title: Shortcomings of protein removal prior to high performance liquid chromatographic analysis-A case study using method development for BAY 11-7082.
abstract: During the analytical method development for BAY 11-7082 ((E)-3-[4-methylphenylsulfonyl]-2-propenenitrile), using HPLC-MS-MS and HPLC-UV, we observed that the protein removal process (both ultrafiltration and precipitation method using organic solvents) prior to HPLC brought about a significant reduction in the concentration of this compound. The use of a structurally similar internal standard, BAY 11-7085 ((E)-3-[4-t-butylphenylsulfonyl]-2-propenenitrile), was not effective in compensating for the loss of analyte as the extent of reduction was different to that of the analyte. We present here a systematic investigation of this problem and a new validated method for the determination of BAY 11-7082.
authors.affiliation: School of Pharmacy, University of Queensland, Brisbane, Qld 4072, Australia. a.hewavitharana@pharmacy.uq.edu.au
authors.forename: A K
authors.initials: AK
authors.lastname: Hewavitharana
authors.forename: C
authors.initials: C
authors.lastname: Hyde
authors.forename: R
authors.initials: R
authors.lastname: Thomas
authors.forename: P N
authors.initials: PN
authors.lastname: Shaw
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D016328:NF-kappa B / Q000037:antagonists & inhibitors; D009570:Nitriles / Q000032:analysis*; D011506:Proteins / Q000302:isolation & purification*; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet; D013450:Sulfones / Q000032:analysis*
chemical_list: C434003:3-(4-methylphenylsulfonyl)-2-propenenitrile; D016328:NF-kappa B; D009570:Nitriles; D011506:Proteins; D013450:Sulfones