Spectroscopic exploration of interaction between PEG-functionalized Ag2S nanoparticles with bovine serum albumin

Highlights: • The interactions of BSA with PEG capped Ag₂S nanoparticles were investigated using spectroscopic techniques. • Quenching of BSA fluorescence is occurred after complexation with Ag₂S nanoparticles. • The overall conformation of BSA is unaltered after complexation with PEG-Ag₂S nanoparticles. The introduction of nanoparticles into biological fluids often leads to the formation of biocorona over the surface of nanoparticles. For the effective use of nanoparticles in biological applications it is very essential to understand their interactions with proteins. Herein, we investigated the interactions of Poly ethylene glycol capped Ag₂S nanoparticles with Bovine Serum Albumin by spectroscopic techniques. By the addition of Ag₂S nanoparticles, a ground state complex is formed. The CD spectroscopy reveals that the secondary structure of BSA is altered by complexation with PEG-Ag₂S nanoparticles, while the overall tertiary structure remains closer to that of native BSA.