Studies on Interaction of Polysaccharide-Templated Silver Nanoparticles with Bovine Serum Albumin

In the present work, the interaction between bovine serum albumin (BSA) and as-synthesized silver nanoparticles (Oc-AgNPs) by using 4-acetamido-TEMPO-oxidized curdlan (Oc), as a reducing and stabilizing agent, was studied through fluorescence quenching method, ultraviolet visible spectrum (UV–Vis), and circular dichroism measurement. The results presented clearly indicate that the intrinsic fluorescence of BSA molecule was effectively quenched after the interaction with Oc-AgNPs by a static mechanism, which is further confirmed by UV–Vis analysis. The apparent binding constant (K), number of binding sites (n), and dissociation equilibrium constant (K_D) were calculated to be 7.5 × 10⁵ M^?1, 1.03, and 3.0 ± 0.6 μM, respectively. Furthermore, a conformational change of BSA was also observed when the Oc-AgNPs–BSA interactant formed.