在银溶胶中甘氨酸和甘氨酸二肽的表面增强拉曼散射

甘氨酸及Gly-Gly和Gly-L-Pro二肽的表面增强拉曼散射谱与溶液内的普通拉曼谱的对比研究表明,银胶对COO、NH_2、C-N和C-C基团的振动有明显的增强.对CH_2基团无增强.Gly-Gly的SERS与pH有关,接近中性pH值时增强效果好,在酸性和碱性溶液内效果差.在 Gly-L-Pro的SERS谱中有强的酰胺Ⅰ带,而 Gly-Gly则几乎观察不到.

SURFACE-ENHANCED RAMAN SCATTERING (SERS) OF GLYCINE AND GLYCYL DIPEPTIDES ON SILVER COLLOID

The surface -enhanced Raman (SER) spectra of glycine and Glycyl dipeptides (glycyl-glycine and glycyl -L -proline) adsorbed on Ag colloidal particles and their Raman spectra in aqueous solution were obtained and compared with each other. The results indicated that the peak intensities of polar and charge groups such as COO . NH2. CN and C-COO were strongly enhanced, and no visible enhancement was observed for apolar CH2 group. In the case of Gly -Gly, the SERS depended upon the pH of the medium used and was the strongest in neutral media. A much stronger amide I peak was shown in the SER spectra of Gly -L -Pro than Gly-Gly.