【作者】 肖新光；

【导师】 唐世华；

【作者基本信息】 广西民族大学 ， 应用化学， 2011， 硕士

【摘要】 目前，纳米粒子生物效应研究工作的内容主要是从生物整体水平、细胞水平、分子水平以及环境等几个层面开展开来的。分子水平上研究，能更好地解释纳米材料与生物大分子作用的本质。本文首次研究了纳米Fe₂S₃和纳米CoS与明胶蛋白质的原位相互作用，主要内容如下：1、在明胶介质中合成了水溶性纳米Fe₂S₃和纳米CoS。2、利用紫外–可见吸收光谱（UV–Vis）研究了纳米Fe₂S₃和纳米CoS原位键合作用。结果表明，粒子原位键合作用的拟合方程符合准一级反应动力学方程，并求得准一级反应的表观活化能、表观指数前因子及活化热力学参数；根据Lineweave-Burk方程计算了纳米粒子与明胶蛋白原位作用的键合常数K以及对应温度下反应的热力学参数。3、利用常规荧光光谱、同步荧光光谱和共振荧光光谱研究了纳米Fe₂S₃和纳米CoS与明胶蛋白的原位作用，实验发现在明胶溶液中纳米粒子的生成对明胶蛋白的内源荧光有较强的猝灭作用。依据Stern-Volmer方程、Scatchard方程和Van’t Hoff方程详细研究计算了纳米粒子与明胶蛋白结合的作用机制（包括荧光猝灭机理和结合常数），推测了主要作用力类型。研究同时表明，纳米粒子对明胶蛋白同步荧光光谱和共振光散射光谱的数据也可以定量计算原位作用的猝灭常数、猝灭速率常数、结合常数和热力学参数。根据F?rster的偶极-偶极非辐射能量转移原理计算了供体-受体间距离r，其值均小于7 nm，发生分子内的非辐射能量转移。4、应用同步荧光光谱和三维荧光光谱研究了纳米Fe₂S₃和纳米CoS与明胶蛋白发生反应后明胶蛋白构象的变化。结果表明，纳米Fe₂S₃和纳米CoS改变了明胶蛋白分子中荧光基团所处的微观环境，同时，当纳米粒子增加到一定浓度的时候，明胶蛋白的荧光峰被猝灭完全，此时明胶蛋白质的结构几乎完全被破坏，说明纳米Fe₂S₃和纳米CoS对蛋白质结构有很大的影响。更多还原

【Abstract】 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.更多还原