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Bio-Rad Human MMP and TIMP Assays User Manual

Page 31

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Possible Causes

High Intra-Assay CV

Improper pipetting technique

Reagents and assay components
not equilibrated to room
temperature prior to pipetting

Contamination with wash buffer
during wash steps

Slow pipetting of samples and
reagents across the plate

Possible Solutions

Pipet carefully when adding
standards, controls, samples,
detection antibodies, and
streptavidin-PE, especially when
using a multichannel pipet. Use a
calibrated pipet. Change pipet tip
after every volume transfer.

All reagents and assay components
should be equilibrated to room
temperature prior to pipetting.


During the wash steps, be careful
not to splash wash buffer from one
well to another. Be sure that the
wells are filtered completely and that
no residual volume remains. Ensure
that the microplate shaker setting is
not too high. Reduce the microplate
shaker speed to minimize splashing.

Sample pipetting across the entire
plate should take less than 4 min.
Reagent pipetting across the entire
plate should take less than 1 min.