title: The Application of Voltammetric Analysis of Δ(9) -THC for the Reduction of False Positive Results in the Analysis of Suspected Marijuana Plant Matter.
abstract: The development of methodologies using inexpensive, fast, and reliable instrumention is desirable in illicit drug analysis. The purpose of this study was based on cyclic voltammetry technique to differentiate the electrochemical behavior of ∆(9) -THC, the psychoactive substance in marijuana, and five different extract plants to yield false positive results after analysis protocol for cannabinoids using thin-layer chromatography and Fast Blue B salt. After applying a deposition potential of -0.5 V in a glassy carbon working electrode, the results indicated an anodic peak current at 0.0 V versus Ag/AgCl after addition of ∆(9) -THC solution in the electrochemical cell, and limits of detection and quantification were 1.0 ng mL(-1) and 3.5 ng mL(-1) , respectively. Other interfering plants showed distinct amperometric responses. This methodology was useful to detect ∆(9) -THC even in the presence of the Fast Blue B salt, which avoided false positive results for all the studied extract plants.
authors.affiliation: Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Ribeirão Preto, SP, Brasil.
authors.forename: Marco A
authors.initials: MA
authors.lastname: Balbino
authors.affiliation: Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Ribeirão Preto, SP, Brasil.
authors.forename: Laura S
authors.initials: LS
authors.lastname: de Oliveira
authors.affiliation: Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Ribeirão Preto, SP, Brasil.
authors.forename: Izabel C
authors.initials: IC
authors.lastname: Eleotério
authors.affiliation: Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Ribeirão Preto, SP, Brasil.
authors.forename: Erica N
authors.initials: EN
authors.lastname: Oiye
authors.affiliation: Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Ribeirão Preto, SP, Brasil.
authors.forename: Maria F M
authors.initials: MF
authors.lastname: Ribeiro
authors.affiliation: Chemistry Department, International Forensic Research Institute, Florida International University, Miami, FL.
authors.forename: Bruce R
authors.initials: BR
authors.lastname: McCord
authors.affiliation: Superintendência de Polícia Técnico-Científica do Estado de São Paulo, Núcleo de Perícias Criminalísticas de Ribeirão Preto, 14015-040, Ribeirão Preto, SP, Brasil.
authors.forename: Antonio J
authors.initials: AJ
authors.lastname: Ipolito
authors.affiliation: Departamento de Química, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, 14040-901, Ribeirão Preto, SP, Brasil.
authors.forename: Marcelo F
authors.initials: MF
authors.lastname: de Oliveira
mesh_terms: D002186:Cannabinoids / Q000032:analysis*; D002188:Cannabis / Q000737:chemistry*; D013759:Dronabinol / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry
chemical_list: D002186:Cannabinoids; D013759:Dronabinol
keywords: Fast Blue B; cyclic voltammetry; false positive; forensic chemistry; forensic electroanalysis; forensic science; Δ9-tetrahydrocannabinol