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Xiong J, Wei X, Shen X, Zhu W, Yi S, Huang C. Synthesis of molecularly-imprinted polymers towards a group of amphetamine-type stimulants by reflux precipitation polymerization with a pseudo template. J Chromatogr A 2023; 1688:463738. [PMID: 36574747 DOI: 10.1016/j.chroma.2022.463738] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 12/11/2022] [Accepted: 12/20/2022] [Indexed: 12/26/2022]
Abstract
Determination of amphetamine-type drugs (ATSs) in urine and wastewater is a simplified approach for the widespread monitoring of ATSs abuse. To improve the sensitivity of the analytical methods, molecularly imprinted polymers (MIPs) based solid-phase extraction (SPE) pretreatment attracted great attention in this field. Generally, smaller particle sizes and more uniform morphology of the MIPs could provide higher detection sensitivity. Our previous works showed reflux precipitation polymerization (RPP) is a method for synthesizing monodispersed MIPs with small particle size. However, synthesis of uniform spherical MIPs towards a group of targets has never been reported. Therefore, in the present work, MIPs towards a group of ATSs were synthesized via RPP with a pseudo template for the first time. After screening potential pseudo-templates, N-methylphenylethylamine (MPEA) was selected as the optimal pseudo-template. MPEA-MIPs were characterized by scanning electron microscope (SEM), FT-IR spectroscopy and X-ray photoelectron spectroscopy (XPS) spectra. Adsorption isotherms, adsorption kinetics and selectivity were evaluated, and the experimental results indicated that the MPEA-MIPs possessed good selectivity and adsorption property towards ATSs. After optimization of the MIP-SPE procedure, the MIP-SPE cartridges were then coupled with liquid chromatography and tandem mass spectrometry (LC-MS/MS) for determination of ATSs. The evaluation results showed that MIP-SPE-LC-MS/MS displayed good linearity (R2 >0.991) in the linear range (1.0-50.0 µg/L for urine and 0.5-50.0 µg/L for wastewater), and low matrix effect (85-112%). The limit of detection (LOD) was 0.05 -0.29 µg/L, and the accuracy (85-115%) and repeatability (RSD ≤ 15%) were satisfactory at low, medium and high concentrations. To the best of our knowledge, this is the first time that dummy MIPs towards a group of ATSs were synthesized by RPP polymerization, which showed great potential for the detection of ATSs in urine and wastewater.
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Affiliation(s)
- Jianhua Xiong
- Department of Forensic Medicine, Huazhong University of Science and Technology, Hangkong Road #13, Wuhan, Hubei 430030, China
| | - Xiangting Wei
- Department of Forensic Medicine, Huazhong University of Science and Technology, Hangkong Road #13, Wuhan, Hubei 430030, China
| | - Xiantao Shen
- State Key Laboratory of Environment Health (Incubation), Key Laboratory of Environment and Health, Ministry of Education, Key Laboratory of Environment and Health (Wuhan), Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, #13 Hangkong Road, Wuhan, Hubei, 430030, China
| | - Weiwei Zhu
- Department of Forensic Medicine, Huazhong University of Science and Technology, Hangkong Road #13, Wuhan, Hubei 430030, China
| | - Shaohua Yi
- Department of Forensic Medicine, Huazhong University of Science and Technology, Hangkong Road #13, Wuhan, Hubei 430030, China.
| | - Chuixiu Huang
- Department of Forensic Medicine, Huazhong University of Science and Technology, Hangkong Road #13, Wuhan, Hubei 430030, China.
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2
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Cocaine use in individuals with schizophrenia: impact on doses of discharge antipsychotic medications. J Addict Med 2016; 9:177-80. [PMID: 25700142 DOI: 10.1097/adm.0000000000000110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Despite the high prevalence of cocaine use disorder in schizophrenia, the impact of cocaine on antipsychotic requirement has not been studied in this population. The aim of this study was to evaluate the effect of cocaine on doses of antipsychotic medication prescribed during periods of acute exacerbation of psychotic symptoms in individuals with schizophrenia. METHODS We reviewed the medical records of individuals with schizophrenia discharged from hospitals between 2008 and 2012. Student t tests and linear regression were used to compare doses of discharge antipsychotic medications (in chlorpromazine equivalents) between individuals with schizophrenia with cocaine positive urine drug test results (n = 180; age 42.71 ± 10.03 years) and individuals with schizophrenia with negative urine drug test results (n = 3194; age 38.49 ± 12.86 years). RESULTS Unadjusted analysis revealed that individuals with schizophrenia who tested positive for cocaine were discharged on lower doses of antipsychotic medication compared with those who tested negative (449.88 ± 2.12 vs 515.47 ± 2.16; P = 0.021). However, after adjusting for age, sex, race, and length of stay, the 2 groups did not differ on doses of discharge antipsychotic medication (geometric mean difference 7.41; CI: 7.62-12.30; P = 0.703). CONCLUSIONS Our preliminary result suggests that cocaine use does not impact significantly on the doses of antipsychotic medication prescribed during periods of acute exacerbation of psychosis in schizophrenia and individuals with schizophrenia with comorbid cocaine use disorder may require similar doses of antipsychotic medication as those without cocaine use disorder.
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Hospital length of stay in individuals with schizophrenia with and without cocaine-positive urine drug screens at hospital admission. J Nerv Ment Dis 2015; 203:33-6. [PMID: 25489749 DOI: 10.1097/nmd.0000000000000231] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Despite the high prevalence of cocaine use disorder (CUD) in individuals with schizophrenia, current understanding of the effect of cocaine on psychiatric hospital length of stay (LOS) in individuals with schizophrenia is limited. We therefore retrospectively examined the medical records of 5106 hospital admissions due to exacerbation of schizophrenia. Linear regression and t-test were used to compare LOS between individuals with schizophrenia with cocaine-positive urine drug test results and those with negative test results. Individuals with schizophrenia who were also positive for cocaine had shorter LOS from both unadjusted (geometric mean LOS, 8.07 ± 1.92 vs. 11.83 ± 1.83 days; p < 0.001) and adjusted (β = 0.69; confidence interval, 0.63-0.76; p < 0.001) analyses. Our results suggest that individuals with schizophrenia who also have comorbid CUD may require shorter inpatient treatment during periods of exacerbation of symptoms. Replication of this finding has relevance in treatment planning and resource allocation for the subpopulation of individuals with schizophrenia who also have stimulant use disorders.
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Rana S, Garg RK, Singla A. Rapid analysis of urinary opiates using fast gas chromatography–mass spectrometry and hydrogen as a carrier gas. EGYPTIAN JOURNAL OF FORENSIC SCIENCES 2014. [DOI: 10.1016/j.ejfs.2014.03.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Beck O, Carlsson S, Tusic M, Olsson R, Franzen L, Hulten P. Laboratory and clinical evaluation of on-site urine drug testing. Scandinavian Journal of Clinical and Laboratory Investigation 2014; 74:681-6. [DOI: 10.3109/00365513.2014.939995] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Olof Beck
- Department of Laboratory Medicine, Section of Clinical Pharmacology, Karolinska Institutet,
Stockholm, Sweden
| | | | - Marinela Tusic
- The Swedish Poisons Information Centre,
Stockholm, Sweden
| | | | - Lisa Franzen
- The Swedish Poisons Information Centre,
Stockholm, Sweden
| | - Peter Hulten
- The Swedish Poisons Information Centre,
Stockholm, Sweden
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Abstract
Opioids are some of the most commonly prescribed and abused drugs around the world. Primarily used for anesthesia or pain management, other opioids can also be used in the treatment of opioid addiction. Given these facts, clinicians often randomly test or monitor their patients to determine compliance or abstinence from these drugs via immunoassay methods. When a positive screen is obtained, a confirmatory assay is carried out and although the gold standard has been GC–MS, LC–MS/MS is fast becoming a valid and popular alternative. This review will discuss opioids, the complex metabolic pathways, the measurement of these drugs, the challenges involved and, finally, will describe some LC–MS/MS methods published from 2003 until 2013.
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Iwamuro Y, Iio-Ishimaru R, Chinaka S, Takayama N, Hayakawa K. Analysis of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid and its glucuronide in urine by capillary electrophoresis/mass spectrometry. Biomed Chromatogr 2012; 26:1452-6. [DOI: 10.1002/bmc.2719] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 01/08/2012] [Accepted: 01/09/2012] [Indexed: 11/06/2022]
Affiliation(s)
- Yoshiaki Iwamuro
- Forensic Science Laboratory; Ishikawa Prefectural Police Headquarters; 1-1 Kuratsuki; Kanazawa; 920-8553; Japan
| | - Reiko Iio-Ishimaru
- Forensic Science Laboratory; Ishikawa Prefectural Police Headquarters; 1-1 Kuratsuki; Kanazawa; 920-8553; Japan
| | - Satoshi Chinaka
- Forensic Science Laboratory; Ishikawa Prefectural Police Headquarters; 1-1 Kuratsuki; Kanazawa; 920-8553; Japan
| | - Nariaki Takayama
- Forensic Science Laboratory; Ishikawa Prefectural Police Headquarters; 1-1 Kuratsuki; Kanazawa; 920-8553; Japan
| | - Kazuichi Hayakawa
- Institute of Medical, Pharmaceutical and Health Sciences; Kanazawa University; Kakuma-machi; Kanazawa; 920-1192; Japan
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Urine analysis of 3,4-methylenedioxypyrovalerone in opioid-dependent patients by gas chromatography-mass spectrometry. Ther Drug Monit 2011; 33:257-63. [PMID: 21240056 DOI: 10.1097/ftd.0b013e318208b693] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A gas chromatography-mass spectrometry (GCMS) procedure was developed for the quantitative analysis of the new designer drug methylenedioxypyrovalerone (MDPV) in urine together with the common stimulants amphetamine, methamphetamine, and methylenedioxymethamphetamine (MDMA). The procedure involved electron ionization (EI) GCMS in the selected ion monitoring (SIM) mode after liquid-liquid extraction with toluene and derivatization with heptafluorobutyric acid anhydride. All MDPV findings were confirmed by positive chemical ionization GCMS in SIM mode. Positive chemical ionization-GCMS allowed the protonated molecule M+H+ m/z 276 to be used as a target ion with 3 abundant fragments as qualifier ions. By electron ionization-GCMS, the limit of quantification (LOQ) for MDPV was 0.02 mg/L; and for amphetamine, methamphetamine, and MDMA, the LOQ was 0.05 mg/L. The method was applied to monitoring urine samples from opioid-dependent patients undergoing opioid substitution treatment. Nine of the 34 urine samples (26%) analyzed were MDPV positive by the GCMS procedure. The positive samples were obtained from 2 female and 7 male patients with a mean age of 31 years. The median (range) MDPV concentration was 0.16 mg/L (0.04-3.9 mg/L) based on the 7 samples for which a numeric value was obtained, whereas the concentration was below the LOQ but above the limit of detection in 2 samples. The method revealed amphetamine in approximately 40% of the cases, and there was no statistical difference between the MDPV-positive and MDPV-negative groups. Urine amphetamine concentrations were on average 10 times higher than those of MDPV. The opioid-dependent patients used MDPV mainly as a substitute for amphetamine, judging from the laboratory findings of this study and the information from our patients.
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Aturki Z, D'Orazio G, Rocco A, Bortolotti F, Gottardo R, Tagliaro F, Fanali S. CEC-ESI ion trap MS of multiple drugs of abuse. Electrophoresis 2010; 31:1256-1263. [PMID: 20209571 DOI: 10.1002/elps.200900629] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This article describes a method for the separation and determination of nine drugs of abuse in human urine, including amphetamines, cocaine, codeine, heroin and morphine. This method was based on SPE on a strong cation exchange cartridge followed by CEC-MS. The CEC experiments were performed in fused silica capillaries (100 microm x 30 cm) packed with a 3 mum cyano derivatized silica stationary phase. A laboratory-made liquid junction interface was used for CEC-MS coupling. The outlet capillary column was connected with an emitter tip that was positioned in front of the MS orifice. A stable electrospray was produced at nanoliter per minute flow rates applying a hydrostatic pressure (few kPa) to the interface. The coupling of packed CEC columns with mass spectrometer as detector, using a liquid junction interface, provided several advantages such as better sensitivity, low dead volume and independent control of the conditions used for CEC separation and ESI analysis. For this purpose, preliminary experiments were carried out in CEC-UV to optimize the proper mobile phase for CEC analysis. Good separation efficiency was achieved for almost all compounds, using a mixture containing ACN and 25 mM ammonium formate buffer at pH 3 (30:70, v/v), as mobile phase and applying a voltage of 12 kV. ESI ion-trap MS detection was performed in the positive ionization mode. A spray liquid, composed by methanol-water (80:20, v/v) and 1% formic acid, was delivered at a nano-flow rate of approximately 200 nL/min. Under optimized CEC-ESI-MS conditions, separation of the investigated drugs was performed within 13 min. CEC-MS and CEC-MS(2) spectra were obtained by providing the unambiguous confirmation of these drugs in urine samples. Method precision was determined with RSDs values <or=3.3% for retention times and <or=16.3% for peak areas in both intra-day and day-to-day experiments. LODs were established between 0.78 and 3.12 ng/mL for all compounds. Linearity was satisfactory in the concentration range of interest for all compounds (r(2)>or=0.995). The developed CEC-MS method was then applied to the analysis of drugs of abuse in spiked urine samples, obtaining recovery data in the range 80-95%.
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Affiliation(s)
- Zeineb Aturki
- Istituto di Metodologie Chimiche, Consiglio Nazionale delle Ricerche, Area della Ricerca di Roma, Monterotondo Scalo, Rome, Italy
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Goldberger BA, Chronister CW, Merves ML. Quantitation of opioids in blood and urine using gas chromatography-mass spectrometry (GC-MS). Methods Mol Biol 2010; 603:399-410. [PMID: 20077092 DOI: 10.1007/978-1-60761-459-3_39] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The opioid and 6-acetylmorphine assays utilize gas chromatography-mass spectrometry (GC-MS) for the analysis of morphine, codeine, hydromorphone, hydrocodone, and 6-acetylmorphine in blood and urine. The specimens are fortified with deuterated internal standard and a five-point calibration curve is constructed. Specimens are extracted by mixed-mode solid phase extraction. The morphine, codeine, hydromorphone, hydrocodone, and 6-acetylmorphine extracts are derivatized with N-methyl-bis(trifluoroacetamide) (MBTFA) producing trifluoroacetyl derivatives. The final extracts are then analyzed using selected ion monitoring GC-MS.
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Affiliation(s)
- Bruce A Goldberger
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, FL, USA
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11
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Gallardo E, Barroso M, Queiroz JA. LC-MS: a powerful tool in workplace drug testing. Drug Test Anal 2009; 1:109-15. [DOI: 10.1002/dta.26] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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12
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Wako E, LeDoux D, Mitsumori L, Aldea GS. The Emerging Epidemic of Methamphetamine-Induced Aortic Dissections. J Card Surg 2007; 22:390-3. [PMID: 17803574 DOI: 10.1111/j.1540-8191.2007.00432.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The clinical presentation, treatment, and outcomes of six consecutive patients presenting with acute aortic dissection secondary to hypertensive crises from methamphetamine use is described. Data were obtained prospectively from the expanded STS clinical database of the division of cardiothoracic surgery at the University of Washington, but reviewed in a retrospective fashion. These patients represent 5.5% of all patients diagnosed and treated for aortic dissection in the same time period (6/109) and 20% of all patients with aortic dissection under the age of 50 years (6/30). We conclude that young patients (<age 50 years old) presenting with acute aortic dissections should be routinely tested for methamphetamine. Positive urine tests should be confirmed with chromatography-mass spectrometry (GC-MS). Beta and alpha blockers should be used instead of the more typical beta blockade alone. We recommend the addition and documentation of intense, long-term drug rehabilitation program along with routine periodic clinical and radiographic follow-up to prevent secondary aneurysmal dilation of remaining pathological aorta.
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Affiliation(s)
- Elizabeth Wako
- Division of Cardiothoracic Surgery, University of Washington, AA-115 Health Sciences Building, 1959 NE Pacific Street, Seattle, Washington 98195-6310, USA
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Gustavsson E, Andersson M, Stephanson N, Beck O. Validation of direct injection electrospray LC-MS/MS for confirmation of opiates in urine drug testing. JOURNAL OF MASS SPECTROMETRY : JMS 2007; 42:881-9. [PMID: 17535017 DOI: 10.1002/jms.1219] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
A method based on the direct injection of diluted urine for the identification and quantification of morphine, morphine-3-glucuronide, morphine-6-glucuronide, codeine, codeine-6-glucuronide, ethylmorphine, ethylmorphine-6-glucuronide and 6-acetylmorphine (6AM) in human urine by electrospray ionisation liquid chromatography-tandem mass spectrometry was validated for use as a confirmation procedure in urine drug testing. Four deuterium labelled analogues were used as internal standards: morphine-3-glucuronide-D3, morphine-D3, codeine-D3 and 6AM-D3. Twenty microlitre aliquots of urine were mixed with 80 mul of the internal standard solution in autosampler vials and 10 mul was injected. The chromatographic system consisted of a 2.0 x 100 mm C18 column and the gradient elution buffers used acetonitrile and 25 mmol/l formic acid. Two product ions produced from the protonated molecular ions were monitored in the selected reaction monitoring mode. The intra- and inter-assay variability (coefficient of variation) was below 10% at higher levels for all analytes, but at the reporting limits the variation was above 20% for 6AM, morphine-3-glucuronide and codeine-6-glucuronide. Ion suppression occurred early after injection but did not affect the identification and quantification of the analytes in authentic samples. The method was further validated by comparison with a reference gas chromatographic-mass spectrometric method using authentic urine samples. The two methods agreed almost completely (99%) regarding the identified analytes, but for the quantitative results there were slightly lower levels when measuring glucuronides directly as compared to total determination after hydrolysis by gas chromatography-mass spectrometry. We conclude that the presented liquid chromatographic-tandem mass spectrometric method is robust and reliable, and suitable for use as a confirmation method in urine drug testing for opiates
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Affiliation(s)
- E Gustavsson
- Department of Medicine, Division of Clinical Pharmacology, Karolinska University Hospital, SE-17176 Stockholm, Sweden
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Abstract
The illicit manufacturing and use of methamphetamine continues to be a significant and growing problem in the United States. Children are often found in homes where this activity is occurring and are affected by it on many levels. This article will provide background information on the manufacturing of methamphetamine, including classes of chemicals involved; hazards inherent to the manufacturing process and its effects on those living in a clandestine laboratory; and the approach to children found in these homes and their medical care. The focus will be on care in the acute settings with the introduction of a protocol for evaluation and follow-up of these patients.
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Affiliation(s)
- Penny Grant
- Child Advocacy and Protection Program, Dartmouth-Hitchcock Medical Center, Lebanon, NH, USA.
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15
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Grant P. Evaluation of Children Removed From a Clandestine Methamphetamine Laboratory. CLINICAL PEDIATRIC EMERGENCY MEDICINE 2006. [DOI: 10.1016/j.cpem.2006.07.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Cámpora P, Bermejo AM, Tabernero MJ, Fernández P. Use of gas chromatography/mass spectrometry with positive chemical ionization for the determination of opiates in human oral fluid. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:1288-92. [PMID: 16548052 DOI: 10.1002/rcm.2449] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
An analytical method for the simultaneous determination of codeine, morphine and 6-acetylmorphine (6AM) in human oral fluid was developed. The method involves liquid-liquid extraction in Toxitubes A, derivatization with 99:1 (v/v) N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA)/trimethylchlorosilane (TMCS), and gas chromatography/mass spectrometry with positive chemical ionization (GC/PCI-MS) determination. The detector response was linear over the concentration range 30-500 ng/mL with coefficients of correlation higher than 0.99. The precision was acceptable with coefficients of variation less than 7.5%. The limits of detection achieved were 0.7 ng/mL for codeine, 2.0 ng/mL for morphine, and 0.6 ng/mL for 6AM. The method proposed was applied to 80 oral fluid samples from opiates users, 98% of which were positive for the three analytes. Human oral fluid is a suitable biological fluid for the determination of opiates by GC/PCI-MS.
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Affiliation(s)
- Pamela Cámpora
- Institute of Legal Medicine, Forensic Toxicology Service, Faculty of Medicine, University of Santiago de Compostela, Spain
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Harvey BR, Shanafelt AB, Baburina I, Hui R, Vitone S, Iverson BL, Georgiou G. Engineering of recombinant antibody fragments to methamphetamine by anchored periplasmic expression. J Immunol Methods 2006; 308:43-52. [PMID: 16337958 DOI: 10.1016/j.jim.2005.09.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2005] [Revised: 09/13/2005] [Accepted: 09/15/2005] [Indexed: 11/18/2022]
Abstract
The detection of methamphetamine and other chemically related illicit drugs relies extensively on immunoassays. Here we report the cloning and affinity maturation of an anti-methamphetamine antibody which is being employed in the current commercial assays. An anti-methamphetamine scFv was cloned from hybridoma cells, expressed in bacteria and its affinity towards methamphetamine and N-ethylamphetamine (ethamphetamine) was determined by Surface Plasmon Resonance (SPR). The anti-methamphetamine scFv gene was subjected to random mutagenesis by error prone PCR and variants with improved affinity were isolated from the resulting library by a novel screening methodology termed Anchored Periplasmic Expression (APEx) [Harvey, B.R., Georgiou, G., Hayhurst, A., Jeong, K.J., Iverson, B.L., Rogers, G.K. (2004). Anchored periplasmic expression, a versatile technology for the isolation of high-affinity antibodies from Escherichia coli-expressed libraries. Proc. Natl. Acad. Sci. U. S. A. 101, 9193.]. The isolated clones exhibited improved affinity to these illicit drugs, yet maintained low cross-reactivity to over-the-counter drugs. In addition, all clones displayed improved expression characteristics in Escherichia coli. The affinity improved scFv antibodies are thus likely to be useful in methamphetamine class immunodiagnostics.
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Affiliation(s)
- Barrett R Harvey
- Institute for Cellular and Molecular Biology, University of Texas, Austin, TX, USA
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Concentrations of Unconjugated Morphine, Codeine and 6-Acetylmorphine in Urine Specimens from Suspected Drugged Drivers. J Forensic Sci 2002. [DOI: 10.1520/jfs15258j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Chang WT, Lin DL, Liu RH. Isotopic analogs as internal standards for quantitative analyses by GC/MS--evaluation of cross-contribution to ions designated for the analyte and the isotopic internal standard. Forensic Sci Int 2001; 121:174-82. [PMID: 11566421 DOI: 10.1016/s0379-0738(01)00396-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Isotopic analogs of the analytes are currently preferred internal standards (IS) for quantitative analyses of drugs and their metabolites in biological matrices by GC/MS procedures. Contributions of the analyte and the IS to the intensities of ions designated for the IS and the analyte, respectively--an undesirable phenomenon termed "cross-contribution"--greatly weakens the effectiveness of this approach. The cross-contribution phenomenon has been, in the past, evaluated by a "direct measurement" approach, in which intensities of interested ions were measured in two separate experiments using equal quantities of the analyte and the IS. Alternate procedures that may generate improved results are hereby studied. For the "improved direct measurement" approach, ion intensity data derived from the previously reported direct measurement procedure are first normalized before being used to calculate the extent of cross-contribution. An "internal standard" approach is also developed, in which a set amount of a third compound is incorporated into these two separate experiments, thus allowing corrections of ion intensity data that are imbedded with variations inherent to separate experiments. Finally, a "standard addition" approach, involving a series "addition" of "standards", generates multiple data points; thus, providing a mechanism to validate the resulting cross-contribution data. Secobarbital/(2)H(5)-secobarbital and secobarbital/(13)C(4)-secobarbital pairs are adapted as the exemplar systems for this study.
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Affiliation(s)
- W T Chang
- Graduate Program in Forensic Science, University of Alabama at Birmingham, Birmingham, AL 35294-2060, USA
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Broussard LA, Presley LC, Tanous M, Queen C. Improved Gas Chromatography–Mass Spectrometry Method for Simultaneous Identification and Quantification of Opiates in Urine as Propionyl and Oxime Derivatives. Clin Chem 2001. [DOI: 10.1093/clinchem/47.1.127] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Larry A Broussard
- Department of Clinical Laboratory Sciences, Louisiana State University Health Sciences Center, New Orleans, LA 70112-2262
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13C4-Secobarbital as the Internal Standard for the Quantitative Determination of Secobarbital—A Critical Evaluation. J Forensic Sci 2000. [DOI: 10.1520/jfs14743j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Application of chromatography and coupled chromatography-mass spectrometry for the investigation of pharmacokinetics and metabolism of propofol, clofelin, phencylidine, and tramadol (a review). Pharm Chem J 1999. [DOI: 10.1007/bf02508379] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Breindahl T, Andreasen K. Determination of 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid in urine using high-performance liquid chromatography and electrospray ionization mass spectrometry. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1999; 732:155-64. [PMID: 10517232 DOI: 10.1016/s0378-4347(99)00276-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
High-performance liquid chromatography with electrospray ionization mass spectrometry was used to determine 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in urine. After basic hydrolysis of conjugates, the compound was extracted using SPEC-PLUS-3ML-C18 solid-phase extraction columns. A deuterium labelled internal standard (d3-THC-COOH) was added prior to hydrolysis. Separation was performed on a reversed-phase Zorbax Eclipse XDB-C8 analytical column (150x3.0 mm I.D.) using a gradient program from 60 to 80% acetonitrile (4 mM formic acid) at a flow-rate of 0.5 ml/min. The compounds were detected by single ion monitoring of m/z 345 and m/z 348 for the protonated molecules [THC-COOH+H]+ and [d3-THC-COOH+H]+, respectively. The precision and accuracy were tested on spiked urine samples in the range 2.5-125 ng/ml. The mean recovery was 95% (n = 58), coefficients of variations were 2.2-4.3% and the limit of detection 2 ng/ml. Diagnostic qualifying ions of THC-COOH (m/z 327 and m/z 299) and d3-THC-COOH (m/z 330) were generated using up-front collision-induced dissociation. The relative ion intensities in clinical samples (n = 21) were within +/-20% deviation compared with standards. Using this tolerance and the presence of the ions m/z 327 and m/z 299 at the correct retention times as the acceptance criteria for identification of THC-COOH positive samples, the limit of detection was 15 ng/ml. The LC-MS method complies with the current recommendations on drugs of abuse testing, in which mass spectrometric detection is emphasized.
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Affiliation(s)
- T Breindahl
- Department of Clinical Chemistry, Hjørring/Brønderslev Hospital, Hjørring, Denmark.
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24
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Nowatzke W, Zeng J, Saunders A, Bohrer A, Koenig J, Turk J. Distinction among eight opiate drugs in urine by gas chromatography-mass spectrometry. J Pharm Biomed Anal 1999; 20:815-28. [PMID: 10701990 DOI: 10.1016/s0731-7085(99)00086-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Opiates are commonly abused substances, and forensic urine drug-testing for them requires gas chromatographic-mass spectrometric (GC-MS) confirmation. There are also medical reasons to test urine for opiates, and confirmation procedures other than GC-MS are often used for medical drug-testing. A thin-layer chromatographic (TLC) method distinguishes morphine, acetylmorphine, hydromorphone, oxymorphone, codeine, dihydrocodeine, hydrocodone, and oxycodone in clinical specimens. In certain clinical circumstances, GC-MS confirmation is requested for opiates identified by TLC, but, to our knowledge, no previous report examines all of the above opiates in a single GC-MS procedure. We find that they can be distinguished by GC-MS analyses of trimethylsilyl (TMS) ether derivatives, and identities of 6-keto opiates can be further confirmed by GC-MS analysis of methoxime (MO)-TMS derivatives. Inclusion of deuterium-labeled internal standards permits identification of the opiates in urine at concentrations below the TLC cutoff level of 600 ng/ml, and the GC-MS assay is linear over a concentration range that spans that level. This GC-MS procedure has proved useful as a third-stage identification step in a medical drug-testing sequence involving prior immunoassay and TLC.
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Affiliation(s)
- W Nowatzke
- Department of Pathology, Washington University School of Medicine, St. Louis, MO 63110, USA
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25
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Choi J, Kim C, Choi MJ. Comparison of capillary electrophoresis-based immunoassay with fluorescence polarization immunoassay for the immunodetermination of methamphetamine using various methamphetamine antibodies. Electrophoresis 1998; 19:2950-5. [PMID: 9870395 DOI: 10.1002/elps.1150191626] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
An accurate and simple immunoassay using capillary electrophoresis (CE) with laser-induced fluorescence (LIF) was performed for the detection of methamphetamine (MA) in urine. The CE-LIF was conducted with an untreated fused-silica column using antiserum and a tracer of fluorescein isothiocyanate (FITC)-labeled MA. This CE-LIF system was compared with fluorescence polarization immunoassay (FPIA) in a TDx analyzer in the photo-check mode using the same FITC-labeled tracer and the same antiserum. Various antibodies, not only those prepared by our own immunogens but also those from commercial sources, were screened and characterized in both assay systems with regard to sensitivity, precision, and cross-reactivity. Both systems satisfied analytical precision and gave similar cross-reactivity patterns. However, the CE-LIF-based immunoassay was approximately one order superior to FPIA in sensitivity, requiring less volume of sample, antiserum, and tracer for the assay. Considering that the FPIA system is well known to be a useful tool for screening antibodies and detecting drugs, the CE-LIF-based immunoassay system, which is seemingly more advantageous than the FPIA system, appears to have great power for the characterization of antibodies and for the detection of MA in urine.
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Affiliation(s)
- J Choi
- Bioanalysis and Biotransformation Research Center, Korea Institute of Science and Technology, Cheongryang, Seoul.
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26
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Moeller MR, Steinmeyer S, Kraemer T. Determination of drugs of abuse in blood. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 713:91-109. [PMID: 9700554 DOI: 10.1016/s0378-4347(97)00573-2] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The detection and quantitation of drugs of abuse in blood is of growing interest in forensic and clinical toxicology. With the development of highly sensitive chromatographic methods, such as high-performance liquid chromatography (HPLC) with sensitive detectors and gas chromatography-mass spectrometry (GC-MS), more and more substances can be determined in blood. This review includes methods for the determination of the most commonly occurring illicit drugs and their metabolites, which are important for the assessment of drug abuse: Methamphetamine, amphetamine, 3,4-methylenedioxymethamphetamine (MDMA), N-ethyl-3,4-methylenedioxyamphetamine (MDEA), 3,4-methylenedioxy-amphetamine (MDA), cannabinoids (delta-9-tetrahydrocannabinol, 11-hydroxy-delta-9-tetrahydrocannabinol, 11-nor-9-carboxy-delta-9-tetrahydrocannabinol), cocaine, benzoylecgonine, ecgonine methyl ester, cocaethylene and the opiates (heroin, 6-monoacetylmorphine, morphine, codeine and dihydrocodeine). A number of drugs/drug metabolites that are structurally close to these substances are included in the tables. Basic information about the biosample assayed, work-up, GC column or LC column and mobile phase, detection mode, reference data and validation data of each procedure is summarized in the tables. Examples of typical applications are presented.
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Affiliation(s)
- M R Moeller
- Institute of Legal Medicine, University of Saarland, Homburg (Saar), Germany
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27
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Segura J, Ventura R, Jurado C. Derivatization procedures for gas chromatographic-mass spectrometric determination of xenobiotics in biological samples, with special attention to drugs of abuse and doping agents. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 713:61-90. [PMID: 9700553 DOI: 10.1016/s0378-4347(98)00089-9] [Citation(s) in RCA: 162] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The development of low cost MS detectors in recent years has promoted an important increase in the applicability of GC-MS system to analyze for the presence of foreign substances in the human body. Drugs and toxic agents are in vivo metabolized in such a way that more polar compounds are usually formed. Derivatization of these metabolites is often an unavoidable requirement for gas chromatographic analysis. Application of derivatization methods in recent years has been relevant, especially for silylation, acylation, alkylation and the formation of cyclic or diastereomeric derivatives. Given the relevance of drug of abuse testing in modern toxicology, main derivatization procedures for opiates, cocaine, cannabis, amphetamines, benzodiazepines and LSD have been reviewed. Papers describing the analyses of drugs of abuse in matrixes other than blood, such as hair or sweat, have received special attention. Advances in derivatization for sports drug testing have been particularly relevant for anabolic steroids, diuretics and corticosteroids. Among the several methodologies applied, the formation of trimethylsilyl, perfluoroacyl or methylated derivatives have proved to be both versatile and extensively used. Further advances in derivatization for GC-MS applications in clinical and forensic toxicology will depend on the one hand on the degree of further use of GC-MS for routine applications and, on the other hand, on the alternative progress made for developments in LC-MS or CE-MS. Last but not least, the appearance of comprehensive libraries in which reference spectra for different derivatives of many drugs and their metabolites are collected will have an important impact on the expansion of derivatization in GC-MS for toxicological applications.
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Affiliation(s)
- J Segura
- Institut Municipal d'Investigació Mèdica IMIM, Drug Research Unit, Barcelona, Spain
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28
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Kraemer T, Maurer HH. Determination of amphetamine, methamphetamine and amphetamine-derived designer drugs or medicaments in blood and urine. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 713:163-87. [PMID: 9700558 DOI: 10.1016/s0378-4347(97)00515-x] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
This paper reviews procedures for the determination of amphetamine, methamphetamine and amphetamine-derived designer drugs or medicaments in blood and urine. Papers published from 1991 to early 1997 were taken into consideration. Gas chromatographic and liquid chromatographic procedures with different detectors (e.g., mass spectrometer or diode array) were considered as well as the seldom used thin-layer chromatography and capillary electrophoresis. Enantioselective procedures are also discussed. A chapter deals with amphetamine-derived medicaments, e.g. anoretics, antiparkinsonians or vasodilators, which are metabolized to amphetamine or methamphetamine. Differentiation of an intake of such medicaments from amphetamine or methamphetamine intake is discussed. Basic information about the biosample assayed, internal standard, work-up, GC column or LC column and mobile phase, detection mode, reference data and validation data of each procedure is summarized in Tables. Examples of typical applications are presented.
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Affiliation(s)
- T Kraemer
- Department of Toxicology, University of Saarland, Homburg (Saar), Germany
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29
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Badia R, de la Torre R, Corcione S, Segura J. Analytical approaches of European Union laboratories to drugs of abuse analysis. Clin Chem 1998. [DOI: 10.1093/clinchem/44.4.790] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
We report a survey on urine drug testing within a total of 269 laboratories of the European Union. Clinical laboratories predominated over forensic laboratories (59.5% vs 28.5%). Screening without identification/quantification was the common approach used by clinical laboratories, whereas screening with identification/quantification was the approach used by almost all forensic laboratories. Screening was primarily performed by immunoassay in both types of laboratories. Gas chromatography coupled to mass spectrometry was the main analytical method used for specific identification/quantification of drugs, but other methods (including immunoassays) were also used. Cutoff values applied varied by laboratory type, country, and method used. A high percentage of laboratories did not use or report cutoff values. Overall, countries of the European Union vary significantly in regards to drugs tested, analytical approach, and screening and identification cutoff values. It is recommended to clearly state the analytical method and the cutoff values used when reporting results for drugs of abuse testing.
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30
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Choi J, Kim C, Choi MJ. Immunological analysis of methamphetamine antibody and its use for the detection of methamphetamine by capillary electrophoresis with laser-induced fluorescence. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 705:277-82. [PMID: 9521564 DOI: 10.1016/s0378-4347(97)00527-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
An accurate, simple and rapid immunoassay is demonstrated for the detection of methamphetamine in urine by capillary electrophoresis (CE) with laser-induced fluorescence (LIF). An aminobutyl derivative of methamphetamine was conjugated with proteins, and used as an immunogen to produce antibodies for the assay. The methamphetamine derivative was also labeled with fluorescein isothiocyanate (FITC) to compete with free methamphetamine in the sample for the antibody binding site. Levels of free and antibody-bound FITC-labeled methamphetamine were monitored by performing CE-LIF using an untreated fused-silica column. This competitive immunoassay used antiserum instead of purified antibody or antibody fragment, yet was found to have good precision with a sensitivity of lower than 20 ng/ml. Various antibodies were also screened, and cross-reactivity of anti-MA antibody with methamphetamine analogues were also investigated. The results indicate that CE-LIF-based immunoassay is a powerful tool for the screening and characterization of antibody and may have possible applications in the detection of abused drugs in urine.
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Affiliation(s)
- J Choi
- Doping Control Center, Korea Institute of Science and Technology, Seoul, South Korea
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31
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Broussard LA, Presley LC, Pittman T, Clouette R, Wimbish GH. Simultaneous identification and quantitation of codeine, morphine, hydrocodone, and hydromorphone in urine as trimethylsilyl and oxime derivatives by gas chromatography–mass spectrometry. Clin Chem 1997. [DOI: 10.1093/clinchem/43.6.1029] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
Following enzymatic hydrolysis of urine, a gas chromatography–mass spectrometry method for the simultaneous determination of codeine, morphine, hydrocodone, and hydromorphone uses hydroxylamine to form oxime derivatives of the keto-opiates (i.e., hydrocodone, hydromorphone, oxycodone, and oxymorphone). These trimethylsilyl-derivatized forms no longer interfere with the detection and quantitation of codeine and morphine. Samples are extracted on solid-phase columns and quantitated by deuterated internal calibrations of each analyte with selected ion monitoring. Codeine, morphine, hydrocodone, and hydromorphone are completely separated, allowing simultaneous quantitation without interference and a chromatographic analysis time <9 min.
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Affiliation(s)
- Larry A Broussard
- Department of Medical Technology, LSU Medical Center, New Orleans, LA 70112-2262
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32
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Hemmersbach P, de la Torre R. Stimulants, narcotics and beta-blockers: 25 years of development in analytical techniques for doping control. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL APPLICATIONS 1996; 687:221-38. [PMID: 9001968 DOI: 10.1016/s0378-4347(96)00276-9] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
More than 25 years of developing doping control methods have led to comprehensive screening and confirmation procedures for stimulants, narcotics and beta-blockers. Much of this work has been initiated and/or improved by the late Prof. Dr. Manfred Donike. The methodological approach covered in this overview was applied to doping control procedures during the XXV Summer Olympics in Barcelona, Spain, in 1992 and the XVII Winter Olympics in Lillehammer, Norway, in 1994. Urine samples are screened through a combination of two analytical methods that are complementary: (a) gas chromatographic analysis of the parent compound and unconjugated metabolites, following single-step sample extraction and detection by a nitrogen-specific detector based on a retention index identification system and (b) gas chromatographic analysis including also conjugated drugs and metabolites after hydrolysis, solid-phase extraction, derivatisation and mass spectrometric detection. Confirmation and identification is always performed by gas chromatographic separation and full scan mass spectrometric detection. These methods facilitate the rapid screening and confirmation of more than 100 stimulants, narcotic analgesics and beta-blockers in urine for at least 24 h after the intake of a pharmaceutical dose. Application of the methods ensures high quality standards for the unequivocal identification of doping agents as well as a rapid turnaround time for sample analyses.
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Páez X, Rada P, Tucci S, Rodríguez N, Hernández L. Capillary electrophoresis-laser-induced fluorescence detection of amphetamine in the brain. J Chromatogr A 1996; 735:263-9. [PMID: 8767743 DOI: 10.1016/0021-9673(95)00820-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Prefrontal cortex microdialysis was done in rats that had received intraperitoneal amphetamine (AMPH). Samples were derivatized with 10(-4) M fluorescein isothiocyanate and incubated for 18 h. AMPH was separated by capillary electrophoresis (CE) and detected by laser-induced fluorescence detection (LIFD) from 30 to 150 min after injection. The limit of mass detection was 3 amol, which is three orders of magnitude lower than that in gas chromatography-mass spectrometry, and the limit of concentration detection was 3 x 10(-9) M. The results showed that CE-LIFD is a good method for detecting AMPH in brain dialysates of rats.
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Affiliation(s)
- X Páez
- Department of Physiology, School of Medicine, Universidad de los Andes, Mérida, Venezuela
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