title: Analytical and semi-preparative high-performance liquid chromatographic separation and assay of hydroxychloroquine enantiomers.
abstract: (+/-)-Hydroxychloroquine (HCQ) is an antimalarial and anti-arthritic drug which is administered as the racemate. An accurate, precise and sensitive high-performance liquid chromatographic assay was developed for the determination of HCQ enantiomers in samples from human plasma, serum, whole blood, and urine. After addition of (+/-)-chloroquine (internal standard), samples of blood component (0.5 ml) or urine (0.1 ml) were alkalinized and extracted with 5 ml of diethyl ether. After solvent evaporation the residues were derivatized with (+)-di-O-acetyl-L-tartaric anhydride at 45 degrees C for 30 min. The resulting diastereomers were then resolved using a C8 analytical column with a mobile phase consisting of 0.05 M KH2PO4 (pH 3)-methanol-ethanol-triethylamine (78:22:1:0.08). The ultraviolet detection wavelength was set at 343 nm. The derivatized HCQ enantiomers eluted in less than 40 min, free of interfering peaks. Excellent linear relationships (r2 > 0.997) were obtained between the area ratios and the corresponding plasma concentrations over a range of 12.5-500 ng/ml. The diastereomers could be hydrolysed using microwave energy and neutral pH, which enabled us to resolve the enantiomers on a semi-preparative (C18 column) scale. The method was suitable for the analysis and semi-preparative separation of HCQ enantiomers.
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Canada.
authors.forename: D R
authors.initials: DR
authors.lastname: Brocks
authors.forename: F M
authors.initials: FM
authors.lastname: Pasutto
authors.forename: F
authors.initials: F
authors.lastname: Jamali
mesh_terms: D000328:Adult; D000812:Anhydrides; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D006886:Hydroxychloroquine / Q000097:blood / Q000378:metabolism* / Q000652:urine; D008297:Male; D015203:Reproducibility of Results; D013237:Stereoisomerism; D013644:Tartrates
chemical_list: D000812:Anhydrides; D013644:Tartrates; D006886:Hydroxychloroquine; C059721:O,O-diacetyl tartaric acid anhydride