Spectroscopic investigation on the intermolecular interaction between N-confused porphyrins-(3-methylisoxazole) diad and bovine serum albumin

The intermolecular interaction between N-confused porphyrins-(3-methylisoxazole) diad (NCP-(3-methylisoxazole)) and bovine serum albumin (BSA) has been investigated through fluorescence and ultraviolet spectroscopy at different temperatures under imitated physiological conditions. The results showed that the fluorescence of BSA was quenched by NCP-(3-methylisoxazole) through a combined quenching procedure. The characteristics of NCP-(3-methylisoxazole)⋯BSA interaction (including interaction nature, interaction conformation, binding constants, binding sites, binding distance, thermodynamic parameters, etc.) and the effect of metal ions (Cu2+, Mg2+, Ca2+, and Ni2+) upon the NCP-(3-methylisoxazole)⋯BSA interaction have been detailed studied.

The interaction between N-confused porphyrins-(3-methylisoxazole) diad (NCP-(3-methylisoxazole)) and bovine serum albumin (BSA) was studied by fluorescence and UV–vis spectroscopy. The quenching mechanism, binding constants, thermodynamic parameters, and binding distance were obtained.Figure optionsDownload as PowerPoint slideHighlights
► The interaction of BSA and NCP-(3-methylisoxazole) was researched.
► The fluorescence quenching mechanism is combined quenching.
► Hydrophobic interaction force plays a major role in stabilizing the complex.
► The binding constant, ΔG, ΔH, and ΔS of the interaction were calculated.
► The conformation of BSA is changed in the presence of NCP-(3-methylisoxazole).