Evaluation of gel filtration resins for the removal of PCR-inhibitory substances from soils and sediments

A variety of gel filtration resins (Sephadex G200 and G150; Sepharose 6B, 4 B and 2B; Bio-Gel P100, P200; and Toyopearl HW 55, HW 65, and HW 75) were e valuated for their efficacy in removing PCR-inhibitory substances from feed lot soil DNA crude extracts using gravity-flow disposable columns. Sepharos e resins demonstrated the best properties for DNA purification when compare d to other gel filtration resins, and Sepharose 2B was the most efficient p urification resin based upon flow rate and the elution of DNA and humic aci ds from the columns. A method for purifying large solution volumes of DNA e xtract economically was also developed using low-cost disposable Disposafle x columns. Crude DNA extracts of cattle feedlot soil and aquifer sediment i mpacted by animal and human wastes were easily purified using the Disposafl ex column method regardless of whether a gentle chemical lysis or a bead mi ll homogenization DNA extraction method was employed. (C) 2001 Elsevier Sci ence B.V. All rights reserved.