STUDY ON THE REACTION OF MONOFUNCTIONAL FLUORESCENT REAGENTS IN ORGANIC SOLUTIONS BY FLUOROMETRY.

Article abstract of DOI:10.1246/bcsj.55.3068

Reactions of some fluorescent reagents with substrates, used widely in biochemistry for quantitative analysis of some functional groups in aqueous media, have been studied in organic solutions with a view that they may be used also in the area of synthetic polymer science. Reactions studied by fluorometry were (i) 5-dimenthylamino-1-naphtalensulfonyl chloride with butylamine, (ii) 2-naphthalensulfonyl chloride with butylamine, and (iii) N-(1-naphthyl)maleimide with 1-pentanethiol. In polar solvents all the fluorescent probes studied are too labile and converted spontaneously into fluorescent compounds. In less polar solvents, however, such side reactions do not take place and the reaction of fluorescent reagents with substrates proceeds quantitatively with a simple second-order kinetics. The second-order rate constants for the three reactions are of the order of 10** minus **3 to 10** minus **1 M** minus **1 s** minus **1 in the range of about 30 to 50 degree C, and they increase with the solvent polarity. This work is pertinent to polymers.