Development of an automatic analyzer of DNA break, based on atomic force microcopy

Abstract

We have developed a novel automated system for the quantitative evaluation of DNA damage based on an atomic force microscopy (AFM). By visualizing DNA molecules and measuring their lengths directly and automatically, we succeeded to detect the increase in DNA damage caused by several hundred Gy-irradiation with the statistical significance (p < 0.05). The result demonstrates the improvement of sensitivity by one order of magnitude compared to previously reported AFM-based systems. We found AFM more suitable for the quantitative detection of DNA break than electron microscopy, because it is easy to operate, and can be used in high throughput analysis. These results suggest that our automatic analyzer is powerful tool for the quantitative evaluation of DNA break. [J Radiat Res 44:439 (2003)]