Interactions of folic acid and deoxycholic acid with bovine serum albumin as well as the effects of coexisting paclitaxel

Fluorescence quenching method was used to study the interactions of folic acid and deoxycholic acid(DH) with bovine serum albumin(BSA) with or without coexisting paclitaxel(PA).The results indicated that FA and DH could quench the inner fluorescence of BSA by forming the FA-BSA complex or the DH-BSA complex.Both static quenching and non-radiative energy transfer was confirmed to be the result in the fluorescence quenching.The binding force of FA and DH was mainly hydrophobic force and the binding sites of FA and DH were mainly in the site II.The interaction of FA with BSA was strengthened，and that of DH with BSA was weakened while coexisting with PA.