Endotoxin Characterization – Effects of Metal Ions on Endotoxins Zeta Potential under Various Concentrations and pH Conditions

Elvina Clarie Dullah; Clarence M. Ongkudon

Abstract and References

Transactions on Science and Technology Vol. 4, No. 3-3, 432 - 436, 2017

Endotoxin Characterization – Effects of Metal Ions on Endotoxins Zeta Potential under Various Concentrations and pH Conditions

Elvina Clarie Dullah, Clarence M. Ongkudon

ABSTRACT
Endotoxin has unique characteristics such as ability to form a stable interaction with other biomolecules as well as high temperature and pH tolerance. These characteristics make its removal difficult especially during the production of biotherapeutic drugs. Endotoxins contamination in biopharmaceutical products can result in sepsis, tissue damage, inflammation, fever and even lead to death. The choice of an efficient method in removing endotoxins from biopharmaceutical products is rather perplexing as the method could affect the biological properties of the products. Previous studies have found that divalent metal ions, such as zinc sulphate, calcium chloride and magnesium chloride have better aggregative effects on endotoxins compared to that on plasmid DNA, thus, these metal ions may be potentially useful in the selective removal of endotoxin from biopharmaceutical products. The main focus of this study was to investigate the effects of metal ions effects on endotoxins under various parameters such as pH and concentration. In the present study, zeta potential analysis was employed to measure the effects of metal ions on endotoxin. The observed experimental data showed significant changes in zeta potential of endotoxins when compared with the control (i.e., untreated endotoxin). Apparently, the magnitude of zeta potential of endotoxins changed after treatments with metal ions at different pH and concentrations. Therefore, it can be concluded that the apparent effect of metal ions on endotoxins zeta potential increases in the order of Zn²⁺<Ca²⁺< Mg²⁺. This study serves as a basis for improved endotoxin monitoring in biomanufacturing.

KEYWORDS: Endotoxin; Lipopolysaccharide; Zeta potential; Divalent metal cations; Endotoxin characterization

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