Choice of method for endotoxin detection depends on nanoformulation

Area of Science:

• Nanotechnology
• Biotechnology
• Analytical Chemistry

Background:

• Nanoparticles can interfere with standard endotoxin detection methods.
• Accurate endotoxin quantification is critical for clinical-grade nanoformulations.

Purpose of the Study:

• Compare limulus amoebocyte lysate (LAL) assay performance across different formats with clinical nanoformulations.
• Evaluate the utility of the macrophage activation test (MAT) for resolving LAL assay discrepancies.

Main Methods:

• Tested clinical-grade nanoformulations using turbidimetric, gel-clot, and chromogenic LAL assays.
• Utilized MAT to verify results for formulations showing discrepancies among LAL tests.

Main Results:

• No single LAL format proved optimal for all tested nanoformulations.
• The gel-clot LAL method was unreliable for resolving discrepancies with certain nanoformulations.
• MAT effectively verified LAL findings for nanoformulations without cytotoxic drugs.

Conclusions:

• Diverse LAL assay formats yield variable endotoxin quantification for nanoformulations.
• The gel-clot LAL assay is not universally suitable for discrepancy resolution.
• MAT serves as a valuable complementary assay for endotoxin verification in non-cytotoxic nanoformulations.