A system and method for manipulating magnetically responsive particles in a solution to separate nucleic acid molecules from cell components in a cell solution. The system and method employ a device capable of receiving a plurality of tubes, each of which contain respective sample and magnetically responsive particles. The device includes heating and cooling devices to facilitate a lysing step to release the nucleic acid molecules from the cells in the cell solution. The device further includes moveable magnets which can be moved proximate to and away from the tube to hold the magnetically responsive particles to which the nucleic acid molecules become bound, so that the molecule-bound particles can be separated from the remainder of the solution, and washed as appropriate. The system also employs an electromagnet which is capable of demagnetizing the particles to allow the particles to freely mix with solution, such as elution solutions which are used to unbind the molecules from the particles.