title: Ambient analysis of leachable compounds from single-use bioreactors with desorption electrospray ionization time-of-flight mass spectrometry.
abstract: BACKGROUND
  Trace levels of bis(2,4-di-tert-butylphenyl)phosphate (BdtbPP) leaching from single-use bioreactors (SUBs) were recently found to be highly detrimental to mammalian cell growth. The traditional approach to detect the leachable requires time-consuming solvent extraction of SUBs. To assist the qualification of SUBs and/or their manufacturing raw materials in biopharmaceutical development and manufacturing, it is essential to develop a rapid and sensitive analytical approach for detecting this leachable and related compounds, which is described in this study.
  
  
  METHODS
  Native films from several commercially available SUBs were directly examined by desorption electrospray ionization (DESI) time-of-flight mass spectrometry (TOFMS) without sample preparation. As a comparison, the same SUBs were also analyzed by high-performance liquid chromatography (HPLC)/ultraviolet (UV) following the solvent extraction.
  
  
  RESULTS
  With a suitable spray solvent selected in this study, DESI-TOFMS enabled rapid and sensitive detection of leachable compounds directly from SUBs. Accurate mass measurement from TOFMS allowed ready identification of BdtbPP, its parent analog compound, and other polymer components in the SUBs from their protonated surrogates. The relative abundances of BdtbPP in different SUBs measured by DESI-TOFMS exhibited good correlation with those from the traditional extraction-based approach with HPLC/UV.
  
  
  CONCLUSIONS
  A rapid and sensitive approach was developed for direct detection of BdtbPP and other leachables from SUBs using DESI-TOFMS. The results are in high accordance with those from conventional approaches, which indicates the usefulness of the proposed method as a qualification tool for SUBs in biopharmaceutical development and also its great potential in the analysis of extractables/leachables in a wide variety of materials, process components, devices and containers used in the pharmaceutical industry.
authors.affiliation: Drug Product Development, Amgen Inc., One Amgen Center Drive, Thousand Oaks, CA, 91320, USA.
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Kennedy
authors.forename: Michael
authors.initials: M
authors.lastname: Ronk
authors.forename: Liliana
authors.initials: L
authors.lastname: Marghitoiu
authors.forename: Hans
authors.initials: H
authors.lastname: Lee
authors.forename: Yasser
authors.initials: Y
authors.lastname: Nashed-Samuel
mesh_terms: D019149:Bioreactors; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004864:Equipment and Supplies; D010755:Organophosphates / Q000032:analysis* / Q000737:chemistry; D010968:Plasticizers; D012997:Solvents / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013499:Surface Properties
chemical_list: D010755:Organophosphates; D010968:Plasticizers; D012997:Solvents