琼脂糖凝胶中DNA片段的挤压回收法

A Press-recovery Method for Extraction of DNA Fragments from Agarose Gels

为了简化琼脂糖凝胶中DNA片段的回收,该文报道一种新的挤压回收法。将含有DNA片段的凝胶块放在折叠的封口膜之间,然后用一小塑料平板将凝胶块中的DNA溶液用力挤出,用移液枪把所有挤压出的DNA溶液放入effendorf管中,然后用常规的苯酚抽提法进行纯化。DNA回收率达到40-60%(w/w)。该方法简单而有效,且回收的DNA能够直接应用于酶切、连接及PCR等各种分子生物学操作。

A press-recover method for simple extrusion of DNA fragments from agarose gels was developed. Prepare a parafilm sbeet approximately 24 cm in length and 12 cm in width （24cm × 12cm） and fold it into two sheets along the cross line in the middle of the parafilm sheet （12cm × 12cm）. The gel slice containing DNA fragment of interest is excised from 1% agarose gel with a clean razor blade and placed between the two folded parafilm sheets put on a flat table. Then the solution containing DNA is squeezed from the agarose gel slice by pressing forcibly on the parafilm surface on the gel slice using a small plastie flat board. All the eloate is then transferred into a sterile eppendorf tube and extracted with equal volume of phenol, phenol/chloroform, and chloroform, respectively. The recovery rate of this method is 40% to 60% （w/w）. This method is simple and effective, and the DNA fragments isolated by this method can be used successfully in all types of subsequent molecular manipulations such as restriction enzyme digests, ligation and polymerization.