Effects of interaction between non-steroidal anti-inflammatory drugs with BSA and DNA base : Spectral, electrochemical and molecular docking methods

Department of Chemistry, Annamalai University, Annamalai Nagar-608 002, Tamilnadu, India

E-mail : drrajendiran@rediffmail.com

Manuscript received online 09 April 2016, accepted 03 October 2016

To evaluate the role of hydrophobic and electrostatic interactions of BSA and DNA base (adenine) with two different non-steroidal anti-inflammatory drugs, [meloxicam (MEX) and piroxicam (PIR)]. Both drugs have different heterocyclic rings. The binding affinity for the protein-drug formation is found to depend primarily on the different heterocyclic rings or functional groups like OH, C=O, NH, etc. suggesting the essential role of hydrophobic forces, supported by hydrogen and polar bonding interactions at the protein surface. UV-Visible, fluorescence, IR, cyclic voltammetry and molecular docking analysis were performed to compare the effects of heterocyclic rings of two drugs on BSA/adenine. The fluorescence spectral blue shift suggested that both drug molecules strongly interacted with BSA. The difference in the IR spectrum of BSA, pure drugs and complex confirm the interactions between the drugs to BSA. With an increase the concentration of drugs, the oxidation peaks of MEX and PIR were shifted to higher potential (E_pa) and the oxidation peak current (I_pa) is also increased. These observations suggested the formation of non-electroactive interactions between BSA/adenine with drug molecules. Docking analysis showed PIR strongly interacted with BSA rather than MEX