RT-MALS − Real-time product attributes, from lab to plant

Importance of the Topic

Real-time monitoring of product attributes during bioprocessing is critical for implementing Quality by Design (QbD) and advancing Bioprocess 4.0. Traditional PAT approaches rely on indirect process parameters, leading to delays and limited visibility into product quality. Multi-angle light scattering (MALS) integrated in-line or on-line offers direct, rapid measurement of key attributes such as molar mass, size and particle concentration, enabling real-time release and more efficient process control.

Goals and Overview of the White Paper

This white paper presents the development and application of real-time MALS (RT-MALS) as a PAT tool for biopharmaceuticals and nanomedicines. It outlines how RT-MALS shifts focus from process parameters to direct product measurements, reviews available workflows from lab-scale to pilot and production environments, and highlights the benefits for process development, scale-up and manufacturing.

Methodology

RT-MALS combines multi-angle static light scattering (MALS), dynamic light scattering (DLS) and UV absorption to determine absolute molar mass, hydrodynamic size and particle concentration in real time. Measurements can be performed at rates up to five data points per second, with minimal sample preparation. OBSERVER software orchestrates automated sampling, data acquisition and trigger-driven pooling decisions.

Used Instrumentation

• ultraDAWN RT-MALS instrument (Wyatt Technology)
• DynaPro DLS detector
• OBSERVER real-time analysis software (versions 1.0–1.5)
• On-line/inline UV absorbance detector
• FPLC or process skid with digital I/O synchronization
• OPC-UA communication interface

Main Results and Discussion

RT-MALS workflows have been demonstrated for:

• Continuous-flow protein purification using hydrophobic interaction chromatography, detecting aggregate breakthrough at <0.25% dimer level
• On-line polysaccharide depolymerization end-point determination
• In-line monitoring of liposome size during formulation
• Inline AAV enrichment by anion-exchange chromatography, measuring capsid concentration, full/empty ratio and aggregate content in real time

Compared with off-line SEC-MALS runs that require tens of minutes per fraction and lab turnaround time, RT-MALS delivers attribute measurements in seconds, greatly accelerating process optimization.

Benefits and Practical Applications

Implementing RT-MALS enables:

• Direct product monitoring and automated pooling based on real-time attribute thresholds
• Reduced reliance on indirect surrogates and extensive process modelling
• Higher yields through smaller safety margins
• Shorter development timelines and faster time-to-market
• Improved consistency and potential for continuous manufacturing

Future Trends and Opportunities

As demand grows for scalable PAT, future developments will focus on:

• Extending RT-MALS to higher flow rates and full GMP production scales
• Deepening integration via OPC-UA and enterprise control systems
• Incorporating advanced data analytics and AI for predictive control
• Broadening applications to additional modalities such as vaccines and novel gene therapies

Conclusion

RT-MALS represents a paradigm shift from process parameter monitoring to direct, real-time product attribute measurement. By enabling rapid feedback and automated control, this technology supports QbD, accelerates development and enhances manufacturing consistency for biopharmaceuticals and nanomedicines.

Reference

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