Peptide fragment preparation method, peptide fragment preparation kit used therefor, and analysis method

摘要

The present invention relates to a method for preparing a peptide fragment by cleaving a protein using a protease. The method of the present invention comprises a porous body (20) in which a substrate protein (25) to be cleaved is immobilized in pores (29), and a microparticle (10) in which protease (15) is immobilized on the surface. Contacting in a liquid. In the present invention, the average particle diameter of the fine particles (10) is larger than the average pore diameter of the porous body (20). According to the method of the present invention, the substrate protein (25) of the antibody can be cleaved regioselectively. By analyzing the peptide fragment obtained by the above method by mass spectrometry or the like, antibody protein detection or quantitative analysis can be performed.