System for membrane chromatography

Abstract

To summarize the invention, a chromatography system is provided. The chromatography system is configured to process a feed fluid comprising a plurality of components, wherein at least one component of the plurality of components of the feed fluid is a target component. The chromatography system comprises: a flow path comprising a plurality of fluid control components configured to control fluid flow; a stationary phase, wherein the stationary phase is at least one membrane adsorber connected to the flow path, and the stationary phase is configured to separate the target component. The flow path is configured such that harvesting of the target component is optimized.

Description

Technical Field

[0001] The following description pertains to systems used in membrane chromatography.

[0002] background

[0003] Biopharmaceutical or drug manufacturing involves the purification of solutions from which active pharmaceutical ingredients (APIs) are extracted. These solutions, also known as feedstocks, can be produced chemically or bio-organically. Feedstocks consist of multiple components that need to be separated from each other, such as one or more target components and impurities. Chromatography is a technique used to perform this separation process.

[0004] The details of a chromatographic separation process can be selected from a variety of available options, such as those involving interaction mechanisms, process type, and stationary phase. Based on the interaction mechanism, chromatography can be classified, for example, as ion exchange, hydrophobic interaction, affinity, or mixed-mode chromatography. The process type can involve aspects of the time aspect of the process execution, such as batch or continuous operation, and / or aspects involving the interaction between the target product and the separation medium in the stationary phase, such as capture, binding, and elution or flow-through. Chromatographic stationary phases are, for example, particle / resin-based, membrane-based, monolithic, and fiber-based.

[0005] The most significant difference in chromatographic steps arises from the use of kinetically and non-kinetically restricted stationary phases. Kinetically restricted stationary phases are those that typically require a residence time of more than or about 2 minutes for binding, such as resin-based stationary phases, while non-kinetically restricted stationary phases require less than 2 minutes for binding, such as membrane-based stationary phases.

[0006] Chromatographic processes typically consist of multiple cycles, each including equilibration, loading, one or more washing steps, elution, regeneration, and in-situ washing (CIP). In equilibration, the stationary phase is prepared for the loading step, in which the binding sites of the various target substances must be freely accessible. The equilibration buffer removes residues from previous steps (e.g., CIP) that negatively impact the binding properties of the stationary phase.

[0007] During loading, the feed comprising a mixture of components interacts with a stationary phase, where one or more components remain on the stationary phase while other components continue to move. For example, in a binding and elution mode, the target component should bind to the stationary phase, while the component to be separated should move through the stationary phase. An unbound component is washed away in a washing step to prevent it from being carried into the target component in the eluent during elution.

[0008] During elution, the target component is displaced from its binding sites on the stationary phase by changes in the physicochemical properties (pH, conductivity) of the stationary phase, and then collected. During regeneration, the changes in the physicochemical properties of the stationary phase environment are more pronounced than during the elution step, allowing poorly soluble impurities (e.g., lipids, dyes, DNA) to restore the stationary phase's binding capacity. To reduce bioburden and eliminate any potential contaminants remaining on the stationary phase even after the regeneration step, a CIP step is performed. This is typically done using a caustic soda solution.

[0009] The conventional chromatographic technique is column chromatography, in which the stationary phase (also known as the "separation medium") is a resin placed in a column or tube. The separation mechanism is determined by the physicochemical properties of the resin.

[0010] Two parameters that can be adjusted for column design are the column diameter and the packing height of the separation medium. These determine the volume of the stationary phase, which should be selected based on the volume of the feed to be treated, the concentration of the target component present therein, and the binding capacity of the separation medium. The stationary phase volume is selected based on influencing factors such as the cost of the separation medium relative to the processing time and / or the cost of buffer consumption, such that 2 to 20 cycles are performed to process the entire feed volume.

[0011] In particular, the filling height of the separation medium should be selected so that:

[0012] - During column passage, it compensates for any non-uniformity in the column bed and the associated reduction in separation efficiency, productivity, and resolution over the distance covered by the feed.

[0013] - The residence time required to achieve the highest possible binding capacity of the feed on the stationary phase;

[0014] - For the defined residence time and resulting flow rate, the pressure drop / back pressure of the packed separation medium must not exceed a threshold. For example, if the column is packed with a packing pressure of 3 bar, this pressure must not be exceeded during the process; otherwise, the packed bed will be compressed, and a headspace (i.e., a liquid-filled cavity between the top of the column and the over-compressed separation medium bed) will be formed in the column. This will impair the process and the separation mechanism.

[0015] The diameter of the column should be chosen so that:

[0016] - The amount of the volume of the separation medium filled, based on the filling height, minimizes the process time, wherein the binding capacity is proportional to the volume of the separation medium filled.

[0017] - The cost of the required volume of separation medium does not exceed a given threshold, depending on the process time and number of cycles.

[0018] The duration of a column chromatography cycle is typically greater than 10 minutes, and usually ranges from several hours. For example, for protein A column chromatography processing a feed containing antibodies, if the packing height is 20 cm, the column diameter is 25 cm, and the column volume is 9.8 L, one cycle would take almost four hours, as detailed in the table below:

[0019]

[0020] The volume of each step, expressed in column volume, refers to the volume of a given fluid / medium required for a given step.

[0021] An alternative to column chromatography is membrane chromatography, in which the stationary phase is provided by one or more membrane adsorbers, i.e., microporous or macroporous membranes derived from functional groups similar to those on the resin. An exemplary membrane adsorber is disclosed in European patent application EP 2274081A1.

[0022] Compared to resins, the residence time in a membrane adsorber is shorter because convection is primarily responsible for mass transfer, resulting in more efficient adsorption compared to the diffusion mechanism that dominates in resins. Therefore, the productivity of this process, i.e., the amount of product obtained per unit feed volume and per unit time (typically expressed as g / (L*h)), can be increased by more than 3 times compared to resin-based column chromatography. Furthermore, membrane chromatography utilizes the stationary phase almost entirely compared to column chromatography.

[0023] Overview

[0024] One object of the present invention is to provide a membrane chromatography system having improved process quality and efficiency, for example, by means of one or more of the following factors: the amount of target component obtained, the purity of the target component obtained, the amount of time required to carry out the process, and the amount of resources (e.g., buffer) required to carry out the process.

[0025] The achievement of this objective according to the invention is set forth in the independent claim. Further developments of the invention are the subject of the dependent claims.

[0026] According to one aspect, a chromatographic system configured to process a feed fluid comprising multiple components is provided, wherein at least one of the multiple components of the feed fluid is a target component. The chromatographic system includes:

[0027] A flow path, comprising multiple fluid control components configured to control fluid flow;

[0028] A stationary phase, wherein the stationary phase is at least one membrane adsorber connected to the flow path, and the stationary phase is configured to separate the target component;

[0029] The flow path is configured to optimize the harvesting of the target component.

[0030] The feed fluid (also called the "feed") comprises multiple components or substances, at least one of which is the target component, or objective component. The purpose of the chromatographic process is to harvest the target component, that is, to separate the target component from the other components of the feed, and then collect the target component as the product of the process.

[0031] The product is essentially composed of the target component, which means that the degree of purity, i.e., the relative amount of the target component in the total product (e.g., by weight, mass, or volume), is close to 100%, for example, greater than 99%. For example, the purity of the product is particularly important for pharmaceutical and biopharmaceutical applications.

[0032] The feed may include more than one target component to be harvested, allowing the chromatographic process to produce more than one product. Furthermore, intermediates and / or byproducts may also be obtained and collected during the chromatographic process. In some cases, different concentrations of the target component may be collected separately.

[0033] The components of the feed fluid that are not of concern (also known as “waste components”) along with other substances used in the chromatography process (such as buffer solutions) form process waste and are collected together.

[0034] For example, the feed fluid can be a solution, such as a protein-containing solution or a cell-containing solution. Examples of cell-containing solutions include vaccines or other virus-containing solutions, as well as solutions containing mammalian cells. Examples of protein-containing solutions include liquids containing therapeutic proteins (e.g., monoclonal antibodies, enzymes, hormones, etc.). In these cases, the target component can be a solute, such as a specific type of cell or a specific protein. Waste components can include DNA, salts, and host cell proteins (HCPs).

[0035] A chromatographic system includes a flow path. The flow path includes means for achieving fluid flow, such as conduits and containers for receiving, delivering, and / or containing fluid, and means for regulating fluid flow, such as valves, pumps, sensors, and filters. Therefore, the flow path specifically includes multiple fluid control components configured to control fluid flow.

[0036] A flow path connects one or more inlet points to one or more outlet points, at which one or more fluids are directed into the flow path and at which one or more fluids are released from the flow path. The flow path may include different alternative routes connecting an inlet point to an outlet point.

[0037] The direction from the inlet point to the outlet point is the forward direction of the flow path, and it is the approximate macroscopic direction of fluid flow. The statement "X is located after Y" means that in the forward direction of the fluid path, X is after Y, that is, X is closer to the outlet point and farther from the inlet point than Y. Similarly, "X is located before Y" means that in the forward direction of the fluid path, X is before Y, that is, X is closer to the inlet point and farther from the outlet point than Y.

[0038] The fluids flowing through the flow path include one or more buffer solutions, washing fluid, feed fluid (upstream of the stationary phase), and separated components of the feed fluid (downstream of the stationary phase). A buffer solution (or "buffer solution") is an aqueous solution that effectively resists and prevents large changes in pH after the addition of an acid or base. This is due to the presence of a weak acid and its conjugate base or a weak base and its conjugate acid. Different buffer solutions may be required in different steps of a chromatographic process within a cycle.

[0039] The chromatographic system includes a stationary phase. The stationary phase is part of the chromatographic system and is configured to separate a target component from waste components that are initially mixed together in the feed fluid. The feed fluid and buffer, which may be mixed with other substances (such as dilution water), represent the mobile phase. Specifically, the stationary phase separates the target component from the mobile phase, which can then be collected.

[0040] Specifically, the stationary phase is one or more membrane adsorbers. In the case of multiple membrane adsorbers, they may be stacked on top of each other and / or provided in series or parallel on two or more alternative paths of the flow path. The membrane adsorbers may, for example, adsorb a target component, which is subsequently collected by an elution device. Alternatively, the target component may be available in the flow, i.e., due to the fact that it is not adsorbed by the membrane adsorbers, while other components of the feed fluid may be adsorbed.

[0041] Membrane adsorbers can be made, for example, of stable reinforced cellulose with sulfonic acid or salt-resistant anion exchangers or phenyl groups as ligands. Other materials can be used in membrane adsorbers, and other substances can be used as ligands. Membrane adsorbers can be provided in capsules or frames made, for example, of plastic.

[0042] The at least one membrane adsorber is connected to the flow path. When connected to the flow path, the membrane adsorber becomes part of the flow path, meaning that fluid can flow through the membrane adsorber. Exemplarily, the membrane adsorber can be connected to the flow path via a valve referred to as a "membrane valve." For example, a membrane adsorber (or a cluster of membrane adsorbers) can be connected to the flow path via a pair of membrane valves, one positioned before the membrane adsorber and the other positioned after the membrane adsorber. In this case, the flow path can include a line through the membrane adsorber and an alternative line that does not pass through the membrane adsorber. Alternatively, the membrane adsorber can be directly connected (i.e., without a valve) to a pipe or other delivery device in the flow path, and there may be only one line passing through the membrane adsorber.

[0043] Compared to column chromatography using an equal volume of stationary phase, using a membrane adsorber as the stationary phase in a chromatographic system allows for a wider operating flow rate range. For example, the operating flow rate range of the resin can be 0.05-2 CV / min, more preferably 0.1-1 CV / min, and most preferably 0.1-0.5 CV / min, while the operating flow rate range of the membrane adsorber can be 0.5-40 MV / min, more preferably 1-30 MV / min, and most preferably 3-20 MV / min.

[0044] The flow path of the chromatographic system is configured to optimize the harvesting of target components by the membrane adsorber. The flow path, particularly its fluid control components, is adapted to the operation of the membrane adsorber. In other words, the kinetics of the fluid control within the flow path are adapted to the highly dynamic properties / behavior of the membrane adsorber. Specifically, the construction / structural design of the flow path and / or the control of the fluid flow performed by the flow path are optimally configured for membrane chromatography.

[0045] The chromatography system may include or be configured to connect to a control system, such as a processor, which is configured to manage fluid control components, such as a distributed control system. The control system may receive signals from one or more fluid control components (e.g., sensors) and may send signals to one or more fluid control components, such as valves and pumps.

[0046] In a particular instance, the plurality of fluid control components may include:

[0047] A first outlet valve, connected to the at least one membrane adsorber and configured to be connected to a target component collection container; and

[0048] A second outlet valve is connected to the at least one membrane adsorber and is configured to be connected to a waste collection container;

[0049] The switching time between the first outlet valve and the second outlet valve is less than about 3 seconds, preferably less than about 1 second, and most preferably equal to about 0.5 seconds.

[0050] The first and second outlet valves are located after at least one membrane adsorber. In particular, the first and second outlet valves may be located at the end of the flow path.

[0051] The first and second outlet valves are fluidly connected to at least one membrane adsorber, meaning there is a flow path from the at least one membrane adsorber to each of the first and second outlet valves. In other words, fluid can flow from at least one membrane adsorber to the outlet valve. For example, one or more pipes can connect the at least one membrane adsorber to the outlet valve.

[0052] In some instances, one or more other fluid control components may be placed between at least one membrane adsorber and the outlet valve, such as sensors and / or other valves (e.g., membrane valves).

[0053] One of the outlet valves, such as a first outlet valve, is configured, for example, to be connected via a tube to a target component collection container. In other words, the first outlet valve is dedicated to discharging the target component from the flow path into an external container. The second outlet valve is configured, for example, to be connected via a tube to a waste collection container. In other words, the second outlet valve is dedicated to discharging waste (e.g., used buffer solution, DNA, etc.) from the flow path into an external container.

[0054] Therefore, depending on the fluid entering from the flow path, particularly from at least one membrane adsorber at the outlet valve, one outlet valve is open while the other is closed. Each valve can be switched between open and closed positions based on a control signal, for example, from a control system. Exemplarily, the control signal can be based on a sensor that measures the contents of the (partial) fluid flowing to the outlet valve at any given time, such as an absorption detector like an ultraviolet (UV) sensor positioned between the membrane adsorber and the outlet valve. If the fluid contains molecules or particles of a target component exceeding a certain predetermined threshold, the fluid can be referred to as a "target component fluid"; otherwise, the fluid can be referred to as a "waste fluid."

[0055] The valve switching time is the amount of time required for the valve to switch from the open position to the closed position, and vice versa. The switching time of both the first and second outlet valves is less than about 3 seconds, preferably less than about 1 second, and most preferably equal to about 0.5 seconds. In other words, the first and second outlet valves are controlled such that they switch from the open / closed position to the closed / open position in less than about 3 seconds, preferably less than about 1 second, and most preferably equal to about 0.5 seconds.

[0056] Given the high flow rates operating in membrane adsorbers, this relatively short switching time offers two advantages. First, the fact that the first outlet valve can switch from closed to open in such a short time helps eliminate or reduce potential loss of the target component. In fact, if the target component fluid reaches the point in the flow path where the first outlet valve is located, and the first outlet valve is still closed, a portion of the target component fluid may not be properly collected in the target component collection container.

[0057] Secondly, the fact that both outlet valves have short switching times further reduces the potential loss of the target component and also mitigates or eliminates the problem of backmixing. Backmixing refers to the undesirable mixing of fluids caused by fluid movement in a direction different from the forward direction of the flow path.

[0058] Backmixing of the fluid downstream of the membrane adsorber, particularly at the outlet, causes undesirable mixing of the target component fluid with other fluids. This can affect the purity of the collected target component and may, for example, increase the elution volume. The elution volume is the volume of the fraction containing the target component from the start to the end of elution and should therefore be as low as possible to increase concentration and reduce the workload of subsequent steps, such as storage chambers, process time, or buffer consumption.

[0059] Backmixing is more significant in membrane chromatography than in column chromatography. One reason is that the stationary phase volume is much higher in column chromatography; for example, the equivalent column volume for a 150 mL membrane is 10 L, depending on the process design, making the relative change in elution volume negligible in column chromatography. For instance, if the elution volume for a 150 mL membrane adsorber is 200 mL, and the equivalent elution volume for a 10 L column is 15 L, then adding 50 mL of backmixing fluid results in a 25% increase in the membrane chromatography system compared to a 0.3% increase in the column chromatography system.

[0060] Furthermore, due to the smaller stationary phase volume and associated lower binding capacity per cycle compared to conventional column chromatography, membrane chromatography requires a higher number of cycles to process a given volume of feed compared to column chromatography. Given this relatively high number of cycles, the negative impact of backmixing will be significantly increased, rendering the membrane chromatography process ineffective.

[0061] The short switching time of the outlet valve (especially from opening to closing) reduces the amount of fluid that may backflow through the valve. Furthermore, it shortens or eliminates the overlap time when both valves may be open, enabling faster and more precise changes in flow path configuration, which matches the dynamic nature of the membrane adsorber.

[0062] It should be noted that in column chromatography systems, a longer valve switching time (i.e., approximately or greater than 3 seconds) should be selected to protect the packed column bed from rapid pressure fluctuations.

[0063] Another measure to minimize backmixing is to minimize the dead volume of the system, where the dead volume is the volume of the flow path (i.e., the system without a stationary phase), and is therefore given by the sum of the volumes of the conduits, valves, and all other components through which the fluid flows from the inlet to the outlet. Thus, by way of example, the ratio between the dead volume and the stationary phase volume (regardless of the porosity of the stationary phase) can be less than 5, preferably less than 4, even more preferably less than 3, and most preferably less than 2. A smaller dead volume also helps to reduce the duration of the cycle.

[0064] In some instances, the fluid control components of the flow path may further include one or more additional outlet valves positioned after at least one membrane adsorber. Each additional outlet valve may be dedicated to discharging a different component, such as a byproduct, and may be configured to connect to an external container.

[0065] The switching time of the other outlet valve can also be less than about 3 seconds, preferably less than about 1 second, and most preferably equal to about 0.5 seconds.

[0066] In alternative examples, the second outlet valve may have a switching time of approximately 3 seconds or more, but multiple fluid control components may further include a check valve positioned downstream of the second outlet valve. A check valve is a valve that allows fluid to flow in only one direction. Specifically, a check valve allows fluid, such as waste liquid, to flow towards a waste collection container, but not in the opposite direction. The presence of a check valve mitigates or eliminates backmixing problems.

[0067] In this example, the switching time of the first outlet valve can be less than about 3 seconds, preferably less than about 1 second, and most preferably equal to about 0.5 seconds. Optionally, the first outlet valve may have a switching time of about 3 seconds or more. In this case, the plurality of fluid control components may optionally further include another check valve located after the first outlet valve.

[0068] In a particular instance, the plurality of fluid control components may further include:

[0069] The first inlet valve is configured to be connected to the feed fluid supply source;

[0070] The second inlet valve is configured to be connected to the buffer supply source;

[0071] The switching time between the first inlet valve and the second inlet valve is less than about 3 seconds, preferably less than about 1 second, and most preferably equal to about 0.5 seconds.

[0072] The first and second inlet valves are positioned before at least one membrane adsorber. In particular, the first and second outlet valves may be positioned at the beginning of the flow path.

[0073] The first and second outlet valves are fluidly connected to at least one membrane adsorber, meaning there is a flow path from each of the first and second outlet valves to at least one membrane adsorber. In other words, fluid can flow from the inlet valve to at least one membrane adsorber. For example, one or more pipes can connect at least one membrane adsorber to the inlet valve.

[0074] In some instances, one or more other fluid control components may be placed between at least one membrane adsorber and the inlet valve, such as a pump, filter, sensor (e.g., UV sensor) and / or other valve (e.g., membrane valve).

[0075] The first inlet valve is configured, for example, to be connected via a pipe to a feed fluid supply source. In other words, the first inlet valve is dedicated to introducing feed from an external supply source into the flow path. The second inlet valve is configured, for example, to be connected via a pipe to a buffer supply source. In other words, the second inlet valve is dedicated to introducing buffer from an external supply source into the flow path. The second inlet valve may be connected to multiple buffer supply sources, each providing a different buffer. Optionally, the flow path may include multiple (second) inlet valves configured to be connected to multiple buffer supply sources, respectively.

[0076] In one example, the flow path may include two inlet lines, one starting from a first inlet valve and the other from a second inlet valve, where the two inlet lines represent two parallel branches of a flow path that converges before at least one membrane adsorber. In the case of multiple second inlet valves, the flow path may include three or more inlet lines. In another example, the flow path may include a single inlet line, at which the first and second inlet valves are positioned.

[0077] Exemplarily, the flow path may include at least one pump. Each inlet line may have a pump to propel the flow of the corresponding fluid at a defined flow rate. The pump may be specifically integrated into the chromatography system, i.e., it may be a stationary element of the flow path to avoid additional dead volume due to connecting elements.

[0078] Backmixing is problematic not only downstream of the membrane adsorber. Backmixing of the fluid before and / or above the membrane adsorber leads to changes in fluid properties and, due to the small membrane volume, reduces the binding capacity of the target component and / or the elution profile. Similar to what was explained earlier, upstream backmixing also has a smaller negative impact on the column's separation performance / binding capacity compared to the membrane adsorber.

[0079] The short switching time of the inlet valves mitigates or eliminates backmixing issues upstream of the membrane adsorber. In an alternative embodiment, the first and second inlet valves may have switching times of approximately 3 seconds or more, and the multiple fluid control components may further include at least one inlet check valve positioned after the first and second inlet valves. Exemplarily, if the flow path includes at least one pump, the at least one inlet check valve may be positioned after at least one pump.

[0080] In instances with multiple inlet lines, there can be multiple check valves. In instances with only one inlet line, there can be only one inlet check valve.

[0081] More generally, the switching time of all valves in the chromatography system can be less than about 3 seconds, preferably less than about 1 second, most preferably equal to about 0.5 seconds, or, optionally, a check valve can be provided after all valves in the chromatography system.

[0082] In the case of multiple inlet lines, the flow path may further include a mixing valve in each inlet line, such as a first mixing valve and a second mixing valve. The mixing valve can prevent backmixing between different input fluids.

[0083] In one particular example, the plurality of fluid control components may further include a filter configured to filter only the feed fluid. The filter may be specifically used for particle separation and bioburden reduction to avoid stationary phase clogging. The filter may be positioned prior to at least one membrane adsorber in the flow path. The filter may be positioned after an inlet valve configured to allow feed fluid into the flow path.

[0084] For example, the flow path may include an inlet line dedicated to the feed fluid (“feed inlet line”), i.e., solely for feeding. In other words, only the feed fluid flows through the feed inlet line. The filter may be positioned directly (i.e., without a valve) in this feed inlet line such that only the feed fluid flows through the filter.

[0085] In other instances, the filter can be positioned within a portion of the flow path through which different fluids flow. In this case, the filter can be connected to a conduit via two valves (“filter valves”) to create a path through which only the feed can flow, while the flow path provides an alternative route for other fluids.

[0086] The presence of a filter through which the feed fluid flows helps to reduce or eliminate backmixing.

[0087] In a particular example, the at least one membrane adsorber has a first pore size, and the filter has a second pore size smaller than the first pore size. Exemplarily, the first pore size may range from about 3 μm to 5 μm, while the second pore size may range from about 0.2 μm to about 0.8 μm.

[0088] In this way, only bubbles can reach the stationary phase, and these bubbles are sufficiently dispersed to flow through the stationary phase unimpeded, avoiding a decrease in binding capacity. Therefore, the bubble traps typically implemented in column chromatography systems can be eliminated, thus avoiding additional dead volumes.

[0089] In a particular instance, the plurality of fluid control components may further include an absorption detector positioned after the at least one membrane adsorber, wherein the sampling rate of the absorption detector is less than about 0.7 s, preferably less than about 0.5 s, more preferably less than or equal to about 0.3 s.

[0090] As described above, an absorption detector can be used to monitor target components. For example, a UV sensor can record absorption at a defined wavelength (e.g., 280 nm). Elution or collection of the target component is accomplished by opening a dedicated outlet valve (first outlet valve) controlled by this UV signal. The sampling rate of the UV sensor corresponds to the time interval between subsequent recordings at the measurement point and is directly related to the product recovery rate. A sampling rate of less than about 0.7 s, preferably less than about 0.5 s, and more preferably less than or equal to about 0.3 s, ensures that yield loss is reduced or eliminated even for high-flow-rate membrane chromatography.

[0091] In a specific instance, the multiple fluid control components may further include an absorption detector, such as a UV sensor, positioned upstream of at least one membrane adsorber. The presence of an absorption detector upstream of at least one membrane adsorber prevents system failure and / or damage and enables adaptive process control through prediction, as described below.

[0092] If the UV signal varies above / below a predetermined threshold, the process can be stopped (e.g., by stopping the pump), and the cause (e.g., inhomogeneity, microbial contamination, incorrect intermediate links) can be eliminated. Therefore, product loss or changes in the physicochemical properties of the stationary phase will not occur due to, for example, incorrect buffer solution. This may also be related to interrelated processes, such as rejecting feed fluid in the event of quality deviations.

[0093] For example, if the process stops, the fluid present in the system can be discharged via an outlet valve different from the one dedicated to the target component to avoid contamination / dilution of the already collected target component. Alternatively, all outlet valves can be closed when the process stops, for example, when the pump is fully ramped down.

[0094] Similar steps can be taken in the event of air ingress, for example, even if an air sensor is present, or if the air sensor fails. The process can be stopped, and the system can be vented and / or the cause can be eliminated (e.g., buffer reservoir emptying, loose hose connection). Thus, excessive air input into the stationary phase can be avoided.

[0095] The UV detector further enables the system to immediately detect when the flow path upstream of the membrane adsorber is free of UV-active materials. This allows for optimization of rinsing and washing volumes.

[0096] In addition, some process parameters can be directly controlled by upstream UV signals. For example, when the composition of the feed solution changes, the residence time can be reduced or the washing and elution steps adjusted according to the feed concentration. In another instance, in the case of production-related fluctuations in the membrane adsorber (by pre-inputting the binding capacity and / or titer of the target component in the feed), such as in the first cycle or during filling, the loading rate can be adjusted as a function of the UV signal.

[0097] For example, if the concentration of a continuously operating perfusion bioreactor changes, this is recorded by a UV sensor before the stationary phase and can be processed (e.g., through algorithms, multiple linear regression, neural networks, or artificial intelligence), and process parameters can be adjusted according to the changed conditions. This ensures the safety of the chromatographic process and / or identifies potential deviations at an early stage.

[0098] If a UV sensor is present after the membrane adsorber, a comparison of the UV signals before and after the membrane adsorber can provide an assessment of the quality of the separation process. This can be further adapted and automated for process control, for example, based on a variable regeneration step or CIP step that shows a decrease in yield, such as by comparing the peak areas before and after the membrane adsorber.

[0099] In the presence of a filter, a pre-membrane UV sensor further provides filter monitoring capabilities. For example, if the UV signal changes significantly over a given time span, this indicates a change in feed composition or a filter rupture / defect. In this case, downstream fluid is pumped into the waste, the process is interrupted, and the filter can be replaced.

[0100] Furthermore, if the filter is installed in an inlet line dedicated to the feed fluid, the system can perform two-stage chromatography. The first stage is provided by the filter and UV sensor before the membrane adsorber, while the second stage is provided by the membrane adsorber and the UV sensor after it.

[0101] Finally, the pre-film UV sensor can provide control functions for a comparable system.

[0102] Typically, this system configuration with sensor technology preceding the stationary phase enables integrated process control across the entire value chain.

[0103] The features of the chromatographic system described above, particularly the features of the flow path, improve the chromatographic process in terms of efficiency and quality. For example, considering the highly dynamic control of fluid flow and the minimized dead volume in the flow path, the above-described membrane chromatography system is particularly suitable for rapid cyclic chromatography, for example, with a cycle duration of about 3 minutes to about 8 minutes and a residence time of about 10 seconds to about 60 seconds.

[0104] Brief description of the attached figures

[0105] Details of exemplary embodiments are now set forth with reference to the exemplary accompanying drawings. Other features will be apparent from the description, drawings, and claims. However, it should be understood that even though embodiments are described separately, individual features of different embodiments may be combined with other embodiments.

[0106] Figure 1 A conceptual representation of an exemplary chromatography system is shown.

[0107] Figure 2 A conceptual representation of the inlet pipe in the flow path is shown.

[0108] Figure 3 A graph showing the maximum volume of the membrane adsorber is presented, with the maximum volume for which there is no product loss as a function of some characteristics of the flow path.

[0109] Figure 4 An optimization procedure for determining the optimal switching time is shown.

[0110] Figure 5 A plot of UV detection signal versus volume at different sampling rates of the UV filter in a chromatography system is shown.

[0111] Figure 6 A magnified plot of the UV detection signal versus volume at different sampling rates of the UV filter in the chromatographic system is shown.

[0112] Figure 7 The graph shows the UV detection signal versus time for different filter configurations in the chromatography system.

[0113] Figure 8 The diagram shows the conductivity signal versus volume for different filter configurations in the chromatography system.

[0114] Figure 9 A graph showing the normalized area versus normalized volume for different filter configurations in a chromatography system is presented.

[0115] Figure 10 The graphs show UV detection and conductivity signals versus time for different filter configurations in the chromatography system.

[0116] Figure 11 A schematic diagram of an exemplary chromatography system is shown.

[0117] Figure 12 Another schematic diagram of an exemplary chromatography system is shown.

[0118] Detailed Explanation

[0119] In the following detailed description of the examples, reference will be made to the accompanying drawings. It should be understood that various modifications can be made to the embodiments. Unless otherwise expressly stated, elements of one example can be combined and used in other examples to form new examples.

[0120] Figure 1 A conceptual representation of an exemplary chromatography system 100 is shown. The chromatography system 100 includes a flow path 110 and at least one membrane adsorber 200 as a stationary phase. The flow path 110 includes conduits, such as pipes and / or tubing, through which fluid can flow, and it includes a plurality of fluid control components configured to regulate the fluid flow. The chromatography system 100 includes a control system (not shown) configured to manage at least a portion of the fluid control components. The chromatography system 100 may be particularly suitable for membrane chromatography in binding and elution modes.

[0121] Figure 1 and 2 The dashed element in the diagram is optional. Flow path 110 may include one or more inlet lines at the beginning, wherein, in the case of multiple inlet lines, the inlet lines are connected to the main line. (As shown in...) Figure 2 As shown in more detail, an exemplary inlet line includes at least one inlet valve 120 configured to direct an input fluid, such as feed fluid, buffer, or wash fluid, into the flow path. In cases where the flow path 110 includes only one inlet line, the inlet line includes at least two inlet valves 120, one dedicated to the feed fluid and the other to other input fluids. Each inlet valve 120 is configured to connect to at least one input fluid supply source.

[0122] The inlet line also includes a pump 125, and an air sensor 130, configured to detect air in the inlet line, can be installed between the inlet valve 120 and the pump 125. After the pump 125, the inlet line may include a check valve 140, for example, if the switching time of the inlet valve 120 is about 3 seconds or greater. After the check valve 140, other sensors 130, such as pressure sensors and flow meters, can be installed to monitor the inlet line.

[0123] If the inlet line is dedicated to the feed fluid, then after the sensor 130 following the pump 125, the feed inlet line may include a filter 150 configured to filter the feed fluid to, for example, remove some particles. Specifically, the filter may be inserted directly into the feed inlet line, i.e., without a valve. Alternatively, the filter 150 may be located in the main line. See below for reference. Figures 7 to 10 Provides analysis of the impact on filter location.

[0124] If the flow path includes multiple inlet lines, each inlet line may include a mixing valve 145 at its end, i.e., before connecting the main line to the other inlet lines. The mixing valve is provided to separate the different fluids from each other and prevent backmixing, as referenced below. Figure 10 The subject of discussion.

[0125] Back Figure 1 Flow path 110 includes a main pipeline following the inlet line, to which membrane adsorbers 200 are connected. In one example, a single membrane adsorber 200 or a stack of membrane adsorbers 200 on top of each other can be connected to flow path 110. In another example, two membrane adsorbers 200 or two stacks of membrane adsorbers 200 can be connected to flow path 110 in parallel. Using two membrane adsorbers 200 or two parallel stacks allows for a combination of capture and flow patterns or an increase in membrane volume, thereby allowing for an increase in binding capacity. The term "membrane volume" refers to the volume of a single membrane adsorber 200 or a stack of membrane adsorbers 200, taking into account porosity. For example, a membrane volume of 1 L can be the result of a 200 mL membrane layer and a porosity of 800 mL.

[0126] Membrane adsorber 200 can be connected to flow path 110 via a (membrane) valve. The main line can branch into routes without membrane adsorber 200, and the membrane adsorber 200 can be connected to one or two routes.

[0127] If filter 150 is not located in the feed inlet line, the main line of flow path 110 may include filter 150 upstream of membrane adsorber 200. Filter 150 may be connected to the flow path via a (filter) valve. Therefore, the main line may have two alternative branches, one with filter 150 and one without.

[0128] The main pipeline of flow path 110 may include one or more sensors 160 upstream of membrane adsorber 200 (and downstream of filter 150, if present). Specifically, a UV sensor may be positioned upstream of membrane adsorber 200 to provide monitoring and enable adaptive control of the system. Other sensors 160 may include pressure sensors, conductivity sensors, and pH sensors.

[0129] The main pipeline of flow path 110 includes one or more sensors 170 following the membrane adsorber 200. Specifically, at least one UV sensor 170 is positioned between the membrane adsorber 200 and the outlet valve, wherein the UV sensor is configured to detect whether the fluid from the membrane adsorber 200 contains the target component and should therefore be directed to a product collection container or toward another outlet, such as waste. Other sensors 170 may include pressure sensors, conductivity sensors, and pH sensors.

[0130] The control system uses a signal generated by the UV sensor 170 to control an outlet valve located at the end of the flow path downstream of the UV sensor 170. The sampling rate of the UV sensor 170 can be less than about 0.7 s, preferably less than about 0.5 s, and more preferably less than or equal to about 0.3 s. (See below for reference.) Figure 5 and Figure 6 A discussion of sampling rates is given.

[0131] Flow path 110 includes at least two outlet valves 180 and 185, and optionally an additional outlet valve, wherein each outlet valve is configured to be connected to a collection container. Outlet valve 180 may be connected to a target component collection container (and is therefore referred to as “target component outlet valve”), while outlet valve 185 may be connected to a waste collection container (and is therefore referred to as “waste outlet valve”).

[0132] If the switching time of the waste outlet valve 185 is about 3 seconds or more, then the flow path 110 may include a check valve 195 after the waste outlet valve 185. In some instances, if the switching time of the corresponding outlet valve is about 3 seconds or more, then the flow path 110 may include a check valve after each outlet valve.

[0133] For the design of a chromatography system, the flow path between the (post-membrane) UV sensor 170 and the output valve is particularly relevant. The maximum membrane volume V that can operate without loss... MA Combined with volumetric flow rate, and for fast, non-kinetically constrained stationary phases, chromatographic systems can be designed accordingly. This relationship can be derived from the following equations (1) to (4):

[0134]

[0135]

[0136] V = A·L (3)

[0137]

[0138] in The maximum volumetric flow rate without loss is given by d, where d is the diameter, L is the length of the pipe between the UV sensor 170 and the output valve, and t is the maximum volumetric flow rate. tot This is the total signal transmission time. The total signal transmission time consists of all time delays in the signal transmission from the moment the UV sensor detects the passage of the target component until the execution signal, i.e., until the target component outlet valve 180 is opened. Equation (5) shows the time t required by the control system for signal transmission, sensor sampling rate, and valve switching time. tot Exemplary decomposition:

[0139] t tot =t cont +t samp.rate +t switch (5)

[0140] Maximum volumetric flow rate This can be expressed as the membrane volume per unit time.

[0141] Figure 3 The maximum membrane volume without product loss is shown as the tube diameter d, tube length L, and target component outlet valve switching time t for a volumetric flow rate of 5 membrane volumes per minute (MV = 5 / min). switch The function.

[0142] As valve switching time increases and pipe length decreases, the maximum possible volume V... MA Reduced. As the pipe diameter increases, due to the decrease in flow velocity, a higher maximum volume of stationary phase can be obtained with a shorter pipe length.

[0143] Assuming MV = 5 / min and a pipe length of 0.25m, t cont The maximum stationary phase volume V before product loss occurs is 0.25 s. The table below shows the maximum stationary phase volume V before product loss occurs. MA As t tot The function of [the signal transmission time]. As the total signal transmission time increases, the available stationary phase volume and therefore the operating range of the system without product loss decrease.

[0144] 0,25 0 0 855 0,55 0 0.3 388 1,25 0 1 171 1,05 0,5 0,3 204 3,55 3 0,3 60 1,75 0,5 1 122 4,25 3 1 50

[0145] From all the above considerations, it can be seen that, for a given membrane volume, when it comes to minimizing or eliminating product loss, the variable t... tot There are mutual influences among L, d, and MV. Therefore, optimization programs, such as...

[0146]

[0147] It can then be used, for example, to solve for the optimal value through multiple linear regression or other systems of equations. rel.Mr It is the membrane volume and V rel This refers to the flow path or the dead volume of the entire system (e.g., the empty volume including the capsule containing the membrane adsorber). When their ratio is maximized, the results of the chromatographic process are primarily influenced by the characteristics of the chromatographic stationary phase (e.g., the membrane adsorber). The smaller their ratio, the stronger the influence of the flow path.

[0148] Figure 4 The diagram shows the methods for determining the relationship between pipe length / diameter and t. tot The optimal switching time and thus the optimization procedure for determining the applicable stationary phase volume.

[0149] As mentioned above, the sampling rate, in combination with other parameters, plays a role in optimizing the system to avoid product loss. Figure 5 and Figure 6 The effect of individual sampling rates on the performance of the chromatography system is shown.

[0150] Figure 5 A plot of UV detection signal versus volume at different sampling rates of the UV filter in a chromatography system is shown.

[0151] As previously mentioned, the presence of product / target molecules downstream of the membrane adsorber is typically detected by checking if a given condition (“valve switching condition”) is met, i.e., the absorption at a defined wavelength (e.g., 280 nm) is above a given threshold, such as 0.05 AU. As long as the absorption detected, for example by a UV sensor, is above the threshold, the product is collected by keeping the target component outlet valve 180 open.

[0152] Figure 5 It shows the use of The elution peaks of BSA obtained by Q are shown, and the cut points on the elution curves at two different scan rate values ​​(i.e., 1 s and 0.3 s) are also shown. The cut point is the point at which the UV sensor "realizes" that the absorption has exceeded the threshold.

[0153] For different scan rate values, the cut point appears at different times / volumes, and under magnification... Figure 6The difference is clearly illustrated. Although the condition was met at approximately 2525 mL, the UV sensor detected it with a delay in both cases. However, at a flow rate of 45 L / h, detection occurred after less than 4 mL at the faster sampling rate, while at a sampling rate of 1.0 s, detection occurred after more than 12 mL. Higher flow rates result in larger volumetric distances between the cut points.

[0154] The shaded areas represent volumetric intervals during product collection. Product loss can be calculated by considering the differences between the integrals of the entire elution peak and each shaded portion separately.

[0155] 0.3 0.1 1.0 1.1

[0156] Therefore, a decrease in scan rate leads to a decrease in product loss.

[0157] In addition to the sampling rate, reference Figure 3 and Figure 4 Another parameter to consider in conjunction with other parameters is the switching time of the target component outlet valve 180. The following section describes the effect of valve switching time alone on the performance of the chromatographic system, referring to five test examples.

[0158] In tests 1, 2, and 3, elution was performed using water and water / acetone (2-5% v / v) to simulate the product, as acetone, like proteins, absorbs light at a wavelength of 280 nm, making it suitable as a model. In tests 4 and 5, elution was performed using a sample containing 1 L of bovine serum albumin (BSA) (c = 3 g / L) eluted with 0.5 M NaCl. Q was analyzed. For all experiments, the valve switching condition was 0.1 AU. Each test was performed at least 3 times, and appropriate fractions were plotted and analyzed. The results are shown in the table below.

[0159]

[0160] In tests 1 and 2, the switching time between outlet valves 180 and 185 was set to approximately 3 seconds. In test 2, check valve 195 was positioned after waste outlet valve 185. In tests 3, 4, and 5, the switching time between outlet valves 180 and 185 was set to approximately 0.5 seconds.

[0161] Compared to tests 2 and 3, test 1 showed a significantly lower average signal intensity for the collected fractions. Furthermore, the deviation between the extracted fractions was the highest of all tests, at 33.4%. The implementation of check valve 185 resulted in a significantly higher concentration of 0.890 AU and a relative deviation of 3.1%, which was significantly lower than that of test 1. For tests 3, 4, and 5, performance comparable to test 2 was observed.

[0162] Therefore, valve switching time has a significant impact on reproducibility and product concentration, with shorter switching times being better. However, valve switching time should not be too low, i.e., too close to 0 seconds, due to safety considerations, such as pressure development in the system when pumping liquids at high volumetric flow rates. Therefore, a valve switching time of less than about 3 seconds, preferably less than about 1 second, and most preferably equal to about 0.5 seconds can be selected to reduce backmixing and product loss.

[0163] Therefore, the outlet valves 180 and 185 of system 100, and optionally additional outlet valves, are configured to have a switching time of less than about 3 seconds, preferably less than about 1 second, and most preferably equal to about 0.5 seconds. Optionally, outlet valves 180 and 185 may have a switching time of about 3 seconds or longer, and at least waste outlet valve 185 may have a check valve 195 positioned thereafter. If additional outlet valves are present, they may also have check valves positioned thereafter. Optionally, target component outlet valve 180 may also have a corresponding check valve 190.

[0164] Furthermore, the inlet valve 120 can be controlled to have a switching time of less than about 3 seconds, preferably less than about 1 second, and most preferably equal to about 0.5 seconds. Optionally, the inlet valve 120 may have a switching time of about 3 seconds or longer, and each inlet line may include a check valve 140. The same concept applies to all valves in the flow path 110 of system 100.

[0165] Another aspect to consider in the system design is the location of filter 150 (if present). The backmixing varies depending on the location of the pre-filter, which will be discussed below.

[0166] Figure 7 The diagram shows the UV detection signal versus time for different filter configurations in the chromatography system. The three configurations are as follows:

[0167] A) The filter is connected to the main line via a filter valve with a switching time of approximately 3 seconds, allowing only the feed fluid to flow through (dotted line).

[0168] B) The filter is directly inserted into the main pipeline, allowing for the flow of all fluids (solid line).

[0169] C) The filter is directly inserted into the feed fluid inlet line (short dash).

[0170] The same test procedure was performed for each configuration, with the following structure: water equilibration, loading with a 2-5% (v / v) water / acetone mixture, washing with water, manual elution, and regeneration with water. Elution was performed by gradually increasing the water / acetone mixture until a signal of 0.2 AU was reached, at which point regeneration was initiated.

[0171] Configuration A shows a signal drop at approximately 0.8 minutes. Further testing identified an elution peak at 3 minutes and another peak at 3.7 minutes. The concentration drop during loading can be explained by backmixing between the feed solution and water at the filter, due to the piping volume between the pump and filter, and the filter valve switching time. This backmixing results in an undesirable dynamic concentration distribution during loading, negatively impacting the binding properties of the stationary phase.

[0172] In configuration B, the signal did not show a decrease during loading, but it did not reach a constant value. The elution peak was significantly wider than that in configuration A, and a second peak was also visible here. Since all fluids pass through the filter, each fluid mixes with residues from previously filtered fluids. This mixing leads to concentration variations, negatively impacting system performance.

[0173] For configuration C, the signal shows a sharp rise during the loading phase and a spike during the elution phase. A second peak was also identified here. Taken together, this configuration shows the best results for hydrodynamics / backmixing: the signal is stable at all times and exhibits a narrow elution peak.

[0174] While configuration C has the lowest backmix volume, configuration A allows for in-line dilution within the system and also features narrow peaks. For example... Figure 8 As shown, the performance of configuration A can be improved by reducing the switching time of the filter valve.

[0175] Figure 8 The diagram shows a graph of the conductivity signal versus volume for filters with different configurations in the chromatographic system. Specifically, the solid line represents configuration C, where the filter is installed directly in the feed inlet line (also known as an "in-line filter"). The dashed line represents configuration A, where the filter is connected to the main line via two filter valves (also known as "in-line filters"), modified to have a switching time of approximately 0.5 s for the filter valves. Finally, the dotted line also represents a configuration with an in-line filter and a switching time of approximately 0.5 s.

[0176] All curves were obtained by transporting different water and water / acetone mixtures at 45 L / h through their respective filter locations. It can be seen that the performance of the online filter with a valve switching time of 0.5 s is comparable to that of the in-line filter. This is in Figure 9 As can also be seen in the text, Figure 9 A graph showing the conductivity-normalized area versus the signal area centroid-normalized volume for in-line and online filters is presented.

[0177] The less satisfactory performance of configuration B compared to configuration C can be theoretically explained using a balanced dispersion model represented by Equation 7 below, where ci It is the concentration of the components in the feed fluid, u int It is the linear velocity of the feed fluid and D ax It is the axial dispersion coefficient, which is the sum of the contributions from axial molecular diffusion and eddy current diffusion.

[0178] In general rate or equilibrium dispersion models, concentration varies with time, and here it is calculated as the change in concentration with length (i.e., the dimension in the flow direction). Furthermore, the change in concentration with time is divided into convective mass transfer and diffusion / dispersion mass transfer. The convective term describes the concentration flow to the next length segment through changes in linear velocity and length. Diffusion / dispersion mass transfer is described by the axial dispersion coefficient. The axial dispersion size / effect is described by the value of the axial dispersion coefficient and by the change in concentration through a cross-sectional area, which is represented by the second derivative of concentration with respect to length, equivalent to second Fick's law. The second derivative of concentration with respect to length represents backmixing.

[0179] In other words, the concentration change over time is caused by convective transport via linear velocity and backmixing via the axial dispersion coefficient. More precisely, the larger the volume of fluid flow, the greater the effect of backmixing. As shown in Equation 8, the locally considered concentration change θ 2 c i It increases with the sum of the time-concentration changes of the quotients of length and axial dispersion coefficient.

[0180]

[0181]

[0182] C = Concentration of the i-th component [g / L / M]

[0183] t = time [s]

[0184] u = linear velocity [mm / s]

[0185] x = ordinate [mm]

[0186] D ax =Axial dispersion coefficient [mm] 2 / s]

[0187] If the feed flows permanently only through the filter, as in configuration C, backmixing in the system is significantly reduced due to concentration variations within the filter. It is 0.

[0188] If the filter is not installed directly in the inlet line dedicated to the feed, it should only allow the feed to flow through. Furthermore, it should be permanently filled with feed throughout the entire cycle. Therefore, to avoid concentration gradients, the switching time of the filter valve must be regulated by the volume of feed flowing back to the filter valve.

[0189] A second elution peak was detected in all configurations A, B, and C, such as Figure 7 As shown. Figure 10 The conductivity signal (dashed line) for configuration A, excluding the UV signal (solid line), is shown. The conductivity signal is characterized by a small peak at the start of loading, i.e., a salt signal, which reduces the binding capacity of the stationary phase. This undesirable behavior occurs due to the merging of multiple inlet lines without effective backmixing prevention.

[0190] A mixing valve 145 is provided on each inlet line to create a dedicated mixing point and separate different media from each other, so that the concentration gradient is zero up to the mixing point, meaning that backmixing will not occur (see Equation 7). In the case of an inline filter, the presence of the mixing valve also allows for a reduction in the distance between the inlet line junction and the filter location.

[0191] Further measures to reduce backmixing involve the general structure of the flow path from inlet to outlet. Flow paths with minimized bends and turns, or in other words, flow paths that are as straight as possible, reduce the dead volume of the flow path, thereby reducing backmixing.

[0192] Figure 11 and 12 Two examples of chromatographic systems are shown, in which one or more measures for optimizing the chromatographic process, as shown to date, are implemented.

[0193] Figure 11 An exemplary embodiment of a chromatography system 900 is shown. The system 900 has three inlet lines, each including multiple inlet valves 901 / 903 / 905, air sensors 907 / 909 / 911, pumps 913 / 915 / 917, check valves 919 / 921 / 923, pressure sensors 925 / 927 / 929, and flow meters 931 / 933 / 935. One inlet line is used for feed, another for water for in-line dilution, and the last inlet line is used for buffer solution.

[0194] After the three inlet lines are merged, a filter 940 is provided along the flow path. Specifically, the flow path is provided with two filter valves 942 and 944 for connecting the filter 940. The flow path also includes a filter bypass valve 946 and a drain valve 948, which provide an alternative route for the incoming fluid.

[0195] Subsequently, two membrane adsors (or two stacks) 960 and 961 are each connected to the flow path via membrane valves 962 and 963 and 964 and 965, respectively. Each membrane adsorber / stack has a volume of 150 mL. Sensor sets 950 and 970 for measuring pressure, conductivity, pH, and absorption are implemented before and after the membrane adsors 960 and 961. The flow path also includes a membrane bypass valve 966.

[0196] Finally, four outlet valves, 980, 985, 990, and 995, are installed for discharging waste, final products, and various process intermediates.

[0197] In addition to multiple inlet valves 901, 903, and 905, all valves in system 900 are controlled to have a switching time of less than approximately 3 seconds. However, check valves 919, 921, and 923 are implemented after the multiple inlet valves 901, 903, and 905, respectively.

[0198] As mentioned above, due to the smaller stationary phase volume and the associated lower binding capacity per cycle compared to conventional column chromatography, more membrane chromatography cycles are required to process a given volume of feed. However, each cycle is shorter, as can be seen from the table below for protein A chromatography performed using System 900.

[0199]

[0200] The values ​​above refer to membrane chromatography cycles in binding and elution modes, with a fixed transition from one step to the next. The volume of each step is expressed in membrane volume units, which are 150 mL. The residence time of protein-containing solutions on the membrane is ≤20 seconds, as convection is primarily responsible for mass transfer, resulting in more efficient adsorption compared to the diffusion mechanism that dominates in the resin. The dynamic binding time is approximately 20 g / L.

[0201] As mentioned earlier, using Figure 9 The cycle for membrane chromatography performed by the System 900 lasts approximately 7 minutes, while the corresponding cycle using column chromatography takes more than 4 hours.

[0202] Figure 12 Another exemplary embodiment of the chromatography system 1000 is shown. The chromatography system 1000 includes two inlet lines, each inlet line including multiple inlet valves 1001 / 1003, an air sensor 1005 / 1007, a pump 1009 / 1011, a pressure sensor 1013 / 1015, a flow meter 1017 / 1019, and a mixing valve 1021 / 1023. One inlet line is used for feed, while the other inlet line is used for buffer solution.

[0203] After the two inlet lines merge, a filter 1040 is provided along the flow path. Specifically, the flow path is provided with two filter valves 1042 and 1044 for connecting the filter 1040. The flow path further includes a filter bypass valve 1046 and a drain valve 1048, which provide an alternative route for the incoming fluid.

[0204] Subsequently, two membrane adsors (or two stacks) 1060 and 1061 are each connected to the flow path via two membrane valves 1062 and 1063 and 1064 and 1065, respectively. Each membrane adsorber / stack has a volume of 150 mL. Sensor sets 1050 and 1070 for measuring pressure, conductivity, pH, and absorption are implemented before and after the membrane adsors 1060 and 1061. The flow path further includes a membrane bypass valve 1066.

[0205] Finally, four outlet valves, 1080, 1085, 1090 and 1095, are installed for discharging waste, final products and various process intermediates.

[0206] All valves in System 1000 are controlled to have a switching time of less than approximately 3 seconds.

[0207] The duration of each stage of the protein A chromatography cycle performed using System 1000 is reported in the table below:

[0208]

[0209] The values ​​mentioned above refer to the cycle of membrane chromatography in binding and elution modes, with conditional transitions from one step to the next, such as moving to the next step when a given UV absorbance or conductivity value has been reached.

[0210] use Figure 10 The system 1000 performs membrane chromatography with a cycle lasting approximately 4 minutes, therefore the system 1000 is superior to... Figure 9 The system shown is 900 faster. This is partly because, as previously mentioned, the presence of the mixing valve allows for a reduction in the length of the flow path between the inlet line and the filter. Furthermore, the condition switching results in a shorter circulation loop.

[0211] The reduction in backmixing achieved through the structural design and / or flow control measures discussed so far results in a broadening of the low peaks in the elution fraction, leading to a high product concentration in the eluent. Therefore, there is no accumulation of diluent in many cycles, and the chromatographic process is improved in both efficiency and quality.

Claims

1. A chromatographic system configured to process a feed fluid comprising multiple components, wherein at least one of the multiple components of the feed fluid is a target component, and wherein the chromatographic system comprises: The flow path includes multiple fluid control components configured to control fluid flow; A stationary phase, wherein the stationary phase is at least one membrane adsorber connected to the flow path, and the stationary phase is configured to separate the target component; The flow path is configured to optimize the harvesting of the target component; The plurality of fluid control components further include a filter configured to filter only the feed fluid; as well as The at least one membrane adsorber has a first pore size, and the filter has a second pore size, the second pore size being smaller than the first pore size.

2. The chromatography system of claim 1, wherein the plurality of fluid control components comprises: A first outlet valve is connected to the at least one membrane adsorber and configured to be connected to a target component collection container; as well as A second outlet valve is connected to the at least one membrane adsorber and is configured to be connected to a waste collection container; The switching time between the first outlet valve and the second outlet valve is less than 3 seconds.

3. The chromatography system according to claim 2, wherein the switching time between the first outlet valve and the second outlet valve is less than 1 second.

4. The chromatography system according to claim 2, wherein the switching time between the first outlet valve and the second outlet valve is equal to 0.5 seconds.

5. The chromatography system of claim 1, wherein the plurality of fluid control components comprises: A first outlet valve is connected to the at least one membrane adsorber and configured to be connected to a target component collection container; as well as A second outlet valve is connected to the at least one membrane adsorber and is configured to be connected to a waste collection container; A check valve, located downstream of the second outlet valve; The second outlet valve has a switching time of 3 seconds or more.

6. The chromatography system according to any one of the preceding claims, wherein the plurality of fluid control components further comprises: The first inlet valve is configured to be connected to the feed fluid supply source; The second inlet valve is configured to be connected to the buffer supply source; The switching time between the first inlet valve and the second inlet valve is less than 3 seconds.

7. The chromatography system according to claim 6, wherein the switching time between the first inlet valve and the second inlet valve is less than 1 second.

8. The chromatography system according to claim 6, wherein the switching time between the first inlet valve and the second inlet valve is equal to 0.5 seconds.

9. The chromatography system according to any one of claims 1 to 5, wherein the plurality of fluid control components further comprises: The first inlet valve is configured to be connected to the feed fluid supply source; The second inlet valve is configured to be connected to the buffer supply source; At least one inlet check valve located after the first inlet valve and the second inlet valve; as well as The first inlet valve and the second inlet valve have a switching time of 3 seconds or more.

10. The chromatography system according to any one of claims 1 to 5, wherein the plurality of fluid control components further comprises an absorption detector positioned after the at least one membrane adsorber, wherein the sampling rate of the absorption detector is less than 0.7 s.

11. The chromatographic system of claim 10, wherein the sampling rate of the absorption detector is less than 0.5 s.

12. The chromatographic system of claim 10, wherein the sampling rate of the absorption detector is less than or equal to 0.3 s.

13. The chromatography system of claim 6, wherein the plurality of fluid control components further comprises an absorption detector positioned after the at least one membrane adsorber, wherein the sampling rate of the absorption detector is less than 0.7 s.

14. The chromatographic system of claim 13, wherein the sampling rate of the absorption detector is less than 0.5 s.

15. The chromatographic system of claim 13, wherein the sampling rate of the absorption detector is less than or equal to 0.3 s.

16. The chromatography system of claim 7, wherein the plurality of fluid control components further comprises an absorption detector positioned after the at least one membrane adsorber, wherein the sampling rate of the absorption detector is less than 0.7 s.

17. The chromatographic system of claim 16, wherein the sampling rate of the absorption detector is less than 0.5 s.

18. The chromatographic system of claim 16, wherein the sampling rate of the absorption detector is less than or equal to 0.3 s.

19. The chromatography system of claim 8, wherein the plurality of fluid control components further comprises an absorption detector positioned after the at least one membrane adsorber, wherein the sampling rate of the absorption detector is less than 0.7 s.

20. The chromatographic system of claim 19, wherein the sampling rate of the absorption detector is less than 0.5 s.

21. The chromatographic system of claim 19, wherein the sampling rate of the absorption detector is less than or equal to 0.3 s.

22. The chromatography system of claim 9, wherein the plurality of fluid control components further comprises an absorption detector positioned after the at least one membrane adsorber, wherein the sampling rate of the absorption detector is less than 0.7 s.

23. The chromatographic system of claim 22, wherein the sampling rate of the absorption detector is less than 0.5 s.

24. The chromatographic system of claim 22, wherein the sampling rate of the absorption detector is less than or equal to 0.3 s.

25. The chromatography system according to any one of claims 1 to 5, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

26. The chromatography system of claim 6, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

27. The chromatography system of claim 7, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

28. The chromatography system of claim 8, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

29. The chromatography system of claim 9, wherein the plurality of fluid control components further comprises an absorption detector positioned upstream of the at least one membrane adsorber.

30. The chromatography system of claim 10, wherein the plurality of fluid control components further comprises an absorption detector positioned upstream of the at least one membrane adsorber.

31. The chromatography system of claim 11, wherein the plurality of fluid control components further comprises an absorption detector positioned upstream of the at least one membrane adsorber.

32. The chromatography system of claim 12, wherein the plurality of fluid control components further comprises an absorption detector positioned upstream of the at least one membrane adsorber.

33. The chromatography system of claim 13, wherein the plurality of fluid control components further comprises an absorption detector positioned upstream of the at least one membrane adsorber.

34. The chromatography system of claim 14, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

35. The chromatography system of claim 15, wherein the plurality of fluid control components further comprises an absorption detector positioned upstream of the at least one membrane adsorber.

36. The chromatography system of claim 16, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

37. The chromatography system of claim 17, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

38. The chromatography system of claim 18, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

39. The chromatography system of claim 19, wherein the plurality of fluid control components further comprises an absorption detector positioned upstream of the at least one membrane adsorber.

40. The chromatography system of claim 20, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

41. The chromatography system of claim 21, wherein the plurality of fluid control components further comprises an absorption detector positioned upstream of the at least one membrane adsorber.

42. The chromatography system of claim 22, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

43. The chromatography system of claim 23, wherein the plurality of fluid control components further comprises an absorption detector positioned upstream of the at least one membrane adsorber.

44. The chromatography system of claim 24, wherein the plurality of fluid control components further comprises an absorption detector positioned prior to the at least one membrane adsorber.

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