摘要
利用荧光光谱和紫外-可见吸收光谱研究了pH=12.0及不同温度下,水溶性硫化镉纳米晶与明胶结合反应的光谱行为,实验发现在明胶溶液中硫化镉的生成对明胶的内源荧光有较强的猝灭作用。用Lineweave-Burk方程处理实验数据,发现硫化镉与明胶发生反应生成了配合物,结合红外和紫外-可见吸收光谱结果,属于静态荧光猝灭;计算了不同温度下反应的结合常数K(285K:1.07×104L/mol;292K:9.69×103L/mol;299K:8.06×103L/mol)及对应温度下结合反应的热力学参数(ΔH=-14.18kJ/mol;ΔG=-21.98/-22.28/-22.36kJ/mol;ΔS=27.36/27.74/27.36J/(K?mol),证明二者主要靠静电作用力结合。根据F?rster的偶极-偶极非辐射能量转移原理计算出结合位置距离色氨酸残基4.09nm,发生分子内的非辐射能量转移,为探讨纳米颗粒与此类生物大分子之间相互作用的化学机制提供了重要的信息。
The interaction between water-soluble CdS and gelatin in aqueous solution was explored using fluorescence, infrared （IR） and UV-Vis spectra at pH 12.0 and different temperatures. Results show that the formed complex had a strong ability to quench the fluorescence launched from gelatin. The fluorescence quenching data were analyzed according to Lineweave-Burk double-reciprocal equation and the gelatin had reacted with CdS to form a complex. This kind of static fluorescence quenching goes with non-radiation energy transfer happening within single molecule. According to Lineweave-Burk equation, K（ 285 K： 1.07× 10^4 L/reel; 292 K： 9.69×10^3 L/mol; 299 K： 8.06× 10^3 L/mol）, the formation constants of the compound at different temperatures and the thermodynamic parameters （△H = 14.18 k J/mol; △G = 21.98/-22.28/ 22.36 k J/mol; △S = 27.36/27.74/27.36 J/K·mol） at certain temperatures were obtained, indicating that the binding force between them is mainly the static in nature. The binding locality was an area of 4.09 nm away from tryptophan residue in gelatin based on Forster＇s non-radiation energy transfer mechanism. The results provide information for exploring the chemical mechanism of interaction between nanoparticle and this kind of biological macromolecule.
出处
《中国组织工程研究与临床康复》
CAS
CSCD
北大核心
2009年第38期7587-7592,共6页
Journal of Clinical Rehabilitative Tissue Engineering Research
基金
the Natural Science Foundation of Guangxi Zhuang Autonomous Region, No.0991083~~
