Automated platform buffer screening for multiple proteins on Big Kahuna

Significance of Platform Buffer Screening

Buffer composition has a profound influence on the conformational, chemical and colloidal stability of therapeutic proteins. Identifying an optimal formulation early in biologics development minimizes degradation, aggregation and formulation liability. Automated high-throughput buffer screening accelerates this process, reduces manual variability and supports rapid decision-making in research and quality control settings.

Objectives and Study Overview

This application note demonstrates how the Big Kahuna automated platform performs a comprehensive buffer screen for four monoclonal antibodies (mAbs) across a matrix of 12 unique formulations. Key aims:

• Assess throughput and consistency of automated ultrafiltration/diafiltration (UF/DF).
• Quantify buffer exchange efficiency, protein recovery and final concentration.
• Validate a workflow combining Big Kahuna with acoustic sensing and automated concentration measurement.

Methodology and Instrumentation

Four mAbs (A–D) were prepared at ~10 mg/mL and exchanged into a base buffer of 10 mM histidine at pH 6.0 or 6.2, each containing one of five excipients (150 mM NaCl, 150 mM sucrose, 75 mM mannitol, 150 mM arginine, 100 mM glycine) or no additive. Each condition was run in duplicate (48 total samples) on a single Unfilter 96 plate. The automated protocol targeted 96 % total buffer exchange per pool with 67 % volume removal per cycle. Big Kahuna dynamically adjusted pressurization times per cycle based on real-time volume feedback from an onboard acoustic sensor.

Instrumentation:

• Big Kahuna automated UF/DF platform with Unfilter 96 filter plate.
• Acoustic volume sensor for precise on-deck volume measurement.
• Lunatic spectrophotometer using the A280 application for protein concentration.
• LEA software suite (Library Studio Design Creator and Automation Studio) for assay design and execution.

Main Results and Discussion

The buffer exchange sequence required seven cycles, each averaging 9.3 minutes, for a total runtime of ~307 minutes to process 96 samples. Initial fill volumes measured 430 ± 11 µL and final volumes 426 ± 15 µL, indicating consistent liquid handling. The average percent exchange across all pools was 98.4 % (range 96.7–>99.9 %). Final protein concentrations matched initial values (10 ± 0.5 mg/mL) and mass recoveries exceeded 97 % for all samples, demonstrating minimal product loss and high reproducibility.

Advantages and Practical Applications

Automating buffer screening with Big Kahuna offers:

• High throughput: 96 distinct samples per run.
• Reduced hands-on time and operator error.
• Real-time process control via acoustic sensing.
• Consistent protein recovery and concentration accuracy.

Future Trends and Potential Applications

Future enhancements may include on-deck buffer preparation and pH titration to further minimize manual input. Integrating direct data transfer between Lunatic and Big Kahuna could enable closed-loop workflows where concentration results automatically trigger downstream steps. Such advances will support seamless formulation screening in process development and quality laboratories.

Conclusion

The Big Kahuna platform effectively automates multi-protein buffer screening, delivering rapid, reproducible exchange of four mAbs into 12 formulation conditions within five hours. Dynamic pressurization control ensures high exchange efficiency and protein recovery. This workflow significantly streamlines early-stage formulation development for biologics.

References

• Unchained Labs. Automated platform buffer screening for multiple proteins on Big Kahuna. Application Note, Rev C, 2019.