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1.
Forensic Toxicol ; 42(2): 232-241, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38240998

RESUMO

PURPOSE: Intravenous narcotic agents, such as etomidate and metomidate, has been widely spread and abused in the world, including in Korea and China; thus, it is important to establish validated and sensitive analytical method for these compounds. Human hair as a biological sample has various advantages, including a wide detection window of drugs, compared to other typical samples, such as urine and blood in investigation. The purpose of this communication is to develop a reliable and useful method for the simultaneous detection and quantification of etomidate and metomidate in human hair samples by ultraperformance liquid chromatography combined with triple quadrupole mass spectrometry (UPLC-MS/MS), and to apply it for authentic samples in abuse cases. METHODS: The hair samples were washed with a detergent solution, followed by with water and acetone. After drying, they were cut into approximately 2 mm sections and then ground to powder by a low-temperature grinder. The 20 mg of hair powder plus internal standard in 1 mL of methanol was vortexed and then centrifuged to obtain the supernatant layer, followed by subjecting to analysis. RESULTS: The coefficient of determination (r2) values of the calibration curves of etomidate and metomidate in the hair samples were both more than 0.99 in the range of 1-500 ng/mg and 1-500 pg/mg, respectively. The limits of detection and lower limits of quantification were 0.5 and 1 pg/mg, respectively, for the both target compounds. Other tested validation data were all satisfactory. Etomidate and metomidate could be detected in the all hair samples and cigarette oil, which were seized by the police. The concentrations of etomidate and metomidate obtained from 10 samples from suspects were 5.48-45.7 ng/mg and 3.60-377 pg/mg, respectively. The concentrations of etomidate and metomidate in the cigarette oil were 95.8 µg/mg and 2.8 µg/mg, respectively. CONCLUSIONS: In this study, a simple and reliable analytical method for etomidate and metomidate in the human hair has been established. To the best of our knowledge, this is the first report to establish a method for the simultaneous detection and quantification of etomidate and metomidate in the human hair, and to apply it to authentic samples seized in authentic cases.


Assuntos
Etomidato , Cabelo , Detecção do Abuso de Substâncias , Humanos , Etomidato/análogos & derivados , Etomidato/análise , Cabelo/química , Detecção do Abuso de Substâncias/métodos , Cromatografia Líquida/métodos , Toxicologia Forense/métodos , Estimulantes do Sistema Nervoso Central/análise , Espectrometria de Massas em Tandem/métodos , Limite de Detecção , Espectrometria de Massas/métodos , Cromatografia Líquida de Alta Pressão/métodos , Metilfenidato/análogos & derivados , Metilfenidato/análise , Masculino , Espectrometria de Massa com Cromatografia Líquida
2.
J Forensic Sci ; 67(2): 669-675, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34985135

RESUMO

Oral fluid is an alternative matrix that has proven to be useful for the detection of drugs. Oral fluid is easy to collect, noninvasive, and may indicate recent drug use. There are limited methods available that analyze cognitive stimulants in oral fluid. Cognitive stimulants are used to treat attention-deficit/hyperactivity disorder (ADHD), a neurological disorder that emerges from lack of dopamine in the brain. To combat this disorder, medications inhibit dopamine and norepinephrine reuptake by blocking transporters in the brain. Though commonly diagnosed in children, ADHD may extend beyond adolescence and abuse of medications in college students is not uncommon. The goal of this study was to develop and validate a quantitative method for methylphenidate, ethylphenidate, lisdexamfetamine, and amphetamine in oral fluid using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Analytes were isolated by solid-phase extraction and analyzed on an Agilent 1290 Infinity II Liquid Chromatograph coupled to an Agilent 6470 Triple Quadrupole Mass Spectrometer. The linear range was 0.5-100 ng/ml (except lisdexamfetamine at 5-500 ng/ml). Bias and between-run precision were acceptable (±11.0% bias and ±12.2%CV). No interferences or carryover were observed and dilution integrity was sustained. This validated method was applied to four authentic oral fluid samples collected with Quantisal® devices from college students. Lisdexamfetamine was quantified in one sample at 5.8 ng/ml while amphetamine was quantified in all four samples at 6.0-78.8 ng/ml. This is the first known quantitative method in oral fluid that includes these analytes using LC-MS/MS and may give rise to interpretive value in a forensic toxicology setting.


Assuntos
Dimesilato de Lisdexanfetamina , Metilfenidato , Adolescente , Anfetamina/análise , Criança , Cromatografia Líquida , Humanos , Dimesilato de Lisdexanfetamina/análise , Metilfenidato/análogos & derivados , Metilfenidato/análise , Espectrometria de Massas em Tandem
3.
Artigo em Inglês | MEDLINE | ID: mdl-34951564

RESUMO

Methylphenidate (MPH) is an important emerging pollutant found in effluents and wastewater. Thus, we aimed to develop and validate a method for detection and quantitation of MPH residues in sewage through high performance liquid chromatography coupled with photodiode array detector (LC-PDA). Here we describe a selective, accurate, precise, and valid method for determination of MPH in sewage with a total running time of 10 min, with limits of detection and quantification of 0.27 and 0.92 µg/mL, respectively. MPH retention peak was observed at 5 min. The method was applied to MPH analysis in a sewage sample pretreated with solid phase extraction, obtaining a result of 2.8 µg/L of MPH. Thus, the developed method can be considered feasible to be applied to MPH residual contamination analysis in sewage using a widely available apparatus.


Assuntos
Metilfenidato , Poluentes Químicos da Água , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Metilfenidato/análise , Metilfenidato/química , Esgotos/química , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/análise
4.
Molecules ; 26(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34641342

RESUMO

Methylphenidate is a powerful central nervous system stimulant with a high potential for abuse in horse racing. The detection of methylphenidate use is of interest to horse racing authorities for both prior to and during competition. The use of hair as an alternative sampling matrix for equine anti-doping has increased as the number of detectable compounds has expanded. Our laboratory developed a liquid chromatography-high-resolution mass spectrometry method to detect the presence of methylphenidate in submitted samples. Briefly, hair was decontaminated, cut, and pulverized prior to liquid-liquid extraction in basic conditions before introduction to the LC-MS system. Instrumental analysis was conducted using a Thermo Q Exactive mass spectrometer using parallel reaction monitoring using a stepped collision energy to obtain sufficient product ions for qualitative identification. The method was validated and limits of quantitation, linearity, matrix effects, recovery, accuracy, and precision were determined. The method has been applied to confirm the presence of methylphenidate in official samples submitted by racing authorities.


Assuntos
Cabelo/química , Extração Líquido-Líquido/métodos , Metilfenidato/análise , Animais , Cromatografia Líquida , Cavalos , Espectrometria de Massas , Detecção do Abuso de Substâncias/veterinária
5.
Int J Legal Med ; 134(1): 229-241, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31735981

RESUMO

This study centres on the prevalence of new psychoactive substances (NPS) stimulant use, and its relevance as a cause of death amongst individuals between the ages of 12 and 35 in the greater Cologne area. An automated solid-phase extraction-liquid chromatography-tandem mass spectrometry method was developed for the determination of 97 stimulants in urine (including conventional stimulants, e.g. amphetamine and MDMA), of which 68 analytes were fully validated for quantification. Samples of urine or kidney tissue (in cases where urine was unavailable) of 268 deceased were collected, during autopsy, between January 2011 and May 2017 and analyzed. Blood (if available) was also investigated in cases where urine/kidney samples were tested positive for NPS. An intake of stimulants (including NPS stimulants) was proven in 50 cases. In 33 cases, only conventional stimulants were detected. A total of 17 cases were tested positive for NPS. Of the 17 NPS-positive cases, 13 were also tested positive for other conventional drugs of abuse (mostly amphetamine and MDMA). In six NPS-positive cases, at least three different NPS were proven to be ingested. Due to the determined blood concentrations, NPS was assigned as the leading cause of death, or of toxicological relevance, in the cause of death in only 5 cases. In two of the cases, NPS was judged to be a component of a multidrug poisoning, but of minor relevance.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Detecção do Abuso de Substâncias/métodos , Adolescente , Adulto , Anfetaminas/análise , Autopsia , Causas de Morte , Criança , Cromatografia Líquida , Feminino , Alemanha/epidemiologia , Humanos , Ketamina/análise , Masculino , Metilfenidato/análise , Prevalência , Psicotrópicos/classificação , Extração em Fase Sólida , Espectrometria de Massas em Tandem
6.
J Anal Toxicol ; 43(8): 666-672, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31424072

RESUMO

The (±)-threo-4-fluoromethylphenidate (4F-MPH) is a fluorinated analog of the prescription central nervous system stimulant medication, methylphenidate. This novel psychoactive substance was first detected in drug paraphernalia at the Miami-Dade County Medical Examiner Department Toxicology Laboratory in 2016 but was not detected in a biological specimen until 2018. Limited literature is available on 4F-MPH, with predominate literature being published out of Europe, and no known toxicities reported in the USA. Post-mortem specimens were screened using both gas chromatography mass spectrometry and liquid chromatography ion trap mass spectrometry (LC-Ion Trap-MSn). In addition, a validated method for the quantification of 4F-MPH was developed using liquid chromatography-tandem mass spectrometry (LC-MS-MS), with a linear range of 0.01-0.500 mg/L and acceptable validation criteria including precision, bias, carry-over, linearity and endogenous/exogenous interferences. In addition to the detection of 4F-MPH, 3-methoxy-PCP, amphetamine, methamphetamine, 6-monoacetylmorphine, morphine, codeine and tetrahydrocannabinol were also identified in the decedent. A single source of blood was collected (femoral vein) and quantified in all blood tubes used for collection, with concentrations varying from 0.012 to 0.05 mg/L. Additional specimens available for screening included gastric contents and urine. An additional peak having the same targeted ions and transitions as 4F-MPH was identified in both the LC-Ion Trap-MSn screening procedure and the LC-MS-MS quantitative procedure. This peak suggests the presence of a structural isomer, possibly (±)-erythro-4-fluoromethylphenidate, which cannot be confirmed due to there being no available certified reference material. This case report presents the first time that 4F-MPH was detected in a decedent, as well as the first time 4F-MPH has been listed in the official cause of death of a decedent in Florida.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Estimulantes do Sistema Nervoso Central/toxicidade , Toxicologia Forense , Metilfenidato/análogos & derivados , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Adulto , Cromatografia Líquida de Alta Pressão , Evolução Fatal , Humanos , Masculino , Metilfenidato/análise , Metilfenidato/toxicidade , Reprodutibilidade dos Testes , Manejo de Espécimes , Espectrometria de Massas em Tandem
7.
Chemosphere ; 233: 771-785, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31200137

RESUMO

Pharmaceuticals which originally were designed to treat people with neurological and psychiatric conditions, e.g. Alzheimer's disease or attention deficit hyperactivity disorder (ADHD), are nowadays often misused by students as a 'brain doping' substances. These substances are known as nootropic drugs, smart drugs or cognitive enhancers, as they increase memory, attention and concentration of healthy individuals. Since they are easily available illicitly, their consumption is observed to be growing. Currently, these pharmaceuticals started gaining researchers' attention, especially since they have been recently detected in wastewater, surface water and even drinking water. This review summarises the current state of knowledge on nootropic drugs in terms of their population use trends and ethics, occurrence in the environment and detection techniques, toxicity and removal methods, in example of methylphenidate, modafinil and piracetam - three most popular nootropics. It points out that the main sources of knowledge on cognitive enhancers illicit use are often inconsistent questionnaires, which are not supported by wastewater analysis to become more veracious. Simultaneously, the studies concerning toxicity and removal methods of nootropic drugs are still limited and in many cases environmentally irrelevant. Although the prescription rules has been subjected to more strict control in developed countries, regulatory frameworks with regard to their ecosystem occurrence are still lacking and should be introduced. Moreover, the use of environmentally relevant concentrations in toxicity studies should be a standard, leading to proper ecotoxicity risk assessment. Based on this review, it is recommended to routinely monitor nootropics and their metabolites in waste- and surface waters.


Assuntos
Poluentes Ambientais/análise , Nootrópicos/análise , Transtorno do Deficit de Atenção com Hiperatividade , Encéfalo , Poluentes Ambientais/toxicidade , Humanos , Memória , Metilfenidato/análise , Metilfenidato/toxicidade , Modafinila/análise , Modafinila/toxicidade , Nootrópicos/toxicidade , Piracetam/análise , Piracetam/toxicidade , Águas Residuárias
8.
Forensic Sci Int ; 294: 183-188, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30530155

RESUMO

Methylphenidate (MPH) is one of the most commonly prescribed stimulants for attention deficit hyperactivity disorder and its abuse is on the rise with its growing availability. Some analytical methods have been reported for the detection of MPH in hair. However, the concentration range of MPH as well as its metabolite, ritalinic acid (RA) in the hair of MPH abuse cases has not been reported. In this study, a sensitive and reliable liquid chromatography-tandem mass spectrometry method was developed and validated for the simultaneous determination of MPH and RA in hair. Sample preparation was carried out by a simple methanol extraction using 10mg of hair. Limits of detection for MPH and RA in hair were 0.5pg/mg and 1pg/mg, respectively, and the limits of quantification (LOQs) were 1pg/mg for both the analytes. Validation results showed good linearity in the range of 1-100pg/mg with acceptable precision and accuracy. The developed method was applied to real hair samples obtained from ten drug users who obtained MPH illegally without a prescription. MPH concentrations in the hair samples ranged from 1.0pg/mg to 265.0pg/mg, and RA was present at concentrations

Assuntos
Estimulantes do Sistema Nervoso Central/análise , Cabelo/química , Metilfenidato/análogos & derivados , Metilfenidato/análise , Detecção do Abuso de Substâncias , Cromatografia Líquida , Humanos , Limite de Detecção , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Espectrometria de Massas em Tandem
9.
Artigo em Inglês | MEDLINE | ID: mdl-29935479

RESUMO

Methylphenidate (MPH), which is metabolized into ritalinic acid (RA), is an amphetamine derivative largely used in the treatment of attention-deficit hyperactivity disorder, a neurological condition commonly diagnosed in early childhood. Ensuring that patients comply with clinical treatment is crucial and compliance is generally monitored in blood or urine specimens which, especially in the case of children, can be challenging to obtain on a repetitive basis. Here we report validation of a specific, non-invasive, and rapid dilute-and-shoot analytical method for the detection and quantitation of MPH and RA in oral fluid (OF). The method is based on liquid chromatography coupled to triple quadrupole MS with electrospray ionization utilizing dynamic MRM mode. Subject OF specimens were collected using a Quantisal™ device, processed, and diluted for analysis with seven-point quadratic calibration curves (weighting of 1/x) using MPH-d9 and (±)-threo-RA-d10 as internal standards. QC samples and diluted specimens showed intra- and inter-day bias and imprecision values no greater than ±12%. The LOD and LOQ for MPH were 0.1 and 0.5 ng/mL, respectively, and 0.2 ng/mL and 0.5 ng/mL for RA, respectively, indicating the validity of the method for identification and confirmation at low concentrations. Selectivity was specific for the analytes of interest and matrix effects were minimized through the use of internal standard based quantitation.


Assuntos
Cromatografia Líquida/métodos , Metilfenidato/análogos & derivados , Metilfenidato/análise , Saliva/química , Espectrometria de Massas em Tandem/métodos , Transtorno do Deficit de Atenção com Hiperatividade , Pré-Escolar , Estabilidade de Medicamentos , Humanos , Limite de Detecção , Metilfenidato/química , Reprodutibilidade dos Testes
10.
N Biotechnol ; 43: 30-36, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28855122

RESUMO

The consumption of nootropic drugs has increased tremendously in the last decade, though the studies on their environmental fate are still scarce. Nootropics are bioactive compounds designed to alter human's physiology therefore the adverse effects towards wildlife can be expected. In order to understand their environmental impact, the knowledge on their transformation pathways is necessary. Methylphenidate belongs to the most prescribed neuro-enhancers and is among the most favored smart drugs used in non-medical situations. It is metabolized in human liver and excreted as ritalinic acid. Here, we showed for the first time that ritalinic acid can be biodegraded and used as a sole carbon and nitrogen source by various microbial strains originating from different environmental samples. Five axenic strains were isolated and identified as: Arthrobacter sp. strain MW1, MW2 and MW3, Phycicoccus sp. strain MW4 and Nocardioides sp. strain MW5. Our research provides the first insight into the metabolism of ritalinic acid and suggests that it may differ depending on the strain and growth conditions, especially on availability of nitrogen. The isolates obtained in this study can serve as model organisms in further studies on the catabolism of ritalinic acid and methylphenidate but potentially also other compounds with similar structures. Our findings have important implication for the sewage epidemiology. We demonstrated that ritalinic acid is subject to quick and efficient biodegradation thus its use as a stable biomarker should be reconsidered.


Assuntos
Actinomycetales/isolamento & purificação , Arthrobacter/isolamento & purificação , Metilfenidato/análogos & derivados , Metilfenidato/metabolismo , Actinomycetales/crescimento & desenvolvimento , Arthrobacter/crescimento & desenvolvimento , Biodegradação Ambiental , Cromatografia Líquida de Alta Pressão , Humanos , Metilfenidato/análise , Estrutura Molecular
11.
N Biotechnol ; 43: 44-52, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28855123

RESUMO

Methylphenidate is widely used as a medication for the treatment of attention deficit hyperactivity disorder (ADHD) in children. Less than 1% of methylphenidate is excreted unchanged in urine, while 80% of an oral dose is excreted as ritalinic acid (which is reportedly poorly degradable). This study aims to investigate the biotransformation of ritalinic acid by free and immobilized enzymes. The influence of various laccase mediators on biotransformation efficiency has been tested. Formation of the main transformation products has been monitored and their potential structures suggested. The effective transformation of ritalinic acid was observed only in the presence of 2,2,6,6-tetramethylpiperidine 1-oxyl mediator (TEMPO). The most effective enzyme was the laccase of T. versicolor 159. The main transformation product was an N-methyl derivative of ritalinic acid. Ritalinic acid was also reduced to aldehyde and alcohol, and a broad spectrum of intermediate complexes with oxoammonium ion of TEMPO were detected. This is the first time the biotransformation of ritalinic acid has been investigated in detail.


Assuntos
Óxidos N-Cíclicos/metabolismo , Lacase/metabolismo , Metilfenidato/análogos & derivados , Álcoois/química , Álcoois/metabolismo , Aldeídos/química , Aldeídos/metabolismo , Biotransformação , Óxidos N-Cíclicos/química , Enzimas Imobilizadas/metabolismo , Metilfenidato/análise , Metilfenidato/metabolismo , Oxirredução , Trametes/enzimologia
12.
Int J Legal Med ; 131(6): 1543-1553, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28710651

RESUMO

The acute and chronic toxicity of several new psychoactive substances (NPS) is unknown, and only little information is available on the pharmacology and toxicology, toxicokinetics, and detectability in body samples of such new compounds. We here propose analytical methods to disclose acute and chronic use of two types of new psychostimulants: benzofurans and ethylphenidate and we applied them to a real case of a subject attending Emergency Department with signs of acute intoxication due to psychotropic drug(s). After a urinary immunoassay screening which gave a positivity to amphetamines, general unknown gas chromatography-mass spectrometry (GC-MS) urine analysis identified 5-(2-methylaminopropyl)benzofuran (5-MAPB), 5-(2-aminopropyl)benzofuran (5-APB), 5-(2-ethylaminopropyl)benzofuran (5-EAPB), ethylphenidate, and ritalinic acid. All these substances were confirmed and quantified not only in urine but also in serum samples at different times after hospitalization by GC-MS and ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Two subsequent 2-cm hair segments were also analyzed and tested positive for the above reported substances, evidencing repeated use. The matching quantitative results in all the analyzed biological matrices demonstrated that both analytical methodologies were suitable to correctly quantify NPS involved in the current intoxication. The objective assessment of acute and chronic intoxication by the above reported compounds demonstrate that the development of analytical methods aiming at the detection of a broad spectrum of compounds in conventional and non-conventional biological matrices is helpful when facing the new challenging threat of intoxications caused by NPS.


Assuntos
Benzofuranos/análise , Cabelo/química , Metilfenidato/análogos & derivados , Psicotrópicos/análise , Detecção do Abuso de Substâncias/métodos , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Benzofuranos/efeitos adversos , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Imunoensaio , Masculino , Metilfenidato/efeitos adversos , Metilfenidato/análise , Psicotrópicos/efeitos adversos , Espectrometria de Massas em Tandem , Adulto Jovem
13.
Neuropsychopharmacology ; 42(3): 682-694, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27534265

RESUMO

Agonist-replacement therapies have been successfully used for treatment of opiate and nicotine addiction, but not for cocaine addiction. One of the major obstacles is the cocaine-like addictive potential of the agonists themselves. We report here an atypical dopamine (DA) transporter (DAT) inhibitor, CTDP-32476, that may have translational potential for treating cocaine addiction. In vitro ligand-binding assays suggest that CTDP-32476 is a potent and selective DAT inhibitor and a competitive inhibitor of cocaine binding to the DAT. Systemic administration of CTDP-32476 alone produced a slow-onset, long-lasting increase in extracellular nucleus accumbens DA, locomotion, and brain-stimulation reward. Drug-naive rats did not self-administer CTDP-32476. In a substitution test, cocaine self-administration rats displayed a progressive reduction in CTDP-32476 self-administration with an extinction pattern of drug-taking behavior, suggesting significantly lower addictive potential than cocaine. Pretreatment with CTDP-32476 inhibited cocaine self-administration, cocaine-associated cue-induced relapse to drug seeking, and cocaine-enhanced extracellular DA in the nucleus accumbens. These findings suggest that CTDP-32476 is a unique DAT inhibitor that not only could satisfy 'drug hunger' through its slow-onset long-lasting DAT inhibitor action, but also render subsequent administration of cocaine ineffectual-thus constituting a novel and unique compound with translational potential as an agonist therapy for treatment of cocaine addiction.


Assuntos
Comportamento Animal/efeitos dos fármacos , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Proteínas da Membrana Plasmática de Transporte de Dopamina/antagonistas & inibidores , Inibidores da Captação de Dopamina/farmacologia , Núcleo Accumbens/metabolismo , Recompensa , Animais , Inibidores da Captação de Dopamina/administração & dosagem , Masculino , Metilfenidato/análise , Núcleo Accumbens/efeitos dos fármacos , Ratos , Ratos Long-Evans
14.
J Pharm Biomed Anal ; 117: 474-84, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26454340

RESUMO

Ethylphenidate is a new potent synthetic psychoactive drug, structurally related to methylphenidate. Using human liver microsomes and cytosol, we have investigated for the first time the Phase-I and Phase-II in vitro metabolism of ethylphenidate. The structure of the metabolites was elucidated by hybrid quadrupole time-of-flight mass spectrometry. Overall, seven Phase-I, but no Phase-II metabolites were detected. Ethylphenidate underwent hydroxylation forming two primary mono-hydroxylated metabolites and, subsequently, dehydration and ring opening with an additional hydroxylation, forming secondary metabolites. The involvement of different human cytochrome P450 (CYP) enzymes in the formation of ethylphenidate metabolites was investigated using a panel of human recombinant CYPs (rCYPs). rCYP2C19 was the most active recombinant enzyme involved in the formation of all seven ethylphenidate metabolites detected, although other rCYPs (rCYP1A2, rCYP2B6, rCYPC9, rCYP2D6, and rCYP3A4, but not rCYP2E1) played a role in the metabolism of ethylphenidate. All metabolites identified in the present study can be considered as potential specific biomarkers of ethylphenidate in toxicological studies. Additionally, ritalinic acid and methylphenidate were formed by non-enzymatic hydrolysis and trans-esterification, and, therefore, they cannot be considered as (oxidative) metabolites of ethylphenidate. The presence of methylphenidate and ritalinic acid cannot be exclusively associated to the use of ethylphenidate, since methylphenidate is a drug itself and ritanilic acid can be formed from both ethylphenidate and methylphenidate.


Assuntos
Metilfenidato/análogos & derivados , Microssomos Hepáticos/metabolismo , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Sistema Enzimático do Citocromo P-450/análise , Sistema Enzimático do Citocromo P-450/metabolismo , Humanos , Metilfenidato/análise , Metilfenidato/metabolismo , Microssomos Hepáticos/química
15.
Ther Drug Monit ; 38(1): 98-107, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26349081

RESUMO

BACKGROUND: For psychostimulants, a marked individual variability in the dose-response relationship and large differences in plasma concentrations after similar doses are known. Therefore, optimizing the efficacy of these drugs is at present the most promising way to exploit their full pharmacological potential. Moreover, it seems important to examine oral fluid as less invasive biological matrix for its benefit in therapeutic drug monitoring for patients with hyperkinetic disorder. METHODS: A high-performance liquid chromatography method for quantification of methylphenidate (MPH), dexamphetamine (DXA), and atomoxetine in serum and oral fluid has been developed and validated. The analytical procedure involves liquid-liquid extraction, derivatization with 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride as a label and chromatographic separation on a Phenomenex Gemini-NX C18 analytical column using gradient elution with water-acetonitrile. The derivatized analytes were detected at 330 nm (excitation wavelength) and 440 nm (emission wavelength). To examine the oral fluid/serum ratios, oral fluid samples were collected simultaneously to blood samples from patients with hyperkinetic disorder. RESULTS: The method allows quantification of all analytes in serum and oral fluid within 16 minutes under the same or similar conditions. Oral fluid/serum ratios for MPH and DXA were highly variable and showed an accumulation of these drugs in oral fluid. CONCLUSIONS: The developed method covers the determination of MPH, DXA, and atomoxetine concentrations in serum and oral fluid after the intake of therapeutic doses. Oral fluid samples are useful for the qualitative detection of MPH and DXA.


Assuntos
Cloridrato de Atomoxetina/análise , Cromatografia Líquida de Alta Pressão/métodos , Dextroanfetamina/análise , Metilfenidato/análise , Adolescente , Inibidores da Captação Adrenérgica/análise , Inibidores da Captação Adrenérgica/farmacocinética , Adulto , Cloridrato de Atomoxetina/farmacocinética , Estimulantes do Sistema Nervoso Central/análise , Criança , Dextroanfetamina/farmacocinética , Monitoramento de Medicamentos , Feminino , Humanos , Extração Líquido-Líquido , Masculino , Metilfenidato/farmacocinética , Pessoa de Meia-Idade , Espectrometria de Fluorescência/métodos , Adulto Jovem
16.
PLoS One ; 10(6): e0129805, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26107846

RESUMO

The ongoing bioethical debate on pharmacological cognitive enhancement (PCE) in healthy individuals is often legitimated by the assumption that PCE will widely spread and become desirable for the general public in the near future. This assumption was questioned as PCE is not equally save and effective in everyone. Additionally, it was supposed that the willingness to use PCE is strongly personality-dependent likely preventing a broad PCE epidemic. Thus, we investigated whether the cognitive performance and personality of healthy individuals with regular nonmedical methylphenidate (MPH) use for PCE differ from stimulant-naïve controls. Twenty-five healthy individuals using MPH for PCE were compared with 39 age-, sex-, and education-matched healthy controls regarding cognitive performance and personality assessed by a comprehensive neuropsychological test battery including social cognition, prosocial behavior, decision-making, impulsivity, and personality questionnaires. Substance use was assessed through self-report in an interview and quantitative hair and urine analyses. Recently abstinent PCE users showed no cognitive impairment but superior strategic thinking and decision-making. Furthermore, PCE users displayed higher levels of trait impulsivity, novelty seeking, and Machiavellianism combined with lower levels of social reward dependence and cognitive empathy. Finally, PCE users reported a smaller social network and exhibited less prosocial behavior in social interaction tasks. In conclusion, the assumption that PCE use will soon become epidemic is not supported by the present findings as PCE users showed a highly specific personality profile that shares a number of features with illegal stimulant users. Lastly, regular MPH use for PCE is not necessarily associated with cognitive deficits.


Assuntos
Estimulantes do Sistema Nervoso Central/farmacologia , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/psicologia , Metilfenidato/farmacologia , Nootrópicos/farmacologia , Personalidade , Adulto , Estimulantes do Sistema Nervoso Central/análise , Estimulantes do Sistema Nervoso Central/urina , Cognição , Tomada de Decisões , Empatia , Feminino , Cabelo , Voluntários Saudáveis , Humanos , Comportamento Impulsivo , Masculino , Metilfenidato/análise , Metilfenidato/urina , Testes Neuropsicológicos , Nootrópicos/análise , Nootrópicos/urina , Reprodutibilidade dos Testes , Recompensa , Comportamento Social , Apoio Social , Inquéritos e Questionários , Urina , Adulto Jovem
17.
Biomed Chromatogr ; 28(11): 1554-64, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25196779

RESUMO

Commercially available methylphenidate (MPH) exists as a racemic mixture composed of the d- and l-threo enantiomers. Various pharmacokinetic studies of MPH have shown a greater pharmacological potency of the d-threo enantiomer. Furthermore, it was deduced that the stereoselective cleavage of MPH to produce ritalinic acid (RA) by human carboxylesterase results in a higher oral bioavailability of the d-threo enantiomer. As a requirement for pharmaceutical regulation authorities, efforts have been made to determine the differential biological distribution of d- and l-threo MPH and RA enantiomers. In support of these efforts, numerous analytical procedures have been developed for the chiral separation and quantification of MPH enantiomers in a variety of biological matrices. The available methodologies accomplish the enantioseparation and quantification of MPH using gas chromatography, liquid chromatography or capillary electrophoretic techniques coupled with a variety of detectors. The current review discusses the technical procedures involved, and the sensitivity and selectivity of these assays.


Assuntos
Cromatografia Líquida , Eletroforese Capilar , Cromatografia Gasosa-Espectrometria de Massas , Metilfenidato/análise , Metilfenidato/química , Animais , Humanos , Camundongos , Estereoisomerismo
18.
Forensic Sci Int ; 243: 126-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25161162

RESUMO

Methylphenidate, a psychostimulant drug from the group of amphetamines is, among others, established in the treatment of attention deficit hyperactivity disorder and narcolepsy. It is also known to have a certain potential of abuse. In combination with alcohol, the metabolite ethylphenidate was detected in human plasma in small amounts. However, ethylphenidate is sold as "research chemical" via the Internet. It was put under German narcotics law in July 2013. In a recent case, where a deceased person was found in his apartment, the police seized a plastic bag with the inscription "ethylphenidate". An autopsy of the 32-year-old man yielded a mitral valve endocarditis, which must have persisted a while before death, in combination with a pneumonia. At the Forensic Toxicological Centre (FTC) in Munich femoral blood, liver, pericardium fluid, urine, stomach content and hair of the deceased were analyzed for ethylphenidate after sample preparation by an LC-Triple TOF 5600. Calibration curves were spiked with a methanolic 1mg/mL solution of ethylphenidate (substance provided by the State Office of Criminal Investigation in Munich) in whole blood in comparison to liver and femoral blood, in serum in comparison to pericardium fluid and in urine in comparison to urine and stomach content, respectively. Ethylphenidate was detected in all analyzed matrices. The spectrums of the human specimen were compared to those obtained from the calibration curves and identified as ethylphenidate. The measured concentrations were for femoral blood 110ng/mL, for liver 180ng/g, for pericardium fluid 131ng/mL, for urine 987ng/mL and for stomach content 20.7ng/mL, respectively. The stomach contained 200mL of a brownish-coloured liquid, resulting in a total amount of 4000ng ethylphenidate. The lowest calibrator for whole blood and serum was 1ng/mL and for urine 10ng/mL. As far as it is known to the authors, these are the first ethylphenidate levels measured in a case of ethylphenidate intake. Therefore these results can only be compared to methylphenidate concentrations with therapeutic levels ranging from 5 to 60ng/mL in serum. As the toxic levels for methylphenidate start from approximately 500ng/mL serum, we estimate that ethylphenidate in the concentrations mentioned above is not in a directly lethal range. But it has to be considered, that amphetamine-like drugs as methylphenidate are known for their cardiovascular side effects (like tachycardia and arrhythmia) and might therefore have contributed to death, which was attributed to endocarditis in combination with pneumonia.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Metilfenidato/análogos & derivados , Adulto , Endocardite/patologia , Conteúdo Gastrointestinal/química , Cabelo/química , Humanos , Fígado/química , Masculino , Metilfenidato/análise , Pericárdio/química , Pneumonia/patologia
19.
Forensic Sci Int ; 243: 1-13, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24769262

RESUMO

Our continuous survey of illegal products in Japan revealed the new distribution of 15 designer drugs. We identified four synthetic cannabinoids, i.e., NNEI (1), 5-fluoro-NNEI (2), 5-chloro-NNEI (3) and NNEI indazole analog (4), and seven cathinone derivatives, i.e., MPHP (5), α-PHPP (6), α-POP (7), 3,4-dimethoxy-α-PVP (8), 4-fluoro-α-PVP (9), α-ethylaminopentiophenone (10) and N-ethyl-4-methylpentedrone (11). We also determined LY-2183240 (12) and its 2'-isomer (13), which were reported to inhibit endocannabinoid uptake, a methylphenidate analog, 3,4-dichloromethylphenidate (14), and an MDA analog, 5-APDB (15). No chemical and pharmaceutical data for compounds 3, 4, 6 and 7 had been reported, making this the first report on these compounds.


Assuntos
Canabinoides/análise , Estimulantes do Sistema Nervoso Central/análise , Drogas Desenhadas/análise , Legislação de Medicamentos , Preparações de Plantas/química , Psicotrópicos/análise , Alcaloides/análise , Alcaloides/química , Canabinoides/química , Estimulantes do Sistema Nervoso Central/química , Drogas Desenhadas/química , Compostos Heterocíclicos com 1 Anel/análise , Japão , Metilfenidato/análogos & derivados , Metilfenidato/análise , Psicotrópicos/química , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Ureia/análogos & derivados , Ureia/análise
20.
J Forensic Sci ; 59(3): 847-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24502813

RESUMO

Methylphenidate (MPD) is a widely prescribed stimulant used primarily for the treatment for attention-deficit/hyperactivity disorder (ADHD). Suicide attempts involving MPD ingestion have been well described; however, deaths attributed solely to MPD ingestion have not been reported. A 62-year-old woman was found dead on her floor. The only discrepancy in among her medication quantities was that >three hundred 10 mg MPD tablets were missing. Analysis utilizing gas chromatography-mass spectrometry revealed elevated postmortem MPD peripheral and central blood, liver and vitreous humor concentrations. Considering both the central blood to peripheral blood ratio (0.89) and the liver to peripheral blood ratio (3.3), MPD does not appear subject to significant postmortem redistribution. With no other identifiable cause of death, we report what appears to be the first isolated MPD ingestion associated with a fatality.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Estimulantes do Sistema Nervoso Central/intoxicação , Metilfenidato/análise , Metilfenidato/intoxicação , Administração Oral , Estimulantes do Sistema Nervoso Central/farmacocinética , Feminino , Toxicologia Forense , Humanos , Fígado/química , Metilfenidato/farmacocinética , Pessoa de Meia-Idade , Mudanças Depois da Morte , Distribuição Tecidual , Corpo Vítreo/química
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