Purification method

Method of isolating nucleic acid from a sample, comprising: (i) contacting a sample comprising nucleic acid with an alcohol and a salt; (ii) contacting a filter with the composition comprising nucleic acid obtained following step (i) to provide a filter having nucleic acid bonded thereto; and (iv) eluting at least a portion of the nucleic acid from the filter, wherein elution comprises incubating the filter in an elution buffer at a temperature of from 70 to 90 ºC. Optionally, between steps (ii) and (iv), step (iii) treating the filter having the nucleic acid bonded to it with a wash solution comprising alcohol. Optionally, the elution temperature is 80 ºC. Optionally, said filter can have at least a first porous region and a second porous region; the first porous region being arranged to be contacted in use by the sample before the second porous region, wherein the first porous region has a nominal pore size greater than the second porous region.