Purify DNA longer than 20 base pairs with ready-to-use mini-columns containing Sephadex® G-50. Spin-50 mini-columns are hydrated with either TE buffer (10 mM Tris, 1 mM EDTA, pH 8.0) or water. Columns with TE buffer have a green color dot on the top of the tube; columns with water have a blue dot. The hydrating buffer may be replaced with another buffer if required. Columns without separating media or buffer are also available for custom applications. 100 columns per pack.