title: Quantitation of underivatized free amino acids in mammalian cell culture media using matrix assisted laser desorption ionization time-of-flight mass spectrometry.
abstract: In this investigation, a quantitative matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOFMS) method was developed for the analysis of underivatized free amino acids in mammalian cell culture media. Calibration curves were developed for 12 amino acids over the linear range of 1-100 microM with coefficients of determination ranging from r2 = 0.9220 to r2 = 0.9973. An aerospray method was utilized for the sample deposition method, and the matrix, alpha-cyano-4-hydroxycinnamic acid, served as the internal standard. This assay was used to analyze bioreactor samples from five time points in the process. Concentrations determined through interpolation of the calibration curves were comparable to those obtained via reversed-phase HPLC based analysis with an average percent difference of 19.71%. Repeatability and intermediate precision studies were also performed, and the relative standard deviations ranged from 0.5943 to 21.41 and 3.157 to 18.97, respectively.
authors.affiliation: Department of Chemistry and Biochemistry, University of the Sciences in Philadelphia, Philadelphia, Pennsylvania 19104, USA. Jennifer_2_Dally@GSK.com
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Dally
authors.forename: Joselina
authors.initials: J
authors.lastname: Gorniak
authors.forename: Rita
authors.initials: R
authors.lastname: Bowie
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Bentzley
mesh_terms: D000596:Amino Acids / Q000032:analysis*; D003470:Culture Media / Q000032:analysis*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D000596:Amino Acids; D003470:Culture Media