Kit for preparing sample for detecting monoclonal antibody

A method for preparing a sample for detection of a monoclonal antibody through high-performance liquid chromatography-mass spectrometry, comprising:

• providing porous bodies having pores and a target monoclonal antibody immobilized in the pores of the porous bodies, and nanoparticles having an immobilized protease;
• bringing the porous bodies and the nanoparticles into contact with each other in a buffer in a reaction vessel comprising a filtration membrane such that the target monoclonal antibody in the porous bodies and the immobilized protease on the nanoparticles undergo a selective protease proteolysis reaction in the reaction vessel;
• and
• applying pressure or centrifugal force to the reaction vessel containing the buffer such that the buffer and digested peptide fragments produced through the protease proteolysis reaction permeate through the filtration membrane and that the filtration membrane prevents permeation of the porous bodies and the nanoparticles,
• wherein the filtration membrane has a pore size set in a range that allows permeation of the digested peptide fragments produced through the protease proteolysis reaction and prevents the permeation of the porous bodies and the nanoparticles.