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1.
Molecules ; 26(4)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546439

RESUMO

The rapid diffusion of new psychoactive substances (NPS) presents unprecedented challenges to both customs authorities and analytical laboratories involved in their detection and characterization. In this study an analytical approach to the identification and structural elucidation of a novel synthetic cannabimimetic, quinolin-8-yl-3-[(4,4-difluoropiperidin-1-yl) sulfonyl]-4-methylbenzoate (2F-QMPSB), detected in seized herbal material, is detailed. An acid precursor 4-methyl-3-(4,4-difluoro-1-piperidinylsulfonyl) benzoic acid (2F-MPSBA), has also been identified in the same seized material. After extraction from the herbal material the synthetic cannabimimetic, also referred to as synthetic cannabinoid receptor agonists or "synthetic cannabinoids", was characterized using gas chromatography-mass spectrometry (GC-MS), 1H, 13C, 19F and 15N nuclear magnetic resonance (NMR) and high-resolution tandem mass spectrometry (HR-MS/MS) combined with chromatographic separation. A cheminformatics platform was used to manage and interpret the analytical data from these techniques.


Assuntos
Canabinoides/análise , Drogas Ilícitas/análise , Ressonância Magnética Nuclear Biomolecular , Canabinoides/síntese química , Canabinoides/química , Europa (Continente) , Drogas Ilícitas/síntese química , Drogas Ilícitas/química , Espectrometria de Massas em Tandem
2.
J Anal Toxicol ; 44(8): 803-810, 2020 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33313885

RESUMO

Drug degradation as a consequence of putrefactive bacterial activity is a well-known factor that affects the identification and quantitation of certain substances of forensic interest. Current knowledge on putrefaction-mediated degradation of drugs is, however, significantly lacking. This study aimed to investigate the degradation of 4-methylmethcathinone (4-MMC or mephedrone) and to detect its degradation products in putrefied biological matrices containing 4-MMC. The bacteria species Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Proteus vulgaris were grown in brain-heart infusion broth, spiked with 4-MMC and incubated at 37°C for 24 h. Postmortem human blood and fresh porcine liver macerate were also left to putrefy in sample tubes at room temperature for 1 week. Structural elucidation was based on modern spectroscopic analyses including the use of high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. All four putrefactive bacteria were capable of degrading 4-MMC extensively under the experimental conditions explored. Of particular interest was the discovery of a novel degradation product common to all four bacterial species, which was assigned as 2-hydroxy-1-(4-methylphenyl)propan-1-one (HMP) based on the spectroscopic data. This degradation product was detectable in both postmortem human blood and porcine liver samples. The stability of the identified degradation products, especially HMP, should be further investigated to assess their validity of serving as marker analytes for monitoring 4-MMC in postmortem toxicology.


Assuntos
Drogas Ilícitas/química , Metanfetamina/análogos & derivados , Animais , Biomarcadores , Cromatografia Líquida , Humanos , Fígado , Espectroscopia de Ressonância Magnética , Metanfetamina/química , Mudanças Depois da Morte , Suínos
3.
Forensic Sci Int ; 310: 110235, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32169668

RESUMO

The chemical and biochemical analysis of bodily fluids after death is an important thanatochemical approach to assess the cause and time since death. Vitreous humor (VH) has been used as a biofluid for forensic purposes since the 1960s. Due to its established relevance in toxicology, a literature review highlighting the use of VH with an emphasis on endogenous compounds has not yet been undertaken. VH is a chemically complex aqueous solution of carbohydrates, proteins, electrolytes and other small molecules present in living organisms; this biofluid is useful tool for its isolated environment, preserved from bacterial contamination, decomposition, autolysis, and metabolic reactions. The post-mortem analysis of VH provides an important tool for the estimation of the post-mortem interval (PMI), which can be helpful in determining the cause of death. Consequently, the present review evaluates the recent chemical and biochemical advances with particular importance on the endogenous compounds present at the time of death and their modification over time, which are valuable for the PMI prediction and to identify the cause of death.


Assuntos
Drogas Ilícitas/química , Corpo Vítreo/patologia , Autopsia , Patologia Legal , Humanos , Mudanças Depois da Morte , Corpo Vítreo/química
4.
J Anal Toxicol ; 44(3): 207-217, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31909808

RESUMO

Synthetic cannabinoids pose significant threats to public health and safety, as their implications in overdose and adverse events continue to arise in United States and around the world. Synthetic cannabinoids have seen several generations of chemically diverse structural elements, impacting potency and effects. These factors create new analytical challenges for forensic laboratories. This report describes an efficient liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) assay for the identification of synthetic cannabinoid parent compounds and metabolites, including real-time identification of emergent compounds, using a SCIEX TripleTOF® 5600+ with non-targeted SWATH® acquisition. Method validation evaluated precision/accuracy, limits of detection, interferences, processed sample stability and carryover, for which 19 parent compounds and 19 metabolites were tested. To demonstrate feasibility, de-identified blood sample extracts were acquired from a large forensic toxicology laboratory and analyzed using the validated LC-QTOF-MS assay. In mid-2018, 200 blood extracts were analyzed, demonstrating a 19% positivity rate with > 94% agreement rate with original testing. In addition, three newly discovered synthetic cannabinoids were identified, including 5F-MDMB-PICA, 4-cyano CUMYL-BUTINACA and 5F-EDMB-PINACA. These synthetic cannabinoids were previously unreported in forensic toxicology casework in the United States. 5F-MDMB-PICA has become the most prevalent synthetic cannabinoid in United States, as of early 2019. These results demonstrate the effectiveness of this assay and workflow in the identification and characterization of synthetic cannabinoids, as well as the usefulness of sample-mining using non-targeted mass acquisition by LC-QTOF-MS for the discovery of NPS. High resolution mass spectrometry should be considered when developing new or novel assays for synthetic cannabinoids.


Assuntos
Canabinoides/análise , Toxicologia Forense , Drogas Ilícitas/análise , Medicamentos Sintéticos/análise , Bioensaio , Canabinoides/química , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Drogas Ilícitas/química , Indazóis , Espectrometria de Massas , Medicamentos Sintéticos/química
5.
J Anal Toxicol ; 44(2): 140-148, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-31788682

RESUMO

New psychoactive substances are emerging on the illegal drug market. Synthetic opioids including fentanyl analogues are of special concern due to their high potency. This indicates the possibility of low drug concentrations in vivo and calls for sensitive analytical methods and identification of the most appropriate analytical targets. In this study the in vitro metabolism of ortho-, meta- and para-fluorofentanyl, three fluorinated derivatives of fentanyl, has been investigated using human hepatocytes and compared to the results from an authentic human urine sample. Based on knowledge on the metabolism of similar fentanyl analogues N-dealkylation and hydroxylation was hypothesized to be the most central pathways. The three fluorofentanyl isomers were incubated with pooled human hepatocytes at 1, 3 and 5 h. Liquid chromatography quadrupole time of flight mass spectrometry operating in data-dependent mode was used to analyse the hepatocyte samples, as well as the hydrolysed and non-hydrolysed authentic urine sample. Data were analysed by a targeted approach with a database of potential metabolites. The major metabolite formed in vitro was the N-dealkylation product norfluorofentanyl. In addition various hydroxylated metabolites, a N-oxide, dihydrodiol metabolites and a hydroxymethoxy metabolite were found. In total, 14 different metabolites were identified for each fluorofentanyl isomer. In the authentic urine sample, three metabolites were detected in addition to the ortho-fluorofentanyl parent compound, with hydroxymethoxy metabolite having the highest abundance followed by norfluorofentanyl and a metabolite hydroxylated on the ethylphenyl ring. This in vitro study showed that the metabolic pattern for ortho-, meta-, and para-fluorofentanyl was close to those previously reported for other fentanyl analogues. We suggest that the hydroxymethoxy metabolite and the metabolite hydroxylated on the ethylphenyl ring should be the metabolites primarily investigated in further studies to determine the most appropriate marker for intake of fluorofentanyl derivatives in urine drug screening for human subjects.


Assuntos
Fentanila/metabolismo , Hepatócitos/metabolismo , Drogas Ilícitas/metabolismo , Detecção do Abuso de Substâncias , Analgésicos Opioides , Cromatografia Líquida , Drogas Desenhadas , Fentanila/análogos & derivados , Fentanila/química , Humanos , Hidrólise , Hidroxilação , Drogas Ilícitas/química , Espectrometria de Massas , Microssomos Hepáticos
8.
Drug Test Anal ; 12(1): 53-66, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31454468

RESUMO

Substandard and falsified (SF) antimicrobials are gaining popularity in both developing and developed countries, posing a growing threat to public health. In general, the evaluation of SF antimicrobial drugs mainly focuses on the identification and quantification of the pharmaceutical active ingredients, ignoring other parameters of drug quality control. This study performed an in-depth characterization and hazard identification of suspected SF antimicrobial medicinal products encountered in Belgium. In this comprehensive evaluation, impurity tests and dissolution studies were carried out. The dissolution profiles of illegal SF antimicrobials were mathematically compared to their genuine counterparts using the f1 and f2 -factor. The results indicated that 17 out of 57 illegal samples contained higher than permitted amounts of impurities and clearly demonstrated low equivalences of dissolution profiles between SF antimicrobials and genuine products. The variations between tablets at the different time points of the dissolution curves were also higher for the SF medicines. Moreover, 11 out of 19 illegal samples failed to meet the dissolution criteria prescribed by the United States Pharmacopeia. As impurities may induce adverse reactions and improper dissolution patterns may be the cause of insufficient drug efficacy, aggravation of illness and even promotion of antimicrobial resistance can be expected.


Assuntos
Anti-Infecciosos/química , Medicamentos Falsificados/química , Bélgica , Contaminação de Medicamentos , Liberação Controlada de Fármacos , Drogas Ilícitas/química , Controle de Qualidade , Comprimidos
9.
Forensic Sci Int ; 306: 110043, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31743834

RESUMO

3',4'-methylenedioxy-2,2-dibromobutyrophenone has been identified and fully characterized in a sample obtained from an anonymous consumer acquired as ketamine through the Internet market. The substance has been deeply characterized by using standard and high performance analytical techniques such as: attenuated total reflectance-infrared spectroscopy, gas chromatography-mass spectrometry, high-resolution mass spectrometry, elemental analysis, and nuclear magnetic resonance, including 1H, 13C, distortionless enhancement by polarization transfer, two dimensional homonuclear 1H-1H correlation spectroscopy, and 1H-13C heteronuclear single-quantum correlation spectra. 3',4'-methylenedioxy-2,2-dibromobutyrophenone is a precursor or intermediate in the synthesis of several synthetic cathinone derivatives, such as pentylone and methylenedioxy pyrovalerone. It is expected that 3',4'-methylenedioxy-2,2-dibromobutyrophenone does not act as psychoactive substance through disruption nor dysregulation of central and peripheral nervous systems, due to the absence of the characteristic amine group of cathinone derivatives. Although it cannot be considered a trend in new psychoactive substances consumption, the presence in the market and the unknown toxicity of this substance makes it a relevant fact.


Assuntos
Alcaloides/química , Butirofenonas/química , Medicamentos Falsificados , Drogas Desenhadas/química , Psicotrópicos/química , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Drogas Ilícitas/química , Internet , Ketamina , Espectroscopia de Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier
10.
J Pharm Biomed Anal ; 179: 112967, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31732403

RESUMO

The abuse of Novel Psychoactive Substances (NPS) still cause severe problems. A lot of them contain a stereogenic centre which leads to possible different pharmacological effects of the enantiomers. The aim of this study was to establish an enantioselective HPLC-UV method with applicability to a broad spectrum of NPS. Different compound classes including mainly amphetamines, cathinones, ketamines, pyrovalerones and benzofuries were tested for successful enantioseparation by one common chromatographic condition. All NPS samples were bought in various internet stores, were sythesized inhouse or were seized by the Austrian police. A commercially available Phenomenex LUX® AMP 3 µm, 150 × 4,6 mm column served as chiral stationary phase (CSP) for the enantiomeric separation experiments. This CSP has been developed particularly for enantioresolution of high abundant synthetic chiral drugs such as MDMA and amphetamine. All measurements were performed under isocratic conditions. For method optimisation, the effects of different mobile phase compositions, different pH values and temperatures on enantioseparation were investigated. Final mobile phase consisted of ammonium bicarbonate solution (5 mM) adjusted with concentrated ammonia to a pH of 11.3 mixed with acetonitrile in a ratio of 70:30. All in all, 83 of 95 analysed NPS were separated in their enantiomers successfully within 40 min. Furthermore, the method was found to be suitable for simultaneous enantioseparations, for enantiomeric elution order determinations, enantiomeric purity checks and for positional isomer separations. To prove the repeatability of the method, an intra- and an interday validation was performed successfully. By means of the wide applicability of the chosen column all separated NPS were shown to be traded as racemic mixtures.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Drogas Ilícitas/análise , Psicotrópicos/análise , Concentração de Íons de Hidrogênio , Drogas Ilícitas/química , Psicotrópicos/química , Estereoisomerismo , Temperatura
11.
Drug Test Anal ; 12(3): 297-315, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31854124

RESUMO

Synthetic cannabinoid receptor agonists (SCRAs) first appeared on the international recreational drug market in the early 2000s in the form of SCRA-containing herbal blends. Due to the cannabimimetic effects associated with the consumption of SCRAs, they have acquired an ill-informed reputation for being cheap, safe, and legal alternatives to illicit cannabis. Possessing high potency and affinity for the human cannabinoid receptor subtype-1 (CB1 ) and -2 (CB2 ), it is now understood that the recreational use of SCRAs can have severe adverse health consequences. The major public health problem arising from SCRA use has pressed legislators around the world to employ various control strategies to curb their recreational use. To circumvent legislative control measures, SCRA manufacturers have created a wide range of SCRA analogs that contain, more recently, previously unencountered azaindole, γ-carbolinone, or carbazole heterocyclic scaffolds. At present, little information is available regarding the chemical syntheses of these newly emerging classes of SCRA, from a clandestine perspective. When compared with previous generations of indole- and indazole-type SCRAs, current research suggests that many of these heterocyclic SCRA analogs maintain high affinity and efficacy at both CB1 and CB2 but largely evade legislative control. This review highlights the importance of continued research in the field of SCRA chemistry and pharmacology, as recreational SCRA use remains a global public health issue and represents a serious control challenge for law enforcement agencies.


Assuntos
Agonistas de Receptores de Canabinoides/química , Agonistas de Receptores de Canabinoides/farmacologia , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Animais , Agonistas de Receptores de Canabinoides/síntese química , Compostos Heterocíclicos/síntese química , Humanos , Drogas Ilícitas/síntese química , Drogas Ilícitas/química , Drogas Ilícitas/farmacologia , Estrutura Molecular
12.
J Anal Toxicol ; 44(2): 163-172, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-31424078

RESUMO

A method was developed for quantitative estimation of illicit psychostimulants in blood, with an emphasis on new psychoactive substances, based on gas chromatography nitrogen chemiluminescence detection coupled with atmospheric pressure chemical ionization quadrupole time-of-flight mass spectrometry (GC-NCD-APCI-QTOFMS). Quantitative estimation relied on the NCD's N-equimolar response to nitrogen, using amphetamine, 3,4-methylenedioxymethamphetamine (MDMA) and methylenedioxypyrovalerone as external calibrators for prim-, sec- and tert- amines, respectively. After spiking with 38 stimulants at 3 concentration levels, the donor blood samples were submitted to liquid-liquid extraction at a basic pH followed by acylation with trifluoroacetic anhydride. All but 3 psychostimulants could be analyzed with a limit of quantification (LOQ) of 0.05 mg/L. At LOQ, the coefficient of variation (CV) values for between-day accuracy was 62.3-143.3% (mean, 93.5%; median, 88.5%) and precision 6.6-22.4% (mean, 15.8%; median, 16.1%). In addition, 11 post-mortem blood samples, containing 0.08-2.4 mg/L of amphetamine (n = 5), methamphetamine (n = 4) or MDMA (n = 4), were analyzed by the GC-NCD-APCI-QTOFMS method, and the results were compared with an established electron ionization GC-MS method with appropriate calibration. The agreement between the 2 methods was 62.5-117.3%. Regarding identification, the APCI source permitted detection of the intact precursor ion, or the respective acylation product, for all of the measured compounds. The GC-NCD-APCI-QTOFMS method developed here enables instant quantitative estimation of illicit psychostimulants in blood at reasonable accuracy, without the necessity of possessing the true reference standards for each analyte.


Assuntos
Estimulantes do Sistema Nervoso Central/análise , Drogas Ilícitas/análise , Anfetamina/análise , Anfetamina/química , Benzodioxóis/análise , Benzodioxóis/química , Calibragem , Estimulantes do Sistema Nervoso Central/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Drogas Ilícitas/química , Luminescência , Metanfetamina/análise , Metanfetamina/química , N-Metil-3,4-Metilenodioxianfetamina/análise , N-Metil-3,4-Metilenodioxianfetamina/química , Nitrogênio , Pirrolidinas/análise , Pirrolidinas/química , Detecção do Abuso de Substâncias
13.
J Craniomaxillofac Surg ; 47(12): 1918-1921, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31812305

RESUMO

Krokodil is a cheap and effective home-made substitute for heroin. It is widely used over the territory of the former USSR (Russia, Ukraine, Armenia and others). Krokodil drug-related midface ON often occurs as a complication of maxillary ON. Treatment of Krokodil drug-related ON of the midface is challenging. It is difficult to determine the ON zone preoperatively and intraoperatively, due to the complex anatomy of the midface and the different periods of the disease onset in different areas. The aim of this study is to show variations of the clinical course and treatment options of Krokodil drug-related ON of the midface. In this study, 3 cases of Krokodil drug-related midface ON are reported. The main clinical feature of midface ON is extraoral fistula in the midfacial zone with purulent discharge or extraoral exposure of zygomatic bone. Surgery is the main treatment method for Krokodil drug-related midface osteonecrosis. Surgery includes necrotic bone removal and defect closure. Usually an extraoral approach is used to expose necrotic bone. Intraoral maxillary sinus floor defect is closed with the use of a buccal fat pad to prevent formation of oroantral communication. Drug withdrawal, radical necrectomy, and proper closure of formed defects are the main factors that lead to successful treatment of Krokodil drug-related midface ON patients.


Assuntos
Codeína/análogos & derivados , Drogas Ilícitas/efeitos adversos , Drogas Ilícitas/química , Necrose/induzido quimicamente , Osteonecrose/induzido quimicamente , Levantamento do Assoalho do Seio Maxilar , Abuso de Substâncias por Via Intravenosa/complicações , Adulto , Codeína/efeitos adversos , Codeína/química , Humanos , Masculino , Maxila , Pessoa de Meia-Idade , Necrose/cirurgia , Osteonecrose/cirurgia , Resultado do Tratamento
14.
Drug Test Anal ; 11(11-12): 1675-1697, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31758732

RESUMO

Follistatin, a myostatin-inhibiting protein, is prohibited according to chapter S4 of the "WADA 2019 List of Prohibited Substances and Methods". While currently no approved pharmaceutical formulations of follistatin are available, follistatin can be bought on the black market. Most of the products are labeled "follistatin 344" (FS344), a few "follistatin 315". A study on FS344 black market products was performed and an electrophoretic detection method for serum and urine developed. While only nine of the 17 tested products actually contained follistatin, in some of the others growth promoting peptides were found (e.g. MGF, GHRP-2). Surprisingly, all nine products contained His-tagged FS344 and a high degree of its oligomers. The detection method is based on immunomagnetic purification followed by SDS-PAGE and Western blotting with a monoclonal anti-His antibody. Alternatively, a monoclonal anti-follistatin antibody can be used. For immunoprecipitation (IP), a polyclonal anti-follistatin antibody is applied. An evaluation of suitable antibodies for IP and immunoblotting is also presented. Furthermore, practically all currently available follistatin standards were investigated. The detection limit of the method for black market FS344 in urine is ca 0.1 ng/mL for 10 mL. For a sample volume of 100 µL, an LOD of 5 ng/mL could be achieved for serum. Due to the presence of His-tags an unambiguous differentiation from endogenous follistatin is possible.


Assuntos
Folistatina/análise , Drogas Ilícitas/química , Sequência de Aminoácidos , Anticorpos/química , Western Blotting/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Folistatina/isolamento & purificação , Células HEK293 , Humanos , Imunoprecipitação/métodos , Isoformas de Proteínas/análise , Isoformas de Proteínas/isolamento & purificação
16.
J Am Chem Soc ; 141(42): 16763-16771, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31577900

RESUMO

Programming and controlling molecular recognition in aqueous solutions is increasingly common, but creating supramolecular sensors that detect analytes in biologically relevant solutions remains a nontrivial task. We report here a parallel synthesis-driven approach to create a family of self-assembling dimeric sensors that we call DimerDyes and its use for the rapid identification of salt-tolerant sensors for illicit drugs. We developed an efficient method that involves parallel synthesis and screening in crude form without the need to purify each potential sensor. Structurally diverse "hit" DimerDyes were resynthesized and purified and were each shown to assemble into homodimers in water in the programmed way. DimerDyes provided a "turn-on" fluorescence detection of multiple illicit drugs at low micromolar concentrations in water and in saliva. The combination of multiple agents into a sensor array was successfully able to detect and discriminate between closely related drugs and metabolites in multiple important drug families.


Assuntos
Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Drogas Ilícitas/análise , Saliva/química , Técnicas de Química Sintética , Dimerização , Humanos , Drogas Ilícitas/química , Espectrometria de Fluorescência
17.
Biosensors (Basel) ; 9(4)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31581533

RESUMO

Aptamer-based point-of-care (POC) diagnostics platforms may be of substantial benefit in forensic analysis as they provide rapid, sensitive, user-friendly, and selective analysis tools for detection. Aptasensors have not yet been adapted commercially. However, the significance of the applications of aptasensors in the literature exceeded their potential. Herein, in this review, a bottom-up approach is followed to describe the aptasensor development and application procedure, starting from the synthesis of the corresponding aptamer sequence for the selected analyte to creating a smart surface for the sensitive detection of the molecule of interest. Optical and electrochemical biosensing platforms, which are designed with aptamers as recognition molecules, detecting abused drugs are critically reviewed, and existing and possible applications of different designs are discussed. Several potential disciplines in which aptamer-based biosensing technology can be of greatest value, including forensic drug analysis and biological evidence, are then highlighted to encourage researchers to focus on developing aptasensors in these specific areas.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Ciências Forenses/métodos , Drogas Ilícitas/química , Detecção do Abuso de Substâncias/métodos , Colorimetria , Técnicas Eletroquímicas , Sistemas Automatizados de Assistência Junto ao Leito , Técnica de Seleção de Aptâmeros
18.
Sensors (Basel) ; 19(16)2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31443204

RESUMO

Screening of illicit drugs for new psychoactive substances-namely cathinone-at crime scenes is in high demand. A dual-emission bovine serum albumin-stabilized gold nanoclusters probe was synthesized and used for quantitation and screening of 4-chloromethcathinone and cathinone analogues in an aqueous solution. The photoluminescent (PL) color of the bovine serum albumin-stabilized Au nanoclusters (BSA-Au NCs) probe solution changed from red to dark blue during the identification of cathinone drugs when excited using a portable ultraviolet light-emitting diodes lamp (365 nm). This probe solution allows the PL color-changing point and limit of detection down to 10.0 and 0.14 mM, respectively, for 4-chloromethcathinone. The phenomenon of PL color-changing of BSA-Au NCs was attributed to its PL band at 650 nm, quenching through an electron transfer mechanism. The probe solution was highly specific to cathinone drugs, over other popular illicit drugs, including heroin, cocaine, ketamine, and methamphetamine. The practicality of this BSA-Au NCs probe was assessed by using it to screen illicit drugs seized by law enforcement officers. All 20 actual cases from street and smuggling samples were validated using this BSA-Au NCs probe solution and then confirmed using gas chromatography-mass spectrometry. The results reveal this BSA-Au NCs probe solution is practical for screening cathinone drugs at crime scenes.


Assuntos
Alcaloides/isolamento & purificação , Técnicas Biossensoriais , Drogas Ilícitas/isolamento & purificação , Alcaloides/química , Animais , Bovinos , Colorimetria , Humanos , Drogas Ilícitas/química , Nanoestruturas/química , Soroalbumina Bovina/química
20.
Mikrochim Acta ; 186(8): 525, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31292777

RESUMO

An electroanalytical method for determining dienestrol (DNL) in bovine urine samples is described. A glassy carbon electrode (GCE) modified with silver nanoparticles and functionalized multi-walled carbon nanotubes was used as working sensor. The modified GCE displays substantial analytical improvements including an amplified signal, fast electron transfer kinetics, and resistance to fouling. The irreversible oxidation signal of DNL is pH-dependent. Best reactivity is found at pH 3.0, where a typical anodic peak is recorded at 0.8 V (vs. Ag/AgCl). Square-wave voltammetry revealed a 8.4 nM detection limit (1.9 µg L-1), good repeatability and reproducibility (RSDs <5.0%), and good accuracy (93.2-99.4% recovery from spiked samples). The modified electrode is highly stable even in the presence of ions (Na+ and K+), urea and uric acid. The electrochemical sensor fulfills all requisites to be used as forensic device in surveillance of illegal livestock practices. Graphical abstract Schematic presentation of the construction of a glassy carbon electrode modified with silver nanoparticles and functionalized multi-walled carbon nanotubes. This sensor exhibited a remarkable performance for voltammetric detection of the illicit growth promoter dienestrol in animal urine.


Assuntos
Dienestrol/urina , Drogas Ilícitas/urina , Nanopartículas Metálicas/química , Nanotubos de Carbono/química , Prata/química , Animais , Bovinos , Dienestrol/química , Técnicas Eletroquímicas , Eletrodos , Drogas Ilícitas/química
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