Voltammetry of Os(VI)-Modified Polysaccharides at Carbon Electrodes

We show that polysaccharides (PSs, such as dextran and mannan) can be chemically modified by Os(VI) complexes, yielding electroactive adducts. Os(VI) complexes with different ligands (e.g., temed and 2,2'-bipyridine) produced at pyrolytic graphite electrodes redox couples at different potentials suitable for multicolor labeling of PSs and for studies of ligand exchange kinetics. PS-Os(VI)L adducts can be determined not only in their purified forms but also in the reaction mixtures.