Product DescriptionABD-F has a benzofurazan moiety that produces a highly fluorescent compound through the reaction with a sulfhydryl group. The excitation and emission of the devivatized compound are 389 nm and 513 nm, respectively. The reaction rate of ABD-F is 30 times faster than that of SBD-F. ABD-F reactions with thiol compounds are completed within 5 minutes in aqueous conditions at 50ºC, pH 8. However, ABD-F does not react with alanine, proline, or cystine under these conditions. Its maximum fluorescence intensity can be observed at pH 2. In reversephase HPLC analysis, pre-labeled ABD-thiol compounds can be detected separately. The detection limits (S/N=3) are 0.6 pmol per injection for cysteine, 0.4 pmol per injection for glutathione, 1.9 pmol per injection for N-acetylcysteine, and 0.5 pmol per injection for cysteamine.

ABD Labeling Protocol1. To prepare sample solution, mix or dissolve a sample with 100 mM borate buffer, pH 8.0 containing 2 mM EDTA.2. Mix 500 μl of the sample solution and 500 μl of 1 mM ABD-F/100 mM borate buffer in a reaction vial.3. Heat the vial at 50ºC for 5 minutes and cool it on an ice bath.4. Add 300 μl of 100 mM HCl aqueous solution to the reaction mixture.5. Use this mixture for HPLC analysis to determine ABD-labeled compounds; excitation: 389 nm, emission: 513 nm.

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