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Author Spotlight: Optimizing Apoplast Protein Extraction for Efficient Recovery of Recombinant Proteins from Plant Cells
Published on: July 5, 2024
Direct Analysis of Underivatized Amino Acids in Plant Extracts by LC-MS/MS (Improved Method)
Björn Thiele1,2, Michelle Hupert3, Beatrix Santiago-Schübel3
1Institute of Bio- and Geosciences, IBG-2: Plant Sciences, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany. b.thiele@fz-juelich.de.
Abstract:
In this chapter we describe a method for quantification of 20 proteinogenic amino acids by liquid chromatography-mass spectrometry which affords neither derivatization nor the use of organic solvents. Analysis of the underivatized amino acids is performed by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) in the positive ESI mode. Separation is achieved on a strong cation exchange (SCX) column (Luna 5 μ SCX 100 Å) with 5% acetic acid in water (A) and 75 mM ammonium acetate in water (B). Quantification is accomplished by use of d2-phenylalanine as internal standard achieving limits of detection of 5-50 nM. The method was successfully applied for the determination of proteinogenic amino acids in plant extracts.
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