Exploring the interaction of L-cysteine capped CuS nanoparticles with bovine serum albumin (BSA): a spectroscopic study

The interactions between nanoparticles and proteins have prime importance in nanomedicine and nanotoxicology. L-Cysteine capped copper sulfide (Cy-CuS) nanoparticles having average particle size of 6 nm have been synthesized using chemical coprecipitation method and their interactions with Bovine Serum Albumin (BSA) were explored using various spectroscopic techniques. A ground state complex is formed between BSA and Cy-CuS nanoparticles in solution. The number of binding sites, binding constant, quenching constant and the binding distance between Cy-CuS nanoparticles and BSA were determined. The overall conformation of BSA in the complex was unaltered, however the a-helical content of BSA was marginally reduced.