| 摘要 |
<p>A sensitive method for detecting damage of DNA, e.g. resulting from exposure of living cells or whole organisms to low doses of radiation or chemicals, is described comprising: partial lysis of exposed cells to access the DNA; alkaline denaturing the DNA; after a selected interval stopping the denaturation by lowering the pH to a selected value; rendering the lysate homogeneous; adding an appropriate fluorescent dye which interacts preferentially with double-stranded DNA and measuring the resulting fluorescence. The decrease in fluorescence (compared to that before denaturation) is a measure of the rate of DNA denaturation which is directly proportional to the extent of DNA damage. Several factors, particularly the lowered pH at which the denaturation is stopped, have been found important for increased sensitivity. The method is suitable for monitoring the effect on DNA in living cells of environmental factors, drug and radiation therapy, and for toxicology studies. A kit adapted for carrying out the test method is described.</p> |
