•Adsorption isotherm accuracy and precision is dependent on experimental variables.•Studying isotherms both at equilibrium and through elution can improve data reliability.•Multicomponent isotherms ...quantified using UV spectra and multivariate data analysis.•Analytical bottleneck alleviated with rapid high throughput analytics.
The combination of multi-well plates and automated liquid handling is well suited to the rapid measurement of the adsorption isotherms of proteins. Here, single and binary adsorption isotherms are reported for BSA, ovalbumin and conalbumin on a strong anion exchanger over a range of pH and salt levels. The impact of the main experimental factors at play on the accuracy and precision of the adsorbed protein concentrations is quantified theoretically and experimentally. In addition to the standard measurement of liquid concentrations before and after adsorption, the amounts eluted from the wells are measured directly. This additional measurement corroborates the calculation based on liquid concentration data, and improves precision especially under conditions of weak or moderate interaction strength. The traditional measurement of multicomponent isotherms is limited by the speed of HPLC analysis; this analytical bottleneck is alleviated by careful multivariate analysis of UV spectra.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Chromatography is a widely used method in the biotechnology industry and functions to separate the desired product from process and product related impurities. There is a multitude of resins ...available based on different modalities (such as charge, hydrophobicity, and affinity) to provide a spectrum of approaches to meet the separation challenges of the diverse products. The challenge of developing viral antigen purification processes is addressed in this method. A unique feature of this product class is that in order to protect against more than one strain of an antigen, vaccines are often multivalent. This entails multiple production processes for each antigen, all of which will require separate development and validation. Ideally, a universal purification method is sought, but differences in the protein subunits (frequently used as the antigens) make this challenging and often-bespoke purification steps are required. This means process development for the chromatographic stages of these products can be particularly challenging and labour intensive. With the numerous choices available, making critical process decisions that are usually unique to each product, process, and strain, can be costly and time-consuming. To address this, scale down purification at <1.0 mL column volume and automation approaches are increasingly applied to increase throughput. In this work, a method is described wherein a Tecan Freedom EVO
automated liquid handler is deployed for the evaluation of different resin chemistries and buffer conditions to find a suitable purification strategy. This method allows for the rapid evaluation of the separation viral antigens where limited information on chromatography behavior is known at the early stages of process development. Here, we demonstrate the methodology firstly by explaining the automated purification script and secondly by applying the script for an efficient purification development for different serotypes of rotavirus antigens.
•Poros 50 HS, in bind and elute mode, separates empty and full CVA21 particles.•The separation is optimal at low elution pH conditions.•The separation can also be achieved when performed in ...flowthrough mode.•Multiple cation exchange resins can separate empty and full CVA21 particles.•Poros 50 HS, in bind and elute mode, separates full CVA21 particles from impurities.
Members of the enterovirus genus are promising oncolytic agents. Their morphogenesis involves the generation of both genome-packed infectious capsids and empty capsids. The latter are typically considered as an impurity in need of removal from the final product. The separation of empty and full capsids can take place with centrifugation methods, which are of low throughput and poorly scalable, or scalable chromatographic processes, which typically require peak cutting and a significant trade-off between purity and yield. Here we demonstrate the application of packed bed cation exchange (CEX) column chromatography for the separation of empty capsids from infectious virions for a prototype strain of Coxsackievirus A21. This separation was developed using high throughput chromatography techniques and scaled up as a bind and elute polishing step. The separation was robust over a wide range of operating conditions and returned highly resolved empty and full capsids. The CEX step could be operated in bind and elute or flowthrough mode with similar selectivity and returned yields greater than 70% for full mature virus particles. Similar performance was also achieved using a selection of other bead based CEX chromatography media, demonstrating general applicability of this type of chromatography for Coxsackievirus A21 purification. These results highlight the wide applicability and excellent performance of CEX chromatography for the purification of enteroviruses, such as Coxsackievirus A21.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Live virus vaccine (LVV) purification, employing chromatography, can be challenged by low binding capacities and elution yields. Alternatively, processes relying solely on enzymatic digestion steps ...and size‐based membrane separations can be limited by suboptimal reduction of process related impurities and poorly scalable unit operations. Here, we demonstrate that the combination of flowthrough mode chromatography and an ultrafiltration/diafiltration (UF/DF) unit operation delivers a purification process for two different LVV candidates, V590 and Measles, expressed in adherent Vero cells. For V590, chromatography with mixed mode cation exchange resins returned final product yields of ∼50% and logarithmic reduction values (LRVs) of 1.7–>3.4 and 2.5–3.0 for host cell DNA (hcDNA) and host cell proteins (HCPs), respectively. For Measles, chromatography with mixed mode anion exchange resins returned final product yields of ∼50% and LRVs of 1.6 and 2.2 for hcDNA and HCPs, respectively. For both V590 and Measles processing, the employed resins cleared a key HCP, fibronectin, which could foul the UF/DF unit operation, and thusly enabling it to further reduce HCPs and to formulate the final LVV products. This integrated purification process utilizes the complementary action of the two unit operations and its applicability across LVVs supports its consideration for their processing.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Bioprocess development studies often involve the investigation of numerical and categorical inputs via the adoption of Design of Experiments (DoE) techniques. An attractive alternative is the ...deployment of a grid compatible Simplex variant which has been shown to yield optima rapidly and consistently. In this work, the method is combined with dummy variables and it is deployed in three case studies wherein spaces are comprised of both categorical and numerical inputs, a situation intractable by traditional Simplex methods. The first study employs in silico data and lays out the dummy variable methodology. The latter two employ experimental data from chromatography based studies performed with the filter‐plate and miniature column High Throughput (HT) techniques. The solute of interest in the former case study was a monoclonal antibody whereas the latter dealt with the separation of a binary system of model proteins. The implemented approach prevented the stranding of the Simplex method at local optima, due to the arbitrary handling of the categorical inputs, and allowed for the concurrent optimization of numerical and categorical, multilevel and/or dichotomous, inputs. The deployment of the Simplex method, combined with dummy variables, was therefore entirely successful in identifying and characterizing global optima in all three case studies. The Simplex‐based method was further shown to be of equivalent efficiency to a DoE‐based approach, represented here by D‐Optimal designs. Such an approach failed, however, to both capture trends and identify optima, and led to poor operating conditions. It is suggested that the Simplex‐variant is suited to development activities involving numerical and categorical inputs in early bioprocess development.
In this study, a grid compatible Simplex method is deployed in downstream investigations involving HT chromatographic techniques with the aim to identify optimal operating conditions. Here, the explored input spaces involve both numerical and categorical variables. The method, together with the definition of dummy variables, allows for a rapid identification of optima while dealing, seamlessly, with the complexities accrued by the simultaneous consideration of numerical and ordinal categorical inputs. This work demonstrates that the approach is suited to typical early stage development activities and at the same time it expands the applicability domain of Simplex based methods in general
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
During the development of a SARS‐CoV‐2 vaccine candidate, at the height of the COVID‐19 pandemic, raw materials shortages, including chromatography resins, necessitated the determination of a ...cleaning in place (CIP) strategy for a multimodal core‐shell resin both rapidly and efficiently. Here, the deployment of high throughput (HT) techniques to screen CIP conditions for cleaning Capto Core 700 resin exposed to clarified cell culture harvest (CCCH) of a SARS‐CoV‐2 vaccine candidate produced in Vero adherent cell culture are described. The best performing conditions, comprised of 30% n‐propanol and ≥0.75 N NaOH, were deployed in cycling experiments, completed with miniature chromatography columns, to demonstrate their effectiveness. The success of the CIP strategy was ultimately verified at the laboratory scale. Here, its impact was assessed across the entire purification process which also included an ultrafiltration/diafiltration step. It is shown that the implementation of the CIP strategy enabled the re‐use of the Capto Core 700 resin for up to 10 cycles without any negative impact on the purified product. Hence, the strategic combination of HT and laboratory‐scale experiments can lead rapidly to robust CIP procedures, even for a challenging to clean resin, and thus help to overcome supply shortages.
Graphical and Lay Summary
A chimeric SARS‐CoV‐2 live virus vaccine candidate (VSVΔG‐SARS‐CoV‐2) was purified via Capto Core 700 chromatography. High Throughput (HT) scale column chromatography was deployed to screen cleaning in place (CIP) agents and to test a CIP strategy for 10 cycles. This involved the determination of product purities and yields and of the presence of foulants post CIP in resin extracts from miniature (600 μL) columns between cycles. The results were verified at 20 mL column scale for 10 batches. This work demonstrates that HT scale techniques can lead to effective CIP strategies for chromatography resins.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The High Throughput (HT) investigation of chromatographic separations is an important element of downstream bioprocess development due to the importance of chromatography as a technique for achieving ...stringent regulatory requirements on product purity. Various HT formats for chromatography exist, but the miniature column approach has characteristics resembling large scale packed bed column chromatography the most. The operation of such columns on robotic stations can be automated, but this is not always a straightforward procedure; the robotic manipulations are highly dependent on the settings of each experiment and the standard commands of the supporting software may not provide readily the required flexibility and accessibility for “plug and play” functionality. These can limit the potential of this technique in laboratories engaging on HT activities. In this work, we present an application which aims to overcome this challenge by providing end‐users with a flexible operation of the miniature column technique on an automated liquid handler. The application includes a script which is written on Freedom EVOware, and is supplemented by custom compiled executables. Here, the manipulations carried out by the application are described in detail and its functionality is demonstrated through typical experiments based on bind and elute miniature column chromatography. The application is shown to allow for the unsupervised “on‐the‐fly” programming of the robotic station and to ultimately make the technique accessible to non‐automation experts. This application is therefore well suited to simplifying development activities based on the robotic deployment of the miniature column chromatography technique.
Miniature columns are suitable for downstream bioprocessing activities. However, their deployment requires expertise in robotic programming. Here, an application is described aiming to reduce this technique to a routinely deployed tool. It employs an advanced script, and custom executables, converting user inputs to robotic instructions and operations, and ultimately, processed results, in a fully unsupervised fashion. These make the technique accessible to non‐automation experts, enhance its high throughput nature, and serve to unlock its potential for bioprocess development.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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