Ratiometric SERS Assays for Reliable and Automatic Quantification of Nucleic Acids

A novel ratiometric assay was developed for the accurate and facile quantification of nucleic acids using a combination of surface-enhanced Raman scattering (SERS) and two kinds of bioorthogonal Raman reporters attached to SERS probes. Normalization of the SERS intensities of a phenylethynylphenyl group by ethynylphenyl group allows the facile and automatic quantification of target DNA down to 86 pM. A novel ratiometric surface-enhanced Raman scattering (SERS) assay was developed for accurate and facile quantification of nucleic acids using two kind of bioorthogonal Raman reporters (N-(4-ethynylphenyl)-3-mercaptopropanamide (EP) as an internal standard and 3-mercapto-N-[4-(2-phenylethynyl)phenyl]propenamide (PEP) as a target DNA responsive reporter). Normalization of SERS intensities allows the accurate quantification of targeted DNA down to 86 pM.