Simultaneous separation on a bisphenylureido β-cyclodextrin column and determination of eight antihistamine enantiomers in human plasma by HPLC

A bis (3,5-dichlorophenylureido)-β-cyclodextrin stationary phase (CUCDP) was prepared and characterized. It had strong chiral separation abilities for antihistamines ( R s = 1.61–2.58) in isocratic elution, including chlorpheniramine maleate, bromopheniramine maleate, promethazine hydrochloride and trimeprazine tartrate. Based on CUCDP, a new HPLC method for simultaneous separation and determination of the above eight antihistamine enantiomers ( R s = 1.58–1.92) in human plasma by gradient elution was established. The optimized conditions were as follows: a simple sample pretreatment with acetonitrile (ACN) to precipitate protein, a gradient elution of 0.5 % triethylammonium acetate (TEAA, pH = 4.0)-ACN as the mobile phase at a flow rate of 0.5 mL/min, column temperature at 20 °C, a photo-diode array detector (PDA) at 260 nm, and the sampling volume of 10 μL. The good linear relationships for all enantiomers were observed in the concetration range of 0.25–10.0 μg/mL ( R 2  = 0.9986–0.9993). The average recoveries were 84.80 %–103.30 % with the RSDs of 1.24 %–2.26 % ( n  = 5). The limits of detection (LODs) and limits of quantification (LOQs) were 0.015–0.05 μg/mL and 0.05–0.15 μg/mL, respectively. At present, the reported cyclodextrin-based CSPs had not such separation ability for antihistamines by HPLC. However, the new CUCDP exhibited high chiral selectivity for antihistamines, which was mainly related to the introduction of bis phenylureido group into the rim of cyclodextrin, and the strengthening of hydrogen bonding, π–π stacking and inclusion between CUCDP and analytes. This method could save analysis time, reduce solvent consumption, and improve efficiency at low cost.