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1.
J Forensic Sci ; 69(3): 1025-1034, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38520078

RESUMEN

The area of forensic chemistry has been growing and developing as a line of research due to the high demands of public safety that require increasingly reliable results due to their importance in criminalistics. In this way, the development of new technologies that help this area, whether in the identification and quantification of drugs or the fight against fraud, becomes promising. In this context, the present work explored the production of reference standards from the purification of cocaine/crack samples seized by the Civil Police of the State of Espírito Santo. Cocaine was purified using chromatographic techniques, and benzoylecgonine was synthesized from purified cocaine. All substances were characterized by ultra-high-resolution mass spectrometry and nuclear magnetic resonance. Homogeneity and stability studies were also performed with benzoylecgonine, and the results were evaluated using analysis of variance (ANOVA). Cocaine and benzoylecgonine showed purities of 98.37% and 96.34%, respectively. The homogeneity of the batch, short-term stability, and other parameters were also evaluated, which together indicate this proposal as promising in the development of reference standards for drugs of abuse from samples seized by the Brazilian forensic police.


Asunto(s)
Cocaína/análogos & derivados , Drogas Ilícitas , Espectrometría de Masas , Estándares de Referencia , Humanos , Drogas Ilícitas/química , Espectroscopía de Resonancia Magnética , Toxicología Forense , Brasil , Cromatografía de Gases y Espectrometría de Masas
2.
J Forensic Sci ; 65(6): 2188-2193, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32777087

RESUMEN

The concentrations of lead (Pb), barium (Ba), and antimony (Sb), characteristic of GSR, were determined in soil sediments and immature (larvae) of cadaveric flies of the family Calliphoridae, by inductively coupled plasma mass spectrometry (ICP-MS). This research refers to a case study from two real crime scenes in which the corpses were in an advanced state of decomposition. In case 1, the victim had holes similar to gunshot wounds, and in case 2, there was no evidence of perforations in the corpse. Soil sediment collection was performed at three different points of the terrain, at a minimum distance of 10 m from the corpse, for cases 1 and 2. In relation to the collection of immatures, larvae were collected in regions of the mouth, nose, and orifices similar to the entry of firearms projectile into the body, for case 1, and collection of larvae and pupae, located on the body and underneath it, for case 2. It was possible to detect and quantify the three elements of interest (Pb, Ba, and Sb) by ICP-MS in both sediment and cadaveric larvae. Concentrations of 4.44, 8.74, and 0.08 µg/g were obtained for Pb, Ba, and Sb, respectively, in the soil for case 1. For the case 2, the concentrations in Pb, Ba, and Sb were from 16.34 to 26.02 µg/g; from 32.64 to 57.97 µg/g and from 0.042 to 0.30 µg/g, respectively. In the larvae, Pb, Ba, and Sb were quantified in cases 1 and 2 with a concentration of 6.28 and 1.78 µg/g for Pb, 1.49 and 2.94 µg/g for Ba, 0.50 µg/g and

Asunto(s)
Antimonio/análisis , Bario/análisis , Calliphoridae/química , Larva/química , Plomo/análisis , Pupa/química , Animales , Conducta Alimentaria , Entomología Forense , Humanos , Masculino , Espectrometría de Masas , Cambios Post Mortem , Heridas por Arma de Fuego
3.
J Mass Spectrom ; 55(10): e4596, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32729201

RESUMEN

The consumption of design drugs, frequently known as new psychoactive substances (NPS), has increased considerably worldwide, becoming a severe issue for the responsible governmental agencies. These illicit substances can be defined as synthetic compounds produced in clandestine laboratories in order to act as analogs of schedule drugs mimetizing its chemical structure and improving its pharmacological effects while hampering the control and making regulation more complicated. In this way, the development of new methodologies for chemical analysis of NPS drugs is indispensable to determine a novel class of drugs arising from the underground market. Therefore, this work shows the use of high-resolution mass spectrometry Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) applying different ionization sources such as paper spray ionization (PSI) and electrospray ionization (ESI) in the evaluation of miscellaneous of seized drugs samples as blotter paper (n = 79) and tablet (n = 100). Also, an elucidative analysis was performed by ESI(+)MS/MS experiments, and fragmentation mechanisms were proposed to confirm the chemical structure of compounds identified. Besides, the results of ESI(+) and PSI(+)-FT-ICR MS were compared with those of GC-MS, revealing that ESI(+)MS showed greater detection efficiency among the methodologies employed in this study. Moreover, this study stands out as a guide for the chemical analysis of NPS drugs, highlighting the differences between the techniques of ESI(+)-FT-ICR MS, PSI(+)-FT-ICR MS, and GC-MS.


Asunto(s)
Drogas de Diseño/química , Drogas Ilícitas/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Cromatografía de Gases y Espectrometría de Masas , Papel , Espectrometría de Masas en Tándem
4.
Rapid Commun Mass Spectrom ; 34 Suppl 3: e8747, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32056289

RESUMEN

RATIONALE: Ambient mass spectrometry techniques are much required in forensic chemistry to evaluate evidence with low analytical interference, high confidence, and accuracy. However, traditional methodologies, such as paper spray ionization, have been shown to present low sensitivity in the analysis of illicit drugs from biological matrices. METHODS: Fiber spray ionization mass spectrometry (FSI-MS) was developed using a capillary polypropylene (PP) hollow fiber. Seized samples of drugs, i.e. a tablet, blotter paper, hashish, and cocaine powder, were analyzed. Cocaine was quantified from whole urine by dipping the fiber directly into solution. FSI-MS was tested for the analysis of a sample of urine obtained from a drug abuse suspect. RESULTS: The FSI(+) analysis showed the detection of different types of synthetic drugs in tablet and blotter paper samples, e.g. amphetamine, cathinones, phenethylamines, and opioids, while pure cocaine and different types of coca alkaloids were identified from cocaine powder with good sensitivity and high mass accuracy. The hashish analysis by FSI(-) revealed signals of cannabinoids, cannabinoid acids, and cannabinoid derivatives, detected mainly as [M - H]- ions or chlorine adducts [M + Cl]- . The quantification of cocaine in whole urine showed good sensitivity and precision with limits of detection and quantification of 5.16 and 17.21 ng/mL, respectively, linearity above 0.999, and relative standard deviation below 2.71%. The evaluation of seized sample of urine showed the detection of cocaine with relative ion intensity greater than 36%, as well as the metabolites benzoylecgonine and cocaethylene with a relative intensity of 1.4% and 6%, respectively. CONCLUSIONS: The developed FSI-MS method has the potential to be applied to forensic sample evaluation as well as to determine illicit drugs from biological matrices in toxicological analysis. The use of a capillary PP fiber has advantages as an extractor agent and ionizing substrate, and also the feature of it being dipped directly into the sample, thus preserving the integrity of the sample, which makes this a very promising ambient mass spectrometry method and relevant to forensic chemistry.


Asunto(s)
Cocaína/orina , Drogas Ilícitas/análisis , Espectrometría de Masas/métodos , Analgésicos Opioides/análisis , Cannabinoides/análisis , Cannabis , Cocaína/análogos & derivados , Cocaína/análisis , Ciencias Forenses , Humanos , Drogas Ilícitas/orina , Límite de Detección , N-Metil-3,4-metilenodioxianfetamina/análisis , Sensibilidad y Especificidad , Solventes/química , Detección de Abuso de Sustancias/métodos , Comprimidos
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