Mass Spectrometry of Biopolymers
CS

Analysis of protein intact mass

Method overview

Analysis of intact protein mass using ESI-TOF. This analysis allows for the elucidation and verification of whole protein mass, including analysis of custom covalent post-translational modifications or protein degradation products. It allows for relative quantification of individual proteoforms in the sample. Examples of common applications are antibody-drug conjugate analysis, analysis of methylation of histones or verification of mass and homogeneity of produced proteins, as a more precise alternative to SDS-PAGE.

Contact: František Filandr

Example of an analysis of antibody-drug conjugate heavy chain featuring variable drug binding.

Requirements:

  •     Ideally pure protein in suitable buffer solution
  •     Any buffer not containing detergents or excessive salt amounts (>250 mM) is usable
  •     Transfer of protein into 200 mM ammonium acetate can help improve data quality
  •     Protein sequence
  •     List of expected masses of modifications
  •     Precise buffer composition

Results:

  •     List of masses found in the sample and their relative ratios. In case of a single pure protein, the result should be a single dominant mass. In case of natural PTM presence, additional signals may appear based on populations of proteoforms in the sample.
  •     Results in the form of HTML report from UniDec software, showing detected mass, their relative ratios, mass precision and graphical visualization.
  •     Results in the form of .txt file containing deconvoluted zero-charge mass spectra in coordinate formate. This can be opened for example in mMass software (provided upon request).
  •     Data interpretation based on information provided by requester in the reQuest system.

Expected turnaround time:

  •     Within 24 hours

To start an intact protein mass analysis request, use the reQuest system (Link Here)