Polysorbate Quantification and Degradation Analysis via LC and Charged Aerosol Detection

Researchers from ThermoFisher Scientific in Shanghai, China reviewed polysorbate quantification and degradation analysis using liquid chromatography coupled with charged aerosol detection. Their findings were published in the Journal of Chromatography A (1).

Aerosol dispenser | Image Credit: © Alexey Achepovsky - stock.adobe.com

In this review, the researchers discussed the qualitative and quantitative analysis of polysorbates (PS), profiling its composition, investigating reasons for degradation, and discussing reaction mechanisms. PS are the most frequently used nonionic surfactants in biopharmaceutical formulations, acting as emulsifiers and solubilizers for poorly soluble drug substances to prevent unwanted immune responses. By combining high-performance liquid chromatography (HPLC) and charged aerosol detectors (CADs), given their spreading applications for qualitatively and quantitatively analyzing PS, the scientists summarized the latest advancements for facilitating the study and application of PS.

Commercial PS products are complex heterogeneous mixtures, with significant variations existing in PS chemical compositions, not only between different suppliers but also between different lots from a single supplier. PS degradation products and impurities can cause toxic effects and protein instability. Understanding the mechanisms behind particle formation is vital, as these particles can potentially trigger immunogenic responses and compromise the stability of the protein therapeutics, the authors wrote (1).

One of the techniques used to handle PS is HPLC. HPLC is a widely used technique in analytical chemistry, with spectrophotometric detectors being the predominantly employed type of detector used in this process. However, reaction uncertainties and complications with different types of detectors can complicate its application in PS. Evaporative aerosol detectors have gained significant attention over the past few decades, with CADs being a notable type of alternative detector. CADs measure the overall charge deposited on aerosolized particles to produce signals proportional to the mass of analyte present, which applies to compounds with or without a chromophore (2). One benefit of CAD systems is its ability to quantitate a wide range of non-volatile compounds in absence of standards due to uniform response factor for the analytes in question. The Corona CAD system, developed by ThermoFisher Scientific, was first introduced to the scientific community at the Pittsburgh Conference, now Pittcon, in 2005. The system received both the Pittsburgh Conference Silver Pittcon Editor’s Award and the R&D 100 award in recognition of its potential (3).

Combining LC with CAD holds great potential for advancing PS analysis, providing sensitive response signals for a wide range of compounds. This technique can help analyze PS-containing formulations in pharmaceuticals, personal care products, and food additives. Further, it can offer valuable insights into the stability, impurity profiles, and degradation of PS-based formulations, aiding in quality control and regulatory compliance. CAD can also enable detection for low-level impurities or contaminants in PS-based products, deepening research on degradation mechanisms and informing preservation and application strategies. If researchers continue making advancements in instrumentation, method development, and application diversification, CAD will be vital in the analysis and quality control of PS-containing formulations across various industries.

References

(1) Shi, L.; Shen, G.; Chai, R.; Gamache, P. H.; Jin, Y. A Review of Polysorbate Quantification and Its Degradation Analysis by Liquid Chromatography Coupled with Charged Aerosol Detection. J. Chromatogr. A 2025, 1742, 465651. DOI: 10.1016/j.chroma.2024.465651

(2) Barnhart, W. W.; Farooq, M. Q.; Ahmad, I. A. H. A Simplified Tutorial on Charged Aerosol Detection: Understanding the Basics, Optimization, and Troubleshooting. J. Chromatogr. Open 2024, 6, 100181. DOI: 10.1016/j.jcoa.2024.100181

(3) CAD History. ThermoFisher Scientific 2025. https://www.thermofisher.com/us/en/home/industrial/chromatography/chromatography-learning-center/liquid-chromatography-information/hplc-system-components/how-hplc-detectors-work/charged-aerosol-detection.html?erpType=Global_E1 (accessed 2025-4-9)