LAL test and RPT for endotoxin detection of CPT-11/DSPE-mPEG2000 nanoformulation: What if traditional methods are not applicable?

Endotoxin can be measured mainly by two methods: the Rabbit Pyrogen Test (RPT) and Limulus Amebocyte Lysate (LAL) assay. We found that a chemotherapeutic drug nanoformulation composed of irinotecan hydrochloride and an amphiphilic molecule DSPE-mPEG2000 can interfere with the LAL. Furthermore, the RPT results indicated that at a relatively high dosage, the drug irinotecan hydrochloride can induce a hypothermia effect which forces us to reduce the dose. So it is necessary to develop new methods for the detection of endotoxin.