Swift electrochemical sensing of diltiazem employing highly-selective molecularly-imprinted 3-amino-4-hydroxybenzoic acid

Author(s)

Sposito, Heitor Gabriel Martins ; Lobato, Alnilan ; Tasic, Nikola O. ; Maldaner, Adriano O. ; Paixao, Thiago R. L. C. ; Goncalves, Luis Moreira

• Document type: Journal article
• Source: JOURNAL OF ELECTROANALYTICAL CHEMISTRY; v. 911, p. 7-pg., 2022-03-11.

Abstract

Diltiazem is a calcium channel-blocking agent, efficient in treating various heart-related conditions and dis-eases. It has been used as a cutting agent in cocaine and prevents its common cardiotoxic effects. This paper presents a highly selective molecularly-imprinted sensor to detect diltiazem in buffer and urine. In addition, the possibility of using this sensor as a forensic tool for fingerprinting street-seized cocaine samples of hetero-geneous composition was investigated. With thorough optimization of the fabrication process, it was possible to obtain a sensible and reproducible analytical signal via square-wave voltammetry (SWV) as the electroana-lytical technique. The obtained analytical parameters for the samples in buffer, pH 7.4, were the limit of detec-tion (LOD) of 0.12 mu mol L-1, the limit of quantification (LOQ) of 0.41 mu mol L-1, and inter-day reproducibility of 2%. For the samples in artificial urine, the analytical parameters were LOD of 0.26 mu mol L-1, LOQ of 0.88 mu mol L-1, and inter-day reproducibility of 9%. Decent linearity of the analytical signal with the increased concentration of diltiazem in the cocaine street samples suggested a high perspective of the proposed sensor for the forensic laboratory applications, more precisely, the determination of the seized samples' origins. (AU)

• FAPESP's process: 18/13922-7 - Development of a point-of-care biosensor for the swift determination of D-Dimers
• Grantee: Nikola Tasic
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/14425-7 - A new synergetic path for gas-diffusion microextraction (GDME) making use of molecular imprinted polymers (MIPs)
• Grantee: Luís Francisco Moreira Gonçalves
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 19/16491-0 - Rapid, onsite detection of toxic metals combining paper-based electrochemical sensors and fast-scan cyclic voltammetry
• Grantee: Thiago Regis Longo Cesar da Paixão
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/11214-8 - Application of capillary electrophoresis for the determination of aldehydes after extraction by GDME-MIPs
• Grantee: Alnilan Cristina Barros Lobato
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 17/10522-5 - Development of alternative methods for fabrication of electrochemical paper-based sensors
• Grantee: Thiago Regis Longo Cesar da Paixão
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/08782-1 - Miniaturized and integrated chemical sensors: new fabrication platforms for biological, clinical and environmental applications
• Grantee: Mauro Bertotti
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 20/04268-1 - Electroanalytical determination of calcium channel blockers making use of molecularly imprinted polymers
• Grantee: Heitor Gabriel Martins Sposito
• Support Opportunities: Scholarships in Brazil - Scientific Initiation