Surfactants are vital substances in the formulation of biopharmaceuticals, as they enhance the stability of therapeutic proteins. The most commonly used surfactants in biopharmaceutical products are polysorbate 20 (PS20) and polysorbate 80 (PS80). Degradation products of these surfactats can lead to the destabilization of protein therapeutics, increased immunogenicity, and consequently reduced drug safety. Therefore, industrial companies are committed to developing alternative surfactants. Within the framework of this master’s thesis, we compared the stability of established surfactants with a new compound, VEDG-3,3, a surfactant excipient designed based on accumulated knowledge of the advantages and limitations of polysorbates. We aimed to evaluate how VEDG-3,3 behaves under different stress conditions and whether it offers advantages over existing surfactants. To this end, aqueous surfactant solutions were prepared in the experimental part and subjected to stress conditions such as elevated temperature and light exposure, which provided accelerated conditions to obtain a broader picture of how different gaseous headspaces (oxygen, nitrogen), pH variations, and the presence of enzymes (lipases, esterases, proteases) affect the stability of the tested compounds. Surfactant content after stress exposure was determined using high-performance liquid chromatography (HPLC) coupled with a charged aerosol detector (CAD). Initially, we examined the stability of aqueous surfactant solutions and found that their stability under thermal stress (up to 40 °C) was generally good, indicating that degradation within this short time frame in this range is not critical. Strong light stress induced degradation of all surfactants, with PLX188 being the most sensitive, whereas PS80 and VEDG showed comparable stability. Analysis of the influence of the gaseous headspace revealed that molecular oxygen strongly accelerates surfactant oxidation under light, while a nitrogen headspace has a protective effect. Using a design of experiments (DOE) approach, all factors were combined, revealing that pH and buffer type were the most influential factors on surfactant degradation. The effect of buffers was pronounced: the histidine buffer negatively affected mainly PS80, whereas VEDG did not show such effects, indicating its compatibility with one of the most commonly used buffers in biopharmaceuticals. Enzymatic studies confirmed higher enzymatic stability of VEDG compared to PS80, especially in the presence of lipase and protease. VEDG showed some sensitivity to esterase, which would be worth further investigation.
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