Answer:
Hundreds of proteins have been sequenced by Edman degradation of peptides derived from specific cleavages. Protein Mass Spectrometry is an analytical technique that measures the mass-to-charge ratio of charged particles for determining masses of particles and the elemental composition of a sample of molecules as well as for elucidating the chemical structure of molecules such as peptides. Protein mass spectrometry is an important method for the accurate mass determination and characterization of proteins, and a variety of methods and instrumentations have been developed for its many uses.