1-Fluoro-2,4-dinitrobenzene, GR 99%+ Cas 70-34-8 - used in elucidating amino acid sequence in proteins. Dinitrofluorobenzene reacts with the amine group in amino acids to produce dinitrophenyl-amino acids. These DNP-amino acids are moderately stable under acid hydrolysis conditions that break peptide bonds. The DNP-amino acids can then be recovered, and the identity of those amino acids can be discovered through chromatography. 1-Fluoro-2,4-dinitrobenzene, GR 99%+ Cas 70-34-8 used for the rather difficult analysis of distinguishing between the reduced and oxidized forms of glutathione and cysteine in biological systems in conjunction with HPLC. This method is so rugged that it can be performed in such complex matrices as blood or cell lysate.