Calculation of van't Hoff enthalpy associated with aspirin-induced change in liposomal membrane anisotropy

The lipid disordering effect of aspirin on the liposomal membrane of dipalmitoyl phosphatidyl choline has recently been studied using the fluorescence polarization method. From the anisotropy-temperature curve, we have calculated here the associated change in van't Hoff enthalpy. Since the fluorescence technique requires a very small amount of sample (10(-4) M), this method of enthalpy calculation compares well and is advantageous over the standard calorimetric methods.