Micro method for determination of reactive carbonyl groups in proteins and peptides, using 2,4-dinitrophenylhydrazine

A method is described for determining carbonyl groups that is especially suitable for use with proteins and peptides. It involves the determination of the extinction at 370nm of a sample solution after adding 2,4-dinitrophenylhydrazine. The reaction of 2,4-dinitrophenylhydrazine with pyruvoylglycine and with transaminated ribonuclease T(1) is presented; the isolation of protein hydrazones is discussed.