Metallic nanoparticles as SERS agents for biomolecular imaging

Raman spectroscopy is a promising technique for the identification and analysis of molecules in a sample without any labeling or modification. Since Raman scattering spectra provide information about intracellular molecular distributions, metabolism and chemical reactions, Raman microscopy has been widely utilized for bio-imaging and biofunctional analysis. By using metallic nanostructures, Raman scattering from molecules at the vicinity of a metal surface is significantly enhanced, which is called surface-enhanced Raman scattering (SERS). Due to localized field enhancement, the highly sensitive detection of molecules can be achieved and many attempts to apply it for biological and biomedical research have been made. In this article, we review the applications of metallic nanoparticles as SERS agents for molecular analysis and imaging of biological cells and tissues.