title: Liquid chromatography/tandem mass spectrometry for simultaneous determination of undeclared corticosteroids in cosmetic creams.
abstract: BACKGROUND
  Undeclared corticosteroids in creams intended for frequent use might cause serious side-effects, especially in children. In order to prevent this or find the cause, it was essential to develop a method for quick detection and quantification of low levels of corticosteroids.
  
  
  METHODS
  Eleven corticosteroids were used in this study: prednisolone, methylprednisolone, prednisolone-21-acetate, fluocinolone acetonide, fluocinolone acetonide-21-acetate, hydrocortisone-21-acetate, dexamethasone, betamethasone, betamethasone dipropionate, clobetasol propionate and triamcinolone. Separation was achieved via liquid chromatography (LC), and mass spectrometric analysis was conducted by electrospray ionization triple-quadrupole mass spectrometry (MS/MS) in the multiple reaction monitoring mode using corticosterone as internal standard.
  
  
  RESULTS
  Good separation by using a gradient-elution LC/MS/MS method with run time of 25 min enabled the use of a segmented detection method and consecutive decrease in detection limits. The proposed method has been validated in the linearity range of 10-1000 ng/mL with coefficients of determination higher than 0.990. The method has shown to have very low limits of quantification (0.75-3 ng/mL) with satisfactory precision and accuracy for each of the corticosteroids.
  
  
  CONCLUSIONS
  An LC/MS/MS method for the rapid and simultaneous determination of low levels of eleven topical corticosteroids in creams was developed, optimized and validated. The proposed method can be used for testing of different products indicated for the treatment of atopic dermatitis, including "natural products", and "herbal creams" with "miraculous effects".
authors.affiliation: University of Belgrade-Faculty of Pharmacy, Department of Drug Analysis, Vojvode Stepe 450, Belgrade, Serbia.
authors.forename: Jelena B
authors.initials: JB
authors.lastname: Golubović
authors.affiliation: University of Belgrade-Faculty of Pharmacy, Department of Drug Analysis, Vojvode Stepe 450, Belgrade, Serbia.
authors.forename: Biljana M
authors.initials: BM
authors.lastname: Otašević
authors.affiliation: University of Belgrade-Faculty of Pharmacy, Department of Drug Analysis, Vojvode Stepe 450, Belgrade, Serbia.
authors.forename: Ana D
authors.initials: AD
authors.lastname: Protić
authors.affiliation: University of Belgrade-Faculty of Pharmacy, Department of Drug Analysis, Vojvode Stepe 450, Belgrade, Serbia.
authors.forename: Aleksandra M
authors.initials: AM
authors.lastname: Stanković
authors.affiliation: University of Belgrade-Faculty of Pharmacy, Department of Drug Analysis, Vojvode Stepe 450, Belgrade, Serbia.
authors.forename: Mira L
authors.initials: ML
authors.lastname: Zečević
mesh_terms: D000305:Adrenal Cortex Hormones / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D002853:Chromatography, Liquid / Q000379:methods*; D016014:Linear Models; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D063465:Skin Cream / Q000032:analysis / Q000737:chemistry*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000305:Adrenal Cortex Hormones