title: Quantification of Interactions between Serum Albumin and Endogenous Free Fatty Acids or Exogenous Chemicals by Stable Isotope-Coded Mass Spectrometry.
abstract: As primary endogenous ligands of serum albumin, free fatty acids exert versatile effects on the albumin conformation through cooperative or competitive interactions with exogenous chemicals. Based on equilibrium partition between n-hexane and aqueous phases, we have established three indexes, defined as R A, R V, and R T, for quantitative assessment of the intrinsic binding affinity, the affinitive variation induced by exogenous chemicals, and the topological dependence of albumin affinity, respectively. When albumin molecules in the aqueous phase are in native or denatured forms, or disturbed by exogenous chemicals, corresponding changes of free fatty acids in the n-hexane phase can be quantified by an iFFAM (isotope-coded free fatty acid methylation) approach. Free fatty acids from the control and the sample are differentially derived by d0- or d3-methanol and analyzed by gas chromatography-mass spectrometry. Changes of fatty acids can be revealed by peak ratios of d0- or d3-labeled fragment ions of fatty acid methyl esters.
authors.affiliation: Key Laboratory of Pesticides and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University , Wuhan, Hubei 430079, P. R. China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Li
authors.affiliation: Key Laboratory of Pesticides and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University , Wuhan, Hubei 430079, P. R. China.
authors.forename: Yingxia
authors.initials: Y
authors.lastname: Yue
authors.affiliation: Key Laboratory of Pesticides and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University , Wuhan, Hubei 430079, P. R. China.
authors.forename: Jianjian
authors.initials: J
authors.lastname: Li
authors.affiliation: Key Laboratory of Pesticides and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University , Wuhan, Hubei 430079, P. R. China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Wang
authors.affiliation: Key Laboratory of Pesticides and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University , Wuhan, Hubei 430079, P. R. China.
authors.forename: Jieying
authors.initials: J
authors.lastname: Fu
authors.affiliation: Key Laboratory of Pesticides and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University , Wuhan, Hubei 430079, P. R. China.
authors.forename: Hongying
authors.initials: H
authors.lastname: Zhong
keywords: Mass spectrometry; exogenous chemicals; free fatty acids; interactions; serum albumin