Influence of the degree of iodination and storage time of the immunological activity of 125I-IgE

Stability of 125I-Labeled Staphylococcal Enterotoxins in Solid-Phase Radioimmunoassay

“…Stability of a preparation of SEA labeled with 125I at 37 MCi of protein per Mg (A) and 3 MCi of protein per Mg (0). Reaction time was 2 min, and storage temperature was -23 C. 4 tCi/,ug of protein), although initially similar in amount to that of toxins with high specific activity, does not increase in amount on storage for as long as 60 days at -23 C. Aggregates were not found in untreated enterotoxins, so their presence in radiolabeled enterotoxins resulted from the labeling procedure (data not shown). Table 2 contains data on the immunoreactivity of the monomeric and aggregate fractions of high-specific-activity 125I-labeled enterotoxins.…”

The Role of Pharmacokinetics in the Development of Biotechnologically Derived Agents

“…Additionally, iodination has a separate set oflimitations. Iodination has the potential to alter biological activity or to influence the disposition of the peptide or protein (Ceska et al 1972;Regoeczi 1987b). These limitations are attributed to the inherent properties of iodine; namely, iodine is not a natural constituent and has a high molecular weight.…”