LC-MALDI-MS/MS method

The LC-MALDI-MS/MS method is effective in identifying proteins separated by SDS-PAGE. It is also effective when multiple types of proteins coexist after they are separated by two-dimensional electrophoresis.

Peptides obtained by treatment of multiple types of proteins with a digestive enzyme may coexist with similar molecular weights. When the MALDI method is used, there are large differences in the ionization efficiencies of the coexisting peptides. When obtaining peptide sequence data by the MS/MS method, it is important to ensure sufficient signal intensity of the peptides in order to identify them with high precision. For this reason, peptides should be purified as much as possible when the MALDI method is used. Fractionation by nanoflow reversed-phase HPLC is effective in separating trace samples.

Principle of the LC-MALDI-MS/MS method

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