NICK columns were developed for the purification of nick-translated DNA fragments but are also suitable for separation of any labeled probe from unincorporated labeled nucleotides.

• For rapid purification of labeled DNA (20 bases in length) from unincorporated radiolabeled nucleotides using gravity-flow chromatography
• Can accommodate sample volumes up to 100 μl
• Prepacked with Sephadex G-50 DNA Grade in distilled water with 0.15% Kathon CG/ICP Biocide

They are ready for immediate use, and operate by gravity flow. Tests show that at least 97% of radioactivity applied in a nick-translated mixture elutes in two well-separated peaks, corresponding to labeled DNA and unincorporated nucleotides, respectively. At least 90% of the applied DNA is recovered.