DNA measurement by mithramycin fluorescence in chromatin solubilized by heparin

✍ Scribed by André Groyer; Paul Robel

• Book ID: 102983177
• Publisher: Elsevier Science
• Year: 1980
• Tongue: English
• Weight: 509 KB
• Volume: 106
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(80)90146-3

✦ Synopsis

The mithramycin fluorescence procedure described by B. T. Hill and S. Whatley (1975, FEBS Lett., 56, 20-23) for DNA measurement tends to underestimate DNA concentrations in biological samples as compared to the results obtained by the diphenylamine reaction. This discrepancy disappears when DNA is first solubilized, by buffer containing heparin, from either cell homogenates or nuclear preparations. The optimal conditions for maximal fluorescence are 8 mM Mg 2+ 10 &ml mithramycin, and heparin to DNA ratios , 30.15 (w/w). Background fluorescence is reduced 90% by dextran-coated charcoal adsorption of unbound mithramycin. The limit of sensitivity of the assay is 0.3 &ml and fluorescence is linear up to 30 pg DNA/ml.