Ionic‐liquid‐based dispersive liquid–liquid microextraction coupled with high‐performance liquid chromatography for the forensic determination of methamphetamine in human urine

Abstract

Determination of methamphetamine in forensic laboratories is a major issue due to its health and social harm. In this work, a simple, sensitive, and environmentally friendly method based on ionic liquid dispersive liquid-liquid microextraction combined with high-performance liquid chromatography was established for the analysis of methamphetamine in human urine. 1-Octyl-3-methylimidazolium hexafluorophosphate with the help of disperser solvent methanol was selected as the microextraction solvent in this process. Various parameters affecting the extraction efficiency of methamphetamine were investigated systemically, including extraction solvent and its volume, disperser solvent and its volume, sample pH, extraction temperature, and centrifugal time. Under the optimized conditions, a good linearity was obtained in the concentration range of 10-1000 ng/mL with determination coefficient >0.99. The limit of detection calculated at a signal-to-noise ratio of 3 was 1.7 ng/mL and the relative standard deviations for six replicate experiments at three different concentration levels of 100, 500, and 1000 ng/mL were 6.4, 4.5, and 4.7%, respectively. Meanwhile, up to 220-fold enrichment factor of methamphetamine and acceptable extraction recovery (>80.0%) could be achieved. Furthermore, this method has been successfully employed for the sensitive detection of a urine sample from a suspected drug abuser.

Application of Carbonic Nanosheets Based on Urea Precursors as Dispersive Solid Phase Extraction Adsorbent for Extraction of Methamphetamine from Urine Samples

“…A paper reported electro-enhanced single-drop microextraction (EE-SDME) coupled with gas chromatography for amphetamine and methamphetamine extraction from urine media (10). In another work, 1-Octyl-3-methylimidazolium hexafluorophosphate as an ionic liquid, along with methanol was used as microextraction solvent in ionic liquid-based DLLME (IL-DLLME) combined with high performance liquid chromatography ultra violet detector method for effective extraction of MET from urine (11). Moreover, head space developed solid phase micro extraction (SPME) gas chromatography mass spectrometry method was applied for amphetamines extraction from urine while the PDMS fiber was derivatized by exposing the fiber to trifluoroacetic anhydride after the extraction.…”

The Effects of Parameters on the Efficiency of DLLME in Extracting of PAHs from Vegetable Samples

“…In some studies, the high viscosity was due to the excess addition of salts [27]. The salt formed ionic bonding and decrease the diffusion coefficients of analytes [29]. The ionic bonding was strong and not easily to be broken.…”

Dispersive liquid–liquid microextraction as an effective preanalytical step for the determination of estradiol in human urine

“…DLLME is a relatively new sample pretreatment method introduced in 2006 by Rezaee et al [37]. Although it was primarily designed for extraction of various organic compounds from water samples, it has found wide acceptance also in the analysis of complex environmental, biological (urine, plasma) and food (milk) samples [38][39][40][41][42]. DLLME is based on the formation of ternary system consisting of the aqueous phase and mixture of two solvents [43].…”