Abstract: Provided is a novel two step chromatographic purification process (load and elute) for the isolation of genomic DNA. In this method the sample is loaded on the column and the genomic DNA product is eluted directly without any intermediate wash steps. This is accomplished by utilizing a restricted access resin (i.e., lid beads), which is easy to prepare and comprised of two layers with different properties with non-functional surfaces on the outer layer. The inner layer is modified with functional groups that act as ion-exchangers. Small molecules such as RNA and proteins can enter the inner part of the resin and larger genomic DNA molecules will pass through the resin. RNA and proteins are captured in the inner layer of the restricted access resin while genomic DNA is readily eluted in the flow-through.

Abstract: The invention provides an modified method for the separation of nucleic acids from cells, comprising: generating an aqueous solution containing the nucleic acid by lysing the cells with a lysis solution including SDS and salt; and separating the nucleic acids of interest from other cellular components. The improvement includes adding a non-ionic detergent in the lysis solution such that SDS is not precipitated and no heating of the solution is required prior to cellular lysis. The preferred non-ionic detergents are the polysorbate family of compound, including TWEEN® 20. Also disclosed are composition and kit for performing the modified method.