Study On The In-situ Interaction Of Nano-Fe₂S₃ And Nano-CoS With Gelatin

Currently, the research on biological effects of nanoparticles is mainly fromthe biological overall level, cellular level, molecular level, and the environmentlevel and so on. At the molecular level, we can better explain the essence of theinteraction between nano-materials and biological macromolecules. The thesis firststudy the in-situ interaction between the nano-Fe₂S₃ and nano-CoS with gelatinprotein, The main points as follows:1. Nano-Fe₂S₃ and nano-CoS were prepared in the gelatin solution.2. The in-situ interaction between the nano-Fe₂S₃ and nano-CoS wereinvestigated by means of UV-visible absorption spectra (UV-Vis). Theexperimental results show that the fitted equation of in-situ interaction of thenanoparticles followed the pseudo-first-order reaction, obtaining the apparentactivation energy, apparent pre-exponential factor and thermodynamic parametersof activation. According to the Line weave-Burk equation, the constant (K)and thethermodynamic parameters in corresponding temperature were obtained.3. The in-situ interaction of gelatin protein with the nano-Fe₂S₃ and nano-CoShas been studied using fluorescence spectroscopy, synchronous fluorescencespectroscopy and magnetic resonance fluorescence spectroscopy. It has been foundthat the formation of nanoparticles has a strong ability on the fluorescencequenching of the gelatin protein in the gelatin solution. The fluoreseencequenching mechanisms, the binding constants and the main interaction foreeinvolving in the interaction of nanoparticles and gelatin proteins were confirmedby Stern-Volmer equation, Scatchard equation and Van't Hoff equation.The studyalso shows that the data of synchronous fluorescence spectroscopy and resonancerayleigh light scattering spectra, which is from the action of nano-Fe₂S₃ andnano-CoS on the gelatin protein, is also suitable for the research on quenchingconstants, bimolecular quenching rate constants, reaction constants (K) andthemodynamics parameters. According to F?rster's the energy transfer theory ofdipole-dipole non-radiative, we calculate that the distance r between the donor and acceptor is less than 7 nm and the non-radiative energy transfers within molecule.4. The conformation of gelatin protein were studied using synchronousfluorescence spectra and fluorescence spectra of three-dimensional. The resultsshow that the nano-Fe₂S₃ and nano-CoS change the micro-environment of gelatinprotein, in which when the nanoparticles increase to a certain concentration, thefluorescence of gelatin protein will be completely quenched. It indicates that thestructure of gelatin protein is almost destroyed completely, which is an evidencethat Nano-Fe₂S₃ and Nano-CoS can create great influence on the structure ofprotein.