Moleclar Mechanism Of The Interaction Of UV-filters With Serum Albumin

The organic sunscreen was widely used in daily life, which is highly hydrophobic and chemically stable, and residued in various environmental compartments and body of organism, are emerging contaminants attracting highly attention to their toxcilogical mechanis. In this study, two typically classes of UV sunscreens, the benzotriazole (BZTs) and benzophenone (BPs) analogues were chosen to be investigated their transportational mechanism in vivo. Their interactions with human serum albumin (HSA) and bovine serum albumin (BSA) were probed base on the combined spectroscopies and molecular docking method, and the interaction mechanism was elucidated at the molecular level. The mainly obtained results and conclusions are as following:(1) The interactions of BP-1, BP-2, BP-3, BP-8with HSA were investigated. The binding affinities of BPs to HSA rank as BP-8> BP-1> BP-3> BP-2. The difference in the binding affinities was associated with the difference in chemical strutures of BPs. The changes in structural moieties and LogKow of four benzophenones account for their different binding affinities. Four BPs bind at the site II of HSA. BP-8interacts with HSA mainly through hydrogen bonding interactions and vander Waals interactions, however, BP-1, BP-2, BP-3interact with HSA mainly via hydrophobic interactions and electrostatic interactions. All of BPs can cause structural changes of HSA in varying degrees. The BPs possesses stronger affinity to HSA tend to cause the conformational change of HSA more significantly.(2) The interaction of six BZTs with HSA/BSA was investigated. UV-326, UV-327, UV-328, UV-329,1H-BT, UV-P, bind at site I of HSA. UV-326, UV-327, UV-328interacts with HSA/BSA mainly through hydrogen bonding interactions and Vander Waals interactions, while hydrophobic interactions and electrostatic interactions are dominant for interactions between UV-327, UV-329,1H-BT and HSA/BSA. All of these BZTs can cause changes in conformation of HSA/BSA. The ranking for the binding affinities of BZTs to BSA was UV-329>UV-P>UV-326>UV-327> UV-328>1H-BT, and the ranking for the binding affinity of BZTs to BSA was UV-329>UV-P>UV-328>UV-326>UV-327>1H-BT.