title: Determination of the enantiomers of salbutamol and its 4-O-sulphate metabolites in biological matrices by chiral liquid chromatography tandem mass spectrometry.
abstract: Sensitive, mass spectrometry based bioanalytical methods are described for the determination of the R- and S-enantiomers of the beta-agonist salbutamol (albuterol) and its 4-O-sulphate metabolite in human plasma and urine. In both methods samples are prepared by 96 well format solid phase extraction using a custom built robotic system. Extracts are then analysed by liquid chromatography tandem mass spectrometry (LC-MS/MS) using a teicoplanin-based chiral stationary phase and selected reaction monitoring. The methods are accurate (bias < +/- 10%), precise (%CV < 11%) and sensitive, providing lower limits of quantitation (LLoQ) in plasma of 100 pg/mL and 5 ng/mL for the enantiomers of salbutamol and its 4-O-sulphate metabolite, respectively. By restricting the chiral method for plasma to the enantiomers of salbutamol only, it was possible to revalidate at an improved LLoQ of 25 pg/mL. A high throughout LC-MS/MS method has also been developed for racemic salbutamol only, which uses a similar extraction procedure but a conventional C8 column. The method has a reduced analysis time of three minutes per sample and using a high sensitivity, triple quadrupole mass spectrometer provides an LLoQ of 5 pg/mL based on extraction of 0.5 mL of plasma.
authors.affiliation: Department of International Bioanalysis, Glaxo Wellcome R & D, Hertfordshire, UK.
authors.forename: K B
authors.initials: KB
authors.lastname: Joyce
authors.forename: A E
authors.initials: AE
authors.lastname: Jones
authors.forename: R J
authors.initials: RJ
authors.lastname: Scott
authors.forename: R A
authors.initials: RA
authors.lastname: Biddlecombe
authors.forename: S
authors.initials: S
authors.lastname: Pleasance
mesh_terms: D000318:Adrenergic beta-Agonists / Q000032:analysis* / Q000097:blood / Q000493:pharmacokinetics; D000420:Albuterol / Q000032:analysis* / Q000097:blood / Q000493:pharmacokinetics; D002853:Chromatography, Liquid; D006801:Humans; D007202:Indicators and Reagents; D013058:Mass Spectrometry; D011786:Quality Control; D013237:Stereoisomerism; D013431:Sulfates / Q000032:analysis / Q000097:blood
chemical_list: D000318:Adrenergic beta-Agonists; D007202:Indicators and Reagents; D013431:Sulfates; D000420:Albuterol