WO2023152660A1

WO2023152660A1 - Method of packing a chromatography column system

Info

Publication number: WO2023152660A1
Application number: PCT/IB2023/051131
Authority: WO
Inventors: Marcellus Johannes Hubertus Raedts
Original assignee: Jemp Holding Bv
Priority date: 2022-02-08
Filing date: 2023-02-08
Publication date: 2023-08-17
Also published as: NL2030851B1

Abstract

A chromatography column system including a chromatography column and a slurry vessel, a pump means for pumping a slurry containing chromatography media from the slurry vessel to the chromatography column to effect packing of the chromatography column and a transport means to transport excess liquid output from the chromatography column during packing back to the slurry vessel.

Description

Method of packing a chromatography column system.

The present invention relates to the field of capturing a product present in a process liquid using a column (e.g. radial flow type or axial flow type) for liquid chromatography comprising a packed bed of beads. In particular the invention relates to the field of downstream processing processing, fractionation, separation, isolation or purification of solutes. Solutes may be biologies from cell culture, cell fermentation harvests, or separating out a fraction from human blood or ingredients from the pharmaceutical production, cosmetics production or food and beverage production.

General and specific background about chromatography are provided by US4627918A, US4676898A, US5466377A, W02014 / 092636, WO03059488, WO2007/136247 and WO2019/143251. Background about packing a chromatography column is disclosed in, i.a., GB2344543A.

Liquid chromatography often uses a separation column. The separation column contains a stationary phase, i.e. packed bed or matrix medium or material (e.g. the "gel") , which interacts with the various components of the sample fluid to be separated. The composition of the separating medium (e.g. the gel) depends on the fluid being directed there through so as to produce the desired separation.

As used herein, the terms "horizontal" or "radial flow mode", which are used interchangeably, are defined as flow of the sample (e.g. biomolecules) or eluant or wash fluid through the chromatographic column in a direction that is perpendicular to the longitudinal axis of the column, regardless of the position of the column relative to the work bench or support stands or other equipment used to support or stack the columns .

Installing the packed bed, i.e. the gel of beads, is complicated. Since the beads typically are extremely expensive (in the order of eurol-20/millilitre) , at least for industrial application, the packed bed should be treated carefully.

BACKGROUND SPECIFIC TO THE PRESENT INVENTION

The material for the packed bed is called "gel" in here and synonyms are e.g. "adsorbent" or "sorbent" or "resin" or "matrix" or "chromatography media". The beads of the gel can be small or large in diameter, e.g. beads having a diameter between 10 and 1100 micrometre (0.01-1.1 millimetre) , e.g. having a diameter of 20-100 or 100-300 or 300-500 or 500-800 or 800-1100 micrometre (equals 0.02-0.1 or 0.1-0.3 or 0.3-0.5 or 0.5-0.8 or 0.8-1.1 millimetre, respectively) .

The invention is particularly directed to a process of packing, i.e. providing the column with a packed bed of beads, to provide a packed bed chromatography column for packed bed column chromatography. This type of packing process is also known as "flow-packing"

The object of the invention is one or more of: the complete freedom of the choice of packing liquid that best suits the performance of the flow packing and/or the flow velocity to support proper bed compression; to minimize the volume of liquid required to create the slurry; to reduce the over-all time required to form an efficient packed bed with optimal bed compression. A reason for time reduction could be the prevention of any loss of chromatography related activity of the beads.

The bed materials can vary enourmously, some are soft, sponge-like, some are hard like glass or aluminum oxide, some are made of synthetic polymeres like acrylic or styrene. The physical form or shape combined with the density of the beads determine the conditions for flow-packing. More fragile or soft generally means more gentle, more rigid dense and strong or very porous, typically means a more aggressive flow-packing approach. Also surface modifications of the beads play a role in that the surface modification can cause individual beads to repell. To achieve the correct bed compression, density and the composition of the packing liquid, the flow velocity and the duration of the flow packing are the main parameters to reach the proper result.

During the packing procedure, the gel is added to the bed space of the column as a slurry, contained within a slurry vessel . In particular, the slurry is a mixture of beads and packing liquid. For example, the gel is dispensed into the slurry vessel and packing liquid is added to and mixed with the gel within the slurry ves sel . Preferably the packing liquid in the slurry provides that the gel is free flowing in a homogeneously mixed state within the slurry ves sel .

From the slurry ves sel , the slurry is pumped into the bed space of the column to pack the column and the beads are retained within the column while exces s liquid, obtained from the slurry, is removed from the column and returned to the slurry ves sel .

The slurry completely fills the bed space within the column and continued feeding of slurry to the column causes the exit from the column of exhaust flow of liquid from the slurry while the beads present in the slurry are retained by the porous walls ( a synonym is "boundaries" ) of the bed space . As this proces s proceeds the packed bed forms against the porous walls of the bed space and packing is complete when the bed space is completely filled by the beads from the slurry . Typically, the flow rate of the feed flow and/or the exhaust flow reduces to zero if the bed space is completely filled by the beads from the slurry since the beads become blocked at that time .

The exhaust flow is for at least 80 % or 90 % , preferably completely, kept in the closed circulation between the slurry ves sel and the column . Thus , the exhaust flow is recycled, by returning part of it to the slurry ves sel and in jecting part of it into the slurry flow on it s way from the slurry ves sel to the bed space within the column . This recycling act s to dilute the beads in the slurry as packing progres ses until all the beads have been retained within the bed space . It also as sist in prevention of sedimentation of the slurry during the packing procedure . Thus , part of the exhaust flow coming from the column bypas ses the slurry ves sel and is added, as dilution flow, to, and thus dilutes , the slurry that has left the slurry ves sel and flows towards the column to be dispensed into the bed space of the column .

By application of the dilution flow, as the invention proposes , the packing procedure is made more reliable such that the time required to obtain a correctly packed bed is reduced .

Preferably, a flow channel extends from the column to the slurry ves sel , to transport the exhaust flow from the column to the slurry vessel. A bypass channel connects to this flow channel, to bypass part of the exhaust flow. This bypass channel is preferably provided with a flow treatment device, e.g. flow splitter, designed to prevent that gas or air, e.g. as bubbles, remains in the bypass flow (i.e. the dilution flow) . Such flow treatment device could be like a bubble trap or functionally equivalent object to remove gas or air from the bypass flow. A feed channel extends from the slurry vessel to the column, to transport the slurry from the slurry vessel to the column. The feed channel is provided with a pump means to pump the slurry towards the column. The bypass channel connects to the feed channel, preferably upstream from the pump means. This assembly of channels preferably is provided with at least one or two controlled components, e.g. control means to control the flow through the channels, e.g. to control one or more of the operation of the pump means (e.g. by the application of one or more sensors, e.g. one or more of a flow meter, pressure meter or slurry density meter in e.g. the feed channel, preferably downstream from the pump means) ; the amount of flow through the bypass channel (e.g. by the application of a controlled valve and/or a sensor, e.g. a flow meter, in the bypass channel) . Preferably such sensor is connected to an actuator, e.g. pump means or controlled valve to control the behaviour of said actuator.

A channel is e.g. a pipe or tube. The flow is preferably controlled such that the dilution flow is controlled, e.g. by a controlled valve, and/or the flow of slurry (i.e. the feed flow) is controlled by a controlled pump means and/or controlled valve, preferably downstream from the location where the dilution flow is injected into the feed flow.

The slurry vessel is preferably provided with a mixer. A drive shaft is part of the mixer and carries at low level mixing blades (also called "vanes") . The drive shaft is preferably located at the axial vessel centre. Preferably, the upper longitudinal end of the drive shaft is outside the vessel and/or attached to a drive means, e.g. electric motor, to bring the drive shaft, and thus the associated mixing blades, in rotation to stir the liquid inside the vessel.

Special requirements of the column and slurry vessel and related components in a pharmaceutical production environment is the "sanitary design" of such solution. Accepted sanitary design solutions minimize chances for microbial growth "by design" and offer effective clean-ability for all areas that could create a danger for microbial growth. Materials that are applied need to be protected or resistant to corrosion, aggressive liquids and should by-design minimize the application of any kind of external add-on which can and will create a conflict with respect to a risk of microbial growth.

A sanitary solution is e.g. a, preferably electro, polished surface, preferably mirror polished. To offer the best possible sanitary design such surface is provided in high grade stainless steel, e.g. one of: 1.4403, 1.4404, 1.4435, 1.4539, 1.4462, 304 (L) 316 (L) , 904 (L) , Duplex.

Alternatively a plastic container or disposable sanitary plastic bag-lined container will be suitable as slurry vessel provided sufficient mixing is ensured and the inlet/outlet connections support the flow rates required.

A liquid chromatography column of radial type preferably comprises: a housing, of cylindrical shape, defining a chamber therein and including a, preferably removable, axial end plate of circular shape; a first (also named: "outer") and second (also named: "inner") porous frits or membranes of cylindrical shape, these frits are mutually spaced and delimit the bed space; a bed or packing of particulate chromatographic separation material positioned intermediate said porous frits inside the bed space and thus having a torus shape; optionally an axially extending core element and located inside the inner frit. The axially extending cylindrical external housing wall, first and second frit and core are coaxial.

The torus shaped packed bed allows the radial flow of process liquid through the column.

This invention is applicable to columns of small dimension, e.g. 3 millilitre and also large dimension, e.g. 1.000 litre. The flow rate of the slurry from the slurry vessel towards the column is preferably at least 1 or 50 or 100 millilitre/minute or 1 or 10 or 100 or 1000 lit re/minute .

NON-LIMITING EXAMPLES

The accompanying drawings, which are incorporated and form a part of the specification, illustrate in fig. 1-12 different embodiments of the invention and, together with the description, serve to explain the principles of the invention. The drawing shows flow circuits wherein flow channels interconnect the components such as the slurry vessel and the column, such that the liquid can flow through the flow channels and the components .

Fig. 1-3 and 6-9 show embodiments for a radial flow type column. Fig. 4-5 and 10-11 show embodiments for an axial flow type column.

Meaning of reference signs: 1 slurry vessel; 2 pressure gauge; AFC axial flow type column; RFC radial flow type column; N1 valve, e.g. packing valve; N2 valve, e.g. process valve; N3 valve, e.g. process valve; N4 valve, e.g. additional valve or multi position valve or T-valve; N5 valve; N5 or N6 slurry vessel valve; N7 or N8 proportional valve regulated; Pl packing pump regulated; P2 dilution pump regulated; FS flow splitter; PM packing manifold; arrow (drawn in continuous line) flow direction .

The measures disclosed herein can be taken together individually in any other conceivable combination and permutation to provide an alternative to the invention. Included are also technical equivalents and genuses or generalizations of the revealed measures. A measure of an example is also generally applicable within the scope of the invention. A measure disclosed herein, for example of an example, can be readily generalized for inclusion in a general definition of the invention, for example to be found in a patent claim .

Claims

1 . Method of filling a chromatography column with a chromatography medium to equip the chromatography column with a packed bed of chromatography beads for providing a packed bed chromatography column, wherein a slurry is prepared comprising a mixture of a liquid and the chromatography medium , in which, prior to filling the chromatography column, it is ensured that the slurry is prepared and that the prepared slurry is contained in a slurry ves sel so that a stock of slurry separated from the chromatography column is created and is contained in the slurry ves sel , and during the filling of the chromatography column with chromatography medium a pumping arrangement is used to pump slurry containing the chromatography medium from the slurry ves sel through a feed channel preferably containing the pumping means to the chromatography column to ensure filling of the chromatography column with chromatography medium, wherein during filling the chromatography column with chromatography medium, care is taken to ensure that the chromatography medium contained in the slurry remains in the chromatography column as the liquid of the slurry flows out of the chromatography column and into a discharge channel and flows through the discharge channel during filling of the chromatography column and is returned to the slurry ves sel for mixing in the slurry ves sel with the slurry present in the slurry ves sel , while part of the liquid flowing through the di scharge channel is branched of f through a branch channel from the discharge channel upstream of the slurry ves sel and through the branch channel is supplied to and introduced into the feed channel in that the branch channel is connected, preferably directly, to the feed channel so that the slurry inside the feed channel is diluted by liquid, which may be called " diluent liquid" , coming from the chromatography column during filling, so that the liquid leaving the chromatography column during the filling of the chromatography column with a chromatography medium is kept in closed circulation by returning a first part thereof to the slurry ves sel and mixing it in the slurry ves sel with the slurry contained therein and a second part thereof to be fed via the branch channel to the feed channel , which second part bypas ses the slurry ves sel and mixes as dilution liquid with the slurry located inside the feed channel .

2 . Method according to claim 1 , wherein the branch channel is equipped with a liquid treatment device , e . g . flow splitter, which is adapted to prevent gas being present in the branch flow resp . dilution stream, and which liquid treatment device removes gas bubbles present in the branch liquid from the branch liquid .

3 . Method according to claim 1 or 2 , wherein the branch channel connect s to the supply channel upstream of the pumping facility, so that the branch liquid is metered from the branch channel into the supply channel and then flows downstream through the supply channel and then pas ses the pumping facility on it s way to the chromatography column .

4 . Method according to claim 1 , 2 or 3 , wherein at least one controlled component is used to control the flow through one or more of the supply channel , exhaust channel , branch channel , preferably wherein the number of controlled component s is a minimum of two .

5 . Method according to claim 4 , wherein the one or more controlled component s comprise a controller ; and/or wherein the operation of the pumping facility is controlled with the controlled component and/or the control means .

6 . Method according to any of claims 4 or 5 , wherein one or more of a flow meter, pres sure meter or density meter is used to measure the slurry in the feed channel to control the operation of the pumping facility; and/or wherein said measurement is performed downstream of the pumping facility .

7 . Method according to any of claims 4- 6 , wherein the magnitude of the flow through the branch channel is controlled; and/or wherein a controlled valve is provided on the branch channel to thereby control fluid flow therethrough .

8 . Method according to any of claims 4-7 , wherein a sensor, such as a flow meter, is applied to the branch channel to thereby control the flow of liquid therethrough and preferably wherein said sensor is connected to an actuator, such as a pumping device , for controlling the behavior of that actuator .

9 . Method according to any of the preceding claims , wherein the flow is controlled so that the branch flow is controlled; and/or wherein the flow is controlled by a controlled valve .

10 . Method according to any of the preceding claims , wherein the flow is controlled so as to regulate the slurry flow in the feed channel ; and/or wherein the flow is controlled by a controlled pumping facility .

11 . Method according to any of the preceding claims wherein the flow is controlled by a controlled valve ; and/or wherein the control of the slurry flow takes place downstream of the location where the branch liquid i s introduced into the feed stream .

12 . Chromatography column system comprising a chromatography column and a slurry ves sel , a pumping arrangement , a feed channel , a discharge channel and a branch channel branching from the discharge channel and branching onto the feed channel , adapted to carry out the method of any one of claims 1-11 .

13 . System according to claim 12 , de signed such that during filling of the chromatography column the liquid of the slurry flows out of the chromatography column and into a discharge channel and flowing through the discharge channel to be returned to the slurry ves sel for mixing in the slurry ves sel with the slurry present in the slurry ves sel , wherein part of the liquid coming from the chromatography column and flowing through the discharge channel is branched of f through a branch channel from the discharge channel upstream of the slurry ves sel and through the branch channel is supplied to and introduced into the feed channel in that the branch channel is connected, preferably directly, to the feed channel so that the slurry inside the feed channel is diluted by liquid, which may be called " diluent liquid" , coming from the chromatography column during filling, so that that the liquid leaving the chromatography column during the filling of the chromatography column with a chromatography medium is kept in closed circulation by returning a first part thereof to the slurry ves sel and mixing it in the slurry ves sel with the slurry contained therein and a second part thereof to be fed via the branch channel to the feed channel , which second part bypas ses the slurry ves sel and mixes as dilution liquid with the slurry located inside the feed channel .