• Sensitive method for endotoxin determination in nanomedicinal product samples.

      Giannakou, Christina; Aimonen, Kukka; Bloois, Louis van; Catalán, Julia; Geertsma, Robert E; Gremmer, Eric R; de Jong, Wim H; Keizers, Peter Hj; Schwillens, Paul Lwj; Vandebriel, Rob J; et al. (2019-01-01)
      Aim: Nanomaterials and nanomedicinal products tend to interfere with various commonly used assays, including regulatory required endotoxin detection methods for medicines. We developed a method to quantify endotoxin levels that is compatible with nanomaterials and nanomedicinal products. Materials & methods: The method is based on measuring endotoxin indirectly via 3-hydroxylated fatty acids of lipid-A, using Ultra High Performance Liquid Chromatography coupled with mass spectrometry. The outcome was related to results of the commonly used Limulus Amebocyte Lysate method. Results: The ultra high performance liquid chromatography coupled with mass spectrometry method has clear advantages compared with other endotoxin determination assays; particularly the absence of nanospecific interference. Conclusion: The method is sensitive, straightforward and accurate in determining and quantifying endotoxin in nanomedicinal product samples.