Premium
Online sample concentration and analysis of drugs of abuse in human urine by micelle to solvent stacking in capillary zone electrophoresis
Author(s) -
Aturki Zeineb,
Fanali Salvatore,
Rocco Anna
Publication year - 2016
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.201600312
Subject(s) - chromatography , capillary electrophoresis , chemistry , analyte , stacking , solvent , micelle , urine , capillary action , quantitative analysis (chemistry) , matrix (chemical analysis) , analytical chemistry (journal) , materials science , aqueous solution , biochemistry , organic chemistry , composite material
A sensitive and rapid CZE‐UV method was developed to determine drugs and their metabolites’ presence in human urine. Ten drugs of abuse were analyzed including four amphetamines, cocaine, cocaethylene, heroin, morphine, 6‐monoacetylmorphine, and 4‐methylmethcathinone. An MSS (micelle to solvent stacking) approach was evaluated to enhance method sensitivity. This method considers composition of the micellar sample solution matrix and the injection time. Several analytical conditions influencing the resolution of the drugs mixture as pH and buffer concentration, organic solvent content, were also investigated. The base‐line separation of all studied analytes in the same run was achieved within 18 min in an uncoated fused silica capillary (50 μm id × 60 cm) using a background solution containing 50 mM phosphate buffer pH 2.5 and 30% ACN v/v. Other experimental parameters such as applied voltage and capillary temperature were set up at 20 kV and 20°C, respectively. LOD values ranging between 15 and 75 ng/mL for all studied compounds were obtained. From a comparison with conventional CZE, the proposed method provides an increase of sensitivity (39‐ to 55‐fold enhancement factor). Under optimal MSS‐CZE conditions, good linearity was achieved ( R 2 ≤ 0.9998). The method was finally applied to the analysis of urine samples spiked with a standard mixture after a sample pretreatment, reaching satisfactory recovery values.