The thermodynamic and kinetic behavior of green-synthesized silver nanoparticles (AgNPs) interacting with bovine serum albumin (BSA) was studied using UV–Visible spectroscopy and conductivity techniques. AgNPs prepared from Azadirachta indica leaf extract showed a surface plasmon resonance (SPR) band at 430 nm. Binding constants (K) were measured at five temperatures (298–318 K). Van't Hoff analysis provided ΔH and ΔS, while ΔG was evaluated at each temperature. The interaction is spontaneous (ΔG < 0) and shows an endothermic signature from the derived ΔH. Conductivity and UV–Visible spectroscopy (not shown) support complex formation and changes in protein environment upon binding. We investigated how temperature affects the binding between the molecules. Our examination of the thermodynamic data verified that the contact is endothermic—that is, it takes in heat from its environment—and occurs spontaneously. We also kept an eye on electrical conductivity variations. Complex formation was confirmed by conductivity studies.
