Enantioseparation of phenothiazines through capillary electrophoresis with solid phase extraction and polymer based stacking

W.-B. Tseng
M.-M. Hsieh
T.-C. Chiu
P.-L. Yu
S.-H. Chen

Abstract

This study developed a sensitive method involving capillary electrophoresis (CE) coupled with ultraviolet absorption for the simultaneous separation of chiral phenothiazine drugs at nanomolar concentration levels. The method consists of hydroxypropyl-γ-cyclodextrin (Hp-γ-CD) as a chiral selector and poly (diallyldimethylammonium chloride) (PDDAC)-based CE. Five pairs of D,L-phenothiazines were baseline separated using a background electrolyte containing 0.9% PDDAC, 5 mM Hp-γ-CD, and 100 mM tris(hydroxymethyl)aminomethane (Tris)-formate (pH 3.0). The five pairs were successfully stacked on the basis of the difference in viscosity between the PDDAC-containing background electrolyte and the sample solution, with almost no loss of resolution. The combination of a solid-phase extraction and PDDAC-mediated CE can efficiently improve the sensitivity of the phenothiazine enantiomers. Under optimal conditions, calibration graphs displayed the linear range between 6 and 1500 nM, with relative standard deviation values lower than 3.5% (n = 5). Detection limit ranged from 2.1 to 6.3 nM for target analytes, and 607- to 1555-fold enhancement was achieved. The practicality of using the proposed method to determine five pairs of D,L-phenothiazines in urine is also validated, in which recoveries between recoveries of all phenothiazines from urine ranged from 89% to 101%. © 2018

Abstract Image

ScienceDirect Link

10.1016/j.jfda.2017.12.002

Recommended Citation

Tseng, W.-B.; Hsieh, M.-M.; Chiu, T.-C.; Yu, P.-L.; and Chen, S.-H. (2018) "Enantioseparation of phenothiazines through capillary electrophoresis with solid phase extraction and polymer based stacking," Journal of Food and Drug Analysis: Vol. 26 : Iss. 3 , Article 23.
Available at: https://doi.org/10.1016/j.jfda.2017.12.002

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