Resonance light scattering for the determination of nucleic acids with methyl violet

For the first time, methyl violet (MV) was used to determine nucleic acids with a resonance light scattering (RLS) technique. The interactions of MV with nucleic acids give strong signals of RLS at 327.0, 490.0 and 651.0 nm. Based on this reaction, a new quantitative determination method for nucleic acids in aqueous solutions has been developed. At pH 7.51 and ionic strength 0.005 mol kg(-1), with 4.0x10(-5) mol l(-1) of MV, linear relationships were found between the enhanced intensity of RLS at 651.0 nm and the concentration of nucleic acids in the range 0-3.0 mu lg ml(-1) for herring sperm DNA (hsDNA) and calf thymus DNA (ctDNA), 0-4.0 mu lg ml(-1) for yeast RNA (yRNA). The limits of detection were 404.5 ng ml(-1).