Figure 1: Schematic process of LPS masking.
In aqueous solution, LPS naturally forms aggregates such as micelles or vesicles. Addition of chelators (such as citrate) weakens the aggregate structure by removing divalent cations. Detergents like polysorbate (e.g. Tween-20) then intercalate into the aggregates. Eventually, the aggregates completely disperse into monomers. Factor C, which triggers the LAL-coagulation-cascade, cannot be activated by LPS-monomers, leading to false negatives when quantifying masked LPS5.
