Studies on the interaction of tetracyclines with albumin by fluorescence spectroscopy

The quenching fluorescence of albumin by tetracyclines was studied by fluorescence Spectroscopy. The dissociation constants between tetracyclines�� medicine with HSA or BSA were obtained according accorded to static quenching and Scatchard equation. These results accorded with those from the other methods, and showed that the interaction process was static quenching. By use of a spectra overlap intergral between the absorption spectrum of these compounds and the emission spectrum for HSA or BSA, the distance of Trp residue to these compounds was estimated. In addition, the binding mechanism was discussed in brief and an model of a tetracycIines-HSA or a tetracyclines-BSA non-fluorescent complex was pc-stulated from above results.