Fe(II), Ni(II), Cu(II), and Co(II) salen Schiff base complexes: Proposal for a voltammetric sensor to analyze cocaine hydrochloride and its interferents

Autor(es)

Castro, Alex Soares ^{[1, 2]} ; Pinke Rodrigues, Caio Henrique ^{[2, 3]} ; Teles de Menezes, Matheus Manoel ^[4] ; Defendi da Silva, Ana Beatriz ^[1] ; Bruni, Aline Thais ^{[2, 3]} ; de Oliveira, Marcelo Firmino ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, Grp Eletroquim Eletroanalit & Quim Forense, Ave Bandeirantes 3900, Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Quim, Lab Estudos Interdisciplinares Direito Quim, Ave Bandeirantes 3900, Ribeirao Preto, SP - Brazil

^[3] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Inst Nacl Ciencia & Tecnol Forense INCT Forense, Dept Quim, Ave Bandeirantes 3900, Ribeirao Preto, SP - Brazil

^[4] Inst Fed Educ Ciencia & Tecnol Sao Paulo, Campus Catanduva, Catanduva, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: FORENSIC CHEMISTRY; v. 25, AUG 2021.
• Citações Web of Science: 1

Resumo

Given the fast-growing demand for anti-trafficking measures, this article investigates the development of voltammetric sensors for the oxidation of cocaine hydrochloride on the surface of carbon paste electrodes chemically modified with Schiff base complexes and their potential use for cocaine detection and quantification in seized samples. Voltammetric analyses revealed that {[}CoII(salen)] displayed amperometric and thermal stability, was uniformly distributed on the electrode surface, was only degraded at temperatures above 300 degrees C, and did not undergo passivation in acid medium. The {[}CoII(salen)]-modified voltammetric sensor gave error below 10%, an improvement on HPLC. SIMCA chemometric analyses predicted the group belonging to cocaine hydrochloride and its interferents effectively, attesting to the good selectivity and specificity of the developed sensor. The sensor has potential application in forensic investigations: its LOD and LOQ, intra and inter-day precision, accuracy, linearity ranges, selectivity, specificity, and sensitivity are better as compared to other chemically modified electrodes. Finally, the Density Functional Theory (DFT) method confirmed the oxidation-reduction mechanisms proposed in the literature. (AU)

• Processo FAPESP: 16/01447-7 - Desenvolvimento de eletrodos quimicamente modificados (EQMs) com complexos do tipo Base de Schiff para determinação de cocaína: estudos voltamétricos e aplicação da Teoria do Funcional de Densidade (TFD)
• Beneficiário: Alex Soares Castro
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 16/23825-3 - Desenvolvimento de sensores voltamétricos para determinação de cocaína e delta-9-tetraidrocanabinol em amostras apreendidas pela polícia
• Beneficiário: Marcelo Firmino de Oliveira
• Modalidade de apoio: Auxílio à Pesquisa - Regular