Influence of nanoparticle size on the pH-dependent structure of adsorbed proteins studied with quantitative localized surface plasmon spectroscopy

We have studied p H-dependent conformational transitions of Bovine Serum Albumin adsorbed onto different sizes of gold nanospheres. For larger spheres (D > 10 nm) there is evidence for a path-dependent extended state near p H 4, over a very small p H range. For smaller nanospheres (5nm and 10nm) the evidence for such a transition is either much weaker or completely suppressed. We suggest that the absence of the transition on small spheres is …