Chemiluminescent detection of amines and amino acids using in situ generated Ru(bpy)(3)(3+) following separation by capillary electrophoresis

A new sensitive chemiluminescent detection method for capillary electrophoresis is described. Underivatized amines and amino acids were detected following capillary electrophoresis separation by their chemiluminescent reaction with Ru(bpy)(3)(3+) generated in situ at 35 mum carbon fibers. Detection limits for triethylamine and proline were 5 and 3 fmol, respectively at a SNR of three. The noise limiting the detectability of separated analytes was determined to exist at the level of the dark noise limit of the PMT used for these studies and additional noise reduction strategies are expected to improve the quantitative aspects of the method. Theoretical plate numbers for proline were approximately 20 000. End column addition of Ru(bpy)(3)(2+) coupled with in situ generation of Ru(bpy)(3)(3+), has been shown to be compatible with the nanoliter elution volumes characteristic of capillary electrophoresis.