Speed up and simplify formulation screens with Big Tuna and Stunner

Significance of the topic

Buffer exchange is critical to formulation and developability screening of biologics but manual approaches are time-consuming and inconsistent. Integrating automated low-volume high-throughput systems addresses bottlenecks by reducing hands-on time sample consumption and variability while improving reproducibility.

Objectives and overview

This application note demonstrates how coupling Unchained Labs Big Tuna automated buffer exchanger with the Stunner integrated UV/Vis and dynamic light scattering DLS system streamlines formulation screening. Four monoclonal antibodies were assessed in a 96-well format with various buffer excipient combinations to evaluate recovery aggregation and colloidal stability parameters in a single high-throughput workflow.

Methodology and instrumentation

Big Tuna employs pressure-based ultrafiltration diafiltration with customizable membrane MWCO options 10 kDa in Unfilter 96 and 24 plates to process 96 samples 100–450 µL or 24 samples 0.45–8 mL respectively. Stunner integrates UV/Vis absorbance for concentration and DLS SLS measurements for size polydispersity and second virial coefficient B22 on 2 µL samples.

• Big Tuna automated UF/DF system
• Unfilter 96-well plates with regenerated cellulose 10 kDa MWCO
• Stunner plate-based UV/Vis and DLS instrument
• Monoclonal antibodies mAb1 mAb2 adalimumab trastuzumab
• Excipients histidine buffer pH 6 PS80 NaCl sucrose arginine

Main results and discussion

Big Tuna achieved >90% recovery in 15 of 16 antibody excipient combinations with consistent target concentration and minimal sample loss. DLS measurements on Stunner confirmed monodisperse profiles hydrodynamic diameter 10–12 nm PDI ≤0.1 for most formulations except adalimumab in sucrose showing aggregation.
Colloidal stability screening via B22 and diffusion interaction parameter kD across concentration series revealed that sucrose alone provided the most repulsion for mAb1 and trastuzumab while combined sucrose arginine favored mAb2. Adalimumab displayed negative B22 and kD in all tested buffers indicating higher aggregation propensity. Early identification of these stability trends can inform formulation decisions before scale-up.

Benefits and practical use

• Automated buffer exchange reduces hands-on time and variability in high-throughput screens
• Low sample volume requirements preserve valuable biologics during screening
• Integrated concentration and size analysis accelerates go no-go decisions on formulation candidates
• Early detection of aggregation propensity through B22 and kD measurements guides formulation optimization

Future trends and applications

Automated miniaturized workflows combining UF DF and multi-parametric analysis will become standard in early biologics development.
Integration with robotic liquid handlers and advanced data analytics may further enhance throughput and decision-making.
Expansion to additional biotherapeutic modalities eg fusion proteins bispecifics and complex matrices will broaden applicability.

Conclusion

The synergy between Big Tuna and Stunner enables rapid reproducible buffer exchange and comprehensive formulation screening in a single workflow. This approach accelerates candidate selection by combining high recovery rates with detailed colloidal stability insights ultimately reducing risks and timelines in biologics development.

Reference

1. Kaszuba M et al Measuring sub-nanometre sizes using dynamic light scattering J Nanopart Res 2008 10(5) 823–829
2. Connolly BD et al Weak interactions govern the viscosity of concentrated antibody solutions high-throughput analysis using the diffusion interaction parameter Biophys J 2012 103(1) 69–78
3. Wilson W et al Colloidal behavior of proteins effects of the second virial coefficient on solubility crystallization and aggregation of proteins in aqueous solution Curr Pharm Biotechnol 2006 6(6) 427–436