Iodination Reagents for Proteins
Iodination involves the introduction of radioactive iodine into certain amino acids (usually tyrosines) in proteins and peptides. Iodination takes place at the positions orthogonal to the hydroxyl group on tyrosine; mono- or di-substitution can occur. When iodinatable sites such as tyrosines are absent or of limited accessibility, iodinatable phenolic sites can be introduced by using the Bolton-Hunter Reagents (SHPP and Sulfo-SHPP). Certain crosslinkers also contain iodinatable tyrosyl groups in their spacer arms.
Radioactive I-125 or I-131 can be incorporated into proteins either by enzymatic or chemical oxidation. In the chemical oxidation method, sodium iodide is converted to its corresponding reactive iodine form, which then spontaneously incorporates into tyrosyl groups. While necessary for iodine activation, oxidizing reagents are potentially damaging to proteins.
Comparison of Thermo Scientific™ Pierce™ iodination products
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 |
 |
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|---|---|---|---|
| Iodination reagent | Iodination tubes | Iodination beads | |
| Detergent compatible | ✓ |
✓ |
✓ |
| Denaturant compatible | ✓ |
✓ |
✓ |
| pH range | 4.4 to 9.0 (8 to 9 optimum) |
4.4 to 9.0 (8 to 9 optimum) |
4.0 to 8.5 (5.0 to 6.5 optimum) |
| Stability | Stable indefinitely | Stable indefinitely | One year |
| Ease of use | Requires good plating technique |
Easy | Easy |
| Order now | Order now | Order now |
Resources
For Research Use Only. Not for use in diagnostic procedures.
