You can remove the adaptors on a LMP gel, being carefull not to frazzle your
DNA with UV. We stain the ladder first, and use this marker to enable removing
the linkers without UV. The portion of the gel containing the linkers can then
be confirmed by post-staining.
DNA for PCR can be used directly, or indeed purified purther by phenol
extractions or commerciallly available kits.