Chemiluminescence Detection of Amino Acids, Peptides, and Proteins Using Tris-2,2′-Bipyridine Ruthenium (III)

The feasibility of using the tris-2-2′-bipyridine ruthenium (III) (Ru(bpy)3 3 +) chemiluminescent (CL) reaction for the detection of amino acids, peptides, and proteins has been studied. Detection limits of the amino acids as determined by flow injection analysis (FIA) ranged from 20 pmol of proline to 50 nmol of asparagine. In general, amino acids containing secondary amine groups yielded the strongest responses. A reaction mechanism for Ru (bpy)3 3 + chemiluminescence of aliphatic amines has been proposed. Studies of peptide molecules and poly-prolines showed that the peptide bond barely contributes to the detection signals. The separation of hydroxyproline and proline in synthetic collagen by HPLC with Ru (bpy)3 3 + chemiluminescence detection has been shown to be possible.