Figure 8: Batch-to-batch control of the peak retention time by the gradient elution of a two component separation by cation exchange chromatography, feed forward of desired set point, multivariable feedback controller with decoupling. A pH disturbance in the elution buffer is introduced in cycle 3, causing the controller to adjust the gradient to restore the retention times.
Conclusions
This paper presents a methodology, based on a lab-scale platform, for fast development of digital solutions in integrated continuous downstream processes. The fundamental building block is the Orbit supervisory controller that can control and communicate physical setups and their associated local control software. Orbit is an open, flexible and extendable software, which opens up the operation of the setup to any computational tool. Many different kind of processing steps and configurations has been implemented and operated using the methodology. These setups can be connected and configured into complex processing systems and a network of Orbit controllers makes it possible to operate almost autonomous. Both the configuration and automation of multiple processing steps and support systems are vital for sustainable and autonomous operation for long-term studies of digital solutions.
During processing of the integrated continuous downstream process platform data are streamed to the Orbit database. The on-line generated data is heterogeneous, asynchronous and distributed. The data are design and configuration information, real-time detector signals, asynchronous chemical analysis data, real-time data analysis information and on-line computational results. The Orbit software contains methods for automatic generation of mechanistic models and model calibration. This makes it possible to perform advanced data analysis, data-driven or mechanistic modelling, optimization and machine learning. The results can directly be implemented into the Orbit automation and control system for on-line processing. The conclusion is that the physical and digital platform are well suited for development, study and validation of real-time digital twin application in downstream processing.

CRediT authorship contribution statement

Niklas Andersson : Conceptualization, Methodology, Software, Writing (review & editing), Supervision, Visualization, Project administration.
Joaquín Gomis-Fons : Conceptualization, Methodology, Software, Validation, Visualization.
Madèlene Isaksson: Conceptualization, Methodology, Software, Validation, Visualization.
Simon Tallvod : Conceptualization, Methodology, Software, Validation, Visualization.
Daniel Espinoza : Conceptualization, Methodology, Software, Validation, Visualization
Linnea Sjökvist : Methodology, Software, Validation, Visualization
Gusten Zandler Andersson : Methodology, Software, Validation, Visualization
Bernt Nilsson : Conceptualization, Methodology, Resources, Writing (review & editing), Supervision, Visualization, Project administration, Funding acquisition.
Acknowledgement
This project has received funding Vinnova, (through the Competence Centre for Advanced BioProduction by Continuous Processing, AdBIOPRO) under Grant 2016‐05181, Grant 2019‐05314 (AutoPilot project), Grant 2022-01477 (AutoADD project) and finally from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No 812909.
References
Andersson, N., Löfgren, A, Olofsson, M, Sellberg, A., and Nilsson, B. (2017): ”Design and Control of Integrated Chromatography Columns Sequences”, Biotechnol. Prog. , 33:923-930
Andersson, N., Gomis-Fons, J., Nilsson, B. (2022): ”Smart platform for development of small-scale integrated continuous downstream processes”,AChE, doi:10.1016/bs.ache.2022.03.004
Baur D, Angarita M, Müller‐Späth T, Steinebach F, Morbidelli M. Comparison of batch and continuous multi‐column protein A capture processes by optimal design. Biotechnology Journal . 2016a;11(7):920-931.
Baur D, Angarita M, Muller-Spath T, Morbidelli M. Optimal model-based design of the twin-column CaptureSMB process improves capacity utilization and productivity in protein A affinity capture.Biotechnol J . Jan 2016b;11(1):135-45.
Baur D, Angelo JM, Chollangi S, Xu, X., Müller‐Späth T, Zhang, N., Ghose, S., Li, Z., Morbidelli M. Model assisted comparison of Protein A resins and multi-column chromatography for capture processes.Journal of Biotechnology . 2018/11/10/ 2018;285:64-73.
Borg N, Brodsky Y, Moscariello J, Vunnum, S., Vedantham, G., Westerberg, K., Nilsson, B. Modeling and robust pooling design of a preparative cation-exchange chromatography step for purification of monoclonal antibody monomer from aggregates. Journal of Chromatography A . 2014/09/12/ 2014;1359:170-181.
Espinoza, D., Andersson, N., Nilsson, B. (2022A): ”In-silico formulation of iterative learning control for chromatographic purification od biopharmaceuticals”, In Proceedings of ESCAPE32 2022, Toulouse, France
Espinoza, D., Andersson, N., Nilsson, B. (2022B): ”Binary separation control in preparative gradient chromatography using iterative learning control”, J Chrom A 1673, 463078
Farid SS. Process economics of industrial monoclonal antibody manufacture. J Chrom B . Mar. 2007;848(1):8-18.
Feidl F, Vogg S, Wolf M, Podobnik, M., Ruggeri, C., Ulmer, N., Wälchli, R., Souquet, J., Broly, H., Butté, A., Morbidelli, M. Process-wide control and automation of an integrated continuous manufacturing platform for antibodies. Biotechnology and Bioengineering . 2020;117(5):1367-1380.
Godawat R, Brower K, Jain S, Konstantinov K, Riske F, Warikoo V. Periodic counter-current chromatography – design and operational considerations for integrated and continuous purification of proteins.Biotechnol J . Dec 2012;7(12):1496-508.
Godawat R, Konstantinov K, Rohani M, Warikoo V. End-to-end integrated fully continuous production of recombinant monoclonal antibodies.J Biotechnol . Nov. 2015;213(Supplement C):13-19.
Gomis-Fons, J., Andersson, N. and Nilsson, B., (2020A) “Optimization study on periodic counter-current chromatography integrated in a monoclonal antibody downstream process”. J Chrom A ., 1621 (2020) 461055
Gomis-Fons, J., Schwarz, H., Zhang, L., Andersson, N., Nilsson, B., Castan, A., Solbrand, A., Stevenson, J., Chotteau, V. (2020B) “Model-based design and control of a small-scale integrated continuous end-to-end mAb platform”. Biotechnol. Prog ., DOI: 10.1002/btpr.2995
Gomis-Fons, J., Yamanee-Nolin, M., Andersson, N. and Nilsson, B., (2021) “Optimal loading flow rate trajectory in monoclonal antibody capture chromatography”. J Chrom A., 1635 (2020) 461760
Isaksson, M., Gomis Fons, J., Andersson, N., Nilsson, B., (2023): “An automated buffer management system for small-scale continuous downstream bioprocessing”, J Chrom A , revision
Kesik-Brodacka M. Progress in biopharmaceutical development.Biotechnol Appl Biochem . 2018;65(3):306-322. doi:10.1002/bab.1617
Konstantinov KB, Cooney CL. White Paper on Continuous Bioprocessing May 20–21 2014 Continuous Manufacturing Symposium. J Pharm Sci . Mar. 2015;104(3):813-820.
Löfgren, A., Gomis-Fons, J., Andersson, N. Nilsson, B., Berghard, L., and Lagerqvist Hägglund, C. (2021) “An integrated continuous downstream process with real-time control: A case study with periodic counter-current chromatography and continuous virus inactivation”.Biotechnol Bioeng ., doi: 10.1002/bit.27681
Moreno-González, M., Keulen, D., Gomis-Fons, J., Gomez, G. L., Nilsson, B., and Ottens, M., (2021) “Continuous adsorption in food industry: The recovery of sinapic acid from rapeseed meal extract”. J SepPur.,254 (2021) 117403
Ng CKS, Osuna-Sanchez H, Valéry E, Sørensen E, Bracewell DG. Design of high productivity antibody capture by protein A chromatography using an integrated experimental and modeling approach. Journal of Chromatography B . 2012/06/15/ 2012;899(Supplement C):116-126.
Nilsson, B., and Andersson, N. (2017): Simulation of Process Chromatography, In Preparative Chromatography for Separation of Proteins , First Ed., Editors Staby, Rathore and Ahjua, Wiley, Chap 3, pp 81-110.
Rathore AS, Nikita S, Thakur G, Deore N. Challenges in process control for continuous processing for production of monoclonal antibody products. Current Opinion in Chemical Engineering . 2021/03/01/ 2021;31:100671.
Saleh D, Wang G, Müller B, Rischawy, F., Kluters, S., Studts, J., Hubbuch, J.. Straightforward method for calibration of mechanistic cation exchange chromatography models for industrial applications.Biotechnology Progress . 2020;36(4):e2984.
Scheffel,J., Isaksson, M., Gomis-Fons, J., Schwarz, H., Andersson, N., Norén, B., Solbrand, A., Hober, S., Nilsson, B., Chottaeu, V., (2022): ”Design of an integrated continuous downstream process for acid-sensitive monoclonal antibodies based on a calcium-dependent Protein A ligand”. J Chrom A 1664
Schwarz, H., Gomis-Fons, J., Isaksson, M., Scheffel, J., Andersson, N., Andersson, A., Castan, A., Solbrand, A., Chottaeu, V., Hober, S., Nilsson, B. (2022): ”Integrated continuous biomanufacturing at pilot-scale for acid-sensitive monoclonal antibodies”. Biotechnol Bioeng , DOI: 10.1002/bit.28120
Sellberg, A., Holmqvist, A, Magnusson, F, Andersson, C, and B. Nilsson (2017): ”Discretized multi-level trajectory: A proof-of-concept demonstration”, J. of Chrom A, 1481, 73-81
Shukla AA, Thömmes J. Recent advances in large-scale production of monoclonal antibodies and related proteins. Trends in Biotechnology . 2010/05/01/ 2010;28(5):253-261.
Steinebach F, Ulmer N, Wolf M, Decker, L., Schneider, V., Wälchi, R., Karst, D., Souquet, J., Morbidelli, M. Design and operation of a continuous integrated monoclonal antibody production process.Biotechnology Progress . 2017;33(5):1303-1313.
Tallvod, S., Espinoza, D., Gomis-Fons, J., Andersson, N., Nilsson, B. (2023): “Automated quality analysis in continuous downstream processes for small-scale applications” , report, Dept of Chemical Engineering, Lund University
Tallvod, S., Andersson, N., Nilsson, B. (2022A): ”Automation of Modeling and Calibration of Integrated Preparative Protein Chromatography Systems”, Processes 10, 945
Tallvod, S., Yamanee-Nolin, M., Gomis-Fons, J., Andersson, N., Nilsson, B. (2022B): ”A novel process design for automated quality analysis in an integrated biopharmaceutical platform”, In Proceedings of ESCAPE32 2022, Toulouse, France
Tiwari, A., Masampally, V.S., Agarwal, A., Ratore, A. (2022) Digital twin of continuous chromatography process for mAb purification: Design and model-based control. Biotechnology and Bioengineering . 2022; DOI: 10.1002/bit.28307.
Vogg S, Müller-Späth T, Morbidelli M. Current status and future challenges in continuous biochromatography. Current Opinion in Chemical Engineering . 2018/12/01/ 2018;22:138-144.
Walther J, Godawat R, Hwang C, Abe Y, Sinclair A, Konstantinov K. The business impact of an integrated continuous biomanufacturing platform for recombinant protein production. J Biotechnol . Nov. 2015;213:3-12.
Zydney AL. Perspectives on integrated continuous bioprocessing—opportunities and challenges. Current Opinion in Chemical Engineering . 2015/11/01/ 2015;10(Supplement C):8-13.