8. Troubleshooting
LB 925 Crocodile miniWorkstation
Page 58 of 68
84024BA2 Rev. 03, 04/2020
High background
Cross-Reactivity
Detection antibody is cross-reacting with coating
antibody. Run appropriate controls.
Poor quality water was
used to wash the plates
or to prepare the wash
solution
Check the water quality. If it is questionable, try an
alternative water source, such as bottled distilled
water.
Substrate solution has
deteriorated
Make sure that the substrate is colorless prior to
addition to the plate.
Priming is recommended to be done directly before
the dispense step.
Non-specific binding of
antibodies
Use appropriate blocking buffer.
Concentration of
conjugated second
antibody too high
Perform dilutions to determine optimal working
concentration.
Incorrect assay
temperature
Check that the incubation temperature was correct.
Use the Assay report to check the temperature.
Adjust the Assay protocol.
Microbiological
contamination of the
washer system
Clean and decontaminate the washer system
according to the description in the chapter
Maintenance. If necessary, change the tubing.
Inadequate washing
Ensure all wells are filled with wash buffer and are
being aspirated completely.
Check the washer dispenser functionality: flush the
wash head, clean the dispense needles with the
cleaning wire, if needed.
Check the washer aspiration functionality: Clean
aspiration needles with the cleaning wire, if needed.
Optimize the aspiration settings.
Contaminating
enzymes present in
sample
Test sample with substrate alone to check for
contaminating enzyme activity.
Reagents were
intermixed,
contaminated or
prepared incorrectly.
Ensure that the correct reagents have been used,
that working solutions were prepared correctly and
that contamination has not occurred.
Wash system
contained an alternate
wash solution
Be sure each unique wash solution is properly
labeled.
Prime the system thoroughly when switching wash
solutions.