I am a home-chemist and I love dyes. I recently got my hands on sodium salt of erythrosine (tetra-iodinated fluorescein). I want to convert erythrosine to fluorescein. I speculate that using dilute NaOH solution might cause formation of sodium iodide and tetra-hydroxylated fluorescein. How can I reduce the alcohol groups without affecting the carboxylic acid groups.
Is there any better way to convert erythrosine to fluorescein?