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Felix Hernandez - One of the best experts on this subject based on the ideXlab platform.
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investigation of degradation products of cocaine and benzoylecgonine in the aquatic environment
Science of The Total Environment, 2013Co-Authors: Lubertus Bijlsma, Juan V Sancho, Maria Ibanez, C Boix, W M A Niessen, Felix HernandezAbstract:Abstract In this work, ultra-high-performance liquid chromatography (UHPLC) coupled to a hybrid quadrupole time-of-flight mass spectrometer (QTOF MS) has allowed the discovery and elucidation of degradation products of cocaine and its main metabolite benzoylecgonine (BE) in water. Spiked surface water was subjected to hydrolysis, chlorination and photo-degradation (both ultraviolet irradiation and simulated sunlight). After degradation of cocaine, up to sixteen compounds were detected and tentatively identified (1 resulting from hydrolysis; 8 from chlorination; 7 from photo-degradation), three of which are well known cocaine metabolites (BE, norbenzoylecgonine and Norcocaine). Regarding BE degradation, up to ten compounds were found (3 from chlorination; 7 from photo-degradation), including one known metabolite (norbenzoylecgonine). Since reference standards were available for the major metabolites, they could be confirmed using information on retention time and fragment ions. The other degradates resulted from chlorination, dealkylation, hydroxylation and nitration, or from a combination of these processes. Several influent and effluent sewage water, and surface water samples were then screened for the identified compounds (known and unknown) using UHPLC–tandem MS with triple quadrupole. BE, Norcocaine and norbenzoylecgonine were identified in these samples as major metabolites. Four previously unreported degradates were also found in some of the samples under study, illustrating the usefulness and applicability of the degradation experiments performed in this work.
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simultaneous ultra high pressure liquid chromatography tandem mass spectrometry determination of amphetamine and amphetamine like stimulants cocaine and its metabolites and a cannabis metabolite in surface water and urban wastewater
Journal of Chromatography A, 2009Co-Authors: Lubertus Bijlsma, Juan V Sancho, E Pitarch, Maria Ibanez, Felix HernandezAbstract:Abstract An ultra-high-pressure liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method has been developed for the simultaneous quantification and confirmation of 11 basic/acidic illicit drugs and relevant metabolites in surface and urban wastewater at ng/L levels. The sample pre-treatment consisted of a solid-phase extraction using Oasis MCX cartridges. Analyte deuterated compounds were used as surrogate internal standards (except for norbenzoylecgonine and Norcocaine) to compensate for possible errors resulting from matrix effects and those associated to the sample preparation procedure. After SPE enrichment, the selected drugs were separated within 6 min under UHPLC optimized conditions. To efficiently combine UHPLC with MS/MS, a fast-acquisition triple quadrupole mass analyzer (TQD from Waters) in positive-ion mode (ESI+) was used. The excellent selectivity and sensitivity of the TQD analyzer in selected reaction monitoring mode allowed quantification and reliable identification at the LOQ levels. Satisfactory recoveries (70–120%) and precision (RSD 99%) for low levels of illicit drugs in water, but some difficulties were observed when high drug levels were present in wastewaters.
Lubertus Bijlsma - One of the best experts on this subject based on the ideXlab platform.
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investigation of degradation products of cocaine and benzoylecgonine in the aquatic environment
Science of The Total Environment, 2013Co-Authors: Lubertus Bijlsma, Juan V Sancho, Maria Ibanez, C Boix, W M A Niessen, Felix HernandezAbstract:Abstract In this work, ultra-high-performance liquid chromatography (UHPLC) coupled to a hybrid quadrupole time-of-flight mass spectrometer (QTOF MS) has allowed the discovery and elucidation of degradation products of cocaine and its main metabolite benzoylecgonine (BE) in water. Spiked surface water was subjected to hydrolysis, chlorination and photo-degradation (both ultraviolet irradiation and simulated sunlight). After degradation of cocaine, up to sixteen compounds were detected and tentatively identified (1 resulting from hydrolysis; 8 from chlorination; 7 from photo-degradation), three of which are well known cocaine metabolites (BE, norbenzoylecgonine and Norcocaine). Regarding BE degradation, up to ten compounds were found (3 from chlorination; 7 from photo-degradation), including one known metabolite (norbenzoylecgonine). Since reference standards were available for the major metabolites, they could be confirmed using information on retention time and fragment ions. The other degradates resulted from chlorination, dealkylation, hydroxylation and nitration, or from a combination of these processes. Several influent and effluent sewage water, and surface water samples were then screened for the identified compounds (known and unknown) using UHPLC–tandem MS with triple quadrupole. BE, Norcocaine and norbenzoylecgonine were identified in these samples as major metabolites. Four previously unreported degradates were also found in some of the samples under study, illustrating the usefulness and applicability of the degradation experiments performed in this work.
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simultaneous ultra high pressure liquid chromatography tandem mass spectrometry determination of amphetamine and amphetamine like stimulants cocaine and its metabolites and a cannabis metabolite in surface water and urban wastewater
Journal of Chromatography A, 2009Co-Authors: Lubertus Bijlsma, Juan V Sancho, E Pitarch, Maria Ibanez, Felix HernandezAbstract:Abstract An ultra-high-pressure liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) method has been developed for the simultaneous quantification and confirmation of 11 basic/acidic illicit drugs and relevant metabolites in surface and urban wastewater at ng/L levels. The sample pre-treatment consisted of a solid-phase extraction using Oasis MCX cartridges. Analyte deuterated compounds were used as surrogate internal standards (except for norbenzoylecgonine and Norcocaine) to compensate for possible errors resulting from matrix effects and those associated to the sample preparation procedure. After SPE enrichment, the selected drugs were separated within 6 min under UHPLC optimized conditions. To efficiently combine UHPLC with MS/MS, a fast-acquisition triple quadrupole mass analyzer (TQD from Waters) in positive-ion mode (ESI+) was used. The excellent selectivity and sensitivity of the TQD analyzer in selected reaction monitoring mode allowed quantification and reliable identification at the LOQ levels. Satisfactory recoveries (70–120%) and precision (RSD 99%) for low levels of illicit drugs in water, but some difficulties were observed when high drug levels were present in wastewaters.
Berend Mets - One of the best experts on this subject based on the ideXlab platform.
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Cocaine, Norcocaine, ecgonine methylester and benzoylecgonine pharmacokinetics in the rat
Life Sciences, 1999Co-Authors: Berend Mets, E. Soo, J. Diaz, Subhash C. JamdarAbstract:Abstract We have compared the pharmacokinetics of bolus dose cocaine administration with that of its three most important metabolites; Norcocaine, ecgonine methylester, and benzoylecgonine and assessed whether kinetics are dose dependent at two equimolar doses equivalent to cocaine hydrochloride 2.5 and 5 mg kg respectively. Forty-nine male Sprague-Dawley rats were randomly divided into 8 groups to receive iv either high (14.7 umol kg ) (HI) or low (7.3 umol kg ) (LO) bolus doses of cocaine or one of its metabolites. Arterial blood samples for cocaine and metabolite analysis were taken repetitively over the next 3 h. Equimolar bolus doses of these congeners showed biexponential plasma concentration decay curves which were fitted to a two compartment model and subjected to noncompartmental analysis. The plasma concentration time profiles were significantly different for the HI and LO doses administered for each congener. The elimination half-lives of cocaine and Norcocaine were similar (28–33 min), that for ecgonine methylester (60–71 min) was approximately twice this and for benzoylecgonine was 40–44 min. Cocaine clearance (155–158 ml/kg/min) was found to be in the range found in other rat studies. Ecgonine methylester clearance and benzoylecgonine clearance were found to be one quarter and one eighth of this value respectively. The pharmacokinetic profile of these congeners was not dose dependent when the two doses administered were compared.
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A validated stable isotope dilution liquid chromatography tandem mass spectrometry assay for the trace analysis of cocaine and its major metabolites in plasma.
Analytical Chemistry, 1999Co-Authors: G. Singh, Berend Mets, V. Arora, P. T. Fenn, Ian A. BlairAbstract:A validated method has been developed for the simultaneous quantitation of cocaine and its major metabolites (ecgonine methyl ester, benzoylecgonine, and Norcocaine) in rat plasma. The method is based upon the use of stable isotope dilution liquid chromatography/atmospheric pressure chemical ionization/tandem mass spectrometry. Previously reported methods do not have the sensitivity and specificity that can be attained with this method. Plasma samples required no cleanup apart from protein precipitation, and no derivatization was required. Selected reaction monitoring was performed on the transitions of m/z 200 to m/z 182 (ecgonine methyl ester), m/z 290 to m/z 168 (benzoylecgonine), m/z 304 to m/z 182 (cocaine), and m/z 290 to m/z 168 (Norcocaine). The standard curves were linear over the range from 2 ng/mL (benzoylecgonine, cocaine, and Norcocaine) or 5 ng/mL (ecgonine methyl ester) to 1000 ng/mL in rat plasma. The lower limit of quantitation (LLQ) for benzoylecgonine, cocaine, and Norcocaine was 2 ng/m...
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determination of cocaine Norcocaine benzoylecgonine and ecgonine methyl ester in rat plasma by high performance liquid chromatography with ultraviolet detection
Journal of Chromatography B: Biomedical Sciences and Applications, 1996Co-Authors: Laszlo Virag, Berend Mets, Subhash C. JamdarAbstract:An isocratic high-performance liquid chromatographic method with ultraviolet detection at 235 nm is described for the determination of cocaine and its metabolites benzoylecgonine, Norcocaine and ecgonine methyl ester in rat plasma, collected during toxicity studies. Following simultaneous solid-phase extraction of all analytes and the internal standard tropacocaine, cocaine, benzoylecgonine and Norcocaine were separated on a C18 column. Ecgonine methyl ester and cocaine were separated on coupled cyanopropyl and silica columns, following derivatization of ecgonine methyl ester to p-fluorococaine. The extraction efficiencies of these compounds from plasma ranged from 78 to 87%, while the limits of detection ranged from 35 to 90 ng/ml. The assay was linear from 300 to 5000 ng/ml, and the within-day precision 2 to 8% over this concentration range.
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The effects of inhibition of plasma cholinesterase and hepatic microsomal enzyme activity on cocaine, benzoylecgonine, ecgonine methyl ester, and Norcocaine blood levels in pigs.
The Journal of laboratory and clinical medicine, 1992Co-Authors: J. R. Kambam, Berend Mets, R. Hickman, Piotr K. Janicki, Michael F. M. James, B. Fuller, R. KirschAbstract:We measured the blood levels of cocaine and its three major metabolites, benzoylecgonine, ecgonine methyl ester, and Norcocaine, in three groups of male pigs weighing about 26 kg (25.75 +/- 0.25 kg) to determine the effects of inhibition of plasma cholinesterase and hepatic microsomal enzyme activity on cocaine metabolism. In addition, systemic elimination half-life, volume of distribution, and clearance of cocaine were calculated for the three groups. Group 1 pigs (n = 4) were pretreated with normal saline solution, group 2 pigs (n = 4) were pretreated with tetraisopropyl pyrophosphoramide, a specific plasma cholinesterase inhibitor, and group 3 pigs (n = 4) were pretreated with cimetidine, a hepatic microsomal enzyme inhibitor, all administered intramuscularly. Pigs were anesthetized with intravenous sodium thiopental; a carotid arterial cannula and an external jugular catheter were then inserted for the administration of cocaine and for blood sampling. Forty-five minutes later, when pigs were again completely awake, cocaine 3 mg/kg was given intravenously. Arterial blood samples were collected for the analysis of cocaine and cocaine metabolite levels just before and at 5, 10, 15, 30, 45, 60, 120, 180, and 1440 minutes after the administration of cocaine. Cocaine and cocaine metabolite blood levels were analyzed with high-pressure liquid chromatography methods and plasma cholinesterase activity was measured with a colorimetric method. The blood levels of cocaine and cocaine metabolites were significantly different among the three groups (p less than 0.05, analysis of variance). Statistically significant differences in half-life, volume of distribution and clearance were also seen among the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Lilian De Lima Feltraco Lizot - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of cocaine ecgonine methyl ester benzoylecgonine cocaethylene and Norcocaine in dried blood spots by ultra performance liquid chromatography coupled to tandem mass spectrometry
Forensic Science International, 2019Co-Authors: Lilian De Lima Feltraco Lizot, Anne Caroline Cezimbra Da Silva, Marcos Frank Bastiani, Roberta Zilles Hahn, Rachel Bulcao, Magda Susana Perassolo, Marina Venzon Antunes, Rafael LindenAbstract:Abstract Cocaine (COC) is one of the most widely abused drugs in the world and its sensitive and its reliable measurement in blood is of great importance in the field of forensic and clinical toxicology. Additionally, the determination of COC metabolites such as benzoylecgonine (BZE), cocaethylene (CE), ecgonine methyl ester (EME), and Norcocaine (NCOC) are also of complementary diagnostic value. The quantification of COC and metabolites in dried blood spots (DBS) may be an alternative to conventional collection methods with several advantages, including easier, on-site, collection, transportation and storage. In this study, we present a simple and comprehensively validated UPLC–MS/MS assay to measured COC, BZE, EME, NCOC and CE in DBS. The evaluated assay was linear from 5–500 ng mL−1. Precision assays presented CV% of 1.27–6.82, and accuracy in the range of 97–113.78%. Low haematocrit values had a negative impact in the assay accuracy. COC, BE, NCOC and CE measurements can be made reliably in DBS stored for 14 days at room temperature, as well as at −20 °C and 45 °C. All evaluated compounds can be measured in DBS maintained at −20 °C for 14 days. DBS sampling can be used for the clinical evaluation of the exposure to COC, being an alternative for collection, short-term storage and transportation of blood at room and high temperatures.
Gideon Koren - One of the best experts on this subject based on the ideXlab platform.
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Norcocaine in human hair as a biomarker of heavy cocaine use in a high risk population
Forensic Science International, 2014Co-Authors: S Poon, Paula Walasek, Joey Gareri, Gideon KorenAbstract:In hair analysis, cocaine (COC) and its metabolites have been studied relatively extensively with a consistent focus of distinguishing active drug use and excluding external contamination. Although quantitative cut-offs using major metabolite, benzolecgonine (BE), in hair have been proposed to distinguish likely active use from passive exposure, exogenously formed BE may result in false positive tests. Hence, the presence of less commonly detected COC metabolite, Norcocaine (NCOC), may be useful in increasing certainty of illicit COC use and evaluating likelihood of environmental contamination. The objective of the present study was to observe the pattern of NCOC detection in a clinical population of suspected users and evaluate the possible role of NCOC in distinguishing systemic exposure from external contamination to COC and assessing intensity of cocaine use. Hair samples collected between January 2011 and May 2013 from the Motherisk Laboratory were analyzed by GC-MS for the presence of COC, BE, and NCOC. NCOC positivity rates (%) for various COC concentration ranges as well as sensitivity, specificity, positive predictive value, and negative predictive values of NCOC as a biomarker of different COC use profiles was calculated. The rate of NCOC positivity (%) within COC concentration ranges (ng/mg) 0.13-0.4 (above LOD, below LOQ), 0.4-3, 3-6, 6-10, 10-14, >14 were 0.26, 4.15, 29.63, 55.85, 80.37, and 94.02, respectively; p<0.0001 for all positivity comparisons between ranges. These results were used to determine a COC cut-off concentration for differing levels of COC use. The presence of NCOC above the LOD of 0.13 ng/mg predicted COC concentrations exceeding 14.00 ng/mg, with sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 94.0%, 87.9%, 41.5%, and 99.4%, respectively. The presence NCOC above the LOD of 0.13 ng/mg predicted COC concentrations exceeding the 75th percentile, with sensitivity, specificity, PPV, and NPV of 76.6%, 94.7%, 74.7%, and 95.2%, respectively. Despite an inability to definitively rule out external contamination, the presence of NCOC in hair is strongly associated with elevated COC levels and performs as a highly specific surrogate marker for frequent/intensive cocaine use and highly sensitive marker for intensive/daily use of cocaine.
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simultaneous detection of seventeen drugs of abuse and metabolites in hair using solid phase micro extraction spme with gc ms
Forensic Science International, 2012Co-Authors: Katarina Aleksa, Paula Walasek, Netta Fulga, Bhushan Kapur, Joey Gareri, Gideon KorenAbstract:Abstract Introduction The analysis of pediatric and adult hair is a useful non-invasive biomarker to effectively detect long term exposure to various xenobiotics, specifically drugs of abuse such as cocaine, opiates and amphetamines. Very often individuals are using, or are exposed to multiple drugs simultaneously and therefore it is important to be able to detect them in the same analysis. We have developed a sensitive and specific solid phase micro extraction (SPME) coupled with gas chromatography mass spectrometry (GC/MS) to detect 17 different analytes in hair using a single extraction method. Method Five milligrams of hair is extracted overnight, subjected to solid phase extraction (SPE) and then to SPME-GC/MS. The aimed analytes include amphetamine, methamphetamine, MDA, MDMA, cocaine, benzoylecognine, Norcocaine, cocaethylene, methadone, codeine, morphine, 6-AM, oxycodone, oxymorphone, hydrocodone, hydromorphone and meperidone. Results The following are the LOD of the various drugs: 0.2 ng/mg hair for amphetamine, methamphetamine, MDA, MDMA, morphine, codeine, 6-AM, oxycodone, oxymorphone, hydromorphone, hydrocodone, meperidine and 0.13 ng/mg hair for cocaine, benzoylecognine, cocaethylene, Norcocaine and methadone. Conclusion This GC/MS method is sensitive and specific to detect the presence of these 17 analytes in as little as 5 mg of hair and is especially useful for newborn and child hair analysis where the amount of hair is often very limited.
