Traditionally the most sensitive method for detection of endotoxins has been the LAL (Limulus Amebocyte Lysate) test but over the last few years the issue of Low Endotoxin Recovery (LER) has been raised, a recently published paper concludes the LER phenonmenon is caused by endotoxin masking and not by test interference.
Read the full paper here: Reich J, et al., Masking of endotoxin in surfactant samples: Effects on Limulus-based detection systems, Biologicals (2016), http://dx.doi.org/10.1016/j.biologicals.2016.04.012
