration times allows the creation of highly resolved broadband spectra. With the help of calculations based on density functional theory, the line at 1512 cm-1 occurring in the oxygen spectrum is assigned to 18O16O. The relative abundances of the isotopologues 18O16O and nitrogen 15N14N were in good agreement with typical values. For CO2, fiber-enhanced Raman spectra show the Fermi diad and hotbands of 12C16O2, 13C16O2, and 12C18O16O. Several weak lines were observed, and the line at 1426 cm-1 was identified as originating from the (0 4 0 2) → (0 2 0 2) transition of 12C16O2. With the demonstrated sensitivity and discriminatory power, fiber-enhanced Raman spectroscopy is a possible alternative means to investigate plant metabolism, directly combining 13CO2 and 12CO2 measurements with 18O2 and 16O2 measurements in one instrument. The presented method thus has large potential for basic analytical investigations as well as for applications in the environmental sciences.
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Affiliation(s)
- Andreas Knebl
- Leibniz Institute of Photonic Technology , 07745 Jena , Germany.,Max-Planck-Institute for Biogeochemistry , 07745 Jena , Germany
| | - Robert Domes
- Leibniz Institute of Photonic Technology , 07745 Jena , Germany
| | - Di Yan
- Leibniz Institute of Photonic Technology , 07745 Jena , Germany
| | - Juergen Popp
- Leibniz Institute of Photonic Technology , 07745 Jena , Germany.,Institute of Physical Chemistry & Abbe Center of Photonics , Friedrich Schiller University , 07743 Jena , Germany
| | - Susan Trumbore
- Max-Planck-Institute for Biogeochemistry , 07745 Jena , Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology , 07745 Jena , Germany.,Institute of Physical Chemistry & Abbe Center of Photonics , Friedrich Schiller University , 07743 Jena , Germany
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21
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Yan D, Frosch T, Kobelke J, Bierlich J, Popp J, Pletz MW, Frosch T. Fiber-Enhanced Raman Sensing of Cefuroxime in Human Urine. Anal Chem 2018; 90:13243-13248. [PMID: 30387601 DOI: 10.1021/acs.analchem.8b01355] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Fiber-enhanced Raman spectroscopy was developed for the chemically selective and sensitive quantification of the important antibiotic cefuroxime in human urine. A novel optical sensor fiber was drawn and precisely prepared. In this fiber structure, light is strongly confined in the selectively filled liquid core, and the Raman scattered signal is collected with unprecedented efficiency over an extended interaction length. The filling, emptying, and robustness are highly improved due to the large core size (>30 μm). Broadband step-index guidance allows the free choice of the most suitable excitation wavelength in complex body fluids. The limit of detection of cefuroxime in human urine was improved by 2 orders of magnitude (to μM level). The quantification of cefuroxime was achieved in urine after oral administration. This method has great potential for the point-of-care monitoring of antibiotics concentrations and is an important step forward to enable clinicians to rapidly adjust doses.
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Affiliation(s)
- Di Yan
- Leibniz Institute of Photonic Technology , Jena 07745 , Germany
| | - Timea Frosch
- Leibniz Institute of Photonic Technology , Jena 07745 , Germany
| | - Jens Kobelke
- Leibniz Institute of Photonic Technology , Jena 07745 , Germany
| | - Jörg Bierlich
- Leibniz Institute of Photonic Technology , Jena 07745 , Germany
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology , Jena 07745 , Germany.,Friedrich Schiller University , Institute of Physical Chemistry , Jena 07743 , Germany.,Friedrich Schiller University , Abbe Centre of Photonics , Jena 07745 , Germany
| | - Mathias W Pletz
- Center for Infectious Diseases and Infection Control , Jena University Hospital , Jena 07740 , Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology , Jena 07745 , Germany.,Friedrich Schiller University , Institute of Physical Chemistry , Jena 07743 , Germany.,Friedrich Schiller University , Abbe Centre of Photonics , Jena 07745 , Germany
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22
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Sieburg A, Jochum T, Trumbore SE, Popp J, Frosch T. Onsite cavity enhanced Raman spectrometry for the investigation of gas exchange processes in the Earth's critical zone. Analyst 2018; 142:3360-3369. [PMID: 28853462 DOI: 10.1039/c7an01149k] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Raman gas spectrometry is introduced as a robust, versatile method for onsite, battery-powered field measurements of gases in the unsaturated and saturated critical zone. In this study, depth-profiles of the concentrations of oxygen and carbon dioxide were simultaneously monitored down to ∼70 meters depth in the subsurface via a transect of drilling holes located in the Hainich Critical Zone Exploratory in central Germany. A special multichannel monitoring system was designed to access and analyze these gases non-consumptively onsite in a closed loop measurement cycle. During the timeframe of six months, seasonal changes in groundwater levels and microbial activity were related to changes observed in gas concentrations. High oxygen concentrations were found in the depths surrounding a karstified aquifer complex, while low oxygen concentrations were found in a fractured aquifer complex. Raman gas depth-profiles complement standard dissolved oxygen measurements as they also deliver oxygen concentrations in the unsaturated zone. The measured depth-profiles of the gas concentrations indicated that regions of anoxia can exist between the aquifer complexes. Lateral transport of O2 in the deeper aquifer complex provides a local source of O2 that can influence metabolism. Correlations were found between the observed CO2 concentrations and pH-values, indicating strong control of carbonate equilibria. The concentrations of O2 and CO2 were largely decoupled, thus simultaneous measurements of O2 soil effluxes give additional insights into biotic and abiotic processes in the Hainich CZE. These results illustrate the versatility of robust onsite Raman multigas measurements of the soil atmosphere and how they can contribute to the analysis of complex processes in previous uncharacterized environments in the critical zone.
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Affiliation(s)
- Anne Sieburg
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany.
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23
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Kumar S, Herrmann M, Blohm A, Hilke I, Frosch T, Trumbore SE, Küsel K. Thiosulfate- and hydrogen-driven autotrophic denitrification by a microbial consortium enriched from groundwater of an oligotrophic limestone aquifer. FEMS Microbiol Ecol 2018; 94:5056153. [DOI: 10.1093/femsec/fiy141] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 07/18/2018] [Indexed: 01/17/2023] Open
Affiliation(s)
- Swatantar Kumar
- Aquatic Geomicrobiology, Institute of Biodiversity, Friedrich Schiller University Jena, Dornburger Strasse 159, D-07743 Jena, Germany
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Strasse 10, D-07745 Jena, Germany
| | - Martina Herrmann
- Aquatic Geomicrobiology, Institute of Biodiversity, Friedrich Schiller University Jena, Dornburger Strasse 159, D-07743 Jena, Germany
- German Center for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, D-04103 Leipzig, Germany
| | - Annika Blohm
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Strasse 10, D-07745 Jena, Germany
- Leibniz Institute of Photonic Technology, Albert-Einstein-Strasse 9, D-07745 Jena, Germany
| | - Ines Hilke
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Strasse 10, D-07745 Jena, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology, Albert-Einstein-Strasse 9, D-07745 Jena, Germany
- Institute of Physical Chemistry and Abbe Center of Photonics, Albert-Einstein-Strasse 6, D-07745, Jena, Germany
| | - Susan E Trumbore
- Max Planck Institute for Biogeochemistry, Hans-Knöll-Strasse 10, D-07745 Jena, Germany
| | - Kirsten Küsel
- Aquatic Geomicrobiology, Institute of Biodiversity, Friedrich Schiller University Jena, Dornburger Strasse 159, D-07743 Jena, Germany
- German Center for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, D-04103 Leipzig, Germany
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24
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25
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Zhao Y, Yamaguchi Y, Liu C, Sekine S, Dou X. Quantitative Detection of Ethanol/Acetone in Complex Solutions Using Raman Spectroscopy Based on Headspace Gas Analysis. APPLIED SPECTROSCOPY 2018; 72:280-287. [PMID: 29082758 DOI: 10.1177/0003702817738010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
This paper demonstrated the quantitative detection of ethanol and acetone mixtures in complex solutions with Raman spectroscopy based on headspace gas analysis. By analyzing the volatile components in the headspace, their concentrations in liquid solutions were determined. We constructed our own Raman spectroscopy system to detect the headspace gas quantitatively over a solution in a sealed vial. The Raman spectra of the headspace gases over standard solutions were standardized for finding the concentrations of ethanol, acetone, and ethanol-acetone in mixture solutions. The results showed that the concentration of a gaseous component in the headspace gas was proportional to its ratio in the liquid solution. We obtained a linear relationship between the spectral intensity of volatile components in headspace and the concentration of the liquid solutions. Then, we analyzed the alcohol concentration in a white wine and a Chinese liquor called Fen Chiew by measuring the Raman spectra of the headspace gas over their liquids. For the river water sample, we also implemented our headspace gas detection with Raman spectra to obtain the concentration of acetone in the river sample. This work demonstrated the facilitation of headspace gas analysis by the qualitative and quantitative determination of volatile substances from liquid samples using Raman spectroscopy.
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Affiliation(s)
- Yubin Zhao
- 1 Institute of Photonics & Bio-medicine, Graduate School of Science, East China University of Science and Technology, Shanghai, China
| | - Yoshinori Yamaguchi
- 1 Institute of Photonics & Bio-medicine, Graduate School of Science, East China University of Science and Technology, Shanghai, China
- 2 Department of Applied Physics, Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Chenchen Liu
- 1 Institute of Photonics & Bio-medicine, Graduate School of Science, East China University of Science and Technology, Shanghai, China
| | - Shinichi Sekine
- 3 Preventive Dentistry, Osaka University Dental Hospital, Osaka University, Osaka, Japan
| | - Xiaoming Dou
- 1 Institute of Photonics & Bio-medicine, Graduate School of Science, East China University of Science and Technology, Shanghai, China
- 2 Department of Applied Physics, Graduate School of Engineering, Osaka University, Osaka, Japan
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26
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Sieburg A, Schneider S, Yan D, Popp J, Frosch T. Monitoring of gas composition in a laboratory biogas plant using cavity enhanced Raman spectroscopy. Analyst 2018; 143:1358-1366. [DOI: 10.1039/c7an01689a] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cavity-enhanced Raman spectroscopy is a powerful tool for online detection of multiple gases during the process of biogas production.
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Affiliation(s)
- Anne Sieburg
- Leibniz Institute of Photonic Technology
- 07745 Jena
- Germany
| | | | - Di Yan
- Leibniz Institute of Photonic Technology
- 07745 Jena
- Germany
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology
- 07745 Jena
- Germany
- Friedrich Schiller University
- Institute of Physical Chemistry
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology
- 07745 Jena
- Germany
- Friedrich Schiller University
- Institute of Physical Chemistry
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27
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Yan D, Popp J, Frosch T. Analysis of Fiber-Enhanced Raman Gas Sensing Based on Raman Chemical Imaging. Anal Chem 2017; 89:12269-12275. [DOI: 10.1021/acs.analchem.7b03209] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Di Yan
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
- Friedrich Schiller University, Institute of Physical
Chemistry, 07743 Jena, Germany
- Friedrich Schiller University, Abbe Center of Photonics, 07745 Jena, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany
- Friedrich Schiller University, Institute of Physical
Chemistry, 07743 Jena, Germany
- Friedrich Schiller University, Abbe Center of Photonics, 07745 Jena, Germany
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28
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Domes C, Domes R, Popp J, Pletz MW, Frosch T. Ultrasensitive Detection of Antiseptic Antibiotics in Aqueous Media and Human Urine Using Deep UV Resonance Raman Spectroscopy. Anal Chem 2017; 89:9997-10003. [PMID: 28840713 DOI: 10.1021/acs.analchem.7b02422] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Deep UV resonance Raman spectroscopy is introduced as an analytical tool for ultrasensitive analysis of antibiotics used for empirical treatment of patients with sepsis and septic shock, that is, moxifloxacin, meropenem, and piperacillin in aqueous solution and human urine. By employing the resonant excitation wavelengths λexc = 244 nm and λexc = 257 nm, only a small sample volume and short acquisition times are needed. For a better characterization of the matrix urine, the main ingredients were investigated. The capability of detecting the antibiotics in clinically relevant concentrations in aqueous media (LODs: 13.0 ± 1.4 μM for moxifloxacin, 43.6 ± 10.7 μM for meropenem, and 7.1 ± 0.6 μM for piperacillin) and in urine (LODs: 36.6 ± 11.0 μM for moxifloxacin, and 114.8 ± 3.1 μM for piperacillin) points toward the potential of UV Raman spectroscopy as point-of-care method for therapeutic drug monitoring (TDM). This procedure enables physicians to achieve fast adequate dosing of antibiotics to improve the outcome of patients with sepsis.
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Affiliation(s)
- Christian Domes
- Leibniz Institute of Photonic Technology , Jena 07745, Germany
| | - Robert Domes
- Leibniz Institute of Photonic Technology , Jena 07745, Germany
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology , Jena 07745, Germany.,Friedrich Schiller University , Institute for Physical Chemistry, Jena 07743, Germany.,Friedrich Schiller University , Abbe Centre of Photonics, Jena 07745, Germany
| | - Mathias W Pletz
- Center for Infectious Diseases and Infection Control, Jena University Hospital , Jena 07743, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology , Jena 07745, Germany.,Friedrich Schiller University , Institute for Physical Chemistry, Jena 07743, Germany.,Friedrich Schiller University , Abbe Centre of Photonics, Jena 07745, Germany
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29
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Smith TW, Hippler M. Cavity-Enhanced Raman Spectroscopy in the Biosciences: In Situ, Multicomponent, and Isotope Selective Gas Measurements To Study Hydrogen Production and Consumption by Escherichia coli. Anal Chem 2017; 89:2147-2154. [PMID: 28105804 DOI: 10.1021/acs.analchem.6b04924] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Recently we introduced cavity-enhanced Raman spectroscopy (CERS) with optical feedback cw-diode lasers as a sensitive analytical tool. Here we report improvements made on the technique and its first application in the biosciences for in situ, multicomponent, and isotope selective gas measurements to study hydrogen production and consumption by Escherichia coli. Under anaerobic conditions, cultures grown on rich media supplemented with d-glucose or glycerol produce H2 and simultaneously consume some of it. By introducing D2 in the headspace, hydrogen production and consumption could be separated due to the distinct spectroscopic signatures of isotopomers. Different phases with distinctly different kinetic regimes of H2 and CO2 production and D2 consumption were identified. Some of the D2 consumed is converted back to H2 via H/D exchange with the solvent. HD was formed only as a minor component. This reflects either that H/D exchange at hydrogenase active sites is rapid compared to the rate of recombination, rapid recapture of HD occurs after the molecule is formed, or that the active sites where D2 oxidation and proton reduction occur are physically separated. Whereas in glucose supplemented cultures, addition of D2 led to an increase in H2 produced, while the yield of CO2 remained unchanged; with glycerol, addition of D2 led not only to increased yields of H2, but also significantly increased CO2 production, reflecting an impact on fermentation pathways. Addition of CO was found to completely inhibit H2 production and significantly reduce D2 oxidation, indicating at least some role for O2-tolerant Hyd-1 in D2 consumption.
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Affiliation(s)
- Thomas W Smith
- Department of Chemistry, University of Sheffield , Sheffield S3 7HF, United Kingdom
| | - Michael Hippler
- Department of Chemistry, University of Sheffield , Sheffield S3 7HF, United Kingdom
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30
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Jochum T, Rahal L, Suckert RJ, Popp J, Frosch T. All-in-one: a versatile gas sensor based on fiber enhanced Raman spectroscopy for monitoring postharvest fruit conservation and ripening. Analyst 2017; 141:2023-9. [PMID: 26882863 DOI: 10.1039/c5an02120k] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In today's fruit conservation rooms the ripening of harvested fruit is delayed by precise management of the interior oxygen (O2) and carbon dioxide (CO2) levels. Ethylene (C2H4), a natural plant hormone, is commonly used to trigger fruit ripening shortly before entering the market. Monitoring of these critical process gases, also of the increasingly favored cooling agent ammonia (NH3), is a crucial task in modern postharvest fruit management. The goal of this work was to develop and characterize a gas sensor setup based on fiber enhanced Raman spectroscopy for fast (time resolution of a few minutes) and non-destructive process gas monitoring throughout the complete postharvest production chain encompassing storage and transport in fruit conservation chambers as well as commercial fruit ripening in industrial ripening rooms. Exploiting a micro-structured hollow-core photonic crystal fiber for analyte gas confinement and sensitivity enhancement, the sensor features simultaneous quantification of O2, CO2, NH3 and C2H4 without cross-sensitivity in just one single measurement. Laboratory measurements of typical fruit conservation gas mixtures showed that the sensor is capable of quantifying O2 and CO2 concentration levels with accuracy of 3% or less with respect to reference concentrations. The sensor detected ammonia concentrations, relevant for chemical alarm purposes. Due to the high spectral resolution of the gas sensor, ethylene could be quantified simultaneously with O2 and CO2 in a multi-component mixture. These results indicate that fiber enhanced Raman sensors have a potential to become universally usable on-site gas sensors for controlled atmosphere applications in postharvest fruit management.
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Affiliation(s)
- Tobias Jochum
- Leibniz Institute of Photonic Technology, Jena, Germany
| | - Leila Rahal
- Leibniz Institute of Photonic Technology, Jena, Germany
| | | | - Jürgen Popp
- Leibniz Institute of Photonic Technology, Jena, Germany and Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University, Jena, Germany.
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology, Jena, Germany and Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University, Jena, Germany.
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31
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Domes R, Domes C, Albert CR, Bringmann G, Popp J, Frosch T. Vibrational spectroscopic characterization of arylisoquinolines by means of Raman spectroscopy and density functional theory calculations. Phys Chem Chem Phys 2017; 19:29918-29926. [DOI: 10.1039/c7cp05415g] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Seven new AIQ antimalarial agents were investigated using FT-NIR and deep-UV resonance Raman spectroscopy.
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Affiliation(s)
- Robert Domes
- Leibniz Institute of Photonic Technology
- Jena
- Germany
| | | | | | - Gerhard Bringmann
- Julius-Maximilians University
- Institute of Organic Chemistry
- Würzburg
- Germany
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology
- Jena
- Germany
- Friedrich Schiller University
- Institute for Physical Chemistry
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology
- Jena
- Germany
- Friedrich Schiller University
- Institute for Physical Chemistry
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32
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Jochum T, Fastnacht A, Trumbore SE, Popp J, Frosch T. Direct Raman Spectroscopic Measurements of Biological Nitrogen Fixation under Natural Conditions: An Analytical Approach for Studying Nitrogenase Activity. Anal Chem 2016; 89:1117-1122. [PMID: 28043118 DOI: 10.1021/acs.analchem.6b03101] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Biological N2 fixation is a major input of bioavailable nitrogen, which represents the most frequent factor limiting the agricultural production throughout the world. Especially, the symbiotic association between legumes and Rhizobium bacteria can provide substantial amounts of nitrogen (N) and reduce the need for industrial fertilizers. Despite its importance in the global N cycle, rates of biological nitrogen fixation have proven difficult to quantify. In this work, we propose and demonstrate a simple analytical approach to measure biological N2 fixation rates directly without a proxy or isotopic labeling. We determined a mean N2 fixation rate of 78 ± 5 μmol N2 (g dry weight nodule)-1 h-1 of a Medicago sativa-Rhizobium consortium by continuously analyzing the amount of atmospheric N2 in static environmental chambers with Raman gas spectroscopy. By simultaneously analyzing the CO2 uptake and photosynthetic plant activity, we think that a minimum CO2 mixing ratio might be needed for natural N2 fixation and only used the time interval above this minimum CO2 mixing ratio for N2 fixation rate calculations. The proposed approach relies only on noninvasive measurements of the gas phase and, given its simplicity, indicates the potential to estimate biological nitrogen fixation of legume symbioses not only in laboratory experiments. The same methods can presumably also be used to detect N2 fluxes by denitrification from ecosystems to the atmosphere.
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Affiliation(s)
- Tobias Jochum
- Leibniz Institute of Photonic Technology , 07745 Jena, Germany
| | - Agnes Fastnacht
- Max Planck Institute for Biogeochemistry , 07745 Jena, Germany
| | | | - Jürgen Popp
- Leibniz Institute of Photonic Technology , 07745 Jena, Germany.,Institute of Physical Chemistry and Abbe Center of Photonics , 07745 Jena, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology , 07745 Jena, Germany.,Institute of Physical Chemistry and Abbe Center of Photonics , 07745 Jena, Germany
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33
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Petrov DV. Multipass optical system for a Raman gas spectrometer. APPLIED OPTICS 2016; 55:9521-9525. [PMID: 27869865 DOI: 10.1364/ao.55.009521] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In the present work, a multipass optical system intended for increasing the sensitivity of a Raman gas spectrometer based on the 90° geometry of scattered light collection is described. The system is characterized by an adjustment stability and an increased number of laser beams that pass through a small scattering volume, thus allowing the intensities of Raman signals from components of the gas medium in this volume to be increased. It is demonstrated that the application of this multipass optical system allows the sensitivity of the Raman gas spectrometer to be increased practically by 20 times (to several ppm for the 30-s registration time).
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34
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Jochum T, von Fischer JC, Trumbore S, Popp J, Frosch T. Multigas Leakage Correction in Static Environmental Chambers Using Sulfur Hexafluoride and Raman Spectroscopy. Anal Chem 2015; 87:11137-42. [PMID: 26492154 DOI: 10.1021/acs.analchem.5b03312] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In static environmental chamber experiments, the precision of gas flux measurements can be significantly improved by a thorough gas leakage correction to avoid under- or overestimation of biological activity such as respiration or photosynthesis. Especially in the case of small biological net gas exchange rates or gas accumulation phases during long environmental monitoring experiments, gas leakage fluxes could distort the analysis of the biogenic gas kinetics. Here we propose and demonstrate a general protocol for online correction of diffusion-driven gas leakage in plant chambers by simultaneous quantification of the inert tracer sulfur hexafluoride (SF6) and the investigated biogenic gases using enhanced Raman spectroscopy. By quantifying the leakage rates of carbon dioxide (CO2), methane (CH4), and hydrogen (H2) simultaneously with SF6 in the test chamber, their effective diffusivity ratios of approximately 1.60, 1.96, and 5.65 were determined, each related to SF6. Because our experiments suggest that the effective diffusivity ratios are reproducible for an individual static environmental chamber, even under varying concentration gradients and slight changes of the chamber sealing, an experimental method to quantify gas leakage fluxes by using effective diffusivity ratios and SF6 leakage fluxes is proposed. The method is demonstrated by quantifying the CO2 net exchange rate of a plant-soil ecosystem (Mirabilis jalapa). By knowing the effective chamber diffusivity ratio CO2/SF6 and the measured SF6 leakage rate during the experiment, the leakage contribution to the total CO2 exchange rate could be calculated and the biological net CO2 concentration change within the chamber atmosphere determined.
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Affiliation(s)
- Tobias Jochum
- Leibniz Institute of Photonic Technology , Jena 07745, Germany
| | - Joseph C von Fischer
- Department of Biology and Graduate Degree Program in Ecology, Colorado State University , Fort Collins, Colorado 80523, United States
| | - Susan Trumbore
- Max Planck Institute for Biogeochemistry , Jena 07745, Germany
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology , Jena 07745, Germany.,Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University , Jena 07743, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology , Jena 07745, Germany.,Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University , Jena 07743, Germany
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Brückner M, Becker K, Popp J, Frosch T. Fiber array based hyperspectral Raman imaging for chemical selective analysis of malaria-infected red blood cells. Anal Chim Acta 2015; 894:76-84. [PMID: 26423630 DOI: 10.1016/j.aca.2015.08.025] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 08/08/2015] [Accepted: 08/13/2015] [Indexed: 10/23/2022]
Abstract
A new setup for Raman spectroscopic wide-field imaging is presented. It combines the advantages of a fiber array based spectral translator with a tailor-made laser illumination system for high-quality Raman chemical imaging of sensitive biological samples. The Gaussian-like intensity distribution of the illuminating laser beam is shaped by a square-core optical multimode fiber to a top-hat profile with very homogeneous intensity distribution to fulfill the conditions of Koehler. The 30 m long optical fiber and an additional vibrator efficiently destroy the polarization and coherence of the illuminating light. This homogeneous, incoherent illumination is an essential prerequisite for stable quantitative imaging of complex biological samples. The fiber array translates the two-dimensional lateral information of the Raman stray light into separated spectral channels with very high contrast. The Raman image can be correlated with a corresponding white light microscopic image of the sample. The new setup enables simultaneous quantification of all Raman spectra across the whole spatial area with very good spectral resolution and thus outperforms other Raman imaging approaches based on scanning and tunable filters. The unique capabilities of the setup for fast, gentle, sensitive, and selective chemical imaging of biological samples were applied for automated hemozoin analysis. A special algorithm was developed to generate Raman images based on the hemozoin distribution in red blood cells without any influence from other Raman scattering. The new imaging setup in combination with the robust algorithm provides a novel, elegant way for chemical selective analysis of the malaria pigment hemozoin in early ring stages of Plasmodium falciparum infected erythrocytes.
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Affiliation(s)
| | - Katja Becker
- Justus Liebig University Giessen, Biochemistry and Molecular Biology, 35392 Giessen, Germany
| | - Jürgen Popp
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany; Friedrich Schiller University Jena, Institute for Physical Chemistry, 07745 Jena, Germany; Friedrich Schiller University Jena, Abbe Centre of Photonics, 07745 Jena, Germany
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology, 07745 Jena, Germany; Friedrich Schiller University Jena, Institute for Physical Chemistry, 07745 Jena, Germany; Friedrich Schiller University Jena, Abbe Centre of Photonics, 07745 Jena, Germany.
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36
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Hanf S, Fischer S, Hartmann H, Keiner R, Trumbore S, Popp J, Frosch T. Online investigation of respiratory quotients in Pinus sylvestris and Picea abies during drought and shading by means of cavity-enhanced Raman multi-gas spectrometry. Analyst 2015; 140:4473-81. [DOI: 10.1039/c5an00402k] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
CERS monitoring of RQ values enables the analysis of nutrition shifts in trees in response to environmental stress.
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Affiliation(s)
- Stefan Hanf
- Leibniz Institute of Photonic Technology
- Jena
- Germany
- Max Planck Institute for Biogeochemistry
- Jena
| | | | | | | | | | - Jürgen Popp
- Leibniz Institute of Photonic Technology
- Jena
- Germany
- Friedrich Schiller University
- Institute for Physical Chemistry
| | - Torsten Frosch
- Leibniz Institute of Photonic Technology
- Jena
- Germany
- Friedrich Schiller University
- Institute for Physical Chemistry
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