Subsequently, the carbon double bonds involved in the copolyester main chain were subjected to dihydroxylation with catalyst of osmium tetroxide (OsO4), N-methylmorpholine N-oxide (NMO) and water to prepare novel biodegradable copolyesters bearing hydrophilic hydroxyl pendant groups.
Methods: Ruthenium tetroxide and osmiumtetroxide were compared as post fixative in the preparation of hairless epidermis for transmission electron microscopic examination.