SPECTROFLUOROMETRIC DETERMINATION OF NUCLEIC-ACIDS AS 8-HYDROXYQUINOLINE YTTRIUM TERNARY COMPLEXES/

The formation of nucleic acids/8-hydroxy-quinoline/yttrium(III) ternar y complexes and their fluorescent properties have been studied. The nu cleic acids studied include native and thermally denatured calf thymus DNA, fish sperm DNA and yeast RNA. In the range of pH 7.6-8.5, contro lled by NH3-NH4Cl buffer, ternary complexes are formed that fluoresce at different wavelengths with different nucleic acids. Based on the fl uorescence reactions, sensitive spectro-fluorimetric methods for nucle ic acids are proposed. In optimal conditions, the calibration curves w ere linear in the range 0.5-4.0 mu g ml(-1) for calf thymus DNA, 0.5-2 .5 mu g ml(-1) for fish sperm DNA and 0.5-4.0 mu g ml(-1) for yeast RN A. The limits of determination (3 sigma) were 0.030 mu g ml(-1) for ca lf thymus DNA, 0.020 mu g ml(-1) for fish sperm DNA and 0.090 mu g ml( -1) for yeast RNA. Corresponding to the interferences of coexisting su bstances, six synthetic samples were constructed and the results of de termination were satisfactory.