Fluorescein iodoacetamido derivatives

The iodoacetamido derivatives of fluorescein possess a sulfhydryl-reactive iodoacetyl group (Chapter 1, Section 4.2 and Chapter 2, Section 2.1) at either the 5- or 6-carbon position on their lower ring. The isomers are commercially available in purified form, since some reactivity and specificity differences between the 5- and 6-derivatives toward various sulfhydryl sites in proteins may be observed. Both iodoacetamido derivatives are among the most intense fluoro-phores available for labeling biomolecules due to high QY. 

The 5-iodoacetamido derivative of fluorescein (5-IAF) has been used to label numerous proteins and other biomolecules, including actin (Plank and Ware, 1987), myosin (Aguirre et al., 1986), troponin (Greene, 1986), hemoglobin (Hirsch et al., 1986), and sulfhydryl-containing proteins separated by SDS electrophoresis (Gorman, 1984). 

The iodoacetamido derivatives of fluorescein possess a sulfhydryl-reactive iodoacetyl group (Chapter 1, Section 4.2, and Chapter 2, Section 2.1) at either the 5- or 6-carbon... 

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