|dc.description.abstract||Bovine serum albumin, BSA, is often used in molecular biology, immunology, nutritional science or protein chemistry, due to its stability, inhibition of lipid peroxidation, emulsification and antifreeze effects. In addion, BSA’s low cost and easy to purify make it a good candidate for experiment and as a reference protein. BSA has a spherical structure that formed by the tightly folding of the secondary structures. In the elevated temperature, the native BSA gains kinetic and results in a strong vibration causing the damage of the molecule bonding. The 3D structure is then unfolds and turned into the denatured state. In order to study the thermal denaturation of protein, researchers commonly use differential scanning calorimetry method, DSC, to investigate the changes in enthalpy, entropy and specific heat by measuring the heat flow in the elevated temperature. The thermal denaturation effects on the heat transport properties of proteins, however, that is seldom investigated and may have potential impacts on biomedical applications.
In this study, we used DSC to explore the relationship between BSA solutions and the heat flow in the thermal denaturation process. Additionally, laser flash analysis, LFA, was use to study the effective thermal diffusivity of BSA solutions with various concentrations. The time dependence of the thermal diffusivity was also considered. Experiments had performed to measure the density, specific heat, and effective thermal diffusivity of BSA solutions with concentrations 5 ~ 20 wt%. The effective thermal conductivity was then calculated. We found that the energy required in the denaturation process increased with BSA concentration. Same trend can be found in the variation of specific heat. In the thermal diffusivity analysis, LFA couldn’t reveal the true thermal diffusivity when undego denaturation, but reflected the impact of different degrees of thermal denaturation process on heat transfer phenomena. The variation of thermal diffusivity caused by the thermal denaturation process was more dramatic with the increasing concentration. It also showed a linear relation between the thermal diffusivity and durtaion time. The change rate of thermal diffusivity increased with temperature and concentration, which means the increase in the degree of thermal denaturation process.