Protein quality control in SPR and BLI high-throughput screening studies

Importance of the Topic

Surface plasmon resonance (SPR) and bio-layer interferometry (BLI) are cornerstone techniques for high-throughput screening of biotherapeutic candidates. Reliable binding data from these assays require pristine protein samples free of aggregates or foreign particles. Implementing a rapid, non-perturbative quality control step using high-throughput dynamic light scattering (HT-DLS) helps prevent data artifacts, microfluidic blockages and wasted resources during SPR and BLI campaigns.

Objectives and Study Overview

This study evaluates the integration of HT-DLS, performed in industry-standard microplates, as a preliminary quality assessment for protein solutions prior to SPR and BLI screening. The goal is to establish a seamless workflow that identifies problematic samples, ensures confidence in kinetic and affinity measurements, and preserves instrument integrity during large-scale candidate evaluation.

Methodology and Instrumentation

The approach relies on dynamic light scattering to measure Brownian motion of particles and compute their hydrodynamic radii via autocorrelation analysis. By scanning 96-, 384- or 1536-well plates in situ, HT-DLS generates size distributions and assigns quality bins (high, intermediate, low) through an automated heat map. A built-in camera documents each well to distinguish true particulates from loading errors.

Instrumentation

• DynaPro Plate Reader for HT-DLS measurements
• Standard microplate formats (96, 384, 1536 wells)
• Surface plasmon resonance and bio-layer interferometry systems drawing samples directly from plates

Main Results and Discussion

HT-DLS screening of protein solutions accomplished full-plate QC in under 45 minutes. Wells classified as high quality displayed narrow monomeric peaks, intermediate wells showed minor oligomer or nanoparticle presence, and low-quality wells contained visible aggregates or precipitates. Pre-screening prevented flow-cell clogging, eliminated spurious sensorgram spikes from particulate contaminants, and provided diffusion coefficients for assessing mass-transfer limitations in SPR.

Benefits and Practical Applications

• Reduces failed binding assays by excluding aggregated or contaminated samples
• Preserves microfluidic channels and flow cells, minimizing downtime and maintenance
• Maintains data integrity by avoiding signal noise, skewed kinetics and inaccurate concentration estimates
• Streamlines drug discovery workflows through an integrated plate-based QC step

Future Trends and Potential Applications

Advancements may include coupling HT-DLS data with machine learning models to predict aggregation propensity, extending quality control to buffer systems and excipient screening, and integrating optical QC modules into next-generation screening platforms. Expansion of plate-reader formats and faster analysis algorithms will further accelerate biopharmaceutical candidate evaluation.

Conclusion

Introducing high-throughput dynamic light scattering as an upstream quality check transforms SPR and BLI screening into more robust, reliable processes. Early detection of aggregates and particulates safeguards instruments, enhances data accuracy and accelerates therapeutic candidate selection.

References

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3. Razinkov I., Treuheit V.J. & Becker G.W. Methods of High Throughput Biophysical Characterization in Biopharmaceutical Development. Curr. Drug Discov. Technol. 10, 59–70 (2013).