Bolton-Hunter Reagent, [¹²⁵I]- or [¹³¹I]-

The PerkinElmer Bolton-Hunter Reagent, [¹²⁵I]- is the N-hydroxysuccinimide ester of iodinated p-hydroxyphenylpropionic acid, originally described by Rudinger and Ruegg.3 The active ester acylates terminal amino groups with the iodinated p-hydroxyphenylpropionic residue, making this an effective way to introduce radioactive iodine into a variety of proteins and peptides. It is a non-oxidative technique which is less harsh to proteins than alternative methods. Proteins and peptides, such as TSH, hGH, insulin, and hLH labeled with this technique, have demonstrated a high retention of immunoreactivity.

References:
Rudinger, J., and Ruegg, U., Biochem.J. 133:538 (1973).
Bolton, A.E., and Hunter, W.M., Biochem.J. 133:529 (1973).