Portal de Periódicos da CAPES

Artigo Produção Nacional Revisado por pares

BIBTEX RIS

Rapid separation of post‐blast explosive residues on glass electrophoresis microchips

2018; Wiley; Volume: 40; Issue: 3 Linguagem: Inglês

10.1002/elps.201800245

1522-2683

Kemilly M.P. Pinheiro, Roger Cardoso Moreira, Kariolanda C.A. Rezende, Márcio Talhavini, Lúcio Paulo Lima Logrado, José Augusto Fragale Baio, Marcos R.V. Lanza, Wendell K. T. Coltro,

Advanced Chemical Sensor Technologies

Abstract This study describes the development of an analytical methodology based on the use of microchip electrophoresis (ME) devices integrated with capacitively coupled contactless conductivity detection (C 4 D) for the separation and detection of inorganic anions in post‐blast explosive residues. The best separation condition was achieved using a running buffer composed of 35 mmol/L lactic acid, 10 mmol/L histidine and 0.070 mmol/L cetyl(trimethyl ammonium) bromide. For C 4 D measurements, the highest sensitivity was obtained applying a 700 kHz sinusoidal wave with excitation voltage of 20 V pp . The separation of Cl − , NO 3 − , NO 2 − , SO 4 2− , ClO 4 − and ClO 3 − was performed within ca . 150 s with baseline resolution and efficiencies between 4.4 × 10 4 and 1.7 × 10 5 plates/m. The found limits of detection ranged between 2.5 and 9.5 μmol/L. Last, real samples of post‐blast explosive residues were analyzed on the ME‐C 4 D devices obtaining successfully the determination of Cl − , NO 3 − and SO 4 2− . The achieved concentration values varied between 12.8–72.5 mg/L for Cl − , 1.7–293.1 mg/L for NO 3 − and 1.3–201.3 mg/L for SO 4 2− . The data obtained using ME‐C 4 D devices were in good agreement with the concentrations found by ion chromatography. The approach reported herein has provided short analysis time, instrumental simplicity, good analytical performance and low cost. Furthermore, the ME‐C 4 D devices emerge as a powerful and portable analytical platform for on‐site analysis demonstrating to be a promising tool for the crime scene investigation.