Preparative separation of the complementary strands of DNA restriction fragments by alkaline RPC-5 chromatography.

High pressure reversed phase chromatography (RPC-5) at pH 12 was used for preparative separation of the complementary strands of the smaller DNA fragments which are generated by the Hae III restriction endonuclease digestion of Col El DNA. A single high pressure RPC-5 chromatographic step at neutral pH served to purify duplex fragments 70, 172, 250 and 440 base pairs long; each of these yielded two elution peaks upon chromatography under alkaline denaturing conditions.