Simultaneous Quantitative Determination of Synthetic Cathinone Enantiomers in Urine and Plasma Using GC-NCI-MS

Abstract

Development and validation of sensitive and selective method for enantioseparation and quantitation of synthetic cathinones is reported using GC-MS triple quadrupole mass spectrometry with negative chemical ionization (NCI) mode. Indirect chiral separation of thirty-six synthetic cathinone compounds has been achieved by using an optically pure chiral derivatizing agent (CDA) called (S)-(−)-N-(trifluoroacetyl)pyrrolidine-2-carbonyl chloride (L-TPC), which converts cathinone enantiomers into diastereoisomers that can be separated on achiral columns. As a result of using Ultra Inert 60 m column and performing slow heating rate (2°C/min) on the GC oven, an observed enhancement in enantiomer peak resolution has been achieved. An internal standard, (+)-cathinone, was used for quantitation of synthetic cathinones. Method validation in terms of linearities and sensitivity in terms of limits of detection (LODs), limits of quantitation (LOQs), recoveries, and reproducibilities has been obtained for fourteen selected compounds that examined simultaneously as a mixture after being spiked in urine and plasma. It was found that the LOD of the fourteen synthetic cathinones in urine was in the range of 0.26–0.76 µg/L, and in plasma, it was in the range of 0.26–0.34 µg/L. While the LOQ of the mixture in urine was in the range of 0.86–2.34 µg/L, and in plasma, it was in the range of 0.89–1.12 µg/L. Unlike the electron impact (EI) ion source, NCI showed better sensitivity by two orders of magnitude by comparing the obtained results with the recently published reports for quantitative analysis and enantioseparation of synthetic cathinones.

Chiral separation of cathinone derivatives using β‐cyclodextrin‐assisted capillary electrophoresis–Comparison of four different β‐cyclodextrin derivatives used as chiral selectors

“…In literature, several articles deal with the enantioseparation of cathinone related compounds and further NPS. Chiral separations were carried out via different separation techniques including HPLC , supercritical fluid chromatography , GC , and also CE and CEC . Electrophoretically driven methods have great advantage that no expensive chiral stationary phases are needed.…”

Synthetic Cathinones: Recent Developments, Enantioselectivity Studies and Enantioseparation Methods

“…As shown in Table 1 , recently, Alremeithi et al [ 108 ] developed a highly sensitive and selective method for the separation of 14 cathinone derivatives in urine and plasma samples using GC-MS and L-TPC as a derivatization agent. Meetani et al [ 113 ] were able to detect and quantify, for the first time, the enantiomers of 18 synthetic cathinones with tertiary amine structures in urine and plasma samples using a direct HPLC-UV method with amylose-based and cellulose-based CSPs.…”

Enantiodetermination of R,S-3,4-methylenedioxypyrovalerone in urine samples by high pressure in-line solid-phase extraction capillary electrophoresis-mass spectrometry

“…This increase is mainly due to the similar euphoric effects of these cathinones, but lower prices and easier acquisition than amphetamines [1][2][3]. For this reason, the interest of the police and health authorities in the detection and determination of these substances has grown, as it is reflected in the emergence of extensive literature related to their analysis [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18].…”