Influence of the Buffer Organic Cation on the Chiral Separation of Some Basic Drugs by Capillary Zone Electrophoresis

Abstract

This paper addresses the influence of small organic cations in the background electrolyte (BGE) on chiral separation by capillary zone electrophoresis (CZE). Seven basic drugs, viz. alprenolol, amphetamine, anisodamine, isoprenaline, pinacidil, synephrine, and verapamil were used as test compounds with hydroxylpropyl‐β‐cyclodextrin (HP‐β‐CD) as the chiral selector. Resolution of the chiral test compounds was studied at pH 2.5 in the presence of Tris, ethanolamine, diethanolamine, triethanolamine, diethylamine, and triethylamine, which exist in their cationic forms at this pH value. Among the six cationic additives studied, triethylamine is most effective in enhancing resolution. A tentative mechanism of the effect is proposed.

Separation and determination of norepinephrine, epinephrine and isoprinaline enantiomers by capillary electrophoresis in pharmaceutical formulation and human serum

“…The validation of this method for the quantitation of isoprenaline aerosol and to the analysis of serum samples spiked norepinephrine and epinephrine was performed. Compared with the previous methods [10][11][12][13][14][15][16][17][18], the merit of this work was used to analyze enantiomers of norepinephrine, epinephrine or isoprinaline in pharmaceutical formulation and human serum. The results indicated the proposed method represents good selectivity, precision and accuracy.…”

“…A number of analytical methods have been reported to determine EP, NE and isoprenaline (IP) enantiomers [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Among them, high-performance liquid chromatography (HPLC) and capillary electrophoresis (CE) are the most widely used separation techniques.…”

“…Male and Luong [13] demonstrated DM-␤-CD as chiral selector to separate NE, EP and IP, but the separation of NE and EP could not be improved. Dong and Sun [14] and Liu and Nussbaum [15], respectively, reported baseline separation of IP by using HP-␤-CD, or DM-␤-CD, CM-␤-CD as chiral selector. Garcia-Ruiz and Marina [16] and Cucinotta et al [17] studied the enantiomer separation of NE and EP by using permethylated-␤-CD or 6-O-succinil-␤-CD as chiral selector, however, the tested of NE and EP enantiomers could not be completely resolved.…”

Diastereomeric and enantiomeric high-performance liquid chromatographic separation of synthetic anisodamine

“…Thus, there is a clear need for method able to obtain two racemates (I and II) and analytical methods by which enantioseparation of 654-2, I and II can be realized. Although certain capillary electrophoresis (CE) methods with high resolution capability and short analysis time have been established for the enantioseparation of 654-2 [5,6,[13][14][15], no HPLC method, one of the most widely used techniques for the enantioselective analysis of chiral drugs [16], has been reported for the enantioseparation of 654-2. In this paper, we report the preparative diastereo-separation of I and II from 654-2 by the reverse phase HPLC and the direct enantioseparation of 654-2, I and II on HPLC with CHIRALPAK AD-H. Our chiral HPLC method with the possibility to transfer to preparative scale provides an alternative for the separation of four stereoisomers of 654-2.…”

Chiral separation of nanomole amounts of alprenolol with cITP/NMR

“…The enantiomeric separation of alprenolol has been reported with a mixture of native cyclodextrins (CD) and sodium dodecyl sulfate (SDS) at pH 9.3 [36]. In addition, modified cyclodextrins are used frequently to separate alprenolol and other β-blockers [37,38]. These more expensive modified cyclodextrins allow the separation of a broad range of chiral molecules.…”