β-Glucan Interference: Why rFC Testing May Be Superior
One of the most significant limitations of traditional LAL-based endotoxin testing is its susceptibility to interference from β-glucans. Understanding this interference pathway and its solution is important for interpreting endotoxin test results correctly.
What Are β-Glucans?
β-Glucans are polysaccharides found in the cell walls of fungi, yeasts, and some plants. They are structurally distinct from bacterial endotoxins but can activate a parallel pathway in the LAL cascade.
The Interference Problem
In the horseshoe crab coagulation cascade, there are two activation pathways:
- Factor C pathway: Activated specifically by bacterial endotoxins (LPS)
- Factor G pathway: Activated by β-glucans
Traditional LAL assays detect the endpoint of both pathways, meaning they cannot distinguish between endotoxin contamination and β-glucan contamination. This can lead to false-positive results that may cause unnecessary batch rejections.
The rFC Solution
Recombinant Factor C (rFC) assays use only the endotoxin-specific Factor C enzyme, completely bypassing the Factor G pathway. This makes rFC assays inherently immune to β-glucan interference.
Benefits of rFC for Peptide Testing:
- No false positives from β-glucan contamination
- True endotoxin-specific results
- More consistent lot-to-lot performance
- Animal-free (no horseshoe crab harvesting required)
When β-Glucan Interference Matters
β-Glucan interference is particularly relevant when:
- Products are manufactured in facilities that also process fungal-derived materials
- Cellulose-based filters are used in the production process
- Wooden or paper-based packaging materials contact the product
- Environmental fungal contamination is present
Evolve Aminos Testing Approach
We select endotoxin testing methods that minimize interference risks, ensuring that our quality data accurately reflects the true contamination status of our products.