MALDI-TOF Mass Spectrometry in Protein Analytics

MALDI-TOF MS (matrix assisted laser desorption ionization time-of-flight MS) is a mass spectrometry method that is widely used in protein and glycan research. The new generation MALDI mass spectrometers allow a precise mass determination of proteins, peptides and glycans as well as the fragmentation (=MS/MS) of these to derive protein or peptide sequence data. This increases the confidence in protein or peptide identification significantly.

MALDI-MS is perfectly suited for the detailed structural characterization of proteins, including the analysis of post-translational modifications (PTM) and for the analysis of glycan pools.

For the analysis of the MALDI MS and MS/MS data sets, Protagen has developed algorithms that allow getting more information out of the mass spectra.

MALDI-MS can be employed in a wide range of biochemical applications ranging from peptides to proteins and glycans, such as:

• determining the molecular weight of intact proteins. This can be used to confirm the identity of a protein, screen for protein modifications or to use the molecular weight for the calculation of the mass extinction coefficient or mass concentration.
• Identifying proteins, e.g. after 1D or 2D gel electrophoresis as well as in the in-depth characterization of proteins and PTMs.
• MALDI-TOF MS can be used for the proof of identity according to ICHQ6B.

The sample is mixed with a matrix, crystallized on a MALDI target and ionized using a UV laser system. The ions are then detected in a time-of-flight analyzer. The data sets are then imported into a relational database for further data reprocessing and evaluation.

MALDI MS is used or can complement a large range of further analysis such as:

• Amino acid analysis
• Peptide mapping
• De-novo protein sequencing
• N- and C-terminal sequencing (MALDI-ISD)
• Disulfide linkages analysis
• Analysis of post-translational modifications (such as oxidation, deamidation)
• Glycosylation analysis
• Proteomics
• Protein identification
• Process- or product-related impurity testing
• Release testing

As a complementary mass spectrometry approach, Protagen offers liquid chromatography coupled with electrospray ionization MS (LC-ESI-MS and LC-ESI-MS/MS). For N- and C-terminal sequencing of proteins, we recommend the MALDI-ISD technique.

Protagen’s protein analysis package is designed to encompass the requirements of ICH guidelines (in particular ICH Q6B).

Your contact for MALDI-TOF Mass Spectrometry in Protein Analytics at Protagen AG

Dr Katja Aschermann Head of Business Development Protein Services. Her team will be happy to assist you with your project. Phone: +49 (0) 231 9742-6300 Email: salesproteinservices@protagen.de