indicating that the thermodynamic mechanism may be not changed in the temperature range studied. However,the apparent binding constants decrease monotonically with temperature,showing that the intrinsic bond formation of AuNPs-HSA conjugate is exothermic. To further clearly delineate the potential molecular forces contributing to the formation of AuNPs-HSA conjugate,three thermodynamic quantities related to the formation of AuNPs-HSA conjugate,standard enthalpy change,