Radiolytic degradation scheme for 60Co-irradiated corticosteroids

Article abstract of DOI:10.1002/jps.2600720108

The cobalt 60 radiolytic degradation products have been identified in the following corticosteroids: cortisone, cortisone acetate, hydrocortisone, hydrocortisone acetate, hydrocortisone sodium succinate, isoflupredone acetate, methylprednisolone, methylprednisolone acetate, prednisolone, prednisolone acetate, and prednisone. Two major types of degradation processes have been identified: loss of the corticoid side chain the D-ring to produce the C-17 ketone and conversion of the C-11 alcohol, if present, to the C-11 ketone. Minor degradation products derived from other changes affecting the side chain are also identified in several corticosteroids. These compounds are frequently associated in corticosteroids as process impurities or degradation compounds. No new radiolytic compounds unique to ⁶⁰Co-irradiation have been found. The majority of corticosteroids have been shown to be stable to ⁶⁰Co-irradiation. The rates of radiolytic degradation ranged from 0.2 to 1.4%/Mrad.