I3C can be used for heavy atom derivatization of biological macromolecules for subsequent single wavelength anomalous dispersion (SAD) or single isomorphous replacement plus anomalous scattering (SIRAS).
The two carboxylic acid groups and one amino group of I3C can interact by way of hydrogen bonds with both the backbone and side chains of proteins. This can result in a relatively high occupancy of the bound ligand I3C. The three iodine atoms per I3C molecule provide for a strong anomalous signal.
With three iodine atoms per molecule it provides a strong anomalous signal, even for in-house X-ray sources, as the anomalous scattering signal f′ of iodine is 6.85 electron units at the Cu κα wavelength of 1.54 Angstrom.
The three iodine atoms in I3C form an equilateral triangle with 6.0 Å side lengths. These triangular structures can readily be identified in the anomalous electron density map.
Kit Contents • 12 aliquots of I3C (280 mg each) - Synonym: 5-Amino-2,4,6-triiodoisophthalic acid - CAS Number [35453-19-1] • 12 aliquots of 2.0 M Lithium hydroxide (650 µl each) - CAS Number [1310-65-2] • User Guide
