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15. An international laboratory comparison of dissolved organic matter composition by high resolution mass spectrometry : Are we getting the same answer?

Author

Hawkes, Jeffrey A., D'Andrilli, Juliana, Agar, Jeffrey N., Barrow, Mark P., Berg, Stephanie M., Catalan, Nuria, Chen, Hongmei, Chu, Rosalie K., Cole, Richard B., Dittmar, Thorsten, Gavard, Remy, Gleixner, Gerd, Hatcher, Patrick G., He, Chen, Hess, Nancy J., Hutchins, Ryan H. S., Ijaz, Amna, Jones, Hugh E., Kew, William, Khaksari, Maryam, Lozano, Diana Catalina Palacio, Lv, Jitao, Mazzoleni, Lynn R., Noriega-Ortega, Beatriz E., Osterholz, Helena, Radoman, Nikola, Remucal, Christina K., Schmitt, Nicholas D., Schum, Simeon K., Shi, Quan, Simon, Carsten, Singer, Gabriel, Sleighter, Rachel L., Stubbins, Aron, Thomas, Mary J., Tolic, Nikola, Zhang, Shuzhen, Zito, Phoebe, Podgorski, David C., Hawkes, Jeffrey A., D'Andrilli, Juliana, Agar, Jeffrey N., Barrow, Mark P., Berg, Stephanie M., Catalan, Nuria, Chen, Hongmei, Chu, Rosalie K., Cole, Richard B., Dittmar, Thorsten, Gavard, Remy, Gleixner, Gerd, Hatcher, Patrick G., He, Chen, Hess, Nancy J., Hutchins, Ryan H. S., Ijaz, Amna, Jones, Hugh E., Kew, William, Khaksari, Maryam, Lozano, Diana Catalina Palacio, Lv, Jitao, Mazzoleni, Lynn R., Noriega-Ortega, Beatriz E., Osterholz, Helena, Radoman, Nikola, Remucal, Christina K., Schmitt, Nicholas D., Schum, Simeon K., Shi, Quan, Simon, Carsten, Singer, Gabriel, Sleighter, Rachel L., Stubbins, Aron, Thomas, Mary J., Tolic, Nikola, Zhang, Shuzhen, Zito, Phoebe, and Podgorski, David C.

Abstract

High-resolution mass spectrometry (HRMS) has become a vital tool for dissolved organic matter (DOM) characterization. The upward trend in HRMS analysis of DOM presents challenges in data comparison and interpretation among laboratories operating instruments with differing performance and user operating conditions. It is therefore essential that the community establishes metric ranges and compositional trends for data comparison with reference samples so that data can be robustly compared among research groups. To this end, four identically prepared DOM samples were each measured by 16 laboratories, using 17 commercially purchased instruments, using positive-ion and negative-ion mode electrospray ionization (ESI) HRMS analyses. The instruments identified similar to 1000 common ions in both negative- and positive-ion modes over a wide range of m/z values and chemical space, as determined by van Krevelen diagrams. Calculated metrics of abundance-weighted average indices (H/C, O/C, aromaticity and m/z) of the commonly detected ions showed that hydrogen saturation and aromaticity were consistent for each reference sample across the instruments, while average mass and oxygenation were more affected by differences in instrument type and settings. In this paper we present 32 metric values for future benchmarking. The metric values were obtained for the four different parameters from four samples in two ionization modes and can be used in future work to evaluate the performance of HRMS instruments.

Published
2020
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26. An international laboratory comparison of dissolved organic matter composition by high resolution mass spectrometry: Are we getting the same answer?

Author

Hawkes, Jeffrey A., primary, D'Andrilli, Juliana, additional, Agar, Jeffrey N., additional, Barrow, Mark P., additional, Berg, Stephanie M., additional, Catalán, Núria, additional, Chen, Hongmei, additional, Chu, Rosalie K., additional, Cole, Richard B., additional, Dittmar, Thorsten, additional, Gavard, Rémy, additional, Gleixner, Gerd, additional, Hatcher, Patrick G., additional, He, Chen, additional, Hess, Nancy J., additional, Hutchins, Ryan H. S., additional, Ijaz, Amna, additional, Jones, Hugh E., additional, Kew, William, additional, Khaksari, Maryam, additional, Palacio Lozano, Diana Catalina, additional, Lv, Jitao, additional, Mazzoleni, Lynn R, additional, Noriega‐Ortega, Beatriz E., additional, Osterholz, Helena, additional, Radoman, Nikola, additional, Remucal, Christina K., additional, Schmitt, Nicholas D., additional, Schum, Simeon K, additional, Shi, Quan, additional, Simon, Carsten, additional, Singer, Gabriel, additional, Sleighter, Rachel L., additional, Stubbins, Aron, additional, Thomas, Mary J., additional, Tolic, Nikola, additional, Zhang, Shuzhen, additional, Zito, Phoebe, additional, and Podgorski, David C., additional

Published
2020
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29. CpeF is the bilin lyase that ligates the doubly linked phycoerythrobilin on β-phycoerythrin in the cyanobacterium Fremyella diplosiphon

Author

Kronfel, Christina M., primary, Hernandez, Carla V., additional, Frick, Jacob P., additional, Hernandez, Leanora S., additional, Gutu, Andrian, additional, Karty, Jonathan A., additional, Boutaghou, M. Nazim, additional, Kehoe, David M., additional, Cole, Richard B., additional, and Schluchter, Wendy M., additional

Published
2019
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31. Environmentally persistent free radicals amplify ultrafine particle mediated cellular oxidative stress and cytotoxicity

Author

Balakrishna Shrilatha, Lomnicki Slawo, McAvey Kevin M, Cole Richard B, Dellinger Barry, and Cormier Stephania A

Subjects
Toxicology. Poisons, RA1190-1270, Industrial hygiene. Industrial welfare, HD7260-7780.8
Abstract

Abstract Background Combustion generated particulate matter is deposited in the respiratory tract and pose a hazard to the lungs through their potential to cause oxidative stress and inflammation. We have previously shown that combustion of fuels and chlorinated hydrocarbons produce semiquinone-type radicals that are stabilized on particle surfaces (i.e. environmentally persistent free radicals; EPFRs). Because the composition and properties of actual combustion-generated particles are complex, heterogeneous in origin, and vary from day-to-day, we have chosen to use surrogate particle systems. In particular, we have chosen to use the radical of 2-monochlorophenol (MCP230) as the EPFR because we have previously shown that it forms a EPFR on Cu(II)O surfaces and catalyzes formation of PCDD/F. To understand the physicochemical properties responsible for the adverse pulmonary effects of combustion by-products, we have exposed human bronchial epithelial cells (BEAS-2B) to MCP230 or the CuO/silica substrate. Our general hypothesis was that the EPFR-containing particle would have greater toxicity than the substrate species. Results Exposure of BEAS-2B cells to our combustion generated particle systems significantly increased reactive oxygen species (ROS) generation and decreased cellular antioxidants resulting in cell death. Resveratrol treatment reversed the decline in cellular glutathione (GSH), glutathione peroxidase (GPx), and superoxide dismutase (SOD) levels for both types of combustion-generated particle systems. Conclusion The enhanced cytotoxicity upon exposure to MCP230 correlated with its ability to generate more cellular oxidative stress and concurrently reduce the antioxidant defenses of the epithelial cells (i.e. reduced GSH, SOD activity, and GPx). The EPFRs in MCP230 also seem to be of greater biological concern due to their ability to induce lipid peroxidation. These results are consistent with the oxidizing nature of the CuO/silica ultrafine particles and the reducing nature and prolonged environmental and biological lifetimes of the EPFRs in MCP230.

Published
2009
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35. Regular self-tests can put managers at the head of the class

Author

Cole, Richard B.

Subjects
Security services industry -- Management, Customer satisfaction -- Management, Business, Engineering and manufacturing industries, Law
Abstract

Security firm serving corporate clients should focus on improving customer satisfaction. To do this, security services should possess a clear understanding of the needs of the client as well as the strengths and weaknesses of their operations. Security firms can evaluate these elements by using routine service assessments. Such assessments should cover the key aspects of the security operations as well as the leadership abilities of top security personnel.

Published
1996

37. High resolution mass spectrometry for quantitative analysis and untargeted screening of algal toxins in mussels and passive samplers

Author

Zendong, Suzie Zita, Mccarron, Pearse, Herrenknecht, Christine, Sibat, Manoella, Amzil, Zouher, Cole, Richard B., Hess, Philipp, Zendong, Suzie Zita, Mccarron, Pearse, Herrenknecht, Christine, Sibat, Manoella, Amzil, Zouher, Cole, Richard B., and Hess, Philipp

Abstract

Measurement of marine algal toxins has traditionally focussed on shellfish monitoring while, over the last decade, passive sampling has been introduced as a complementary tool for exploratory studies. Since 2011, liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been adopted as the EU reference method (No.15/2011) for detection and quantitation of lipophilic toxins. Traditional LC-MS approaches have been based on low-resolution mass spectrometry (LRMS), however, advances in instrument platforms have led to a heightened interest in the use of high-resolution mass spectrometry (HRMS) for toxin detection. This work describes the use of HRMS in combination with passive sampling as a progressive approach to marine algal toxin surveys. Experiments focused on comparison of LRMS and HRMS for determination of a broad range of toxins in shellfish and passive samplers. Matrix effects are an important issue to address in LC-MS; therefore, this phenomenon was evaluated for mussels (Mytilus galloprovincialis) and passive samplers using LRMS (triple quadrupole) and HRMS (quadrupole time-of-flight and Orbitrap) instruments. Matrix-matched calibration solutions containing okadaic acid and dinophysistoxins, pectenotoxin, azaspiracids, yessotoxins, domoic acid, pinnatoxins, gymnodimine A and 13-desmethyl spirolide C were prepared. Similar matrix effects were observed on all instruments types. Most notably, there was ion enhancement for pectenotoxins, okadaic acid/dinophysistoxins on one hand, and ion suppression for yessotoxins on the other. Interestingly, the ion selected for quantitation of PTX2 also influenced the magnitude of matrix effects, with the sodium adduct typically exhibiting less susceptibility to matrix effects than the ammonium adduct. As expected, mussel as a biological matrix, quantitatively produced significantly more matrix effects than passive sampler extracts, irrespective of toxin. Sample dilution was demonstrated as an effective measure to reduce ma

Published
2015
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38. Le développement de méthode d’empreintes métabolomiques à haut débit et à ultra haute résolution pour le phénotypage métabolique et l’identification structurale de biomarqueurs

Author

Xue, Baiyi, Alves, Sandra, Tabet, Jean-Claude, Cole, Richard B., Paris, Alain, Junot, Christophe, Rathahao, Estelle, Ingénierie Procédés Aliments (GENIAL), Institut National de la Recherche Agronomique (INRA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-AgroParisTech-Conservatoire National des Arts et Métiers [CNAM] (CNAM), Chimie Structurale Organique et Biologique (CSOB), Institut Parisien de Chimie Moléculaire (IPCM), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Méthodologies d'Analyse de Risque Alimentaire (MET@RISK), Institut National de la Recherche Agronomique (INRA), Laboratoire d'Etude du Métabolisme des Médicaments (LEMM), Service de Pharmacologie et Immunoanalyse (SPI), Médicaments et Technologies pour la Santé (MTS), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Médicaments et Technologies pour la Santé (MTS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Conservatoire National des Arts et Métiers [CNAM] (CNAM), HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Médicaments et Technologies pour la Santé (MTS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), and ProdInra, Archive Ouverte

Subjects
[SDV] Life Sciences [q-bio], [SDV]Life Sciences [q-bio]
Abstract

Le développement de méthode d’empreintes métabolomiques à haut débit et à ultra haute résolution pour le phénotypage métabolique et l’identification structurale de biomarqueurs. 7. Journées Scientifiques du Réseau Français de Métabolomique et Fluxomique

Published
2013

39. Détection des métabolites urinaires par spectrométrie de masse à très haute résolution : comparaison entre les approches DI /ESI-FTICR et LC/ESI-LTQ-Orbitrap

Author

Xue, Baiyi, Alves, Sandra, Tabet, Jean-Claude, Cole, Richard B., Paris, Alain, Rathahao, Estelle, Junot, Christophe, Ingénierie Procédés Aliments (GENIAL), Institut National de la Recherche Agronomique (INRA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-AgroParisTech-Conservatoire National des Arts et Métiers [CNAM] (CNAM), Chimie Structurale Organique et Biologique (CSOB), Institut Parisien de Chimie Moléculaire (IPCM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Méthodologies d'Analyse de Risque Alimentaire (MET@RISK), Institut National de la Recherche Agronomique (INRA), Laboratoire d'Etude du Métabolisme des Médicaments (LEMM), Service de Pharmacologie et Immunoanalyse (SPI), Médicaments et Technologies pour la Santé (MTS), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Médicaments et Technologies pour la Santé (MTS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Ingénierie Procédés Aliments ( GENIAL ), Institut National de la Recherche Agronomique ( INRA ) -AgroParisTech-Conservatoire National des Arts et Métiers [CNAM] ( CNAM ), Chimie Structurale Organique et Biologique ( CSOB ), Institut Parisien de Chimie Moléculaire ( IPCM ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Méthodologies d'Analyse de Risque Alimentaire ( MET@RISK ), Institut National de la Recherche Agronomique ( INRA ), Laboratoire d'Etude du Métabolisme des Médicaments ( LEMM ), Service de Pharmacologie et Immunoanalyse ( SPI ), Département Médicaments et Technologies pour la Santé ( DMTS ), Direction de Recherche Fondamentale (CEA) ( DRF (CEA) ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) ( DRF (CEA) ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Département Médicaments et Technologies pour la Santé ( DMTS ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay, Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Médicaments et Technologies pour la Santé (MTS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Institut National de la Recherche Agronomique (INRA)-AgroParisTech-Conservatoire National des Arts et Métiers [CNAM] (CNAM), HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université (HESAM)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), and ProdInra, Archive Ouverte

Subjects
[SDV] Life Sciences [q-bio], [ SDV ] Life Sciences [q-bio], [SDV]Life Sciences [q-bio]
Abstract

Détection des métabolites urinaires par spectrométrie de masse à très haute résolution : comparaison entre les approches DI /ESI-FTICR et LC/ESI-LTQ-Orbitrap. 7. Journées Scientifiques du Réseau Français de Métabolomique et Fluxomique

Published
2013

43. What trends are shaping security's future?

Author

Cole, Richard B.

Subjects
Security services industry -- Forecasts and trends, Security guards -- Vocational guidance, Business, Engineering and manufacturing industries, Law
Abstract

Several trends have been observed in the security profession. One is the practice of companies in hiring unskilled people for entry-level security positions, which may be due to the shortage of skilled professionals. Another is the provision of computer-aided training which features simulations of security problems and resolutions. One of the most significant trends is the increasing identification of security professionals as either generalists or specialists.

Published
1998

46. Seeing beyond security

Author

Cole, Richard B.

Subjects
Security departments -- Management, Facility security -- Management, Security services industry -- Practice, Business, Engineering and manufacturing industries, Law
Abstract

A security manager must not limit himself to discharging the functions of the security department but must involve himself in the development of the organization. Thus, he must work toward integrating enforcement and compliance processes into the company's entire operation. He must present concrete evidence of his department's performance that will have a positive impact on the overall business.

Published
1995

48. MALDI-TOF mass signatures for differentiation of yeast species, strain grouping and monitoring of morphogenesis markers.

Author

Jiang Qian, Cutler, Jim E., Cole, Richard B., and Yang Cai

Subjects
YEAST, MORPHOGENESIS, MASS spectrometry, PRINCIPAL components analysis, CANDIDA albicans
Abstract

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) is demonstrated to be a potentially useful tool for the rapid identification of yeasts, the grouping of Candida albicans strains, and the monitoring of germ tube-specific markers. Co-crystallized with sinapinic acid as the MALDI matrix, intact yeast cells yielded a sufficient number of medium-sized ions (4–15 kDa) in MALDI mass spectra to provide “mass signatures” that were diagnostic of strain type. For most isolates, the mass signatures were affected by the growth medium, length of incubation and the cell preparation method. While the overall past success of this methodology for fungal cells has been relatively low compared to its application to bacteria, fixing the yeast cells in 50% methanol inactivated the cells, reduced cell aggregation in aqueous suspension solution, and more importantly, it significantly improved the mass signature quality. This simple but critical advance in sample treatment improved mass spectrometric signal-to-noise ratios and allowed the identification of yeasts by a mass signature approach. Under optimized conditions, Candida species ( C. albicans, C. glabrata, C. krusei, C. kefyr), Aspergillus species ( A. terreus, A. fumigatus, A. syndowii) and other yeast genera ( Cryptococcus neoformans, Saccharomyces cerevisiae and a Rhodotorula sp.) could be distinguished. Within the C. albicans species, several common ions in the m/z 5,000–10,000 range were apparent in the mass spectra of all tested strains. In addition to shared ions, the mass spectra of individual C. albicans strains permitted grouping of the strains. Principal component analysis (PCA) was employed to confirm spectral reproducibility and C. albicans strain grouping by mass signatures. Finally, C. albicans germ tubes produced MALDI-TOF mass signatures that differed from yeast forms of this species. This is a rapid, sensitive and simple method for identifying yeasts, grouping strains and following the morphogenesis of C. albicans. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Published
2008
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49. Liquid chromatography–electrospray tandem mass spectrometry investigations of fragmentation pathways of biliary 4,4′-methylenedianiline conjugates produced in rats.

Author

Kan Chen, Dugas, Tammy R., and Cole, Richard B.

Subjects
DIAMINODIPHENYLMETHANE, METABOLITES, GLUTATHIONE, GLYCINE, LIQUID chromatography, ELECTROSPRAY ionization mass spectrometry, LABORATORY rats
Abstract

4,4′-methylenedianiline (DAPM) is the main building block for production of 4,4′-methylenediphenyldiisocyanate that has been widely used in the manufacturing of polyurethane materials including medical devices. Although it was revealed that damage to biliary epithelial cells of the liver and common bile duct occurred upon acute exposure to DAPM, the exact mechanism of DAPM toxicity is not fully understood. Both phase I and II biotransformations of DAPM, some of which generate reactive intermediates, are characterized in detail by liquid chromatography electrospray tandem mass spectrometry. The two most prominent metabolites found in rat bile (M2 and M7) implicated glutathione, glucuronic acid, and glycine conjugations (phase II) following hydroxylation, and N-oxidation (phase I). Their decomposition pathways, as evidenced by MS n experiments, have been elucidated in detail. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Published
2008
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50. Identification of in vitro metabolites of JWH-015, an aminoalkylindole agonist for the peripheral cannabinoid receptor (CB2) by HPLC-MS/MS.

Author

Zhang, Qiang, Ma, Peng, Cole, Richard B., and Wang, Guangdi

Subjects
METABOLITES, INDOLE alkaloids, METABOLISM, CANNABINOIDS, RECEPTOR-ligand complexes, CHEMICAL agonists, MASS spectrometry, HYDROXYLATION
Abstract

The in vitro microsomal metabolism of JWH-015, a ligand that exhibits a high binding affinity at the peripheral cannabinoid receptor CB2, has been studied. A total of 22 metabolites were identified and structurally characterized. The metabolites are products of: 1) monohydroxylation on the naphthalene ring ( m/ z 344, M20 and M21), indole ring ( m/ z 344, M17 and M18), or the N-alkyl group ( m/ z 344, M14); 2) arene oxidation leading to dihydrodiols ( m/ z 362, M12 and M15); 3) dihydroxylation on the naphthalene ring ( m/ z 360, M7) or indole ring ( m/ z 360, M13), resulting from a combination of monohydroxylations on both the naphthalene and indole rings ( m/ z 360, M16), or a combination of monohydroxylations on the naphthalene ring and on the N-propyl group ( m/ z 360, M9); 4) trihydroxylation ( m/ z 378, M1, M3, M4, M6, and M10); 5) N-dealkylation ( m/ z 286, M19); 6) N-dealkylation and monohydroxylation on the naphthalene ring ( m/ z 302, M11); 7) N-dealkylation and dihydrodiol formation from arene oxidation ( m/ z 320, M2 and M5); 8) dehydrogenation after monohydroxylation on the N-alkyl group ( m/ z 326, M22); 9) dehydrogenation and monohydroxylation on the indole ring ( m/ z 342, M8). [ABSTRACT FROM AUTHOR]

Published
2006
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