{"id":4739,"date":"2022-08-24T14:55:15","date_gmt":"2022-08-24T14:55:15","guid":{"rendered":"https:\/\/www.thermofisher.com\/blog\/analyteguru\/review-of-analytical-methods-for-quantifying-amp-profiling\/"},"modified":"2026-08-25T23:30:21","modified_gmt":"2026-08-25T23:30:21","slug":"review-of-analytical-methods-for-quantifying-amp-profiling","status":"publish","type":"post","link":"https:\/\/www.thermofisher.com\/blog\/analyteguru\/review-of-analytical-methods-for-quantifying-amp-profiling\/","title":{"rendered":"Review of Analytical Methods for Quantifying, Profiling Polysorbates with Charged Aerosol Detection"},"content":{"rendered":"
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Polysorbates (PS) are amphiphilic non-ionic surfactants used as emulsifiers, stabilizers and solubilizers in pharmaceutical and biopharmaceutical formulations, foods and even cosmetics.<\/p>\n

\"\"<\/span>Accurate measurement of PS is essential for the quality and safety of products. The problem is, most commercially available PS materials are complex heterogenous mixtures of hundreds of molecules, including low-level components such as impurities and degradants.<\/p>\n

Two analytical approaches for measuring PS by HPLC analysis are typically used: a single peak method for quantitation, and a profiling method capable of measuring and quantifying many components to determine quality.<\/p>\n

Published methods around these two approaches differ, with one variation tied to the type of detector. Common methods use mass spectrometry, charged aerosol detection (CAD), or evaporative light scattering detection (ELSD).<\/p>\n

This blog explores the chemistry behind why PS compounds are complex, compares the single peak and profiling methods, and highlights why CAD is superior to ELSD for PS analysis.<\/p>\n

<\/span>The chemistry behind why polysorbate compositions are complex and variable<\/strong><\/p>\n

\"\"Characterizing the purity, stability and degradation products of PS compounds in a complex mixture often presents analytical challenges for a few reasons: (I) the starting materials are impure mixtures<\/a>, (II) PS is prone to degradation, and (III) PS in the final product<\/a> is present at only around 20% of the expected structure.<\/p>\n

Variations in chemical profiles can occur from lot-to-lot due to inconsistency of the synthetic process<\/a> and may influence the behavior of PS in liquid formulations.<\/p>\n

These differences can affect the solubility of free fatty acids impurities, leading to the formation of unwanted particulates<\/a> in the final product.<\/p>\n

Regulatory requirements defined by the European Pharmacopeia<\/a> and US Pharmacopeia 790<\/a> are strict regarding the presence of particles in injectable drugs, as they are generally supposed to be \u201cessentially\/practically free of visible particles.\u201d<\/p>\n

And particle formation in injectables is one of the leading causes of recalls<\/a>.<\/p>\n

Let\u2019s take a deeper dive into the synthetic route<\/strong><\/h3>\n

Polysorbates are produced by the esterification of polyoxyethylene sorbitan with a fatty acid.<\/p>\n

The different types of PS compounds \u2013 like polysorbate 20 (PS20) and polysorbate 80 (PS80) \u2013 are defined by the chain length of the parent acid.<\/p>\n