Ultraviolet radiation can cause the unfolding and destabilization of proteins. By using high energy photons from a synchrotron radiation source, we show that the UV-induced destabilization of human serum albumin (HSA) can be detected and monitored by measuring the circular dichroism spectrum of the protein. The high flux radiation source damages the HSA protein by causing a partial unfolding of the protein and a significant reduction in the amount of its secondary structure. Gold nanoparticles can effectively stop this UV-induced unfolding of HSA caused by synchrotron radiation. These phenomena could offer interesting applications to protect HSA protein from UV-induced damage and provide an alternative method to measure the relative stability of HSA.