Millipore Corporation

Emd Millipore Corporation

Atlantic Applied Research Corporation

Michael W Phillips

Wilson Moya

Mikhail Kozlov

Anthony J DiLeo

Senthilkumar Ramaswamy

Brian Gagnon

Matthew T Stone

Ajish Potty

Jad Jaber

William Cataldo

Neal A Brown

Christopher Gillespie

Alex Xenopoulos

The present invention relates to improved processes and systems for purification of biological molecules, where the processes can be performed in a continuous manner.

Purification of biological molecules

Media and devices, such as anion exchangers including such media, wherein the media is a membrane having a surface coated with a polymer such as a polyallylamine. The resulting membrane offers stronger binding of protein impurities and superior removal of host cell proteins from biological samples than conventional ligands based on quaternary ammonium salts, including trimethylammonium ligands. Also described is a chromatography scheme and method for purifying monoclonal antibodies, wherein the anion exchange sorber is placed downstream of an affinity column (such as Protein A or Protein G affinity column) and optionally one or more polishing devices such as cationic exchange columns. Little or no dilution of the cation exchanger pool (or affinity column exchange pool where no cation exchanger is used) is necessary to lower the conductivity of the sample. The sorber functions well to strongly bind host cell proteins and other impurities in biological samples even at high conductivities and pH.

Media for membrane ion exchange chromatography based on polymeric primary amines, sorption device containing that media, and chromatography scheme and purification method using the same

Media and devices, such as anion exchangers including such media, wherein the media is a membrane having a surface coated with a polymer such as a polyallylamine. The resulting membrane offers stronger binding of protein impurities and superior removal of host cell proteins from biological samples than conventional ligands based on quaternary ammonium salts, including trimethylammonium ligands. Also described is a chromatography scheme and method for purifying monoclonal antibodies, wherein the anion exchange sorber is placed downstream of an affinity column (such as Protein A or Protein G affinity column) and optionally one or more polishing devices such as cationic exchange columns. Little or no dilution of the cation exchanger pool (or affinity column exchange pool where no cation exchanger is used) is necessary to lower the conductivity of the sample. The sorber functions well to strongly bind host cell proteins and other impurities even at high conductivities and pH.

The method for determining an effective Peclet number for a membrane adsorber device includes the steps of (a) equilibrating the membrane adsorber device with an equilibration buffer at a known pH and conductivity; (b) challenging the membrane with a known concentration of a specific solute in said equilibration buffer; (c) monitoring the breakthrough of the solute downstream of the membrane as a function of a value selected from the group consisting of time, challenge volume and other suitable variable related to total quantity of material challenged to membrane adsorber device; (d) analyzing the solute breakthrough curve to determine pertinent flow characteristics of said membrane adsorber device by calculating the sharpness of the breakthrough curve of the membrane adsorber device and (e) comparing the results calculated in step (d) to results from known integral devices to determine the effective Peclet number.

Method for determining an effective peclet number for a membrane adsorber device

A filtration process and apparatus are provided wherein feed fluid to be filtered is introduced into a small gap between two rectangular plates. At least one of the plates supports a porous filtration membrane within the gap. During filtration, at least one of the plates is oscillated to effect a continuously changing gradient of gap width between opposing surfaces of the plate. A permeate is collected and a seal is provided to prevent admixture of the permeate with either feed fluid or retentate.

Vibrationally-induced dynamic membrane filtration

A process is provided for rapidly and non-destructively evaluating the solute retention characteristics of porous membranes using a novel liquid-porosimetric technique. A ratio of two membrane permeabilities is measured at preselected operating conditions using a pair of mutually immiscible fluids, one of which is employed as a membrane wetting agent and the other used as an intrusion fluid. At the first operating condition, a particular transmembrane pressure is chosen so as to intrude nearly all of the pores present in the membrane sample. At the second operating condition, a particular membrane permeability is chosen so as to achieve a specified permeability ratio. The resulting transmembrane pressure corresponding to this particular membrane permeability is compared to a previously established standard curve which permits identifying the solute retention characteristics of the porous membrane.

Process for evaluating solute retention characteristics of membranes

A process is provided for rapidly and non-destructively evaluating the particle retention characteristics of porous membranes using a novel liquid-porosimetric technique. A ratio of two membrane permeabilities is measured at preselected operating conditions using a pair of mutually immiscible fluids, one of which is employed as a membrane wetting agent and the other used as an intrusion fluid. The first operating condition, a particular transmembrane pressure, is chosen so as to selectively intrude those pores accessible to a given sized particle, such as a virus. The second operating condition, either a second preselected transmembrane pressure or a water permeability measurement, is chosen such that nearly all of the membrane pores are intruded. The ratio of the two permeabilities obtained with each set of operating conditions is thus the percentage of total flow through the membrane pores accessible to a given sized particle. By experimentally measuring this permeability ratio on membranes with known particle retention behavior, a calibration curve relating the permeability ratio to the particle retention characteristics can be constructed. From this standard correlation, the particle retention capabilities of an unchallenged membrane can be predicted in a non-destructive manner solely by measuring its permeability ratio.

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Tyngsborough, MA, United States of America

Michael W Phillips