SERS spectra of TvNPV-VP influenced by the pH value of Ag hydrosols

Trabala vishnou Nuclear Polyhedrosis Virus (TvNPV) is one kind of insect virus. It was found first in Chengdu arear of south west China. The surface-Enhanced Raman Scattering (SERS) spectra of virion protein of TvNPV (TvNPV-VP) adsorbed on the silver surface and the SERS spectra influenced by the pH value of silver hydrosols have been obtained and analysed. In the SERS spectra of TvNPV-VP, pH value of the silver hydrosols are pH4 (a), pH6 (b) and pH10 (c). The bands due to t (NH 2 ) are 1176 cm -1 (a), 1174 cm' (b), 1176 cm -1 (c). The band due to υ (NH 2 ) are 1258cm -1 (a), 1256cm -1 (b), 1252cm -1 (c). The bands due to 6 (NH 2 ) are 1620cm -1 (a), 1630cm -1 (b), 1634cm -1 (c). All the vibrations of amino groups are stronger In low pH silver sols than that of in higher pH silver sols. The band due to υ (COO-) are 470 cm -1 (a), 460 cm -1 (b); the band due to w(COO - ) is 577 cm -1 (c). The band due to υ (C-COO - ) are 928cm -1 (b), 931cm -1 (c). The band due to υ s (COO - ) are 1390cm -1 (a), 1390cm -1 (b). The bands due to υ a (COO - ) are 1594 cm -1 (a), 1592 cm -1 (b). More vibrations of carboxylate groups are stronger in higher pH silver hydrosols than that of in lower pH conditions. It shows that the distance between amino groups and surface and the geometry of amino groups on Ag surface are influenced by the pH value of silver hydrosols.