Bioanalytical
Microplate reader
Measures absorbance, fluorescence or luminescence in the wells of 96- or 384-well plates. It is the read-out instrument for ELISA, protein assays, cell-based assays and enzyme kinetics.
- Biotechnology
- Biopharmaceutical
- Clinical research
- Academic research
- Food (allergen ELISA)
- Environmental (toxicity assays)
TROUBLESHOOTING
Common problems, causes and fixes
Readings unstable or drift
Likely causes
- • Lamp not warmed up or ageing
- • Condensation on plate (cold plate in warm reader)
What to do
- • Allow warm-up; replace lamp if energy low
- • Equilibrate plates to room temperature before reading
Random outlier wells
Likely causes
- • Bubbles or particles
- • Scratched or dirty plate bottom
- • Pipetting error
What to do
- • Remove bubbles and centrifuge
- • Use new plates and handle by the edges
- • Check pipettes and technique
Outer wells read higher or lower
Likely causes
- • Evaporation during incubation
- • Temperature gradient across the plate
What to do
- • Use plate seals and humidified incubation
- • Pre-warm reagents and plates; avoid stacking plates
Calibration plate values out of tolerance
Likely causes
- • Dirty or damaged filters
- • Lamp or detector fault
- • Expired calibration plate certificate
What to do
- • Clean filters as the supplier advises
- • Service the reader
- • Recertify or replace the calibration plate
Standard curve flattens at high concentration
Likely causes
- • Above the photometric linear range
- • Substrate exhausted in the assay
What to do
- • Dilute samples into range
- • Shorten development time or adjust the assay
High background in fluorescence
Likely causes
- • Wrong plate colour (clear plate)
- • Autofluorescence of medium or plate
- • Gain set too high
What to do
- • Use black plates
- • Use phenol-red-free medium or blank-correct
- • Optimise gain on the highest standard
In LimsPulse · Calibration Management
Keep every Plate reader in control: usage logs, calibration and maintenance schedules, and automatic blocking of overdue instruments.