The invention relates to a process for selective, reversible adsorption of nucleic acids to a support material, which process is characterized in that (a) a nucleic acid-containing mixture having a cosmotropic salt content of at least 1 mole is contacted with said support material, whereupon the nucleic acid(s) is (are) adsorbed from said nucleic acid-containing mixture to said support material, and (b) the nucleic acid(s) bound to the support material is (are) detached from the support material by means of an aqueous solution having a salt content of no more than 1 mole.