RAMAN SPECTROSCOPIC EVIDENCE FOR Z DNA IN RAD ENZYME BOUND DNA

目标是发展表面增强拉曼散射

The objective is to develop surface-enhanced Raman scattering (SERS) as an ultrasensitive analytical tool in chemistry, biology, and medicine. SERS effect combines sensitivity of the fluorescence spectroscopy with high structural information content of Raman spectroscopy, and can be used for single molecule detection and identification. Recently, we have achieved single molecule detection and identification of "non-absorbing"molecules by using specially prepared colloidal clusters and non resonant excitation. Extremely large SERS enhancement factors on the order of 1014 were obtained at near infra red excitation for aggregated colloidal silver particles. We have also demonstrated this enhancement does not involve contribution from molecular mechanisms. Because of this, the method is not only applicable to dye molecules but also to colorless molecules, thus extending the applicability to biological molecules.