The peristaltic pump collar accessory permits large volumes of dilute samples to be continuously loaded on to the columns without the need of a centrifuge. Residence times between the target protein and the resin matrix can be closely controlled using a peristaltic pump. Higher recoveries are obtained with slower sample loading flow rates. On a per ml sample volume basis, the peristaltic pump allows faster sample loading rates than spin columns. Typical flow rates between 1-10 ml/min are observed. Up to 1,000 fold concentration of the purified protein or antibody can be recovered in the final eluate.