this relates to filter columns for isolating nucleic acids . the filter column is adapted for stable placement within the upper portion of standard plastic collection tubes of various sizes . the body of the filter column has a number of surfaces to accommodate placement within variously sized collection tubes . the filter column contains nucleic acid - specific filter which can be located at alternate regions within the filter column , providing different filter surface areas and loading volume capacities using the same column body . the filter column has an opening on an upper end adapted to be sealed by a cap . a method for recovering nucleic acids using such filter column is also provided .