Measurement of nucleic acid concentrations using the DyNA Quant and the GeneQuant

Molecular biology is now a routine tool in almost all biological research fields. With the exponential growth in the number of molecular biological techniques, there is a recognizable need for sensitive, accurate and precise quantitation of nucleic acids. We present here two complementary instruments designed for the quantitation of nucleic acids, the GeneQuant II and the DyNA Quant 200 Fluorometer. The GeneQuant II can rapidly determine the UV absorbance of a solution and display the calculated DNA, RNA or protein concentration. In addition, the GeneQuant can display calculated melting temperatures for a given DNA oligonucleotide base sequence, a useful feature for primer design. The DyNA Quant 200 quantitates DNA on the basis of the fluorescent Hoechst 33258 dye/double-stranded (ds)DNA assay. Upon binding to dsDNA, the spectral properties of the dye change such that it becomes highly fluorescent at 460 nm when excited at 365 nm. The assay has proven to be a specific and sensitive alternative method for DNA quantitation, particularly for unpurified DNA samples. Together, the GeneQuant II and the DyNA Quant 200 are a cost-effective and convenient solution to the routine protein and nucleic acid quantification needs of the molecular biologist.