Ji Yun-Tao, Qu Chang-Qing, Cao Bin-Yun
College of Animal Science and Technology, Northwest A&F University, Shaanxi, PR China.
Electrophoresis. 2007 Apr;28(8):1173-5. doi: 10.1002/elps.200600557.
A silver staining technique has widely been used to detect DNA fragments with high sensitivity on polyacrylamide gels. The conventional procedure of the silver staining is tedious, which takes about 40-60 min and needs five or six kinds of chemicals and four kinds of solutions. Although our previous improved method reduced several steps, it still needed six kinds of chemicals. The objective of this study was to improve further the existing procedures and develop an optimal method for DNA silver staining on polyacrylamide gels. The novel procedure could be completed with only four chemicals and two solutions within 20 min. The steps of ethanol, acetic acid, and nitric acid precession before silver impregnation have been eliminated and the minimal AgNO3 dose has been used in this up-to-date method. The polyacrylamide gel of the DNA silver staining displayed a golden yellow and transparent background with high sensitivity. The minimum 0.44 and 3.5 ng of DNA amount could be detected in denaturing and nondenaturing polyacrylamide gel, respectively. This result indicated that our optimal method can save time and cost, and still keep a high sensitivity for DNA staining in polyacrylamide gels.
一种银染技术已被广泛用于在聚丙烯酰胺凝胶上高灵敏度地检测DNA片段。传统的银染程序很繁琐，大约需要40 - 60分钟，需要五六种化学试剂和四种溶液。尽管我们之前的改进方法减少了几个步骤，但仍需要六种化学试剂。本研究的目的是进一步改进现有程序，开发一种用于聚丙烯酰胺凝胶DNA银染的最佳方法。新程序仅用四种化学试剂和两种溶液即可在20分钟内完成。在这种最新方法中，省去了银浸渍前的乙醇、乙酸和硝酸处理步骤，并使用了最小剂量的硝酸银。DNA银染的聚丙烯酰胺凝胶呈现金黄色且背景透明，灵敏度高。在变性和非变性聚丙烯酰胺凝胶中分别可检测到的最小DNA量为0.44 ng和3.5 ng。这一结果表明，我们的最佳方法可以节省时间和成本，并且在聚丙烯酰胺凝胶中对DNA染色仍保持高灵敏度。
