Enhanced MALDI-MS Analysis of Peptides Using Amphiphilic Homopolymers
Selective and enhanced detection of peptides from complex mixtures. A special class of polymers is used to selectively extract and concentrate peptides of interest from complex mixtures, while simultaneously enhancing their detection using matrix-assisted laser desorption/ionization (MALDI) mass spectrometry.
Mass spectrometry is perhaps the most important tool used in proteomics studies; however, the complexity of proteomic samples and the wide concentration range of peptides and proteins in these samples require effective extraction or fractionation protocols to take full advantage of mass spectrometry's power. This invention can be used to selectively extract and concentrate peptides from complex mixtures while providing sensitivities in the attomole range. This new technique will have applicability in protein identification, peptide biomarker discovery, and diagnostic methods that rely on sensitive peptide analyses.
These polymers can selectively extract peptides based on their isoelectric point with efficiencies close to 100%. When used in a simple two-phase extraction system, peptides can be concentrated 30- to 100-fold while maintaining the desired selectivity. Furthermore, the presence of the polymers during the MALDI-MS analysis actually leads to an order of magnitude or greater increase in peptide ionization efficiency.
Ling X. Shen, Ph.D., M.B.A.
Commercial Ventures and Intellectual Property