[Study on the surface-enhanced Raman spectrum of phenylalanine on silver sols]

The surface enhanced Raman scattering (SERS) of L-phenylalanine solution system was studied in the present paper. The enhancement effect is obvious. Compared to the conventional Raman spectra of solid phenylalanine, the frequency deviations of some peaks in the SERS spectra were observed, and the relative strengths of some peaks were certainly changed. The influence of three different laser sources on the intensity of SERS spectra is discussed. The 514.42 nm of laser source is the best among the 514.42, 632.81 and 785.18 nm. The intensity of SERS spectra can be changed with the concentration of L-phenylalanine. It does not benefit the formation of SERS spectra when the concentration is too high or too low. When the concentration of bottom solution is 1 x 10(-3) mol x L(-1), the enhancement effect of SERS is the strongest. The pH value of system also has obvious effect on the SERS, and when the pH value is 8, the enhancement effect of SERS is the best. It is the total influence of the pH on the coacervation of the silver sol and existent form of the phenylalanine.