Bio-rad Laboratories, Inc.

Mark A Snyder

Larry J Cummings

Christopher Belisle

Ken Baker

Kimberly C Brisack

Christopher Moran

A dynamic axial compression column is disclosed herein. This dynamic axial column utilized external compression to prevent the creation of end plate space in the column. The dynamic axial column can include a tube defining a first opening, a second opening, and a lumen extending there between. The dynamic axial column can include a first end plate assembly sealing the first opening and movably extending at least partially into the lumen via the first opening, a second end plate assembly sealing the second opening, a plurality of rods extending along the outside of the tube and connecting the first end plate assembly and the second end plate assembly, and a first plurality of compression devices external to the tube and engaging one of the plurality of rods to bias the first end plate assembly towards the second end plate assembly.

Dynamic axial compression for preparative columns using external compression

The present invention discloses methods of neutralizing apatite surfaces, for example during chromatography and before protein elution.

Surface neutralization of apatite

Modified Protein A, Protein G, Protein L, or Protein A/G that lacks antibody binding activity, and methods of the modified protein's use for purifying antibodies is provided.

Removal of impurities from protein A eluates

Disclosed are compositions and methods for regenerating or reducing the deterioration of an apatite solid surface during, or subsequent to, a chromatographic procedure for purifying a target molecule from a sample, by treating the apatite solid surface with a buffered calcium solution, followed by a phosphate buffered solution, followed by an alkaline hydroxide. The buffered calcium solution, phosphate buffered solution, and alkaline hydroxide can be applied subsequent to a bind and elute or flow through purification procedure. The methods provide an increase in resin mass and/or particle strength compared to prior methods.

Apatite in-situ restoration

The present invention provides methods of purifying immunoconjugates.

Purification of immunoconjugates

In an affinity-type purification, ligands dissociated from the stationary phase that would otherwise leach into the species being purified are captured by a second ligand that is also incorporated into the stationary phase, the second ligand exhibiting an affinity-type interaction with the dissociated first ligand with sufficient specificity to avoid the undesired retention by the second ligand of species from the liquid sample or source liquid other than the species sought to be purified in the affinity column.

Prevention of leaching of ligands from affinity-based purification systems

In an axial-flow preparative chromatography column that contains a piston, commonly termed an adaptor, that is lowered over the top of the resin, the ability to lower the piston in a controlled manner to minimize the chances of damage to the resin is achieved by use of an aperture either in the piston head itself or in a compound bolt that secures the upper column frit to the piston head. The aperture is closed with a removable plug during storage and use of the piston head and column. During packing of the bed, however, the plug is replaced by a graduated rod operating as a dipstick to allow the operator to determine the distance between the bottom face of the piston head and the upper surface of the column packing.

Piston movement control for preparative chromatography column

In an affinity-type purification, ligands dissociated from a packed bed that would otherwise leach into the solution containing the species being purified are captured by a second ligand that resides in a porous barrier downstream from the packed bed, the second ligand exhibiting an affinity-type interaction with the dissociated first ligand with sufficient specificity to avoid the undesired retention by the second ligand of species from the liquid sample or source liquid other than the species sought to be purified in the affinity column.

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Oakland, CA, United States of America

Mark A Snyder