Is there a suitable chromaphore that can be conjugated, using a one pot method, to an m-PEG with a di-amine, -OH, or an amine end group? This will in turn be analyzed using a UV detector on an HPLC. We are wanting to determine the presentation and quantity of each species in a single HPLC sample prep and run to determine substitution of the PEG functional groups and mole % of each species.