title: Application of a rapid and selective method for the simultaneous determination of carebastine and pseudoephedrine in human plasma by liquid chromatography-electrospray mass spectrometry for bioequivalence study in Korean subjects.
abstract: We describe a simple, rapid and sensitive high-performance liquid chromatography-electrospray ionization tandem mass spectrometric method that was developed for the simultaneous determination of carebastine and pseudoephedrine in human plasma using cisapride as an internal standard. Acquisition was performed in multiple-reaction monitoring mode by monitoring the transitions: m/z 500.43 > 167.09 for carebastine and m/z 166.04 > 147.88 for pseudoephedrine. The devised method involves a simple single-step liquid-liquid extraction with ethyl acetate. Chromatographic separation was performed on a C(18) reversed-phase chromatographic column at 0.2  mL/min by isocratic elution with 10  mM ammonium formate buffer-acetonitrile (30:70, v/v; adjusted to pH 3.3 with formic acid). The devised method was validated over 0.5-100  ng/mL of carebastine and 5-1000  ng/mL of pseudoephedrine with acceptable accuracy and precision, and was successfully applied to a bioequivalence study involving a single oral dose (10  mg of ebastine plus 120  mg of pseudoephedrine complex) to healthy Korean volunteers.
authors.affiliation: College of Pharmacy, Kyung Hee University, Hoegi-Dong, Dongdaemun-Gu, Seoul 130-701, Republic of Korea.
authors.forename: Myung-Jae
authors.initials: MJ
authors.lastname: Lee
authors.forename: Heon-Woo
authors.initials: HW
authors.lastname: Lee
authors.forename: Jong-Min
authors.initials: JM
authors.lastname: Kang
authors.forename: Ji-Hyung
authors.initials: JH
authors.lastname: Seo
authors.forename: Seong-Kun
authors.initials: SK
authors.lastname: Tak
authors.forename: Wangseob
authors.initials: W
authors.lastname: Shim
authors.forename: Sung-Vin
authors.initials: SV
authors.lastname: Yim
authors.forename: Seung Jae
authors.initials: SJ
authors.lastname: Hong
authors.forename: Kyung-Tae
authors.initials: KT
authors.lastname: Lee
mesh_terms: D002090:Butyrophenones / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D020117:Cisapride / Q000032:analysis / Q000737:chemistry; D018592:Cross-Over Studies; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D010880:Piperidines / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics; D054199:Pseudoephedrine / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D056910:Republic of Korea; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013810:Therapeutic Equivalency; D055815:Young Adult
chemical_list: D002090:Butyrophenones; D010880:Piperidines; C058251:carebastine; D054199:Pseudoephedrine; D020117:Cisapride