Binding studies of costunolide and dehydrocostuslactone with HSA by spectroscopy and atomic force microscopy

► Interactions of costunolide and dehydrocostuslactone with HSA have been investigated for the first time. ► Raman spectra were used to analyze the drug-HSA interactions. ► Atomic force microscopy has been used to study the topography change of HSA by addition of the drugs. ► These results are important for the drugs containing costunolide and dehydrocostuslactone distribution and metabolism.