Screening of seized cocaine samples using electrophoresis microchips with integrated contactless conductivity detection.
Electrophoresis
; 39(17): 2188-2194, 2018 09.
Article
em En
| MEDLINE
| ID: mdl-29947145
This study describes the development of a new analytical method for the separation and detection of cocaine (COC) and its adulterants, or cutting agents, using microchip electrophoresis (ME) devices coupled with capacitively coupled contactless conductivity detection (C4 D). All the experiments were carried out using a glass commercial ME device containing two pairs of integrated sensing electrodes. The running buffer composed of 20 mmol/L amino-2-(hydroxymethyl) propane-1,3-diol and 10 mmol/L 3,4-dimethoxycinnamic acid provided the best separation conditions for COC and its adulterants with baseline resolution (R > 1.6), separation efficiencies ranging from (2.9 ± 0.1) to (3.2 ± 0.2) × 105 plates/m, and estimated LOD values between 40 and 150 µmol/L. The quantification of COC was successfully performed in four samples seized by the Brazilian Federal Police Department and all predicted values agree with values estimated by the reference method. Some other interfering species were detected in the seized samples during the screening procedure on ME-C4 D devices. While lidocaine was detected in sample 3, the presence of levamisole was observed in samples 2 and 4. However, their concentrations were estimated to be below the LOQ. ME-C4 D devices have proved to be quite efficient for the identification and quantification of COC with errors lower than 10% when compared to the data obtained by a reference method. The approach herein reported offers great potential to be used for on-site COC screening in seized samples.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Detecção do Abuso de Substâncias
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Cocaína
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Eletroforese em Microchip
Tipo de estudo:
Diagnostic_studies
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Prognostic_studies
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Screening_studies
Idioma:
En
Revista:
Electrophoresis
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Alemanha