METHODS FOR RECOVERING NUCLEIC-ACID FRAGMENTS FROM AGAROSE GELS

Agarose gel electrophoresis is a powerful technique for the separation of nucleic acids on the basis of their size and conformation. The dev elopment of methods to recover size-fractionated nucleic acids molecul es from agarose gels has greatly facilitated recombinant DNA technolog ies. Although several methods for recovering DNA and RNA molecules hav e been developed during the past fifteen years, none of them has been universally accepted. In this review we describe, discuss and evaluate the most common procedures with which we have had experience. Our eva luation is based on the criteria of yield, purity, speed, simplicity a nd low cost. We have considered three different approaches to the prob lem of recovering nucleic acids: chemical gel dissolution, physical ge l disruption and physical extrusion from intact gels.