Learn how to use this product The Strep-Tactin®XT 4Flow®, high capacity FPLC column, contains 4% agarose resin coupled to Strep‑Tactin®XT. The columns can be used for fully automated purification of Strep-tag®II or Twin-Strep-tag® fusion proteins with HPLC/FPLC devices, like Äkta®. The resin is suitable for all protein classes, especially low-abundant or challenging proteins. The low agarose concentration is suitable for the purification of targets with high molecular weights. Compared to Strep-Tactin® 4Flow® resin, this high-capacity variant has a higher density of Strep-Tactin®XT, resulting in twice as much purified protein. The resin has broad pH compatibility, excellent pressure stability, strong binding affinity, and delivers high target purity (> 95 %). For the purification of multimeric proteins, we recommend using Strep-Tactin® Superflow® high capacity FPLC columns since the increased avidity might influence elution efficiency. It should be noted that this product was previously called Strep-Tactin®XT 4Flow® high capacity cartridge.