摘要
本文为核酸碱基的表面增强拉曼光谱(SERS)系列工作的第一篇报导。文中对尿嘧啶及其5位卤代衍生物的常规和表面增强拉曼光谱进行了观察和比较。结果表明,卤素原子在尿嘧啶5位取代氢原子后,不仅影响了相关基团的振动频率和相对强度,而且随取代卤素原子的不同,还发生了尿嘧啶吸附活性部位的转移。尿嘧啶以l-位氮原子吸附于银溶胶表面,5-氟尿嘧啶和5-氯尿嘧啶部分以1位氮原子,部分以5位氟原子和5位氯原子吸附于Ag溶胶表面,而5-溴尿嘧啶则全部以5位溴原子吸附于Ag溶胶表面。这种变化趋势与被吸附部位原子和Ag原子配位能力的变化趋势一致。这一研究表明,SERS是研究分子在金属表面吸附过程的有力手段。
This is the first reporting article in our serial researching of the bases which are the compo- nents of nucleic acids. Normal Raman and surface-enhanced Raman Scattering Spectroscopy of uracil and 5-halide uracils have been obtained and compared. When the 5-H was replaced with halide atoms. the frequency and relative strength of related atoms' vibration changed. It was found that the adsorption active site of molecule changed with the change of substituting halide atoms. Uracil adsorbed on the surface of silver hydrosols with 1-N; 5-fluoro uracil and 5-chloro uracil adsorbed partly with 1-N, partly with 5-halide atoms; and 5-bromo uracil adsorbed with 5-Br completely. This change coincided with the change of chelating ability of N →Ag, F→Ag, Cl→Ag, and Br→Ag.
