A Comparative Study Between Two Different Conventional Working Electrodes for Detection of Delta(9)-Tetrahydrocannabinol Using Square-Wave Voltammetry: a New Sensitive Method for Forensic Analysis

Autor(es)

Balbino, Marco A. ^[1] ; Eleoterio, Izabel C. ^[1] ; de Oliveira, Laura S. ^[1] ; de Menezes, Matheus M. T. ^[1] ; de Andrade, Jose Fernando ^[1] ; Ipolito, Antonio Jose ^[2] ; de Oliveira, Marcelo F. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Quim, Fac Filosofia Ciencias & Letras Ribeirao Preto, BR-14040901 Ribeirao Preto, SP - Brazil

^[2] Superintendencia Policia Tecn Cient Estado Sao Pa, Nucleo Pericias Criminalist Ribeirao Preto, BR-14015040 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Brazilian Chemical Society; v. 25, n. 3, p. 589-596, MAR 2014.
• Citações Web of Science: 6

Resumo

Marijuana is a widely consumed illicit drug. Therefore, drug dealers have sought new ways to mask its forensic (spot test) analysis. In this article we describe a methodology for delta-9-tetrahydrocannabinol (Delta(9)-THC) detection by square-wave voltammetric (SWV) analysis in organic medium (N,N-dimethylformamide) using tetrabutylammonium tetrafluoroborate (TBATFB) as supporting electrolyte, and glassy carbon and platinum disc as working electrode. Applying a potential of -0.5 +/- 0.01 V vs. Ag/AgCl, KCl(sat), we detected a well-defined anodic peak current after the pre-concentration step; Delta(9)-THC detection presented linear dependence at concentrations ranging from 1.0 x 10(-9) mol L-1 to 2.2 x 10(-8) mol L-1, with a linear correlation coefficient 0.999 and a detection limit of 6.2 x 10(-10) mol L-1, using the glassy carbon disc working electrode. These results confirm that optimized SWV technique using glassy carbon disc working electrode enables qualitative analysis of Delta(9)-THC at concentrations higher than 1.0 nmol L-1. (AU)

• Processo FAPESP: 12/00084-7 - Desenvolvimento de eletrodos quimicamente modificados para a determinação voltamétrica de cocaína, MDMA, LSD e D-9-tetraidrocanabinol em amostras de interesse judicial
• Beneficiário: Marcelo Firmino de Oliveira
• Modalidade de apoio: Auxílio à Pesquisa - Regular