Microbiology & sterility
Endotoxin (LAL) reader
An incubating photometer that holds LAL reactions at 37 °C and measures the change in absorbance or turbidity over time. Software turns the reaction onset time into an endotoxin concentration in EU/mL using a standard curve.
- Pharmaceutical
- Biotech
- Medical devices
- Dialysis and hospital pharmacy
- Research laboratories
TROUBLESHOOTING
Common problems, causes and fixes
Standard curve |r| below 0.980
Likely causes
- • Poor CSE dilution or vortexing
- • Pipetting errors
- • Temperature not uniform
What to do
- • Prepare fresh standards with full vortexing
- • Check pipette calibration and technique
- • Check reader temperature calibration
Negative control shows endotoxin
Likely causes
- • Contaminated LRW, tips or tubes
- • Environmental contamination during set-up
What to do
- • Use a new lot of LRW and consumables
- • Clean the work area and repeat
PPC recovery below 50%
Likely causes
- • Product inhibition (pH, chelators, protein binding)
- • Spike added incorrectly
What to do
- • Dilute further (not beyond the MVD)
- • Adjust pH or use a dispersing buffer
- • Repeat with correct spiking
PPC recovery above 200%
Likely causes
- • Product enhancement
- • Glucan interference
- • Endotoxin contamination of the spiked sample
What to do
- • Dilute further
- • Use a glucan-blocking buffer or glucan-insensitive reagent
- • Repeat with fresh consumables
Very short onset in all wells
Likely causes
- • Contaminated LAL reagent
- • Reader temperature too high
What to do
- • Use a new reagent vial
- • Check temperature
In LimsPulse · Calibration Management
Keep every Endotoxin reader in control: usage logs, calibration and maintenance schedules, and automatic blocking of overdue instruments.