The interaction between lanthanide cationic porphyrin and bovine serum albumin (BSA) was studied by fluorescence and UV-Vis spectrum. The static quenching of BSA was observed in the presence of YbTMPyP. According to the thermodynamic parameters, this binding was regarded as "enthalpy-driven" reaction. Furthermore, YbTMPyP is so close to the residues of BSA that molecular resonance energy transfer occurs between them. Besides, the red drift and hypochromicity of absorption spectrum of YbTMPyP were accompanied with the binding reaction.
Flavonols are plant nature. Morin and other related pigments that are ubiquitous in plant flavonols have come into recent prominence because of their usefulness as anticancer, antitumor, anti-AIDS, and other important therapeutic activities of significant potency and low systemic toxicity. The heat of combustion of morin (molecular formula, C15H10O7·H2O) in oxygen was measured by a rotating-bomb type combustion calorimeter, the standard molar enthalpy of combustion of morin at T = 298.15 K was determined to be △cH^ m (C15H10O7·H2O, s) = - (5 937.99±2.99) kJ·mol^-1. The derived standard molar enthalpy of the formation of morin in solid powder state at T = 298.15 K, △fH^ m(C15H10O7·H2O, s), was -(1 682.12 ± 3.58) kJ·mol^1, which provide an accurate data of the stability of morin to the pharmacy and pharmacology.