Multi-Attribute Analysis of Monoclonal Antibodies Using the Agilent InfinityLab 2D-LC Solution and Q-TOF MS

Significance of Multi-Attribute Analysis of Monoclonal Antibodies

Monoclonal antibodies (mAbs) require monitoring of multiple critical attributes during development and production. Combining affinity chromatography, size exclusion, and mass spectrometry in a single workflow addresses the complexity of mAb heterogeneity and accelerates characterization.

Objectives and Study Overview

This study demonstrates an automated three-dimensional on-line platform that integrates protein A affinity capture for titer determination, SEC for size variant separation, and reversed-phase desalting for high-resolution mass analysis directly from cell culture supernatants.

Methodology and Instrumentation

The system uses an Agilent 1290 Infinity II 2D-LC with multiple heart-cutting valves and an Agilent 6530 Q-TOF LC/MS. The workflow comprises:

• First dimension: Protein A affinity chromatography (pH 7.4 binding, acidic elution)
• Second dimension: Size exclusion chromatography (150 mM phosphate buffer, pH 7)
• Third dimension: RPLC desalting cartridge for salt removal
• Detection by diode array detectors at 220 and 280 nm and high-resolution MS
• Control and data processing via Agilent OpenLab CDS and MassHunter BioConfirm

Main Results and Discussion

Key outcomes include:

• Accurate mAb quantitation with linear response over 10–100 µg load
• Efficient heart-cutting reveals high- and low-molecular weight variants with ≥95.6% peak purity
• Automated capture of multiple SEC fractions in 40 µL loops for individual MS analysis
• Deconvoluted MS spectra confirm the intact mAb sequence and glycoform distribution (G0F, G1F, G2F)
• Detection of mAb dimers (∼300 kDa, 1.0%) and clipped species (3.2%)
• Excellent precision in retention times (RSD <0.2%) and peak areas (RSD <3%) over replicate runs
• Biosimilar clone screening compares originator and CHO clones, identifying a point mutation in one clone by a 68 Da mass shift

Benefits and Practical Applications

The multi-attribute analyzer offers:

• Comprehensive profiling of mAb titer, aggregation, sequence, and post-translational modifications in one run
• Streamlined workflow reducing sample handling and instrument changes
• Enhanced throughput for clone selection, process optimization, and quality control
• Applicability across research, development, and manufacturing labs

Future Trends and Application Possibilities

Potential advancements include:

• Integration of additional chromatographic modes for charge variant analysis
• AI-assisted method development and data interpretation
• High-throughput implementations for large-landscape screening
• Extension to other biotherapeutics such as fusion proteins and antibody-drug conjugates

Conclusion

The developed 3D on-line LC platform enables fully automated, detailed multi-attribute analysis of mAbs directly from culture supernatants with high precision and throughput, supporting accelerated biopharma development.

Reference

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4. Sandra K. et al. Heart-Cutting and Comprehensive Two-Dimensional Liquid Chromatography in Monoclonal Antibody Clone Selection. J. Chromatogr. A 2017, 1523, 283–292
5. Stoll D. et al. Characterization of Therapeutic Antibodies and Related Products by Two-Dimensional Liquid Chromatography Coupled with UV Absorbance and Mass Spectrometric Detection. J. Chromatogr. B 2016, 1032, 51–60