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1.
BMC Med Educ ; 20(1): 445, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213443

RESUMO

BACKGROUND: Multiple-choice question (MCQ) tests are commonly used to evaluate medical students, but they do not assess self-confidence nor penalize lucky guess or harmful behaviors. Based on a scoring method according to the appropriateness of confidence in answers, the study aimed at assessing knowledge self-monitoring and efficiency, and the determinants of self-confidence. METHODS: A cross-sectional study of 842 s- and third-year medical students who were asked to state their level of confidence (A: very confident, B: moderately confident and C: not confident) during 12 tests (106,806 events). A bonus was applied if the level of confidence matched with the correctness of the answer, and a penalty was applied in the case of inappropriate confidence. RESULTS: Level A was selected more appropriately by the top 20% students whereas level C was selected more appropriately by the lower 20% students. Efficiency of higher-performing students was higher when correct (among correct answers, rate of A statement), but worse when incorrect compared to the bottom 20% students (among incorrect answers, rate of C statement). B and C statements were independently associated with female and male gender, respectively (OR for male vs female = 0.89 [0.82-0.96], p = 0.004, for level B and 1.15 [1.01-1.32], p = 0.047, for level C). CONCLUSION: While both addressing the gender confidence gap, knowledge self-monitoring might improve awareness of students' knowledge whereas efficiency might evaluate appropriate behavior in clinical practice. These results suggest differential feedback during training in higher versus lower-performing students, and potentially harmful behavior in decision-making during clinical practice in higher-performing students.


Assuntos
Estudantes de Medicina , Estudos Transversais , Retroalimentação , Feminino , Humanos , Conhecimento , Masculino
2.
Ther Drug Monit ; 36(1): 119-24, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24061447

RESUMO

BACKGROUND: A method for qualitative detection of 57 drugs and metabolites in umbilical cord tissue using liquid chromatography time-of-flight (TOF) mass spectrometry is described. METHODS: Results from 32 deidentified positive specimens analyzed by an outside laboratory using "screen with reflex to confirmation" testing were compared with TOF results. In addition, 57 umbilical cord tissue specimens paired with corresponding chart review data and 37 with meconium test results were analyzed by TOF. Urine drug test results from mother (n = 18) and neonate (n = 30) were included if available. Cutoff concentrations, recovery, and matrix effects were determined by analyzing fortified drug-free cord tissue and negative specimens. Cutoffs (in nanograms per gram) ranged from 1 to 10 for opioids and opioid antagonists, 5-10 for benzodiazepines and nonbenzodiazepine hypnotics, 20-40 for barbiturates, 8 for stimulants, and 4 for phencyclidine. Adequate sensitivity for the detection of cannabis exposure could not be realized with this method. CONCLUSIONS: Liquid chromatography time-of-flight mass spectrometry can provide accurate and sensitive detection of in utero drug exposure using umbilical cord tissue.


Assuntos
Cromatografia Líquida/métodos , Drogas Ilícitas/análise , Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Feminino , Humanos , Recém-Nascido , Mecônio/química , Gravidez , Sensibilidade e Especificidade , Cordão Umbilical/química
3.
Ther Drug Monit ; 33(1): 80-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21192312

RESUMO

Umbilical cord tissue was studied as a means of detecting prenatal exposure to nicotine. This was accomplished by comparing the presence and concentration of nicotine as well as nicotine metabolites in both umbilical cord tissue and paired meconium samples with maternal smoking histories obtained by self-report. Nicotine and metabolites (cotinine, 3-hydroxycotinine, nornicotine, and anabasine) were detected and quantitated using liquid chromatography-tandem mass spectroscopy. Between June and September 2009, 19 women with a tobacco exposure history (either first- or second-hand tobacco smoke exposure during pregnancy) were consented for the study. A questionnaire was completed to document nicotine exposure during each trimester of pregnancy. All infants were delivered at term (38 weeks or greater) and paired umbilical cord tissue (10-cm segment or greater) and meconium were obtained. Nicotine and 3-hydroxycotinine were most prominent in meconium, whereas cotinine and 3-hydroxycotinine were most prominent in the umbilical cord. Concentrations of all three analytes were generally higher in meconium. Nornicotine was detected only in meconium, at very low concentrations, and anabasine was not detected in either specimen. All analyte concentrations were lowest when the mother stated she quit smoking early in pregnancy or had only second-hand exposure, and detection was poor if exposure was limited to the first or second trimesters. Although different nicotine and metabolite patterns exist in meconium versus umbilical cord tissue, this work indicates that either specimen can be used to detect third-trimester fetal nicotine exposure.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Troca Materno-Fetal , Mecônio/química , Nicotina/análise , Cordão Umbilical/química , Anabasina/análise , Estimulantes do Sistema Nervoso Central/metabolismo , Cotinina/análogos & derivados , Cotinina/análise , Feminino , Humanos , Recém-Nascido , Exposição Materna , Nicotina/análogos & derivados , Nicotina/metabolismo , Gravidez , Fumar
4.
J Anal Toxicol ; 33(3): 148-54, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19371463

RESUMO

The results of meconium specimens and fortified samples screened for drugs of abuse by both enzyme multiplied immunoassay technique (EMIT((R) )II) and enzyme-linked immunosorbent assay (ELISA) methods were compared. The sample preparation for the ELISA screen was a simple buffer extraction versus a lengthy and more laborious sample preparation procedure for the EMIT II screen. The ELISA method was automated using a TECAN Genesis. The EMIT II analysis was automated with an Olympus AU400e. The opioid screen was calibrated with hydromorphone and the benzodiazepine screen was calibrated with clonazepam to maximize detection for these analytes. Previously validated gas chromatography-mass spectrometry (GC-MS), two-dimensional GC-MS, or liquid chromatography-tandem MS methods were used for confirmation. Results from the two techniques compared well. Agreement of the ELISA assay was greater than 90% when compared to EMIT II for all drug classes except barbiturates and benzodiazepines. ELISA appears to be more sensitive than EMIT II for the detection of amphetamines, methadone, propoxyphene, and cocaine. ELISA compared well to EMIT II for cannabinoids, opioids, and PCP. Specificity of the ELISA assay was slightly better for PCP and opioids. EMIT II appears to be more sensitive for the detection of barbiturates and benzodiazepines. The ELISA method reduced turnaround time by 50% compared to the EMIT II method.


Assuntos
Técnica de Imunoensaio Enzimático de Multiplicação , Ensaio de Imunoadsorção Enzimática/métodos , Drogas Ilícitas/análise , Mecônio/química , Detecção do Abuso de Substâncias/métodos , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Anfetaminas/análise , Analgésicos Opioides/análise , Barbitúricos/análise , Benzodiazepinas/análise , Canabinoides/análise , Cromatografia Líquida , Cocaína/análise , Dextropropoxifeno/análise , Reações Falso-Positivas , Feminino , Feto/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Recém-Nascido , Troca Materno-Fetal/fisiologia , Metadona/análise , Abuso de Fenciclidina/diagnóstico , Gravidez , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem
5.
J Anal Toxicol ; 33(3): 177-81, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19371469

RESUMO

Two versions of enzyme-linked immunosorbent assay (ELISA) kits designed for the detection of benzodiazepine drugs and metabolites (Immunalysis) were evaluated for use with meconium specimens. One was an older kit, and one was a new replacement kit developed for better detection of several commonly prescribed benzodiazepines and metabolites. The kits were evaluated by analyzing 68 patient specimens previously analyzed by liquid chromatography-tandem mass spectrometry and eight quality control samples. In addition to the recommended calibrator (oxazepam), clonazepam was evaluated as an alternate calibrator for the new kit. Detection and sensitivity for some analytes was improved using the new ELISA kit, but was reduced for others. The new kit using clonazepam as the calibrator provided the most sensitive assay for detection of the 11 benzodiazepines and metabolites reported here.


Assuntos
Benzodiazepinas/análise , Ensaio de Imunoadsorção Enzimática/métodos , Hipnóticos e Sedativos/análise , Mecônio/química , Detecção do Abuso de Substâncias/métodos , Calibragem , Clonazepam/análise , Feminino , Humanos , Recém-Nascido , Oxazepam/análise , Gravidez , Padrões de Referência , Reprodutibilidade dos Testes , Transtornos Relacionados ao Uso de Substâncias/diagnóstico
6.
J Anal Toxicol ; 32(7): 491-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18713517

RESUMO

A single method for confirmation and quantitation of a panel of commonly prescribed benzodiazepines and metabolites, alpha-hydroxyalprazolam, alpha-hydroxyethylflurazepam, alpha-hydroxytriazolam, alprazolam, desalkylflurazepam, diazepam, lorazepam, midazolam, nordiazepam, oxazepam, temazepam, clonazepam, and 7-aminoclonazepam, was developed for three specimen types, urine, serum/plasma, and meconium. Quantitation was by liquid chromatography tandem-mass spectrometry (LC-MS-MS) using a Waters Alliance-Quattro Micro system. The instrument was operated in multiple reaction monitoring mode with an electrospray ionization source in positive ionization mode. The method was evaluated for recovery, imprecision, linearity, analytical measurement range, specificity, and carryover. Average recovery and imprecision (within-run, between-run, and total % CV) were within +/- 15% of the target concentrations for urine (10 to 5000 ng/mL) and serum/plasma (10 to 2500 ng/mL) and within +/- 20% for meconium (10 to 5000 ng/g). In all, 205 patient specimens were analyzed, and the results compared to a previous in-house gas chromatography-MS method or LC-MS-MS results from an outside laboratory. Oxazepam glucuronide was evaluated as a hydrolysis control for the urine and meconium specimens.


Assuntos
Benzodiazepinas/análise , Benzodiazepinas/sangue , Benzodiazepinas/urina , Calibragem , Cromatografia Líquida de Alta Pressão , Humanos , Hidrólise , Indicadores e Reagentes , Espectrometria de Massas , Oxazepam/análogos & derivados , Oxazepam/análise , Oxazepam/sangue , Oxazepam/urina , Padrões de Referência , Reprodutibilidade dos Testes
7.
J Manag Care Spec Pharm ; 24(5): 423-429, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29694290

RESUMO

BACKGROUND: Clinical pharmacy services were initiated at 7 of 11 clinics within a primary care network (PCN), which was designated as a patient-centered medical home and was affiliated with a large academic medical center in October 2014. The goal of the service was to target patients with uncontrolled chronic conditions, specifically diabetes. Patients met with a clinical pharmacist through individual clinic and telephonic appointments, in addition to usual appointments with physicians as needed. While managing patients with diabetes, many clinicians assess a patient's hemoglobin A1c (A1c), along with blood pressure and cholesterol, as indicators of disease state control and cardiovascular risk. These 3 parameters were combined into a bundled response score (BRS) in order to assess whether the addition of the clinical pharmacy service had a positive effect on patient therapeutic goal attainment rates for these areas. OBJECTIVES: To assess the effect of pharmacist-led comprehensive medication management (CMM) on therapeutic goal attainment rates for glycemic, blood pressure, and dyslipidemia outcomes in PCN patients, which was represented by a BRS based on how many therapeutic goals were met. METHODS: This retrospective study was conducted using patients seen in clinics within the PCN between October 1, 2014, and October 31, 2015. Patients were included in the intervention group if they were actively managed by a PCN pharmacist and had a diagnosis of diabetes. A control group included patients without access to a PCN pharmacist and was matched to the intervention group by baseline A1c results. Based on current clinical practice guidelines, therapeutic goals for the BRS were set as A1c ≤ 8%, blood pressure ≤ 140/90 mmHg, and prescription of a moderate- to high-intensity statin for dyslipidemia. In addition to the primary outcome, the individual components of the BRS were assessed, as well as the average number of medications used between groups. RESULTS: There were 95 patients included in the intervention group, with 132 patients included in the usual care group. Patients in the intervention group had significantly higher rates of therapeutic goal attainment for the 3 endpoints (40% vs. 12%, P < 0.001). The intervention group had statistically significantly higher improvements in the individual areas of A1c, blood pressure, and statin goal attainment. There were no significant differences in the number of medications for diabetes or antihypertensive medications used between groups at the time of study termination. CONCLUSIONS: This study demonstrated that the addition of CMM services provided by clinical pharmacists in this PCN had a positive effect on therapeutic goal attainment rates for patients with diabetes. This finding suggests that the integration of clinical pharmacists into primary care clinics could have positive effects on the clinical outcomes of diabetic patients in glycemic control, blood pressure, and statin treatment, in accordance with current guidelines. DISCLOSURES: Support for this study was provided to Wilson by the National Center for Advancing Translational Sciences, National Institutes of Health, through grant number ULI TR001860. The content of this article is solely the responsibility of the authors and does not necessarily represent the views of the National Institutes of Health. The authors have nothing additional to disclose.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Conduta do Tratamento Medicamentoso/organização & administração , Assistência Centrada no Paciente/organização & administração , Farmacêuticos/organização & administração , Glicemia , Doença Crônica/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Feminino , Hemoglobinas Glicadas/análise , Objetivos , Humanos , Masculino , Pessoa de Meia-Idade , Assistência Centrada no Paciente/métodos , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos
8.
J Chromatogr B Analyt Technol Biomed Life Sci ; 858(1-2): 59-64, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17881300

RESUMO

Meconium has become the specimen of choice for determining fetal exposure to drugs of abuse, but its physical complexity can cause interferences from matrix effects. A new method to determine 9-carboxy-11-nor-Delta(9)-THC (9-THCA) and 11-hydroxy-Delta(9)-THC (11-OH-THC) using two-dimensional (2D) GC-MS was developed to reduce interferences and carryover. The method was validated using 70 spiked samples prepared in drug-free meconium and 46 residual patient specimens that were confirmed to contain cannabinoids. Ten patient specimens that failed to confirm due to interferences using the previous GC-MS method were analyzed using the new 2D method and 9-THCA was quantitated in all ten samples. The 2D GC-MS method improved chromatography which significantly reduced interferences and carryover when compared to the previous GC-MS method.


Assuntos
Canabinoides/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Mecônio/química , Detecção do Abuso de Substâncias/métodos , Dronabinol/análise , Humanos , Recém-Nascido , Reprodutibilidade dos Testes
9.
J Anal Toxicol ; 41(3): 196-204, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27881622

RESUMO

In this study, the stability of 21 cocaine, opioid and benzodiazepine analytes in spiked meconium was investigated at three storage temperatures: 4°C, room temperature (RT), and 37°C (body temperature). The drugs/metabolites included were hydrocodone, hydromorphone, codeine, morphine, 6-acetylmorphine (6-AM), oxycodone, oxymorphone, cocaine, cocaethylene, benzoylecgonine, m-hydroxybenzoylecgonine, diazepam, oxazepam, temazepam, nordiazepam, chlordiazepoxide, lorazepam, alprazolam, alpha-hydroxyalprazolam, clonazepam, 7-aminoclonazepam, midazolam, alpha-hydroxymidazolam and zolpidem. Drug testing was performed using mass spectrometry methods that were validated for clinical use. After 2 weeks of storage, a substantial loss was observed in the concentrations of 7-aminoclonazepam (48.4% at 4°C and 71.5% at RT), and chlordiazepoxide (59.5% at RT). A slight decrease was observed in the concentrations of alprazolam (20.9% at 4°C), clonazepam (24.5% at 4°C), chlordiazepoxide (23.5% at 4°C), midazolam (20.8% at 4°C), nordiazepam (22.8% at RT), and alpha-hydroxyalprazolam (20.7% at 4°C). At 37°C, the concentrations of chlordiazepoxide, 7-aminoclonazepam, lorazepam, oxazepam, nordiazepam and temazepam decreased by 81.4%, 86.8%, 56.5%, 59.9%, 45.4% and 31.7%, respectively, after 2 weeks. 6-AM was observed to be unstable regardless of storage temperatures. For morphine, a 33.3% increase at 4°C and a 23.4% increase at RT were observed after 2 weeks, respectively, possibly due to 6-AM degradation, while no changes ≥20% were observed at 37°C. All other analytes were stable up to 2 weeks at all three storage temperatures (concentration changes <20%). The stability of select drug analytes in authentic clinical meconium specimens was consistent with that observed in spiked meconium. In conclusion, some drugs in meconium may not be stable for long periods of time. Sample storage conditions are an important consideration in the context of detection windows and interpreting drug-testing results in meconium. To the best of our knowledge, this is the first stability study of cocaine, opioids and benzodiazepines in meconium concerning the effects of storage temperatures.


Assuntos
Analgésicos Opioides/análise , Benzodiazepinas/análise , Cocaína/análise , Estabilidade de Medicamentos , Mecônio/química , Manejo de Espécimes/métodos , Calibragem , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Recém-Nascido , Limite de Detecção
10.
Methods Mol Biol ; 1383: 59-68, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26660174

RESUMO

Buprenorphine (Suboxone, Zubsolv, Buprenex, Butrans, etc.) is an opioid drug that has been used to treat opioid dependence on an outpatient basis, and is also prescribed for managing moderate to severe pain. Pregnant women may be prescribed buprenorphine as part of a treatment plan for opioid addiction. This chapter quantitates buprenorphine and norbuprenorphine in meconium by liquid chromatography tandem mass spectrometry (LC-MS/MS).


Assuntos
Analgésicos Opioides/análise , Buprenorfina/análogos & derivados , Buprenorfina/análise , Cromatografia Líquida/métodos , Mecônio/química , Espectrometria de Massas em Tandem/métodos , Feminino , Humanos , Recém-Nascido , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Gravidez
11.
Methods Mol Biol ; 1383: 69-78, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26660175

RESUMO

Buprenorphine is an opioid drug that has been used to treat opioid dependence on an outpatient basis, and is also prescribed for managing moderate to severe pain. Some formulations of buprenorphine also contain naloxone to discourage misuse. The major metabolite of buprenorphine is norbuprenorphine. Both compounds are pharmacologically active and both are extensively metabolized to their glucuronide conjugates, which are also active metabolites. Direct quantitation of the glucuronide conjugates in conjunction with free buprenorphine, norbuprenorphine, and naloxone in urine can distinguish compliance with prescribed therapy from specimen adulteration intended to mimic compliance with prescribed buprenorphine. This chapter quantitates buprenorphine, norbuprenorphine, their glucuronide conjugates and naloxone directly in urine by liquid chromatography tandem mass spectrometry (LC-MS/MS). Urine is pretreated with formic acid and undergoes solid phase extraction (SPE) prior to analysis by LC-MS/MS.


Assuntos
Analgésicos Opioides/urina , Buprenorfina/análogos & derivados , Buprenorfina/urina , Naloxona/urina , Antagonistas de Entorpecentes/urina , Cromatografia Líquida/métodos , Monitoramento de Medicamentos/métodos , Humanos , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
12.
J Anal Toxicol ; 40(1): 37-42, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26342055

RESUMO

Some amphetamine (AMP) and ecstacy (MDMA) urine immunoassay (IA) kits are prone to false-positive results due to poor specificity of the antibody. We employed two techniques, high-resolution mass spectrometry (HRMS) and an in silico structure search, to identify compounds likely to cause false-positive results. Hundred false-positive IA specimens for AMP and/or MDMA were analyzed by an Agilent 6230 time-of-flight (TOF) mass spectrometer. Separately, SciFinder (Chemical Abstracts) was used as an in silico structure search to generate a library of compounds that are known to cross-react with AMP/MDMA IAs. Chemical formulas and exact masses of 145 structures were then compared against masses identified by TOF. Compounds known to have cross-reactivity with the IAs were identified in the structure-based search. The chemical formulas and exact masses of 145 structures (of 20 chemical formulas) were compared against masses identified by TOF. Urine analysis by HRMS correlates accurate mass with chemical formulae, but provides little information regarding compound structure. Structural data of targeted antigens can be utilized to correlate HRMS-derived chemical formulas with structural analogs.


Assuntos
Anfetamina/química , Anfetamina/urina , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , N-Metil-3,4-Metilenodioxianfetamina/química , N-Metil-3,4-Metilenodioxianfetamina/urina , Reações Cruzadas , Reações Falso-Positivas , Humanos , Imunoensaio , Kit de Reagentes para Diagnóstico/normas
13.
J Anal Toxicol ; 39(2): 89-95, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25505058

RESUMO

Urine and plasma specimens fortified with 82 drugs and metabolites were prepared and analyzed by liquid chromatography quadrupole time-of-flight mass spectrometry (QTOF) instrumentation from three different vendors using the instrument manufacturers' methods and workflows for drug screening. No prior knowledge about the compounds included or their concentrations were provided. Samples were prepared and sent for analysis on a TripleTOF(®) 5600 system, a 6530 QTOF and a Xevo(®) G2-S QTof. All three platforms performed well with >90% of compounds detected in one set of spiked plasma samples, and 79-88% for a second set of spiked plasma and two sets of spiked urine samples.


Assuntos
Cromatografia Líquida/métodos , Preparações Farmacêuticas/análise , Espectrometria de Massas em Tandem/métodos , Humanos
14.
Am J Clin Pathol ; 143(2): 234-40, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25596249

RESUMO

OBJECTIVES: The major objective of this research was to propose a simplified approach for the evaluation of medication adherence in chronic pain management patients, using liquid chromatography time-of-flight (TOF) mass spectrometry, performed in parallel with select homogeneous enzyme immunoassays (HEIAs). We called it a "hybrid" approach to urine drug testing. METHODS: The hybrid approach was defined based on anticipated positivity rates, availability of commercial reagents for HEIAs, and assay performance, particularly analytical sensitivity and specificity for drug(s) of interest. Subsequent to implementation of the hybrid approach, time to result was compared with that observed with other urine drug testing approaches. RESULTS: Opioids, benzodiazepines, zolpidem, amphetamine-like stimulants, and methylphenidate metabolite were detected by TOF mass spectrometry to maximize specificity and sensitivity of these 37 drug analytes. Barbiturates, cannabinoid metabolite, carisoprodol, cocaine metabolite, ethyl glucuronide, methadone, phencyclidine, propoxyphene, and tramadol were detected by HEIAs that performed adequately and/or for which positivity rates were very low. Time to result was significantly reduced compared with the traditional approach. CONCLUSIONS: The hybrid approach to urine drug testing provides a simplified and analytically specific testing process that minimizes the need for secondary confirmation.


Assuntos
Analgésicos/urina , Dor Crônica/tratamento farmacológico , Adesão à Medicação , Detecção do Abuso de Substâncias/métodos , Analgésicos/uso terapêutico , Humanos , Imunoensaio , Estudos Retrospectivos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
16.
J Chromatogr A ; 1030(1-2): 255-62, 2004 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-15043277

RESUMO

Six commercially available analytical (4.1 or 4.6 mm i.d.) columns were evaluated under temperature-programmed high-temperature liquid chromatography (HTLC) conditions to access their stability and performance at extreme temperatures. Seven components consisting of acidic, basic and neutral compounds were analyzed under temperature-programmed conditions and solvent gradient conditions using three different mobile phase compositions (acidic, basic and neutral). Each column was checked with a two-component test mix at various stages of the evaluation to look for signs of stationary phase collapse. Three zirconia based stationary phases studied exhibited column bleed under temperature-programmed conditions. The other three columns, a polydentate silica column, a polystyrene-divinylbenzene (PS-DVB) polymeric column, and a graphitic carbon column performed well with no evidence of stationary phase degradation. The R.S.D. for the retention times and efficiencies were less than 10% for most conditions, and not more than 15% during the course of the evaluation for each column. The polydentate silica stationary phase was temperature programmed to 100 degrees C, the PS-DVB stationary phase was temperature programmed up to 150 degrees C, and the graphitic carbon column was used with temperature programming up to 200 degrees C. Comparable peak capacities and similar retention behaviors were observed under solvent gradient and temperature-programmed conditions. Temperature programming with dynamic mobile phase preheating can replace solvent gradient analysis without a loss of peak capacity when used with 4.1 or 4.6 mm columns.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Equipamentos e Provisões/normas , Temperatura Alta
17.
J Pain Palliat Care Pharmacother ; 27(4): 322-39, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24147959

RESUMO

This comprehensive review of analytical methods used for urine drug testing for the support of pain management describes the methods, their strengths and limitations, and types of analyses used in clinical laboratories today. Specific applications to analysis of opioid levels are addressed. Qualitative versus quantitative testing, immunoassays, chromatographic methods, and spectrometry are discussed. The importance of proper urine sample collection and processing is addressed. Analytical explanations for unexpected results are described. This article describes the scientific basis for urine drug testing providing information which will allow clinicians to differentiate between valid and questionable claims for urine drug testing to monitor medication adherence among chronic pain patients.


Assuntos
Analgésicos Opioides/uso terapêutico , Dor Crônica/tratamento farmacológico , Adesão à Medicação , Detecção do Abuso de Substâncias/métodos , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/urina , Cromatografia/métodos , Humanos , Imunoensaio/métodos , Análise Espectral/métodos
18.
J Anal Toxicol ; 36(7): 472-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22833647

RESUMO

This paper reports an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) method to quantitate 21 benzodiazepines, zolpidem and zopiclone in serum and plasma. After liquid-liquid extraction, an Acquity UPLC with a TQ Detector and BEH C18 column was used (Waters, Milford, MA). The injection-to-injection run time was 7.5 min. Forty-eight authentic serum and plasma patient specimens were analyzed and results compared to those obtained using a previously published method. Average r(2) values for linearity (1 to 1,000 ng/mL over five days) were all above 0.995, except α-hydroxytriazolam (0.993). Intra-day and inter-day relative standard deviation values were within ± 15% and the percent deviation from the expected concentrations were within ± 11%. Recovery ranged from 62 to 89%. Matrix effects ranged from -28% to +6%. The limits of detection were 1 ng/mL, except for lorazepam, nordiazepam, oxazepam and temazepam (5 ng/mL). Ion ratios were ± 15% for all analytes. For authentic patient specimens (n = 48, 76 positive results), there was excellent correlation between the UPLC-MS-MS results and the previous method. The best least-squares fit had an equation of y = 1.0708x + 1.6521, r(2) = 0.9822. This UPLC-MS-MS method is suitable for the quantification of benzodiazepines and hypnotics in serum and plasma, and offers fast, reliable and sensitive results.


Assuntos
Compostos Azabicíclicos/sangue , Benzodiazepinas/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Piperazinas/sangue , Piridinas/sangue , Espectrometria de Massas em Tandem/métodos , Humanos , Extração Líquido-Líquido/métodos , Lorazepam/análise , Nordazepam/análise , Oxazepam/análise , Plasma/química , Soro/química , Manejo de Espécimes/métodos , Temazepam/análise , Triazolam/análogos & derivados , Triazolam/análise , Zolpidem
19.
J Anal Toxicol ; 36(2): 81-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22337776

RESUMO

Patterns of buprenorphine and metabolites were examined in 1946 positive urine samples analyzed by liquid chromatography-tandem mass spectrometry for free (unconjugated) buprenorphine and norbuprenorphine (quantitative, 2 to 1000 ng/mL) and buprenorphine-glucuronide (B3G) and norbuprenorphine-glucuronide (N3G) (semi-quantitative, 5 to 1000 ng/mL). Two distribution patterns predominated with 49.1% positive for norbuprenorphine, B3G, and N3G and 41.6% positive for buprenorphine, norbuprenorphine, B3G, and N3G. Buprenorphine, positive in 45.5% of samples, was mostly < 5 ng/mL (median 6.1 ng/mL), but 9.8% were > 1000 ng/mL. Norbuprenorphine, B3G, and N3G had semi-Gaussian distributions with medians of 64.7, 108, and 432 ng/mL, respectively. With buprenorphine < 100 ng/mL (767 samples) or ≥ 100 ng/mL (19 quantifiable samples), the respective median metabolic ratios (free norbuprenorphine/free buprenorphine) were 25.0 and 0.15. In 12 retested "> 1000 ng/mL" buprenorphine samples, free buprenorphine was 4160 to 39,400 ng/mL and free naloxone 2140 to 9560 ng/mL. In 87 subsequent samples with buprenorphine < 20 ng/mL, naloxone concentrations were < 50 ng/mL. Concentrations of buprenorphine > 100 ng/mL (particularly with low metabolite concentrations) are suspect of urine adulteration with medication (4% in the database) that can be checked in most cases by concurrent analysis for naloxone.


Assuntos
Buprenorfina/análogos & derivados , Buprenorfina/urina , Cromatografia Líquida/métodos , Glucuronídeos/urina , Espectrometria de Massas em Tandem/métodos , Humanos , Naloxona/urina , Manejo de Espécimes/métodos
20.
J Anal Toxicol ; 36(7): 477-86, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22802572

RESUMO

Sixty-seven drugs and metabolites were detected in serum or plasma using a fast (7.5 min) liquid chromatography time-of-flight mass spectrometry (LC-TOF-MS) method. This method was developed as a blood drug screen, with emphasis on the detection of common drugs of abuse and drugs used to manage chronic pain. Qualitative drug detection may identify a drug exposure, assure patient adherence with prescribed therapy and document abstinence from non-prescribed medications. Compound identification is based on chromatographic retention time, mass, isotope spacing and isotope abundance. Data analysis software (Agilent) generates a compound score based on how well these observed criteria matched theoretical and empirical values. The method was validated using fortified samples and 299 residual patient specimens (920 positive results). All results were confirmed by gas chromatography-MS or LC-tandem MS. The accuracy of positive results (samples meeting all qualitative criteria for retention time, mass and compound score) was >90% for drugs and/or metabolites, except for two benzodiazepines. There were 35 false positive results (seven compounds, 3.8%) that could be distinguished by retention time and/or absence of metabolites. The most frequent was 6-acetylmorphine in the absence of morphine. The LC-TOF-MS targeted screening method presented represents a sensitive and specific technology for drug screening of serum or plasma.


Assuntos
Benzodiazepinas/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Derivados da Morfina/sangue , Preparações Farmacêuticas/sangue , Detecção do Abuso de Substâncias/métodos , Humanos , Plasma/química , Reprodutibilidade dos Testes , Soro/química , Software , Manejo de Espécimes/métodos , Estatística como Assunto , Espectrometria de Massas em Tandem/métodos
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