Abstract: A method of isolating target nucleic acid molecules from a solution comprising a mixture of different size nucleic acid molecules, in the presence or absence of other biomolecules, by selectively facilitating the adsorption of a particular species of nucleic acid molecule to the functional group-coated surface of magnetically responsive paramagnetic microparticles is disclosed. Separation is accomplished by manipulating the ionic strength and polyalkylene glycol concentration of the solution to selectively precipitate, and reversibly adsorb, the target species of nucleic acid molecule, characterized by a particular molecular size, to paramagnetic microparticles, the surfaces of which act as a bioaffinity adsorbent for the nucleic acids. The target nucleic acid is isolated from the starting mixture based on molecular size and through the removal of magnetic beads to which the target nucleic acid molecules have been adsorbed.

Abstract: Described herein is a method in which genomic nucleic acid of a cell can be separated from nucleic acid having a molecular weight that is lower than the molecular weight of the genomic nucleic acid (e.g., plasmid DNA) of the cell directly from a cell growth culture. Also described herein, a method in which genomic nucleic acid can be separated from nucleic acid having a molecular weight that is lower than the molecular weight of the genomic nucleic acid in a cell lysate without the need to prepare a cleared lysate.

Abstract: A method of isolating target nucleic acid molecules from a solution comprising a mixture of different size nucleic acid molecules, in the presence or absence of other biomolecules, by selectively facilitating the adsorption of a particular species of nucleic acid molecule to the functional group-coated surface of magnetically responsive paramagnetic microparticles is disclosed. Separation is accomplished by manipulating the ionic strength and polyalkylene glycol concentration of the solution to selectively precipitate, and reversibly adsorb, the target species of nucleic acid molecule, characterized by a particular molecular size, to paramagnetic microparticles, the surfaces of which act as a bioaffinity adsorbent for the nucleic acids. The target nucleic acid is isolated from the starting mixture based on molecular size and through the removal of magnetic beads to which the target nucleic acid molecules have been adsorbed.