The invention relates to methods for easily separating single stranded
nucleic acid material from double stranded nucleic acid material in a
sample containing both. By the right choice of at lease one chaotropic
agent, preferably a guanidine salt, at a selected concentration and other
suitable conditions such a chelating agents, pH and the like, it is
possible to bind double stranded material to a solid phase such as silica
particles, whereas single stranded material will not bind under those
circumstances. By separating the silica particles from the sample the
double stranded nucleic acid material is removed. It can easily be eluted
from the silica particles. In a second step the single stranded material
may be bound to a solid phase by selecting a different set of conditions.
The particles can again be separated from the sample and the single
stranded material may now be eluted. For very efficent separations, the
process may be repeated. Following the separation of the two kinds of
nucleic acid, either kind may be amplified. Methods of amplification are
provided which do not need sequence data of the material to be amplified.
In these methods a primer will be provided with an amplification motif
and a random hybridization motif.