| Full text | |
| Author(s): |
Ameku, Wilson A.
[1]
;
de Araujo, William R.
[2]
;
Rangel, Clara J.
[1]
;
Ando, Romulo A.
[1]
;
Paixao, Thiago R. L. C.
[1]
Total Authors: 5
|
| Affiliation: | [1] Univ Sao Paulo, Inst Chem, BR-05508000 Sao Paulo, SP - Brazil
[2] State Univ Campinas UNICANIP, Dept Analyt Chem, Inst Chem, BR-13083970 Campinas, SP - Brazil
Total Affiliations: 2
|
| Document type: | Journal article |
| Source: | ACS APPLIED NANO MATERIALS; v. 2, n. 9, p. 5460-5468, SEP 2019. |
| Web of Science Citations: | 0 |
| Abstract | |
Drug trafficking is a major worldwide problem. In this context, cocaine is one of the most commonly used drugs of abuse. In addition, street cocaine is commonly seized adulterated with pharmaceutical compounds, and the composition of the mixture provides a chemical fingerprint that can assist the police in tracking the distribution route of the drug; hence, the development of facile, cost-effective methods for determining the composition of street cocaine is an important objective. Herein we report a simple strategy for the fabrication of paper-based analytical devices (PADs) for the dual electrochemical and surface-enhanced Raman scattering (SERS) determination of cocaine samples. Accordingly, a 2-mu m-thick Au film was prepared by depositing gold nanoparticles (AuNPs) on office paper with wax-barrier templates to create nanostructured gold tracks that are mainly formed by Au(111) fcc planes as electrodes and SERS transducers. These devices were characterized by scanning electron microscopy, X-ray diffractometry, electrochemical impedance spectroscopy, and energy-dispersive X-ray spectroscopy. The optimized device is simple and inexpensive to prepare and exhibited a Raman-scattering enhancement factor of 3 X 10(6), a 15-fold superior electroactive area, and a 2.6-fold decrease in charge-transfer resistance when compared with a conventional Au electrode. In addition, these PADs were successfully used in a forensics scenario to screen and analyze a seized street cocaine sample, determine its chemical profile, and to identify simultaneously caffeine, paracetamol, and levamisole adulterants. (AU) | |
| FAPESP's process: | 16/21070-5 - Vibrational spectroscopy with spatial resolution |
| Grantee: | Mauro Carlos Costa Ribeiro |
| Support Opportunities: | Research Projects - Thematic Grants |
| 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: | 16/16477-9 - Fabrication of portable paper-based analytical devices with electrochemical and colorimetric detection system aiming at forensic, clinical, and environmental applications |
| Grantee: | William Reis de Araujo |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |