Citation

Rocha DS, Duarte LC, Silva-Neto HA, Chagas CLS, Santana MHP, Antoniosi Filho NR, Coltro WKT. Talanta 2021; 232: 122408.

Copyright

(Copyright © 2021, Elsevier Publishing)

DOI

10.1016/j.talanta.2021.122408

PMID

unavailable

Abstract

This study describes the development of a new electrochemical paper-based analytical device (ePAD) on alumina sandpaper substrate through a pencil-drawing process for square wave voltammetry measurements of midazolam maleate used as a "date rape drug" in beverages. The proposed ePAD was assembled on a reusable 3D printed holder to delimit its geometric area and ensure better robustness. The ePAD was characterized by scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy and Raman spectroscopy. The direct drawing of ePADs on sandpaper platforms through a graphite pencil has offered suitable repeatability (RSD = 1.0%) and reproducibility (RSD = 4.0%) using [Fe(CN)(6)](4-) as redox probe. The proposed ePAD provided linear behaviour in the midazolam maleate concentration range between 2.5 and 150 mg L(-1) and a limit of detection of 2.0 mg L(-1). The feasibility of the ePAD for forensic application was successfully demonstrated through the detection of midazolam in different beverages (water, beer, liquor, and vodka). The intended application revealed low interference of other compounds present in beverages. Based on the achieved results, the proposed ePAD has offered great accuracy with no statistical difference at 95% confidence level from the data recorded by high performance liquid chromatography. The operational simplicity and the robustness ensured by the assembling on a reusable 3D printed holder make the ePAD drawn on sandpaper platform a powerful and promising analytical tool for the analysis of "date rape drugs" opening new possibilities for on-site forensic investigations.

Language: en

Keywords

3D printing; Electrochemical sensors; Forensic chemistry; Paper-based sensors; Pulse voltammetry