PROTECTION OF BIOLOGICALLY ACTIVE MOLECULES DURING RADIATION STERILIZATION

Compositions and methods are disclosed that relate to protecting biological activity of a biologically active molecule, including a biologically active protein or biological response modifier such as an immune response modifier, against radiation damage during radiation sterilization. Inclusion of at least one radio-protectant compound, for example, cysteine, reduced glutathione, melatonin, and/or histidine, in an exemplary mitogenic lectin formulation during spray-drying onto surfaces of immunoassay tubes, surprisingly protected the lectin against loss of biological (mitogenic) activity that would otherwise result from electron beam radiation sterilization. The radioprotectant compound also protected other biologically active molecules and stabilized their biological activities, permitting them to retain biological activity after extended storage following the radiation treatment.