His GraviTrap 1 ml pre-packed columns purify proteins for use in functional and structural genomics and proteomics research. The columns purify histidine-tagged proteins from clarified or unclarified samples without the need for a pump or purification system. Protein binding capacity is approx.40 mg/column. Separations are completed in as little as 20 min, large sample volumes can easily be applied, and concentrated purified protein elutes in a small volume. Accessories include a His Buffer Kit and the LabMate reservoir, which enables sample volumes up to 35 ml to be loaded in one run. The columns are pre-packed with Ni Sepharose 6 Fast Flow. Purifications can be performed under either native or denaturing conditions using a range of detergents, reducing agents and other additives. Nickel ion leakage is negligible, which minimizes protein precipitation and increases the yield of pure and active material.