Journal articles: 'Spectroscopie de fluorescence'

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ANDUEZA, D., B. P. MOUROT, A. AÏT-KADDOUR, S. PRACHE, and J. MOUROT. "Utilisation de la spectroscopie dans le proche infrarouge et de la spectroscopie de fluorescence pour estimer la la qualité et la traçabilité de la viande." INRA Productions Animales 28, no. 2 (January 13, 2020): 197–208. http://dx.doi.org/10.20870/productions-animales.2015.28.2.3025.

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Ces dernières années, la spectroscopie dans le proche infrarouge et la spectroscopie de fluorescence ont fait preuve d’une efficacité remarquable pour l’obtention d’estimations rapides et précises des paramètres de qualité des produits agricoles. Cette synthèse fait le point de l’état des connaissances sur l’application de ces technologies pour l’estimation de la qualité de la viande et des produits carnés. Un bref rappel des fondements théoriques des techniques est d’abord exposé. Les possibilités actuelles de leur application analytique aux différents paramètres de la qualité de la viande sont ensuite décrites. Les deux techniques montrent un grand potentiel pour la prédiction des composants du muscle et la détermination des différents paramètres de la qualité de la viande. Cependant, malgré l’important effort de recherche réalisé jusqu’à présent sur le sujet, la plupart des résultats montrent que leur utilisation pratique reste encore limitée. Les causes de ces performances sont décrites. Les résultats de l’utilisation de la spectroscopie dans le proche infrarouge dans une optique de traçabilité sont plus prometteurs. Cette technologie peut être utilisée pour détecter différentes types de viande entrant dans la composition des produits carnés, différencier la viande fraiche de la viande décongelée ou pour authentifier l’alimentation des animaux.

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McGuire, Hugo, and Rikard Blunck. "La spectroscopie de fluorescence pour détecter les changements de conformation en canaux unitaires." médecine/sciences 25, no. 11 (November 2009): 951–54. http://dx.doi.org/10.1051/medsci/20092511951.

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Ellingsen, G., and S. Fery-Forgues. "Application de la spectroscopie de fluorescence a l'étude du pétrole : le défi de la complexité." Revue de l'Institut Français du Pétrole 53, no. 2 (March 1998): 201–16. http://dx.doi.org/10.2516/ogst:1998019.

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Le Coupannec, F., and J. J. Peron. "Fractionnement et caractérisation des lixiviats de centres d'enfouissement technique de déchets ménagers: intérêt de la chromatographie liquide haute performance sur le gel d'exclusion stérique." Revue des sciences de l'eau 12, no. 3 (April 12, 2005): 529–43. http://dx.doi.org/10.7202/705364ar.

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L'ultrafiltration et la chromatographie d'exclusion stérique haute performance sont utilisées pour la séparation et la caractérisation des composés organiques présents dans les lixiviats de centres d'enfouissement technique de déchets ménagers. Le fractionnement de la matière organique est obtenu sur des colonnes type TSK PW, en élution eau pH 4 et eau-méthanol. La spectroscopie en UV-visible et en fluorescence, un détecteur évaporatif à diffusion de lumière sont utilisés pour la caractérisation des fractions. Cette méthode rapide de séparation associée à une multidétection permet une mise en évidence, dans les fractions issues de l'ultrafiltration, de composés organiques caractéristiques. Dans la fraction de poids moléculaires inférieurs à 1000 Daltons, trois familles sont détectées. Les substances humiques et les protéines sont les principaux groupes présents dans la fraction de poids moléculaires supérieurs à 10000 Daltons.

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Gaye-Seye, MD, G. Dodin, and JJ Aaron. "Étude par spectroscopie de fluorescence de l’effet du pH sur la complexation de la cinchonine par la β-lactoglobuline (β-LG)." Journal de Chimie Physique 94 (1997): 1208–15. http://dx.doi.org/10.1051/jcp/1997941208.

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Fanget, B., O. Devos, and E. Naffrechoux. "Rôle des acides humiques dans le transfert du pyrène entre les minéraux argileux et l'eau." Revue des sciences de l'eau 15 (April 12, 2005): 95–108. http://dx.doi.org/10.7202/705488ar.

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Les substances humiques se fixent en surface des minéraux argileux et modifient les sites d'adsorption des polluants organiques hydrophobes (POH). Parallèlement, les substances humiques dissoutes complexent les POH non ioniques selon des mécanismes de liaison réversible généralement évalués par le coefficient de partage Koc. Les solutés humiques seraient ainsi responsables du transport des POH dans les écosystèmes aquatiques par solubilisation de la fraction adsorbée sur le sédiment. Notre étude a pour objectif la quantification et la modélisation de ces phénomènes pour des composés modèles disponibles commercialement : kaolinite, pyrène et acide humique Aldrich purifié. L'isotherme d'adsorption de l'acide humique (AH) sur la kaolinite à pH 6,5 et à force ionique 10-2 M suit une loi de Freundlich, dont les valeurs du modèle sont KF =0,79 et nF =1,90. Dans les mêmes conditions expérimentales, le pyrène, composé modèle à quatre noyaux du groupe des hydrocarbures aromatiques polycycliques (HAP), semble s'adsorber en formant des microcristaux à la surface de l'argile. La présence d'acide humique fixé sur la kaolinite modifie l'adsorption du pyrène, qui se modélise par une isotherme de Freundlich de paramètres K'F =0,30 et n'F =2,00. Les interactions entre le pyrène et l'acide humique dissous ont été quantifiées par spectroscopie d'extinction de fluorescence et relation de Stern-Volmer. La fraction humique dissoute non adsorbée sur le minéral argileux se caractérise par de plus fortes valeurs de Koc que l'acide humique initial (2,95.105 L.kg-1 contre 1,86.105 L.kg-1). L'hypothèse de fractionnement des substances humiques lors de l'adsorption sur l'argile est confirmée par les variations du poids moléculaire moyen des AH, déterminé par chromatographie d'exclusion stérique, et des variations des intensités de fluorescence des fractions chromatographiées. Les résultats obtenus pour la quantification du pyrène désorbé du solide argileux dans l'eau pure et dans une solution d'AH (50 mg.L-1) tendent à minimiser le rôle de la matière organique naturelle dissoute dans le transfert des polluants hydrophobes du milieu solide au milieu liquide.

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Savickienė, Viktorija, Aurimas Bieliauskas, Sergey Belyakov, Eglė Arbačiauskienė, and Algirdas Šačkus. "Multicomponent Synthesis of New Fluorescent Boron Complexes Derived from 3-Hydroxy-1-phenyl-1H-pyrazole-4-carbaldehyde." Molecules 29, no. 14 (July 22, 2024): 3432. http://dx.doi.org/10.3390/molecules29143432.

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Novel fluorescent pyrazole-containing boron (III) complexes were synthesized employing a one-pot three-component reaction of 3-hydroxy-1-phenyl-1H-pyrazole-4-carbaldehyde, 2-aminobenzenecarboxylic acids, and boronic acids. The structures of the novel heterocyclic compounds were confirmed using 1H-, 13C-, 15N-, 19F-, and 11B-NMR, IR spectroscopy, HRMS, and single-crystal X-ray diffraction data. The photophysical properties of the obtained iminoboronates were investigated using spectroscopic techniques, such as UV–vis and fluorescence spectroscopies. Compounds display main UV–vis absorption maxima in the blue region, and fluorescence emission maxima are observed in the green region of the visible spectrum. It was revealed that compounds exhibit fluorescence quantum yield up to 4.3% in different solvents and demonstrate an aggregation-induced emission enhancement effect in mixed THF–water solutions.

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Hamon, Caroline, Solenn Reguer, Vérane Brisotto, Cécile Le Carlier de Veslud, Klet Donnart, Stéphane Blanchet, Yvan Pailler, Yoann Escats, and Ludovic Bellot-Gourlet. "Des outils de métallurgistes dans le Bronze ancien de Bretagne ? Révéler le rôle du macro-outillage lithique en associant analyses tracéologiques et de spectroscopie de fluorescence X." Bulletin de la Société préhistorique française 118, no. 4 (2021): 697–737. http://dx.doi.org/10.3406/bspf.2021.15250.

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The question of the emergence and development of copper and bronze metallurgies is a major issue in addressing the cultural and economic dynamics of the late Neolithic and early Bronze Age in Western Europe. This phenomenon is particularly relevant along the Atlantic coast, where the Armorican peninsula is central for better understanding how the control of these new productions contributed to the emergence of new elites and their chiefs, notably within the Armorican Tumulus culture (2150-1750 BC). However, evidence of Early Bronze Age mining activities and metallurgical production workshops remains scarce on the Atlantic coast, particularly in the Armorican Massif. The rare sources of copper ore are generally poor which have long suggested that the presence of metallic objects discovered in the rich burials of these periods, in particular in the tumuli of the Early Bronze Age, could only be the result of imports over more or less long distances. Recent work on the composition of some Armorican bronze objects has also highlighted a close proximity to ores from Ross Island in Ireland, suggesting that ores or ingots were imported from other regions, including across the Channel. Other works have nevertheless underlined that the exploitation of local copper veins could be envisaged in the Armorican Massif, especially as copper objects appear to concentrate in this area. Therefore, the discovery of direct or indirect evidence of copper metallurgy, particularly on settlement sites, is crucial for these periods. The presence of rare crucibles, moulds and ingots, as well as hearth structures and even furnaces, are precious clues for identifying possible episodes of metallurgical production. Stone tools constitute a second group of clues attesting metallurgical production throughout the Bronze Age, since they are now known to have been used at different stages of the operating chain, from the extraction and transformation of ores to the shaping and finishing of metal objects by hammering and abrading. This paper presents the results of a combination of use-wear and elementary X-ray fluorescence spectroscopy (XRF) analysis of a series of macrolithic tools from the Armorican Peninsula. The analyzed corpus comes from five sites in Britany dated by their pottery or by radiocarbon dating to the Early Bronze Age : it includes a settlement enclosure (Bel air, Lannion), an island settlement (Beg ar Loued, Molène) as well as less structured occupations however characteristic of the period (Kersulec, Plonéour-Lanvern ; la Colignière, Trémuson ; ZAC Kerisac, Plouisy). They illustrate the diversity of the contexts encountered dating to this period in the western part of the Armorican peninsula. For each of the sites, several tools were selected from a larger corpus of macrolithic tools, based on criteria of the raw materials, type of active surfaces and nature of the use-wear traces. The assemblage includes 19 macrolithic tools : 3 crushing-grinding tools, 2 tools with cupules, 1 pestle, 2 anvils, 3 hammerstones, 1 percussion or crushing tool, 3 heaps, 3 hammers and finally 2 sharpeners. The functional analysis method is based on the combination of the results of a low and high magnification use-wear analysis and elementary X-ray fluorescence (XRF) analyses, with two implemented measurement methods : portable X-ray fluorescence spectrometer (pXRF) and X-ray fluorescence mapping under Synchrotron radiation (Sy-XRF). The use-wear analysis alone therefore made it possible to exclude metallurgical use for 3 of the 13 tools analyzed, the other 10 tools showing traces at least linked to the working of mineral materials, with three quarters of them showing a combination of traces strongly suggesting the working of ore or metal. The combination of the use-wear and XRF analyses allows us to propose a use for ore processing or the transformation of metallic materials for 8 of these 10 tools. This result underlines that the hypotheses formulated following the use-wear analysis are well supported by the elementary residue analyses. The p-XRF analysis is able to detect copper residues even in relatively small quantities and to detect the heavier elements, such as tin. An average quantification is obtained, representing an analytical area of about 3 mm. Furthermore, the analytical precision permitted by Sy-XRF analysis, thanks in particular to the elemental distribution maps, with a selected resolution of a few tens of micrometers, makes it possible to distinguish chemical elements from the minerals making up the heterogeneous rocks generally used for macro-tools from the residues of processed materials that had catched on the surface. It also shows the correlations between the elementary distributions and the areas showing the traces of use. Due to the implementation modalities, the complementarity and concordance of the results of the Sy-XRF and p-XRF analyses with regard to the detection of copper residues is therefore stressed here. These analyses highlight the use of crushing tools, hammers and sharpeners for the working of copper alloy objects at all stages of the metal production and processing chain (production, shaping, maintenance). The identification of different types of metallurgists'' tools, some of them specialized, raises questions about the representation of this activity in a wide variety of Early Bronze Age contexts. It also underlines the question of the division of the operating chain in time and space, in particular between the extraction areas, primary metallurgy aimed at metal production and secondary metallurgy dedicated to the shaping or even finishing of the objects. The different occupation contexts from which these tools originate suggest a production of copper alloys, which despite its discretion in the archaeological record, must undoubtedly have been more important than initially envisaged. The presence of such tools in Armorican funerary contexts for the Early Bronze Age echoes these results.

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Anderson, T. Anthony, Jeon Woong Kang, Tatyana Gubin, Ramachandra R. Dasari, and Peter T. C. So. "Raman Spectroscopy Differentiates Each Tissue from the Skin to the Spinal Cord." Anesthesiology 125, no. 4 (October 1, 2016): 793–804. http://dx.doi.org/10.1097/aln.0000000000001249.

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Abstract Background Neuraxial anesthesia and epidural steroid injection techniques require precise anatomical targeting to ensure successful and safe analgesia. Previous studies suggest that only some of the tissues encountered during these procedures can be identified by spectroscopic methods, and no previous study has investigated the use of Raman, diffuse reflectance, and fluorescence spectroscopies. The authors hypothesized that real-time needle-tip spectroscopy may aid epidural needle placement and tested the ability of spectroscopy to distinguish each of the tissues in the path of neuraxial needles. Methods For comparison of detection methods, the spectra of individual, dissected ex vivo paravertebral and neuraxial porcine tissues were collected using Raman spectroscopy (RS), diffuse reflectance spectroscopy, and fluorescence spectroscopy. Real-time spectral guidance was tested using a 2-mm inner-diameter fiber-optic probe-in-needle device. Raman spectra were collected during the needle’s passage through intact paravertebral and neuraxial porcine tissue and analyzed afterward. The RS tissue signatures were verified as mapping to individual tissue layers using histochemical staining and widefield microscopy. Results RS revealed a unique spectrum for all ex vivo paravertebral and neuraxial tissue layers; diffuse reflectance spectroscopy and fluorescence spectroscopy were not distinct for all tissues. Moreover, when accounting for the expected order of tissues, real-time Raman spectra recorded during needle insertion also permitted identification of each paravertebral and neuraxial porcine tissue. Conclusions This study demonstrates that RS can distinguish the tissues encountered during epidural needle insertion. This technology may prove useful during needle placement by providing evidence of its anatomical localization.

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Delledonne, Chiara, Michela Albano, Tommaso Rovetta, Gianmarco Borghi, Mario Gentile, Anna Denia Marvelli, Piero Mezzabotta, et al. "Rediscovering the Painting Technique of the 15th Century Panel Painting Depicting the Coronation of the Virgin by Michele di Matteo." Heritage 7, no. 1 (January 10, 2024): 324–37. http://dx.doi.org/10.3390/heritage7010016.

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The study concerned a diagnostic spectroscopic campaign carried out on the panel painting depicting the Coronation of the Virgin (first half of the 15th century) by the late-Gothic Italian painter Michele di Matteo. The main aims were the identification of the original painting materials and the characterization of the painter’s artistic technique. A combined approach based on non- and micro-invasive techniques was employed. Visible and ultraviolet-induced fluorescence photography was used to select the areas of interest for spectroscopic analyses; X-ray radiography assessed the state of conservation of the support, while X-ray fluorescence and external reflection Fourier transform infrared spectroscopies allowed the chemical identification of pigments, binders, and varnishes. Attenuated total reflection infrared spectroscopy, optical microscopy, and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy were used to visualize and characterize the materials in the pictorial layers. The results highlighted the presence of pigments, possibly applied with an egg binder, consistent with the period of the production of the painting, as well as modern pigments used during subsequent restorations: an imprimitura with lead white and a gypsum-based ground layer. Concerning the gilding, the guazzo technique was confirmed by identifying a red bolo substrate and gold leaf.

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A Mas, P., D. J-R Bouveresse, and I. Birlouez-Aragon. "Fluorescence spectroscopy for monitoring rapeseed oil upon heating." Czech Journal of Food Sciences 22, SI - Chem. Reactions in Foods V (January 1, 2004): S127—S129. http://dx.doi.org/10.17221/10634-cjfs.

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The aim of this work was to determine the heating effect on the thermo-degradation process of rapeseed oil (RO) by rapid fluorescence method. Reference measurements were carried out by chromatographic methods in order to compare results with those obtained by fluorescence spectroscopy. The main compounds which were monitored are polar compounds and tocopherols. During heating process, two temperatures were used: 171°C and 189°C for 4.5 h. The results have showed that the tocopherol content decreases, especially at the highest temperature, and the polar content increases of 20% at the end of heating. These results are in agreement with literature. PLS model was built in order to predict polar and tocopherol contents. The results obtained from this method were satisfactory.

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Assaad, Aziz, Marc Benoit, Eliane Cablé, Michelle Cussenot, and Marie-Noëlle Pons. "Expérience de recherche participative dans le bassin du Madon (Lorraine, France)." Revue des sciences de l’eau 28, no. 3 (November 10, 2015): 199–205. http://dx.doi.org/10.7202/1034008ar.

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Résumé La recherche participative (ou recherche citoyenne) permet d’établir un partenariat entre le milieu académique (laboratoire universitaire et ses chercheurs) et le milieu associatif ou scolaire pour réaliser des études à visée scientifique. Elles permettent à la fois de mieux faire apprécier la démarche scientifique au grand public (qu’il s’agisse d’enfants ou d’adultes) et d’obtenir des données, sur le long terme ou sur un grand secteur géographique, utiles au chercheur. C’est dans ce cadre que deux actions se sont déroulées entre 2012 et 2014 sur le bassin du Madon, l’un des affluents de la Moselle, dans le sud de la Lorraine. Une première action a été réalisée dans le cadre d’une manifestation socioculturelle (les Chemins de l’Eau) organisée par la Fédération Départementale des Foyers Ruraux en juin 2013 : afin de sensibiliser les visiteurs aux ressources en eau dans leur environnement immédiat, une hydrothèque a été créée. La seconde action s’est adressée à des classes de primaire (CE2-CM1-CM2 et CM2) de trois localités rurales le long du Madon (Lerrain, Mattaincourt et Haroué). Tous les échantillons ont ensuite fait l’objet d’analyses au laboratoire : pH, conductivité, carbone organique dissous, azote total dissous, azote ammoniacal, ions majeurs, propriétés optiques (spectroscopie UV-visible, fluorescence). Ces expériences ont permis d’avoir un suivi temporel de trois stations le long du Madon et de participer à une cartographie des ressources en eau des Vosges en fonction des caractéristiques du bassin versant et de l’usage des sols. Dans les deux cas, le public visé a montré un vif intérêt.

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Xue, Mao-Yun, Ai-Ping Yang, Mei-Hua Ma, and Xiao-Hua Li. "The application of two-dimensional fluorescence correlation spectroscopy on the interaction between bovine serum albumin and prulifloxacin." Spectroscopy 23, no. 5-6 (2009): 257–63. http://dx.doi.org/10.1155/2009/565173.

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The interaction between bovine serum albumin (BSA) and prulifloxacin was investigated by ultraviolet spectrophotometer (UV) and fluorescence spectroscopy in this paper. Two-dimensional (2D) correlation spectroscopy was applied to the analysis of fluorescence spectra. The results of spectroscopic measurements suggested that prulifloxacin (PL) have a strong ability to quench the intrinsic fluorescence of bovine serum albumin through static quenching procedure. Thermodynamic parameter enthalpy changes (ΔH) and entropy changes (ΔS) were calculated. Owing to the spectral resolution enhancement in 2D correlation spectroscopy, the structure change of prulifloxacin can be observed.

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Ridgeway, William K., David P. Millar, and James R. Williamson. "The Spectroscopic Basis of Fluorescence Triple Correlation Spectroscopy." Journal of Physical Chemistry B 116, no. 6 (February 8, 2012): 1908–19. http://dx.doi.org/10.1021/jp208605z.

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KOBAYASHI, NAGAO. "Theoretical interpretation of spectroscopic data." Journal of Porphyrins and Phthalocyanines 04, no. 04 (June 2000): 377–79. http://dx.doi.org/10.1002/(sici)1099-1409(200006/07)4:4<377::aid-jpp236>3.0.co;2-3.

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This paper provides a short, representative summary of recent progress in the electronic absorption, magnetic and natural circular dichroism, fluorescence and phosphorescence emission, and IR and Raman vibrational spectroscopies of porphyrine and phthalocyanine compounds. These spectroscopies are discussed in the microsymposium entitled ‘Theoretical Interpretation of Spectroscopic Data’.

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Goldrick, Stephen, David Lovett, Gary Montague, and Barry Lennox. "Influence of Incident Wavelength and Detector Material Selection on Fluorescence in the Application of Raman Spectroscopy to a Fungal Fermentation Process." Bioengineering 5, no. 4 (September 25, 2018): 79. http://dx.doi.org/10.3390/bioengineering5040079.

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Raman spectroscopy is a novel tool used in the on-line monitoring and control of bioprocesses, offering both quantitative and qualitative determination of key process variables through spectroscopic analysis. However, the wide-spread application of Raman spectroscopy analysers to industrial fermentation processes has been hindered by problems related to the high background fluorescence signal associated with the analysis of biological samples. To address this issue, we investigated the influence of fluorescence on the spectra collected from two Raman spectroscopic devices with different wavelengths and detectors in the analysis of the critical process parameters (CPPs) and critical quality attributes (CQAs) of a fungal fermentation process. The spectra collected using a Raman analyser with the shorter wavelength (903 nm) and a charged coupled device detector (CCD) was corrupted by high fluorescence and was therefore unusable in the prediction of these CPPs and CQAs. In contrast, the spectra collected using a Raman analyser with the longer wavelength (993 nm) and an indium gallium arsenide (InGaAs) detector was only moderately affected by fluorescence and enabled the generation of accurate estimates of the fermentation’s critical variables. This novel work is the first direct comparison of two different Raman spectroscopy probes on the same process highlighting the significant detrimental effect caused by high fluorescence on spectra recorded throughout fermentation runs. Furthermore, this paper demonstrates the importance of correctly selecting both the incident wavelength and detector material type of the Raman spectroscopy devices to ensure corrupting fluorescence is minimised during bioprocess monitoring applications.

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Heldt, Józef, Janina R. Heldt, and Jerzy Kamiński. "Steady-state and Time-resolved Spectroscopic Studies of Benzanilides." Zeitschrift für Naturforschung A 54, no. 8-9 (September 1, 1999): 495–502. http://dx.doi.org/10.1515/zna-1999-8-909.

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Steady-state and time-resolved spectroscopic studies of benzanilide (I) and jV-methylbenzanilide (II)were performed at 298 and 77 K in various solvents. The results indicate that benzanilide fluorescencein non-polar solvents at room temperature involves three independent modes of emission: F1 (LE) normalfluorescence from the initially excited state S1 (LE) with λmax = 320 nm, F2´(PT) fluorescence from the proton transfer tautomer with λmax = 468 nm, F2″CT) fluorescence from the species where intramolecular charge transfer appears, with λmax = 510 nm. At 77 K in MCH a new fluorescence band, Fag, appears at λmax=415 nm instead of the F2(PT) and F2″CT) fluorescence. This new emission originates from benzanilide dipolar aggregates or cis-imidol dimers. The decay times of these emission modes aredifferent.N-methylbenzanilide, dissolved in nonpopular and weakly polar solvents at room temperature and at77 K, shows only two fluorescence modes, i.e., the normal and the charge-transfer emissions at 320 nmand 520 nm, respectively. The fluorescence is deactivated with two decay times, 30 ps and 2.05 ns, inMCH solution.

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Xu, Yue, Xiangyang Zhou, and Wenjuan Lei. "Identifying the Producer and Grade of Matcha Tea through Three-Dimensional Fluorescence Spectroscopy Analysis and Distance Discrimination." Foods 12, no. 19 (September 28, 2023): 3614. http://dx.doi.org/10.3390/foods12193614.

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The three-dimensional fluorescence spectroscopy features the advantage of obtaining emission spectra at different excitation wavelengths and providing more detailed information. This study established a simple method to discriminate both the producer and grade of matcha tea by coupling three-dimensional fluorescence spectroscopy analysis and distance discrimination. The matcha tea was extracted three times and three-dimensional fluorescence spectroscopies of these tea infusions were scanned; then, the dimension of three-dimensional fluorescence spectroscopies was reduced by the integration at three specific areas showing local peaks of fluorescence intensity, and a series of vectors were constructed based on a combination of integrated vectors of the three tea infusions; finally, four distances were used to discriminate the producer and grade of matcha tea, and two discriminative patterns were compared. The results indicated that proper vector construction, appropriate discriminative distance, and correct steps are three key factors to ensure the high accuracy of the discrimination. The vector based on the three-dimensional fluorescence spectroscopy of all three tea infusions resulted in a higher accuracy than those only based on spectroscopy of one or two tea infusions, and the first tea infusion was more sensitive than the other tea infusion. The Mahalanobis distance had a higher accuracy that was up to 100% when the vector is appropriate, while the other three distances were about 60–90%. The two-step discriminative pattern, identifying the producer first and the grade second, showed a higher accuracy and a smaller uncertainty than the one-step pattern of identifying both directly. These key conclusions above help discriminate the producer and grade of matcha in a quick, accurate, and green method through three-dimensional fluorescence spectroscopy, as well as in quality inspections and identifying the critical parameters of the producing process.

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Luo Yamei, 骆亚梅, 蹇林 Jian Lin, 罗浩奇 Luo Haoqi, 黄科赢 Huang Keying, 张沃伦 Zhang Wolun, 王柱楼 Wang Zhulou, 张会芝 Zhang Huizhi, 肖茜 Xiao Qian, and 黄韶辉 Huang Shaohui. "荧光自相关光谱技术检测抗原抗体亲和力." Acta Optica Sinica 41, no. 17 (2021): 1730004. http://dx.doi.org/10.3788/aos202141.1730004.

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Wang, Jun, Huijie Li, Yong Chen, Yuan Fang, Zongping Wang, Tao Tao, and Yuegang Zuo. "Comparative characterisation of two fulvic acids from East Lake and Liangzi Lake in central China." Environmental Chemistry 12, no. 2 (2015): 189. http://dx.doi.org/10.1071/en14135.

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Environmental context Fulvic acids account for a large proportion of dissolved organic matter in aquatic environments and affect the transportation and bioavailability of organic and inorganic pollutants. The structural and spectroscopic characteristics of fulvic acids mainly depend on the sources, seasons and anthropogenic activity. We present an advanced approach using fluorescence spectroscopy as a rapid and cost-effective method to investigate the composition, properties and origins of fulvic acids. Abstract Fulvic acids (FAs) isolated seasonally from the sediments of East Lake and Liangzi Lake in central China were comparatively investigated. The structural features of the FAs were characterised using chemical and spectroscopic methods, including elemental analysis, UV-Vis spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, and three-dimensional excitation emission matrix (EEM) fluorescence spectroscopy coupled with parallel factor analysis (PARAFAC). The O/C, (O+N)/C and C/N ratios of FA extracted from Liangzi Lake (FAL) were higher than those of FA extracted from East Lake (FAE), indicating higher oxygen-containing functionality and polarity and less nutrient in FAL compared with FAE. The two FAs had similar UV-Vis spectra with different absorbance intensities. The FT-IR spectra showed that the two FAs had similar functional groups. The total fluorescence intensity and aromaticity of samples from Liangzi Lake were higher than those of East Lake except for those taken in the summer. The two FAs were largely terrestrially derived organic materials. Five fluorescent components, including four humic-like and two fulvic-like components, were identified by PARAFAC modelling of the EEM spectral data. The fluorescence was dominated by two components. The findings suggest that EEM fluorescence spectroscopy together with PARAFAC is a rapid and cost-effective method for understanding the characteristics and origins of FAs in natural water systems.

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Hassoun, Abdo. "Exploring the Potential of Fluorescence Spectroscopy for the Discrimination between Fresh and Frozen-Thawed Muscle Foods." Photochem 1, no. 2 (September 2, 2021): 247–63. http://dx.doi.org/10.3390/photochem1020015.

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Substitution of frozen-thawed food products for fresh ones is a significant authenticity issue being extensively investigated over the past few years by various conventional methods, but little success has been achieved. Fluorescence spectroscopy is a sensitive and selective spectroscopic technique that has been widely applied recently to deal with various food quality and authenticity issues. The technique is based on the excitation of certain photosensitive components (known as fluorophores) to fluoresce in the UV and visible spectral ranges. Fluorescence spectroscopy can be performed to obtain simple classical two-dimensional fluorescence spectra (excitation/emission), synchronous or three-dimensional excitation–emission matrices (excitation/emission/fluorescence signal). The technique can be used in front-face or right-angle configurations and can be even combined with hyperspectral imaging, requiring the use of multivariate data analysis to extract useful information. In this review, we summarize the recent progress in applications of fluorescence spectroscopy to differentiate truly fresh foods from frozen-thawed products. The basics of the technique will be briefly presented and some relevant examples, focusing especially on fish and meat products, will be given. It is believed that interdisciplinary collaboration between researchers working with data analysis and spectroscopy, as well as industry and regulatory authorities would help to overcome the current shortcomings, holding the great promise of fluorescence spectroscopy for fighting food fraud in the food industry.

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Hermanto, Nur Aziani, Yusnita Juahir, Suzaliza Mustafar, Aisyah Mohamad Sharif, Uwaisulqarni M. Osman, and Alizar Ulianas. "Green Fluorescence Property of Chromone-based Hydrazone Towards Zn2+ Ion." Journal of Science and Mathematics Letters 12, no. 2 (July 11, 2024): 161–69. http://dx.doi.org/10.37134/jsml.vol12.2.13.2024.

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Excessive concentration of Zn in the environment may lead to bad toxicological responses that can affect human health and create numerous challenges in the environment. Therefore, it is very important to develop a sensitive method such as selective chemosensors based on fluorescence property which does not require laborious work in order to detect Zn metal ion. A formylchromone-thiosemicarbazide with two chloro derivatives namely DFCTSC was synthesized from reflux reaction of 6,8-dichloroformylchromone (DCF) and thiosemicarbazide (TSC) in ethanol. The characterisation of ligand structure was determined by using spectroscopic techniques such as Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-VIS) and nuclear magnetic resonance spectroscopy (NMR). Meanwhile, the fluorescence property of DFCTSC in the presence of Zn ion was recorded using fluorescence spectrophotometer. The result showed DFCTSC has a good fluorescence behaviour towards Zn ion by giving turn-on green fluorescence at peak 500 nm and emit light when it observed under UV light. The behaviour displayed the ability of ligand to be used as a potential fluorescent chemosensor for detecting Zn2+.

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Wang, Anna, Mengyang Xie, and Ligen Wu. "Spectroscopic and Molecular Docking Studies on the Influence of Inulin on the Interaction of Sophoricoside with Whey Protein Concentrate." Foods 13, no. 22 (November 11, 2024): 3601. http://dx.doi.org/10.3390/foods13223601.

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The influence of inulin on the interaction of sophoricoside (Sop) with whey protein concentrate (WPC) was investigated using various spectroscopic methods, including fluorescence spectroscopy (intrinsic fluorescence, synchronous fluorescence, and three-dimensional fluorescence), ultraviolet-visible (UV–Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and molecular docking. Sop was found to quench the intrinsic fluorescence of WPC by a static mechanism, both with and without the addition of inulin, and to enhance the antioxidant capacity of the protein. The addition of inulin slightly increased the binding distance between WPC and Sop, while reducing the number of binding sites from two to one. Non-covalent interactions, predominantly van der Waals forces and hydrogen bonding, were maintained between Sop and the protein. Synchronous fluorescence spectroscopy revealed that Sop prevents the exposure of hydrophobic groups on tryptophan residues, leading to increased surface hydrophilicity of the WPC complex. This aligns with the decreased protein surface hydrophobicity measured by 8-Anilino-1-naphthalenesulfonic acid (ANS) binding assays. With inulin, the overall hydrophobicity of the protein was lower than in the system without inulin, suggesting that both inulin and Sop improve the solubility of WPC. Three-dimensional fluorescence spectral analysis showed a reduction in fluorescence intensity and a red shift in the presence of both Sop and inulin. FTIR spectroscopy indicated a slight increase in the secondary structure ordering of WPC following the addition of both Sop and inulin, suggesting structural stabilization under heating conditions. Molecular docking highlighted the potential for hydrogen bond formation between Sop and WPC.

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Bigio, Irving J., and Judith R. Mourant. "Ultraviolet and visible spectroscopies for tissue diagnostics: fluorescence spectroscopy and elastic-scattering spectroscopy." Physics in Medicine and Biology 42, no. 5 (May 1, 1997): 803–14. http://dx.doi.org/10.1088/0031-9155/42/5/005.

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Berg, B. L., J. Ronholm, D. M. Applin, P. Mann, M. Izawa, E. A. Cloutis, and L. G. Whyte. "Spectral features of biogenic calcium carbonates and implications for astrobiology." International Journal of Astrobiology 13, no. 4 (September 10, 2014): 353–65. http://dx.doi.org/10.1017/s1473550414000366.

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AbstractThe ability to discriminate biogenic from abiogenic calcium carbonate (CaCO3) would be useful in the search for extant or extinct life, since CaCO3can be produced by both biotic and abiotic processes on Earth. Bioprecipitated CaCO3material was produced during the growth of heterotrophic microbial isolates on medium enriched with calcium acetate or calcium citrate. These biologically produced CaCO3, along with natural and synthetic non-biologically produced CaCO3samples, were analysed by reflectance spectroscopy (0.35–2.5 μm), Raman spectroscopy (532 and 785 nm), and laser-induced fluorescence spectroscopy (365 and 405 nm excitation). Optimal instruments for the discrimination of biogenic from abiogenic CaCO3were determined to be reflectance spectroscopy, and laser-induced fluorescence spectroscopy. Multiple absorption features in the visible light region occurred in reflectance spectra for most biogenic CaCO3samples, which are likely due to organic pigments. Multiple fluorescence peaks occurred in emission spectra (405 nm excitation) of biogenic CaCO3samples, which also are best attributed to the presence of organic compounds; however, further analyses must be performed in order to better determine the cause of these features to establish criteria for confirming the origin of a given CaCO3sample. Raman spectroscopy was not useful for discrimination since any potential Raman peaks in spectra of biogenic carbonates collected by both the 532 and 785 nm lasers were overwhelmed by fluorescence. However, this also suggests that biogenic carbonates may be identified by the presence of this organic-associated fluorescence. No reliable spectroscopic differences in terms of parameters such as positions or widths of carbonate-associated absorption bands were found between the biogenic and abiogenic carbonate samples. These results indicate that the presence or absence of organic matter intimately associated with carbonate minerals is the only potentially useful spectral discriminator for the techniques that were examined, and that multiple spectroscopic techniques are capable of detecting the presence of associated organic materials. However, the presence or absence of intimately associated organic matter is not, in itself, an indicator of biogenicity.

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Liu, Mihaela, Zhigao Wang, and Xinyou Liu. "Spectroscopic Techniques for Identifying Pigments in Polychrome Cultural Relics." Coatings 15, no. 1 (December 28, 2024): 20. https://doi.org/10.3390/coatings15010020.

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This article explores recent advancements in non-destructive spectroscopic techniques for identifying pigments in polychrome cultural relics, emphasizing their significance for sustainability in cultural heritage preservation. Techniques such as infrared spectroscopy, Raman spectroscopy, and X-ray fluorescence spectroscopy facilitate the accurate identification of pigment compositions while ensuring the integrity of the artifacts is maintained. Our findings indicate that integrating multiple spectroscopic methods enhances the accuracy of pigment identification and deepens our understanding of the structural and preservation status of historical artifacts. We also outline future directions for spectroscopic analysis in the field of cultural heritage, including micro-area analysis, data fusion, and intelligent data processing, aimed at improving the efficiency and effectiveness of pigment identification, ultimately contributing to the sustainable preservation of cultural assets.

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Ahmed, Ismail A., Arusha Acharyya, Christina M. Eng, Jeffrey M. Rodgers, William F. DeGrado, Hyunil Jo, and Feng Gai. "4-Cyanoindole-2′-deoxyribonucleoside as a Dual Fluorescence and Infrared Probe of DNA Structure and Dynamics." Molecules 24, no. 3 (February 8, 2019): 602. http://dx.doi.org/10.3390/molecules24030602.

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Unnatural nucleosides possessing unique spectroscopic properties that mimic natural nucleobases in both size and chemical structure are ideally suited for spectroscopic measurements of DNA/RNA structure and dynamics in a site-specific manner. However, such unnatural nucleosides are scarce, which prompts us to explore the utility of a recently found unnatural nucleoside, 4-cyanoindole-2′-deoxyribonucleoside (4CNI-NS), as a site-specific spectroscopic probe of DNA. A recent study revealed that 4CNI-NS is a universal nucleobase that maintains the high fluorescence quantum yield of 4-cyanoindole and that among the four natural nucleobases, only guanine can significantly quench its fluorescence. Herein, we further show that the C≡N stretching frequency of 4CNI-NS is sensitive to the local environment, making it a useful site-specific infrared probe of oligonucleotides. In addition, we demonstrate that the fluorescence-quencher pair formed by 4CNI-NS and guanine can be used to quantitatively assess the binding affinity of a single-stranded DNA to the protein system of interest via fluorescence spectroscopy, among other applications. We believe that this fluorescence binding assay is especially useful as its potentiality allows high-throughput screening of DNA–protein interactions.

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Sádecká, J., and J. Tóthová. "Fluorescence spectroscopy and chemometrics in the food classification − a review." Czech Journal of Food Sciences 25, No. 4 (January 7, 2008): 159–74. http://dx.doi.org/10.17221/687-cjfs.

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This review deals with the last few years’ articles on various fluorescence techniques (conventional, excitation-emission matrix, and synchronous fluorescence spectroscopy) as a tool for the classification of food samples. Chemometric methods as principal component analysis, hierarchical cluster analysis, parallel factor analysis, and factorial discriminate analysis are briefly reminded. The respective publications are then listed according to the food samples: dairy products, eggs, meat, fish, edible oils, and others.

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Cheikhousman, R., M. Zude, D. J-R Bouveresse, D. N Rutledge, and I. Birlouez-Aragon. "Fluorescence spectroscopy for monitoring extra virgin olive oil deterioration upon heating." Czech Journal of Food Sciences 22, SI - Chem. Reactions in Foods V (January 1, 2004): S147—S150. http://dx.doi.org/10.17221/10640-cjfs.

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Fluorescence spectroscopy is a reliable and fast method for determining the deterioration of extra virgin olive oil (EVOO). EVOO was analysed by HPLC for determining antioxidant changes in EVOO due to heating at 170°C for 3 h. This thermal oxidation caused a significant exponential decrease in hydroxytyrosol (OH-Tyr) and vitamin E (vitE), while the reduction in the tyrosol content was relatively small. Hydroperoxydes were analysed by an indirect colorimetric method. Their content decreased exponentially during the heating process. Fluorescence excitation spectra with emission wavelength at 330 nm were recorded to monitor the evolution of polyphenols and vitE, while fluorescence excitation spectra with emission at 450 nm were used to monitor the evolution of hydroperoxydes. Results of partial least-square calibration models (PLS) show that the degradation of polyphenols, vitE and hydroperoxide, as well as formation of fluorescent components derivatives can be quantified with fluorescence spectroscopy. Application of chemometrical data analysis allows to optimise the extraction of the information contained in the data. Fluorescence can therefore be used as a rapid technique for evaluating the quality of heat-treated EVOO.

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Singh, Rajshree, Shikha Singh, Sudipta Senapati, Kheyanath Mitra, Jaydeep Singh, Susanta K. S. Gupta, Nira Misra, Pralay Maiti, and Biswajit Ray. "Study of the Fluorescence based Applications of Water Soluble (N, P) Doped Carbon Dots Synthesized via Microwave Assisted Green Pyrolysis." Nanoscience & Nanotechnology-Asia 10, no. 6 (November 30, 2020): 827–39. http://dx.doi.org/10.2174/2210681209666190807151604.

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Background: Water soluble nitrogen and phosphorus doped carbon dots (CD) have been synthesized using citric acid, tris(2-aminoethyl)amine and orthophosphoric acid via one step microwave assisted pyrolytic method. Methods: The CD synthesized has been characterized using FTIR, UV-Vis, fluorescence spectroscopy and EDAX coupled with SEM techniques. Results: SEM study has shown the formation of nanosized CD with an average size of ~18 nm. Elemental analysis via EDAX has confirmed successful incorporation of nitrogen (30.8% wt) and phosphorus (5.7% wt) atoms in it. The steady state and 3D fluorescence spectroscopic studies have shown its efficient fluorescence emission with emission maxima in the region of ~450 nm. It has shown efficient “turn off” fluorescence behaviour towards transition metal ions like Fe2+ and Co2+ ions and toxic nitrophenolic compounds like p-nitrophenol and picric acid. Its efficient interaction with BSA has been revealed in terms of fluorescence quenching of BSA by steady state, synchronous and 3D fluorescence spectroscopy. It has shown very good in vitro biocompatibility and enhanced cell adhesion properties towards NIH 3T3 fibroblast cells. Moreover, fluorescence microscopy has shown significant uptake of CD by the tested cell line. Conclusion: Such bio-compatible nitrogen and phosphorous doped CD can be potentially useful to estimate metal ions, p-nitrophenol and picric acid using fluorescence spectroscopy and for fluorescence based bio-imaging.

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Kashani Zadeh, Hossein, Mike Hardy, Mitchell Sueker, Yicong Li, Angelis Tzouchas, Nicholas MacKinnon, Gregory Bearman, et al. "Rapid Assessment of Fish Freshness for Multiple Supply-Chain Nodes Using Multi-Mode Spectroscopy and Fusion-Based Artificial Intelligence." Sensors 23, no. 11 (May 28, 2023): 5149. http://dx.doi.org/10.3390/s23115149.

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This study is directed towards developing a fast, non-destructive, and easy-to-use handheld multimode spectroscopic system for fish quality assessment. We apply data fusion of visible near infra-red (VIS-NIR) and short wave infra-red (SWIR) reflectance and fluorescence (FL) spectroscopy data features to classify fish from fresh to spoiled condition. Farmed Atlantic and wild coho and chinook salmon and sablefish fillets were measured. Three hundred measurement points on each of four fillets were taken every two days over 14 days for a total of 8400 measurements for each spectral mode. Multiple machine learning techniques including principal component analysis, self-organized maps, linear and quadratic discriminant analyses, k-nearest neighbors, random forest, support vector machine, and linear regression, as well as ensemble and majority voting methods, were used to explore spectroscopy data measured on fillets and to train classification models to predict freshness. Our results show that multi-mode spectroscopy achieves 95% accuracy, improving the accuracies of the FL, VIS-NIR and SWIR single-mode spectroscopies by 26, 10 and 9%, respectively. We conclude that multi-mode spectroscopy and data fusion analysis has the potential to accurately assess freshness and predict shelf life for fish fillets and recommend this study be expanded to a larger number of species in the future.

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يسر رائد محمد and وليد صلاح عبد الوهاب. "Studying The Fluorescence Resonance Energy Transfer between Fluorescein and Rhodamine B in an aqueous solution." journal of the college of basic education 28, no. 117 (December 31, 2022): 1–12. http://dx.doi.org/10.35950/cbej.v28i117.9066.

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The energy transfer of fluorescence resonance in aqueous solution was studied between two organic dyes, Fluorescein and Rhodamine B. Both dyes were found in solution as monomers, according to spectroscopic studies. Energy transfer was observed in fluorescence resonance imaging solutions containing fluorescein and rhodamine B. with different concentrations of the acceptor RhB dye in the range of (1.5×10-5 M to 3.5×10-5M). Studies using Both UV–vis absorption and fluorescence spectroscopy demonstrated that the two dyes, when dissolved in solution, appear largely as monomers.

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Pospíšilová, Ľ., N. Fasurová, and V. Petrášová. " Humus content and quality under different soil tillage systems." Soil and Water Research 5, No. 3 (September 16, 2010): 90–95. http://dx.doi.org/10.17221/20/2009-swr.

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The main objective of our study was to compare the contents and quality of humic substances in selected soil types under different tillage regimes (deep, reduced, minimum). Non destructive spectroscopic methods such as UV-VIS and synchronous fluorescence spectroscopy were applied. After three years of experiments, no statistically significant differences in the total carbon content, labile carbon content, and humic substances carbon content were found. Humic substances quality and the absorbance in UV-VIS spectral range was the highest in Haplic Chernozem (minimum tillage). Fluorescence intensity varied in dependence on the soil types, however, the same main fluorophores in all samples were detected. Fluorescence of humic substances was the highest in Haplic Chernozem (minimum tillage). The determination of HS spectroscopic characteristics was found as a sensitive indicator for HS quality assessment.

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Helgers, Heribert, Axel Schmidt, Lara Julia Lohmann, Florian Lukas Vetter, Alex Juckers, Christoph Jensch, Mourad Mouellef, Steffen Zobel-Roos, and Jochen Strube. "Towards Autonomous Operation by Advanced Process Control—Process Analytical Technology for Continuous Biologics Antibody Manufacturing." Processes 9, no. 1 (January 18, 2021): 172. http://dx.doi.org/10.3390/pr9010172.

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Continuous manufacturing opens up new operation windows with improved product quality in contrast to documented lot deviations in batch or fed-batch operations. A more sophisticated process control strategy is needed to adjust operation parameters and keep product quality constant during long-term operations. In the present study, the applicability of a combination of spectroscopic methods was evaluated to enable Advanced Process Control (APC) in continuous manufacturing by Process Analytical Technology (PAT). In upstream processing (USP) and aqueous two-phase extraction (ATPE), Raman-, Fourier-transformed infrared (FTIR), fluorescence- and ultraviolet/visible- (UV/Vis) spectroscopy have been successfully applied for titer and purity prediction. Raman spectroscopy was the most versatile and robust method in USP, ATPE, and precipitation and is therefore recommended as primary PAT. In later process stages, the combination of UV/Vis and fluorescence spectroscopy was able to overcome difficulties in titer and purity prediction induced by overlapping side component spectra. Based on the developed spectroscopic predictions, dynamic control of unit operations was demonstrated in sophisticated simulation studies. A PAT development workflow for holistic process development was proposed.

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Chinnathambi, Shanmugavel, Subramani Karthikeyan, Devadasan Velmurugan, Nobutaka Hanagata, Prakasarao Aruna, and Singaravelu Ganesan. "Effect of Moderate UVC Irradiation on Bovine Serum Albumin and Complex with Antimetabolite 5-Fluorouracil: Fluorescence Spectroscopic and Molecular Modelling Studies." International Journal of Spectroscopy 2015 (January 31, 2015): 1–12. http://dx.doi.org/10.1155/2015/315764.

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The interaction of antimetabolite 5-fluorouracil (5FU) with bovine serum albumin (BSA) under UVC (253.7 nm) irradiation was investigated in the present study using UV-Vis spectroscopy, steady state/time resolved fluorescence spectroscopic techniques. The stability of protein was found to be very strong when BSA gets bind to 5FU and moreover it is compared with the free BSA under UVC irradiation. From the fluorescence spectroscopic study, the stability of the complex was found to acquire 2-fold stronger than free protein. From the molecular modelling studies, we came to know the hydrogen bonds between BSA and antimetabolite 5FU are strong, up to 70.4 J/m2 under UVC irradiation.

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Rhind, T., J. Ronholm, B. Berg, P. Mann, D. Applin, J. Stromberg, R. Sharma, L. G. Whyte, and E. A. Cloutis. "Gypsum-hosted endolithic communities of the Lake St. Martin impact structure, Manitoba, Canada: spectroscopic detectability and implications for Mars." International Journal of Astrobiology 13, no. 4 (September 18, 2014): 366–77. http://dx.doi.org/10.1017/s1473550414000378.

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AbstractThere is increasing evidence that Mars may have once been a habitable environment. Gypsum is targeted in the search for Martian biosignatures because it can host extensive cryptoendolithic communities in extreme terrestrial environments and is widespread on Mars. In this study the viability of using different spectroscopy-based techniques to identify the presence of gypsum endolithic communities was investigated by analysing various cryptoendoliths collected from the Lake St. Martin impact crater (LSM), a Mars analogue site found in Manitoba, Canada. Concurrently, the cryptoendolithic microbial community structure present was also analysed to aid in assigning spectroscopic features to microbial community members. Two main morphologies of endolithic communities were collected from gypsum deposits at LSM: true cryptoendolithic communities and annular deposits on partially buried boulders and cobbles <1 cm below the soil surface. Endolithic communities were found to be visibly present only in gypsum with a high degree of translucency and could occur as deep as 3 cm below the exterior surface. The bacterial community was dominated by a phylum (Chloroflexi) that has not been previously observed in gypsum endoliths. The exterior surfaces of gypsum boulders and cobbles are devoid of spectroscopic features attributable to organic molecules and detectable by reflectance, Raman, or ultraviolet-induced fluorescence spectroscopies. However, exposed interior surfaces show unique endolithic signatures detectable by each spectroscopic technique. This indicates that cryptoendolithic communities can be detected via spectroscopy-based techniques, provided they are either partially or fully exposed and enough photon–target interactions occur to enable detection.

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Zacharioudaki, Despoina-Eleni, Ioannis Fitilis, and Melina Kotti. "Review of Fluorescence Spectroscopy in Environmental Quality Applications." Molecules 27, no. 15 (July 27, 2022): 4801. http://dx.doi.org/10.3390/molecules27154801.

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Fluorescence spectroscopy is an optical spectroscopic method that has been applied for the assessment of environmental quality extensively during the last 20 years. Most of the earlier works have used conventional light sources in spectrofluorometers to assess quality. Many recent works have used laser sources of light for the same purpose. The improvement of the energy sources and of the higher resolution spectrometers has led to a tremendous increase in applications. The motivation for the present review study is the increasing use of laser sources in environmental applications. The review is divided in two parts. The fundamental principles of fluorescence spectroscopy are described in the first part. The environmental applications are described in the second part.

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Wentrup-Byrne, E., L. Rintoul, J. L. Smith, and P. M. Fredericks. "Comparison of Vibrational Spectroscopic Techniques for the Characterization of Human Gallstones." Applied Spectroscopy 49, no. 7 (July 1995): 1028–36. http://dx.doi.org/10.1366/0003702953964813.

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A suite of human gallstones was investigated by vibrational spectroscopic techniques with a view to developing an effective characterization procedure. Using infrared microscopy, microspectroscopic mapping, infrared photoacoustic spectroscopy (PAS), and FT-Raman spectroscopy, we have examined both the chemical composition and the microstructure of the different categories of human gallstones. We show how infrared microscopy can be used to determine the chemical identity of particular microstructural features of a stone. Infrared mapping produces functional group maps of the surface of a gallstone and shows the actual distribution of the different chemical components. Good fluorescence-free FT-Raman spectra were obtained from all categories of stones except black stones, which gave a fluorescence background with no observable Raman spectrum. Of the vibrational techniques studied, PAS proved the most suited to the spectroscopic categorization of gallstones because data for the whole stone can be obtained with minimal sample preparation. The advantages and disadvantages of each technique are discussed.

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Vasilev, Aleksey A., Meglena I. Kandinska, Stanimir S. Stoyanov, Stanislava B. Yordanova, David Sucunza, Juan J. Vaquero, Obis D. Castaño, Stanislav Baluschev, and Silvia E. Angelova. "Halogen-containing thiazole orange analogues – new fluorogenic DNA stains." Beilstein Journal of Organic Chemistry 13 (December 28, 2017): 2902–14. http://dx.doi.org/10.3762/bjoc.13.283.

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Novel asymmetric monomeric monomethine cyanine dyes 5a–d, which are analogues of the commercial dsDNA fluorescence binder thiazole orange (TO), have been synthesized. The synthesis was achieved by using a simple, efficient and environmetally benign synthetic procedure to obtain these cationic dyes in good to excellent yields. Interactions of the new derivatives of TO with dsDNA have been investigated by absorption and fluorescence spectroscopy. The longest wavelength absorption bands in the UV–vis spectra of the target compounds are in the range of 509–519 nm and these are characterized by high molar absorptivities (63000–91480 L·mol−1·cm−1). All investigated dyes from the series are either not fluorescent or their fluorescence is quite low, but they become strongly fluorescent after binding to dsDNA. The influence of the substituents attached to the chromophores was investigated by combination of spectroscopic (UV–vis and fluorescence spectroscopy) and theoretical (DFT and TDDFT calculations) methods.

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Sabanci, Kadir, Muhammet Fatih Aslan, Vanya Slavova, and Stefka Genova. "The Use of Fluorescence Spectroscopic Data and Machine-Learning Algorithms to Discriminate Red Onion Cultivar and Breeding Line." Agriculture 12, no. 10 (October 9, 2022): 1652. http://dx.doi.org/10.3390/agriculture12101652.

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The objective of this study was to evaluate differences between the red onion cultivar and breeding line using models based on selected fluorescence spectroscopic data built using machine-learning algorithms from different groups of Trees, Functions, Bayes, Meta, Rules, and Lazy. The combination of fluorescence spectroscopy and machine learning is an original approach to the non-destructive and objective discrimination of red onion samples. The selected fluorescence spectroscopic data were used to build models using algorithms from the groups of Trees, Functions, Bayes, Meta, Rules, and Lazy. The most satisfactory results were obtained using J48 and LMT (Logistic Model Tree) from the group of Trees, Multilayer Perceptron, and QDA (Quadratic Discriminant Analysis) from Functions, Naive Bayes from Bayes, Logit Boost from Meta, JRip from Rules, and LWL (Locally Weighted Learning) from Lazy. The average accuracy of discrimination of onion bulbs belonging to ‘Asenovgradska kaba’ and a red breeding line equal to 100% was found in the case of models developed using the LMT, Multilayer Perceptron, Naive Bayes, Logit Boost, and LWL algorithms. The TPR (True Positive Rate), Precision, and F-Measure of 1.000 and FPR (False Positive Rate) of 0.000, as well as the Kappa statistic of 1.0, were determined. The results revealed the usefulness of the approach combining fluorescence spectroscopy and machine learning to distinguish red onion cultivars and breeding lines.

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Abdollahi Jahdi, Sahar, Parviz Parvin, Solaleh Seyedi, Saeid Jelvani, and Mohammad Reza Razzaghi. "Spectroscopic Characteristics of Xeloda Chemodrug." Journal of Lasers in Medical Sciences 12, no. 1 (September 25, 2021): e51-e51. http://dx.doi.org/10.34172/jlms.2021.51.

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Introduction: Spectroscopic properties of Xeloda chemodrug have been studied over varying concentrations ranging between 0.001 and 10 mg/mL, using laser-induced fluorescence (LIF) spectroscopy. The alternative photoluminescence (PL) and near infrared (NIR) measurements are carried out to authenticate the obtained results by the LIF method. Methods: The XeCl laser as the excitation coherent source with 160 mJ/pulse at 308 nm is employed for LIF measurements of the fluorophore of interest in the modular spectroscopic set-up. Results: Xeloda as a significant chemodrug acts as a notable fluorophore. LIF, PL and NIR spectroscopy techniques are employed to investigate the spectral properties of the chemodrug in terms of concentration. The maximum LIF peak intensity of Xeloda is achieved at λmax=410.5 nm and the characteristic concentration of CP1=0.05 mg/mL. PL signals are in good agreement with the data given by the LIF measurements. The characteristic NIR spectra of Xeloda as solid evidence of chemical bonding formation attest to fluorescence quenching at the fluorophore concentration of ~ 0.2 mg/ mL. Besides, the spectral shift of fluorescence signals which is obtained in terms of fluorophore concentration- demonstrating as a diagnostic marker for the purpose of optimized chemotherapy. Conclusion: Xeloda exhibits outstanding fluorescence properties over the allowable concentration in human serum (Cmax). These characteristics could benefit potential advantage of simultaneous laser-based imaging of cell-chemodrug interaction over in-vivo studies.

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Fruhner, Chris-Julian, Lkhamsuren Bayarjargal, Nadine Schrodt, Rita Luchitskaia, Wolfgang Morgenroth, and Björn Winkler. "Pressure-induced phase transition from calcite to aragonite detected by fluorescence spectroscopy." European Journal of Mineralogy 30, no. 4 (October 31, 2018): 711–20. http://dx.doi.org/10.1127/ejm/2018/0030-2759.

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Hammannavar, Preeti B., and Blaise Lobo. "Spectroscopic Studies on Films of Lead Nitrate Doped Polyvinyl Alcohol – Polyvinyl Pyrrolidone Blend." Material Science Research India 15, no. 1 (January 31, 2018): 55–67. http://dx.doi.org/10.13005/msri/150107.

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Films of polyvinyl alcohol (PVA) – polyvinyl pyrrolidone (PVP) blend doped with lead nitrate (Pb(NO3)2) were prepared by solution casting method, with doping level (DL) of Pb(NO3)2 in PVA – PVP polymeric blend varying from 2.7 up to 50.5 wt%. The prepared films were characterized using UV-Visible spectroscopy, fluorescence (or photo- luminescence) spectroscopy, FTIR and Raman spectroscopy. Parameters like optical band gaps due to indirect allowed transition (IAT) and direct allowed transition (DAT), as well as the activation energy (Ea) for optical transitions are extracted from the UV- Visible (or optical) spectra of these films. Objective of the FTIR, Raman and Fluorescence spectroscopic study is to understand the molecular chemical changes in PVA and PVP caused by the dopant (Pb(NO3)2). There is an enhancement of fluorescence intensity at DLs of 2.7 wt%, and at DL 7.6 wt%, the fluorescence intensity decreases (quenching). PVP acts as a capping agent for the dopant species, and is considered to be responsible for changes in fluorescence intensity. Signature of nitrate ion (NO3-) vibration is observed at wavenumber 1037 cm-1 in Raman spectra, and in the FTIR spectra, the NO3- vibration is seen at the wavenumber equal to 1380 cm-1.

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Bunkin, Alexey F., Sergey M. Pershin, Diana G. Artemova, Sergey V. Gudkov, Alexey V. Gomankov, Pavel A. Sdvizhenskii, Mikhail Ya Grishin, and Vasily N. Lednev. "Fossil Plant Remains Diagnostics by Laser-Induced Fluorescence and Raman Spectroscopies." Photonics 10, no. 1 (December 24, 2022): 15. http://dx.doi.org/10.3390/photonics10010015.

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Fossilized plant remains have been studied simultaneously by laser induced fluorescence and Raman spectroscopies, to reveal the prospective methods for onsite or/and laser remote sensing in future extraterrestrial missions. A multiwavelength instrument, capable of fluorescence and Raman measurements, has been utilized for the study of isolated plant fossils, as well as fossils associated with sedimentary rocks. Laser-induced fluorescence spectroscopy revealed that plant fossils and rocks’ luminosity differed significantly due to chlorophyll derivatives (chlorin, porphyrins, lignin components etc.); therefore, fossilized plants can be easily detected at rock surfaces onsite. Raman spectroscopy highly altered the fossilized graphitic material via the carbon D and G bands. Our results demonstrated that combined laser-induced fluorescence and Raman spectroscopy measurements can provide new insights into the detection of samples with biogenicity indicators such as chlorophyll and its derivatives, as well as kerogenous materials. The prospects of multiwavelength LIDAR instrument studies under fieldwork conditions are discussed for fossils diagnostics. The method of laser remote sensing can be useful in geological exploration in the search for oil, coal-bearing rocks, and rocks with a high content of organic matter.

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Kadıoğlu, Yusuf Kağan, Zafer Üstündağ, and Zafer Yazıcıgil. "Spectroscopic Application of Realgar Using X-ray Fluorescence and Raman Spectroscopy." Spectroscopy Letters 42, no. 3 (March 24, 2009): 121–28. http://dx.doi.org/10.1080/00387010902728825.

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Maklygina, Yu S., I. D. Romanishkin, A. S. Skobeltsin, T. A. Savelyeva, A. A. Potapov, G. V. Pavlova, I. V. Chekhonin, O. I. Gurina, and V. B. Loschenov. "Time-resolved fluorescence imaging technique for rat brain tumors analysis." Journal of Physics: Conference Series 2058, no. 1 (October 1, 2021): 012028. http://dx.doi.org/10.1088/1742-6596/2058/1/012028.

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Abstract The paper presents a new approach to assessing the state of tissues that differ in phenotype and in the degree of immunocompetent cells activity using photosensitizers (PS) and time-resolved fluorescence analysis methods. The main attention is paid to the detection of differences between tumor cells and tumor-associated macrophages (TAM) using spectroscopic and microscopic methods by the fluorescent kinetics signal and the difference in the accumulation of PS (the accumulation is several times greater in macrophages). The results of the PS photoluminescence study were obtained using two different techniques: time-resolved spectroscopy and time-resolved fluorescence microscopy (FLIM). Time-resolved spectroscopic analysis of the PS fluorescence lifetime was performed on adult female rats with induced C6 glioma in vivo. 5-ALA-induced Pp IX, which is widely used in clinical practice for carrying out effective conduction photodiagnostics and PDT, was used as the PS.

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Pons, M. N., O. Potier, S. Pontvianne, N. Laurent, X. France, and P. Battaglia. "Spectrophotometric characterization of human impacted surface waters in the Moselle watershed." Water Science and Technology 64, no. 3 (August 1, 2011): 602–9. http://dx.doi.org/10.2166/wst.2011.071.

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In order to characterize the pollution discharged into the Moselle River and some of its tributaries, spectroscopic techniques, namely UV–vis spectroscopy and synchronous fluorescence spectroscopy, have been combined. UV–visible spectra were analysed using the maximum of the second derivative at 225 nm (related to nitrates), the SUVA254 and E2/E3 indices (related to the nature of organic matter). Synchronous fluorescence spectra (Δλ = 50 nm) presented different shapes depending upon the type of pollution. The pollution results from anthropogenic activities: untreated domestic sewage due to misconnections in a periurban river, effluent from urban WWTPs, agricultural runoff (nitrates) in several streams, discharge from a paper mill (humic-like substances due to wood processing) and from steel mills (PAHs).

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Zhou, J. H., X. H. Wu, C. Yang, X. T. Gu, L. Zhou, K. X. Song, Y. Y. Feng, and J. Shen. "Spectroscopic studies on the interaction of hypocrellin A with myoglobin." Spectroscopy 21, no. 4 (2007): 235–43. http://dx.doi.org/10.1155/2007/503537.

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Experimental results of UV-visible absorption spectroscopy and fluorescence spectroscopy indicate that hypocrellin A, which has been studied in photodynamic therapy, can interact with the surface of myoglobin through hydrophobic forces, and form a complex. Based on the Stern–Volmer equation, the quenching constants of the process can be calculated to be 4.81×1012L mol−1s−1(t=25°C) and 4.54×1012L mol−1s−1(t=42°C) respectively, and the binding constant is 5.53×104M−1(t=25°C), while the binding sites is 0.94 (t=25°C). In addition, Electron paramagnetic resonance and fluorescence spectroscopic analysis suggests that that the quenching mechanism of the interaction process occurs through the electron transfer between hypocrellin A and myoglobin.

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Schlein, Morten, Svend Ludvigsen, Helle B. Olsen, Michael F. Dunn, and Niels C. Kaarsholm. "Spectroscopic characterization of insulin and small molecule ligand binding to the insulin receptor." Spectroscopy 16, no. 3-4 (2002): 147–59. http://dx.doi.org/10.1155/2002/136310.

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We have applied spectroscopic techniques to study two kinds of ligand binding to the insulin receptor. First, a fluorescently labelled insulin analogue is used to characterize the mechanism of reversible 1 :1 complex formation with a fragment of the insulin receptor ectodomain. The receptor induced fluorescence enhancement of the labelled insulin analogue provides the basis for stopped flow kinetic experiments. The kinetic data are consistent with a bimolecular binding event followed by a conformational change. This emphasizes the importance of insulin induced conformational changes in the activation of the insulin receptor. Second, the binding of fluorescein derivatives to the insulin receptor is studied. These small molecule ligands displace insulin from its receptor with micromolar affinity. The binding is verified by transferred NOESY NMR experiments. Their chromophoric properties are used to measure the affinity by UV-vis and fluorescence difference spectroscopies and the resulting Kdvalues are similar to those observed in the displacement receptor binding assay. However, these experiments and a stoichiometry determination indicate multiple binding sites, of which one overlaps with the insulin binding site. These two examples illustrate how spectroscopy complements biochemical receptor binding assays and provides information on ligand–insulin receptor interactions in the absence of three dimensional structures.

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Charati, Faramarz Rostami, Gholamreza Rahmani, Roya Bahadori, and Farah Sadat Madani. "A Spectroscopic and Nondestructive Analysis Methods for Investigation of Inorganic Pigments in A Cultural Heritage in North of Iran." Wood Research Journal 12, no. 1 (2021): 1–9. http://dx.doi.org/10.51850/wrj.2021.12.1.1-9.

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Many of the historical objects that form our cultural heritage are made of wood. Wooden artefacts, wood painted panels and historic furniture represent a significant part of our cultural heritage. Their preservation over time is a challenging task, and insect infestation still represents a primary cause of loss of cultural heritage artifacts. For this reason in this research, wood pigments that are important in the conservation of historical wooden objects are described. The characterization of very stable pigments from a cultural heritage building named by SAGHATALAR which is located in Mazandaran province, a suburb around of Fridonkenar city in the north of Iran near Caspian Sea (Cochakbishehmahaleh village) was investigated. The result were showed no organic materials was find in the four colors (Blue, Red, Yellow and Green) as samples of this building were detected and taken samples from them for characterization and analysis. The spectroscopic techniques that have been used are Fourier transform infrared spectroscopy (FT-IR), X‐ray fluorescence spectroscopy (XRF), X‐ray emission spectroscopy (XRD), Uv-vis spectroscopy, fluorescence spectroscopy, Raman spectroscopy and Mossbauer spectroscopy.

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Journal articles on the topic 'Spectroscopie de fluorescence'

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