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1.
Forensic Sci Int ; 338: 111393, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35908338

RESUMO

Fentanyl has played a significant role in the opioid crisis, proving to be a persistent problem due to its analgesic effects and addictive nature. Consequently, fentanyl analogs have been identified as a rising threat in the illicit drug market, contributing to thousands of both fatal and nonfatal overdoses in the United States. A profile of the fentanyl and fentanyl analogs present in Washington D.C. was developed by analyzing syringe extracts obtained from needle-exchange programs in the city. Gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring (SIM) acquisition provided a targeted analysis scheme to detect trace amounts of nine compounds: acetyl fentanyl, para-fluorofentanyl, fentanyl, methoxyacetyl fentanyl, meta-chlorofentanyl, carfentanil, valeryl fentanyl, beta-hydroxythiofentanyl, and furanyl fentanyl. In total, 332 syringe extracts were analyzed. The detected analytes and their percent prevalences were fentanyl (72.29 %), acetyl fentanyl (11.44 %), para-fluorofentanyl (6.63 %), and furanyl fentanyl (3.61 %). Tandem use was detected with combinations of fentanyl with acetyl fentanyl (12.08 %), fentanyl with para-fluorofentanyl (7.08 %), fentanyl with furanyl fentanyl (4.58 %), and fentanyl with acetyl fentanyl and para-fluorofentanyl (2.08 %). The identities of the analogs present, their relative potencies, and tandem use trends provides valuable information, especially for medical personnel who respond to opioid-related overdoses and deaths. Based on the fentanyl analog trends and tandem use of these compounds revealed in this study, it is recommended that Congress passes the permanent classification of fentanyl analogs as Schedule I drugs.


Assuntos
Seringas , Espectrometria de Massas em Tandem , Analgésicos Opioides/análise , Fentanila , Humanos , Washington
2.
J Sep Sci ; 40(17): 3545-3556, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28683184

RESUMO

A comparison of ultra high performance supercritical fluid chromatography, ultra high performance liquid chromatography, and gas chromatography for the separation of synthetic cathinones has been conducted. Nine different mixtures of bath salts were analyzed in this study. The three different chromatographic techniques were examined using a general set of controlled synthetic cathinones as well as a variety of other synthetic cathinones that exist as positional isomers. Overall 35 different synthetic cathinones were analyzed. A variety of column types and chromatographic modes were examined for developing each separation. For the ultra high performance supercritical fluid chromatography separations, analyses were performed using a series of Torus and Trefoil columns with either ammonium formate or ammonium hydroxide as additives, and methanol, ethanol or isopropanol organic solvents as modifiers. Ultra high performance liquid chromatographic separations were performed in both reversed phase and hydrophilic interaction chromatographic modes using SPP C18 and SPP HILIC columns. Gas chromatography separations were performed using an Elite-5MS capillary column. The orthogonality of ultra high performance supercritical fluid chromatography, ultra high performance liquid chromatography, and gas chromatography was examined using principal component analysis. For the best overall separation of synthetic cathinones, the use of ultra high performance supercritical fluid chromatography in combination with gas chromatography is recommended.

3.
Drug Test Anal ; 9(10): 1512-1521, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28087976

RESUMO

The utility of diode array ultraviolet (UV) detection for aiding in the identification of synthetic cathinones, including different sub-classes and positional isomers is presented. For 35 synthetic cathinones, unique UV spectra are obtained for seven sub-classes, including mostly beta ketones, where position and type of substitution on benzene rings give rise to differences in UV maxima and relative intensity of the spectral bands. This aspect is key to distinguishing positional isomers that contain differences in R substitution (mono and di) around the benzene ring, which provides complementary information to electron ionization mass spectrometry, where the latter technique cannot distinguish between these types of positional isomers. In addition, it is possible to ascertain the substitution position based on the UV spectra. For ten sets of positional isomers, it was possible to distinguish most of the positional isomers within a set. For ultra-high performance supercritical fluid chromatography (UHPSFC) versus reversed phase ultra-high performance liquid chromatography (UHPLC), there was at least a 10 nm blue shift in UV maximum (shift to shorter wavelengths). This highlights the importance of taking in account the effect of mobile phase on the UV maximum when performing method development in UHPSFC. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Alcaloides/química , Estimulantes do Sistema Nervoso Central/química , Drogas Desenhadas/química , Espectrometria de Massas/métodos , Alcaloides/isolamento & purificação , Estimulantes do Sistema Nervoso Central/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico/métodos , Drogas Desenhadas/isolamento & purificação , Isomerismo , Raios Ultravioleta
4.
J Chromatogr A ; 1440: 201-211, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26947165

RESUMO

The recent development of modern methods for ultra high performance supercritical fluid chromatography (UHPSFC) has great potential for impacting the analysis of seized drugs. In the separation of synthetic cannabinoids the technique has the potential to produce superior resolution of positional isomers and diastereomers. To demonstrate this potential we have examined the capability of UHPSFC for the analysis of two different groups of synthetic cannabinoids. The first group was a mixture of 22 controlled synthetic cannabinoids, and the second group included JWH018 and nine of its non-controlled positional isomers The clear superiority of UHPSFC over other separation techniques was demonstrated, in that it was capable of near baseline separation of all 10 positional isomers using a chiral column. In total we examined four achiral columns, including Acquity UPC(2) Torus 2-PIC, Acquity UPC(2) Torus Diol, Acquity UPC(2) Torus DEA and Acquity UPC(2) Torus 1-AA (1.7µm 3.0×100mm), and three chiral columns, including Acquity UPC(2) Trefoil AMY1, Acquity UPC(2) Trefoil CEL1 and Acquity UPC(2) Trefoil CEL2 (2.5µm 3.0×150mm), using mobile phase compositions that combined carbon dioxide with methanol, acetonitrile, ethanol or isopropanol modifier gradients. Detection was performed using simultaneous PDA UV detection and quadrupole mass spectrometry. The orthogonality of UHPSFC, GC and UHPLC for the analysis of these compounds was demonstrated using principal component analysis. Overall we feel that this new technique should prove useful in the analysis and detection of seized drug samples, and will be a useful addition to the compendium of methods for drug analysis.


Assuntos
Canabinoides/análise , Técnicas de Química Analítica/métodos , Cromatografia com Fluido Supercrítico/normas , Dióxido de Carbono/química , Técnicas de Química Analítica/normas , Etanol/química , Espectrometria de Massas , Metanol/química , Análise de Componente Principal
5.
Forensic Sci Int ; 249: 83-91, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25679986

RESUMO

Separation and mass spectrometric techniques are integral parts of forensic drug analysis for both screening and confirmation. The Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG), which is responsible for setting standards for drug analysis, requires for drug identification a Category A test such as mass spectrometry with an additional test from either Category B or C. If a Category A method is not used at least two uncorrelated tests from Category B must be included, for which separation techniques such as gas chromatography and liquid chromatography would qualify. The utility and validity of using ultra high performance liquid chromatography (UHPLC) and time-of-flight (TOF) mass spectrometry (MS) for the analysis of synthetic cannabinoids is presented. The separation of 32 solutes, including 23 controlled substances and nine non-controlled positional isomers of JWH-018, are compared using UHPLC with TOF detection and capillary GC with electron ionization (EI). For these solutes, the reversed phase UHPLC separation on three different 2.1 mm × 150 mm × 2.7 µm superficially porous (SPP) columns (C18, Phenyl-Hexyl and Dimethylpentafluorophenylpropyl (PFP)) compared favorably with the capillary gas chromatography (GC) separation using an Elite-5MS column 0.25 mm × 30 m × 0.25 µm. Principal component analysis revealed that all three UHPLC separations for the separation of the controlled substances are orthogonal to the capillary GC separation. It was also revealed by principal component analysis that the separation of JWH-018 and the nine non-controlled positional isomers for the various techniques were significantly more correlated than the separation of the controlled substances. Although most of the controlled synthetic cannabinoids gave unique TOF in-source collision-induced dissociation MS spectra and EI spectra, it was not possible to discriminate among the geometric isomers (CP47, 497, Epi CP47, 497; Cp47, 497 C8 homologue, Epi CP47, 497 C8 homologue). JWH-018 could be distinguished from the non-controlled isomers based on its EI spectra. In contrast, several of the non-controlled JWH-018 isomers give identical TOF in-source collision-induced dissociation MS spectra to JWH-018.


Assuntos
Canabinoides/análise , Cromatografia Líquida de Alta Pressão/métodos , Drogas Desenhadas/análise , Drogas Ilícitas/análise , Cromatografia Gasosa/métodos , Análise de Componente Principal , Reprodutibilidade dos Testes
6.
Forensic Sci Int ; 161(1): 47-51, 2006 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-16332420

RESUMO

Bloodstain pattern analysts are sometimes called upon to determine the point of origin of a pattern of bloodstains. A derivation of expressions for the uncertainties deltaX and deltaY in the coordinates of the point of origin P(X, Y) of two bloodstains on a surface has recently been published. These uncertainties were expressed in terms of the uncertainties in the measured distance between the bloodstains and the uncertainties in the angles of impact of the bloodstains. This paper extends the derivations in the previous work by expressing the uncertainties in the coordinates of the point of origin of two bloodstains in terms of the uncertainties in the length and width measurements from which the angles of impact of the bloodstains are calculated.


Assuntos
Manchas de Sangue , Modelos Biológicos , Fenômenos Biofísicos , Biofísica , Humanos
7.
Forensic Sci Int ; 155(2-3): 188-92, 2005 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-16226157

RESUMO

This paper presents a geometrical model for the ricochet of shotgun pellets from an intermediate target surface. The model predicts that after ricochet the shotgun pellet pattern will be elongated in the direction parallel to the intermediate target surface, as has been found in empirical studies. This paper also shows that the angle of impact theta of a mass of shotgun pellets with a target surface can be calculated without significant error from the width W and the length L of the pellet pattern using the formula: sin theta= W/L.

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