Monitoring Cell Concentration and Activity by Multiple Excitation Fluorometry

Li, J.-K.; Asali, E. C.; Humphrey, Arthur E.; Horvath, J. J.

doi:10.1021/bp00007a004

Cited by 100 publications

(56 citation statements)

References 11 publications

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“…Maximum emission of fluorescence was observed at 464 nm for NAD(P)H and 525 nm for riboflavin. These results are consistent with the literature (Li et al 1991;Coghlan et al 2000;Brewer et al 2002) within the limits of the experimental error. Taking into account the excitation wavelength of the UVAPS (355 nm) and the optimal excitation wavelengths for the materials used, it becomes obvious that the UVAPS operational conditions are not optimal for producing the strongest fluorescence signals for the tested aerosols.…”

Section: Discussionsupporting

confidence: 93%

Performance Evaluation of the UVAPS in Measuring Biological Aerosols: Fluorescence Spectra from NAD(P)H Coenzymes and Riboflavin

Agranovski¹,

Ristovski²,

Ayoko³

et al. 2004

Aerosol Science and Technology

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This article presents the results of the performance evaluation of the Ultraviolet Aerodynamic Particle Sizer (UVAPS, model 3312, TSI Inc., St. Paul, MN, USA), the novel instrument for real-time monitoring of biological aerosols. The main objective of the study was to compare the UVAPS response in measuring aerosols containing NADH, NADPH, or riboflavin particles. At the excitation and emission wavelengths at which the UVAPS operates, these compounds are the primary intrinsic fluorophores specific to biological particles. In addition, the study was focused on determining the detection limits of the UVAPS for these fluorophores. This information is important for the interpretation of UVAPS data while measuring bacterial aerosols. Fluorescence measurements were initially taken with a Varian Cary Eclipse Fluorescence Spectrophotometer for all three fluorophores. The samples were then aerosolized with the 6-jet Collison nebulizer. Riboflavin was found to be a stronger fluorophore than both NAD(P)H coenzymes. The fluorescence signals were considerably weaker for the NADPH samples compared to the NADH samples. The sensitivity of the UVAPS was found to be sufficiently high to detect the NADH and riboflavin at the concentrations characteristic of bacterial cells. The results of this study are discussed in a context of the results previously reported for the bacterial aerosols. It can be concluded that the amount of fluorophores detectable in uniformly mixed particles is equal to or less than the fluorophores expected to be present in the individual bacterial particles.

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Section: Discussionsupporting

confidence: 93%

Performance Evaluation of the UVAPS in Measuring Biological Aerosols: Fluorescence Spectra from NAD(P)H Coenzymes and Riboflavin

Agranovski¹,

Ristovski²,

Ayoko³

et al. 2004

Aerosol Science and Technology

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“…Sources that provide light in the region of approximately 350Á370 nm enable detection of reduced pyridine nucleotides (e.g. NAD(P)H) and riboflavin that are biological molecules linked to cellular metabolism (Harrison and Chance, 1970;Eng et al, 1989;Kell et al, 1991;Li et al, 1991;Iwami et al, 2001). Detection of auto-fluorescence under these conditions may indicate the presence of viable biological material in the aerosol particles, although other biological molecules (e.g.…”

Section: Modern Analysis Methodsmentioning

confidence: 99%

Primary biological aerosol particles in the atmosphere: a review

Després¹,

Huffman

Burrows³

et al. 2012

Tellus B: Chemical and Physical Meteorology

1,168

1,114

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A B S T R A C T Atmospheric aerosol particles of biological origin are a very diverse group of biological materials and structures, including microorganisms, dispersal units, fragments and excretions of biological organisms. In recent years, the impact of biological aerosol particles on atmospheric processes has been studied with increasing intensity, and a wealth of new information and insights has been gained. This review outlines the current knowledge on major categories of primary biological aerosol particles (PBAP): bacteria and archaea, fungal spores and fragments, pollen, viruses, algae and cyanobacteria, biological crusts and lichens and others like plant or animal fragments and detritus. We give an overview of sampling methods and physical, chemical and biological techniques for PBAP analysis (cultivation, microscopy, DNA/RNA analysis, chemical tracers, optical and mass spectrometry, etc.). Moreover, we address and summarise the current understanding and open questions concerning the influence of PBAP on the atmosphere and climate, i.e. their optical properties and their ability to act as ice nuclei (IN) or cloud condensation nuclei (CCN). We suggest that the following research activities should be pursued in future studies of atmospheric biological aerosol particles: (1) develop efficient and reliable analytical techniques for the identification and quantification of PBAP; (2) apply advanced and standardised techniques to determine the abundance and diversity of PBAP and their seasonal variation at regional and global scales (atmospheric biogeography); (3) determine the emission rates, optical properties, IN and CCN activity of PBAP in field measurements and laboratory experiments; (4) use field and laboratory data to constrain numerical models of atmospheric transport, transformation and climate effects of PBAP.

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“…All fungal spores contain the same sources of autofluorescence such as the reducing fluorescent coenzymes nicotinamide-adenine dinucleotide (NADH) and nicotinamide-adenine dinucleotide phosphate (NADPH), as well as the metabolic function riboflavin (vitamin B 2 ) (Billinton and Knight, 2001;Brosseau et al, 2000;Li et al, 1991). However, fluorescent intensity of these biomolecules may vary according to the environmental conditions under which the fungal colonies are placed, and due to their concentration.…”

Section: The Effect Of Age On the Fungal Spore Fluorescent Intensitymentioning

confidence: 99%

“…The main biomolecules present in fungal spores are reduced fluorescent coenzymes: nicotinamide-adenine dinucleotide (NADH), nicotinamide-adenine dinucleotide phosphate (NADPH), and riboflavin (Billinton and Knight, 2001;Brosseau et al, 2000;Li et al, 1991). However, the basis of the instrument's operation, the fluorescence of the excited biomolecules, has been found to be strongly affected by environmental and biomolecule-related factors.…”

Section: Introductionmentioning

confidence: 99%

Performance assessment of UVAPS: Influence of fungal spore age and air exposure

Kanaani

Hargreaves

Ristovski

et al. 2007

Journal of Aerosol Science

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This work focused on two main outcomes. The first was the assessment of the response of the Ultraviolet Aerodynamic Particle Sizer Spectrometer (UVAPS) for two different fungal spore species.The UVAPS response was investigated as a function of fungal age and the frequency of air current that their colonies exposure to. This outcome was achieved through the measurement of fungal spore fluorescent percentage and fluorescent intensity throughout a period of culturing time (three weeks), and the study of their fluorescent percentage as a function of exposure to air currents. The second objective was to investigate the change of fungal spore size during this period, which may be of use as a co-factor in this differentiation. Fungal spores were released by blowing the surface of the culture colonies with continuous filtered flow air. The UVAPS was used to detect and measure autofluorescing biomolecules such as riboflavin and nicotinamide adenine dinucleotide phosphate (NAD(P)H) present in the released fungal spores.The study demonstrated an increase in aerodynamic diameter for fungal spores under investigation (Aspergillus niger and Penicillium species) over a period of time. The fluorescent percentage of spores was found to decrease for both fungal genera as they aged. It was also found that the fluorescent percentage for tested fungi decreased with frequency of air exposure. The results showed that, while the UVAPS could discriminate between Aspergillus and Penicillium species under well-controlled laboratory conditions, it is unlikely to be able to do so in the field.

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Monitoring Cell Concentration and Activity by Multiple Excitation Fluorometry

Cited by 100 publications

References 11 publications

Performance Evaluation of the UVAPS in Measuring Biological Aerosols: Fluorescence Spectra from NAD(P)H Coenzymes and Riboflavin

Performance Evaluation of the UVAPS in Measuring Biological Aerosols: Fluorescence Spectra from NAD(P)H Coenzymes and Riboflavin

Primary biological aerosol particles in the atmosphere: a review

Performance assessment of UVAPS: Influence of fungal spore age and air exposure

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