Automated viscometry measurement with Junior

Importance of the Topic

Monoclonal antibodies are critical therapeutics whose high-concentration formulations often exhibit increased viscosity, complicating manufacturing and administration. Rapid, accurate viscosity measurement is essential during formulation screening to predict developability and optimize drug delivery.

Objectives and Study Overview

This study compares automated microcapillary viscometry using the Unchained Labs Junior viscosity station with a conventional Malvern Kinexus rotational rheometer across six antibody concentrations (20–200 mg/mL). The goal was to evaluate speed, sample consumption, automation level, and result consistency.

Used Instrumentation

• Unchained Labs Junior platform with integrated viscosity station
• Malvern Kinexus rotational rheometer

Methodology

• Calibration of the Junior station with deionized water and Brix standards for 1–51 cP range
• Automated washing, drying, and sample loading using disposable positive-displacement pipette tips (100 µL sample volume)
• Viscosity calculated from pressure response over multiple shear rates at 20 °C, total cycle per sample ~6 minutes
• Kinexus measurements followed manufacturer’s protocol with 180 µL sample and manual cleaning, taking ~30 minutes per run

Main Results and Discussion

• Both systems yielded comparable viscosity trends across all concentrations.
• At high shear, viscosity increased from ~1 cP at 20 mg/mL to >200 cP at 200 mg/mL, with low shear showing similar profiles.
• Differences in absolute values reflect mechanistic and operational variances between capillary and rotational methods.
• Junior station enabled unattended operation and consistent replicate precision (RSD <10%).

Benefits and Practical Applications

• Junior viscosity station processes over 200 samples per day with minimal hands-on time (25 minutes), versus ~40 samples in 20 hours on the Kinexus rheometer.
• Sample volume reduced by >40% and operator intervention eliminated during measurement runs.
• Integration with other assays (pH, turbidity, particle analysis) on the Junior or Big Kahuna platform accelerates formulation workflows.

Future Trends and Potential Applications

Automated viscometry is poised to become integral in high-throughput formulation screening and quality control. Coupling viscosity data with predictive developability models and integrating multi-parameter analytical platforms will further streamline drug candidate selection and process development.

Conclusion

The Unchained Labs Junior viscosity station delivers viscosity data comparable to a benchtop rheometer with fivefold higher throughput and 40-fold reduced hands-on time. Its automation and low sample requirement make it a powerful tool for biologics formulation and screening.

References

1. Lorenz T, et al. Developability Assessment of Biologics by Integrated Biologics Profiling. American Pharmaceutical Review. 2014.
2. Yang X, et al. Developability studies before initiation of process development. mAbs. 2013;5(5):787–794.