title: Derivatization of bisphenol A and its analogues with pyridine-3-sulfonyl chloride: multivariate optimization and fragmentation patterns by liquid chromatography/Orbitrap mass spectrometry.
abstract: BACKGROUND
  Due to the growing restrictions on the use of bisphenol A (BPA), several other bisphenols are gaining importance as substitutes for BPA in a variety of applications. There is, therefore, a real need for selective and sensitive methods based on mass spectrometry which will allow the human exposure to these new bisphenols to be assessed.
  
  
  METHODS
  Derivatization of BPA and its substitutes with pyridine-3-sulfonyl chloride is used to enhance the detection capability of bisphenols by electrospray ionization mass spectrometry. A multivariate experimental design, Box-Behnken response surface, was used to evaluate the influence of the main variables potentially affecting the derivatization yield. Fragmentation patterns for all the derivatized bisphenols were acquired by high-resolution/accurate-mass Orbitrap mass spectrometry.
  
  
  RESULTS
  Temperature and pH were identified as the most important factors affecting the derivatization yield of bisphenols. Fragmentation of the protonated molecules produced abundant analyte-specific product ions. Most of the derivatized bisphenols showed significant improvements in their signal-to-noise ratios compared with the underivatized forms. The stability of these derivatives was demonstrated through several freeze/thaw cycles, short-term room temperature and long-term cold storage.
  
  
  CONCLUSIONS
  Derivatization of BPA and its structural analogues with pyridine-3-sulfonyl chloride is proposed as a specific, sensitive, high-throughput approach to their analysis by liquid chromatography coupled to electrospray ionization mass spectrometry.
authors.affiliation: European Commission, Directorate General Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440, Geel, Belgium.
authors.forename: Jorge
authors.initials: J
authors.lastname: Regueiro
authors.affiliation: European Commission, Directorate General Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440, Geel, Belgium.
authors.forename: Andreas
authors.initials: A
authors.lastname: Breidbach
authors.affiliation: European Commission, Directorate General Joint Research Centre, Institute for Reference Materials and Measurements, Retieseweg 111, B-2440, Geel, Belgium.
authors.forename: Thomas
authors.identifier: http://orcid.org/0000-0003-2017-3788
authors.initials: T
authors.lastname: Wenzl