title: Direct determination of pindolol enantiomers in human serum by column-switching LC-MS/MS using a phenylcarbamate-beta-cyclodextrin chiral column.
abstract: A direct analytical method of pindolol enantiomers in body fluids was developed by means of column-switching semi-microcolumn liquid chromatography/tandem mass spectrometry (LC-MS/MS). A pre-column packed with a silica-based cation-exchanger was used for on-line sample cleanup. Subsequent enantioseparation was conducted with a phenylcarbamate-beta-cyclodextrin (ph-beta-CD) bonded semi-micro chiral column (2.0 mm inner diameter (i.d.)). A 25-microl aliquot of serum/urine samples was directly injected into the system after simple filtration with a membrane filter. Separated enantiomers were monitored with positive electrospray ionization (ESI) and selected reaction monitoring (SRM). R(+)- and S(-)-pindolol in serum and urine were determined separately within 16 min at a resolution factor of 1.9. The detection limits at a signal-to-noise (S/N) ratio of 5 were 0.13 ng ml(-1) for both enantiomers. The linearity of the method was in the range of 0.25-100 ng ml(-1) with regression coefficient greater than 0.997. Recoveries from spiked serum and urine samples, estimated by the external standard method, were between 94.8 and 117.6% with a relative standard deviation (RSD) ranging from 2.1 to 18%.
authors.affiliation: Pharmaceutical Research Center, Shiseido Co., Ltd., 2-12-1 Fukuura, Kanazawa-ku, Yokohama-shi, Japan. akira.motoyama@to.shiseido.co.jp
authors.forename: Akira
authors.initials: A
authors.lastname: Motoyama
authors.forename: Ayako
authors.initials: A
authors.lastname: Suzuki
authors.forename: Osamu
authors.initials: O
authors.lastname: Shirota
authors.forename: Ryujiro
authors.initials: R
authors.lastname: Namba
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000097:blood / Q000652:urine; D002219:Carbamates / Q000737:chemistry*; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods; D003505:Cyclodextrins / Q000737:chemistry*; D006801:Humans; D010869:Pindolol / Q000097:blood* / Q000652:urine*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods; D013237:Stereoisomerism; D047392:beta-Cyclodextrins
chemical_list: D000319:Adrenergic beta-Antagonists; D002219:Carbamates; D003505:Cyclodextrins; D047392:beta-Cyclodextrins; D010869:Pindolol; C031215:betadex; C059692:phenylcarbamic acid