An optimal method of DNA silver staining in polyacrylamide gels.

DNA silver staining has widely been used to detect DNA fragments in polyacrylamide gels with high sensitivity. We developed an optimal method for DNA silver staining on polyacrylamide gels. The novel procedure can be completed within 10 min instead of over 20 min with the conventional methods. The sensitivity is significantly improved by the silver-ion sensitizer (Eriochrome black T (EBT)) and the minimum of 0.11 and 1.75 ng of DNA amount can be detected in denaturing and nondenaturing polyacrylamide gel, respectively. Compared with the conventional silver staining methods, the improved optimal method can save time and display high sensitivity, color uniformity, and long storage time of the staining gels.