Endotoxin Testing for Research Peptides Explained
What the LAL assay measures and why the result belongs on every COA.
By PX1 Research Team · August 4, 2026
Endotoxin Testing for Research Peptides Explained
The assay
Limulus amebocyte lysate (LAL) testing detects bacterial endotoxin, reported in endotoxin units per milligram (EU/mg).
Why it matters
Endotoxin is a common confounder in cell-culture and in-vivo research models — it can produce inflammatory readouts that have nothing to do with the compound under study.
Where to find ours
PX1 publishes endotoxin results per lot at /endotoxin-reports.
How PX1 documents every lot
Every PX1 lot ships with HPLC purity, LC-MS identity, residual solvent, moisture (Karl Fischer), sterility and endotoxin data. Lot documentation is published at /purity-reports, /endotoxin-reports and /coa. Synthesis, purification, lyophilization and vial fill happen in U.S. facilities — see /manufacturing-process.
Research use only. PX1 Research supplies compounds for laboratory and in-vitro research. Nothing here is medical advice, a dosing recommendation, or an offer for human or veterinary use. Figures cited are reported from published laboratory literature.