A video technique for the quantification of DNA in gels stained with ethidium bromide

We have developed a method for the comparison of quantitative differences between nucleic acid samples run on agarose gels. It is useful for the analysis of digested genomic DNA and RNA preparations, as well as for clamped homogeneous electric field gel analysis of damaged chromosomal DNA. The technique utilizes a standard color charge-coupled device video camera, a microcomputer, and commercially available software. While not as elaborate as other image analysis systems, our method is suitable for many purposes and can be set up for a relatively low cost. In principle, any system capable of recording 24-bit color scans and measuring pixel color intensity could be used.