Enantiomeric separation of amphetamine and related compounds by liquid chromatography using precolumn derivatization witho-phthaldialdehyde

Abstract

The utility of the derivatization reagent o-phthaJdiaJdehyde (OPA) in combination with the chiral thiol N-acetyI-L-cysteine (NAC) for the enantioselective analysis of primary amphetamines and structurally related substances has been investigated. The diastereomers obtained have been chromatographed on an achiral, reversed phase Cl8 column (125 mm x 4 mm i.d., 51~m), and detected fluorimetrically The influence of parameters affecting the chromatographic separation aswell as the derivatization reaction has been optimized, using amphetamine, norephedrine, norepinephrine and 3,4-methylenedioxyamphetamine (MDA) as model compounds. On the basis of the results obtained, possible conditions for the enantiomeric analysis of these substances are described. The selected conditions have been used successfully for the enantioselective quantitation of the compounds tested within 0.5 -10.0 I~g mL 1 concentration interval (each enantiomer), the limits of detection being 25 -50 ng mL 1. Examples of application to biological samples are also given.

Effect of the eluent on enantiomer separation of controlled drugs by liquid chromatography–ultraviolet absorbance detection–electrospray ionisation tandem mass spectrometry using vancomycin and native β-cyclodextrin chiral stationary phases

“…Direct enantioseparation of phenethylamines with LC has been obtained with various CSPs: chiral crown ether [20,21], cyclodextrin or its derivatives [6,[22][23][24][25][26], protein [25] and immunoaffinity [27] columns have been used. Indirect LC methods have also been of interest [3][4][5], but they suffer from inconveniences such as impure reagents and the fact that they are more time consuming.…”

“…The methods have been widely applied to enantiomeric separation of methamphetamine and related drugs [3][4][5][6][7][8][9][10][11][12]. The main chiral selector used in CE for phenethylamines has been native or modified ␤-cyclodextrin (␤-CD) [8][9][10][11], but also other cyclodextrins [12][13][14] and, e.g.…”

Enantiomeric separations of illicit drugs and controlled substances using cyclofructan‐based (LARIHC) and cyclobond I 2000 RSP HPLC chiral stationary phases

“…There have been reports on a variety of analytical methodologies for separating enantiomers of illicit drugs and controlled substances, including gas chromatography (GC), high performance liquid chromatography (HPLC), capillary electrophoresis (CE), GC‐MS, LC‐MS, and CE‐ESI‐MS . One approach may be superior to another depending on the goal of the investigator and the nature of the problems to be solved.…”

“…However in the case of physiological and biological studies on extremely small amounts of analyte, sensitivity and isolation from a complex biological matrix is problematic. Often, a prederivatization step is necessary in order to reach sufficiently low limits of detection in both GC and HPLC techniques …”

“…There have been reports on a variety of analytical methodologies for separating enantiomers of illicit drugs and controlled substances, including gas chromatography (GC), [1,[19][20][21] high performance liquid chromatography (HPLC), [1,[22][23][24][25][26][27][28] capillary electrophoresis (CE), [14,29] GC-MS, [30][31][32] LC-MS, [33][34][35][36] and CE-ESI-MS. [37] One approach may be superior to another depending on the goal of the investigator and the nature of the problems to be solved. Clearly, one method may be useful for biological assays while another approach is better suited for forensic assays or quality control of pharmaceutical products.…”