title: Combination of poly(diallyldimethylammonium chloride) and hydroxypropyl-γ-cyclodextrin for high-speed enantioseparation of phenothiazines by capillary electrophoresis.
abstract: High-speed capillary electrophoresis (CE) enables the simple, rapid, and inexpensive analysis of large sets of chiral samples in the pharmaceutical industry. Hence, we developed a novel method for separating enantiomers of d,L-phenothiazines simply and rapidly, based on using poly(diallyldimethylammonium chloride) (PDDAC) as an additive and hydroxypropyl-γ-cyclodextrin (Hp-γ-CD) as a chiral selector in capillary electrophoresis. Adding 0.9% PDDAC to the background electrolyte generated a stable, high, and reversed electroosmotic flow (EOF). Hp-γ-CD not only worked as a complexing agent to increase the chiral resolution between d,L-phenothiazines but also decreased the effective electrophoretic mobility of these drugs. Combining PDDAC and Hp-γ-CD as buffer additives enabled CE to achieve a high-speed enantioseparation of five pairs of d,L-phenothiazines. A decrease in capillary length and an increase in the intensity of the electric field further shortened the separation time. When the background electrolyte contained 0.9% PDDAC, 5mM Hp-γ-CD, and 75 mM formic acid (pH 3.0), enantioseparation of the d,L-phenothiazines was attained within 230 s by applying a capillary length of 32.5 cm and an electric field of 292 V cm(-1). The limit of detection (LOD) of the d,L-phenothiazines at a signal-to-noise ratio of 3 ranged from 2 to 8 μM. We demonstrated the feasibility of this method by detecting the five pairs of d,L-phenothiazines in urine samples.
authors.affiliation: Department of Chemistry, National Kaohsiung Normal University, Kaohsiung City, Taiwan, ROC.
authors.forename: Po-Lin
authors.initials: PL
authors.lastname: Yu
authors.affiliation: Department of Chemistry, National Kaohsiung Normal University, Kaohsiung City, Taiwan, ROC.
authors.forename: Yi-Yi
authors.initials: YY
authors.lastname: Tu
authors.affiliation: Department of Chemistry, National Kaohsiung Normal University, Kaohsiung City, Taiwan, ROC. Electronic address: t3644@nknucc.nknu.edu.tw.
authors.forename: Ming-Mu
authors.initials: MM
authors.lastname: Hsieh
mesh_terms: D019075:Electrophoresis, Capillary / Q000379:methods*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010640:Phenothiazines / Q000302:isolation & purification* / Q000652:urine*; D011095:Polyethylenes / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D059629:Signal-To-Noise Ratio; D013237:Stereoisomerism; D016482:Urinalysis / Q000379:methods*; D047408:gamma-Cyclodextrins / Q000737:chemistry*
chemical_list: D010640:Phenothiazines; D011095:Polyethylenes; D000644:Quaternary Ammonium Compounds; D047408:gamma-Cyclodextrins; C479659:hydroxypropyl-gamma-cyclodextrin; C041004:poly-N,N-dimethyl-N,N-diallylammonium chloride; C031637:phenothiazine
keywords: Capillary electrophoresis; Chiral separation; Cyclodextrins; Phenothiazines; Poly(diallyldimethylammonium chloride)