Biotek Synergy LX, User Manual

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Absorbance Testing | 72
Example: Five readings in well A1 of 0.802, 0.802, 0.799, 0.798, and 0.801 result in a
Mean of 0.8004 and a Standard Deviation of 0.0018. The Mean multiplied by 1.0%
(0.8004 * 0.01) equals 0.008, and when added to 0.005 equals 0.013; this is the Allowed
Deviation for well A1. Since the Standard Deviation for well A1 is less than this value, the
well meets the test criteria.
3. Calculate results for Linearity:
l
For each of the three test solutions, calculate the average Mean OD for the wells
containing that solution (mean of wells A1 to H2, A3 to H4, and A5 to H6).
l
Perform a regression analysis on the data to determine if there is adequate
linearity. The three average Mean OD values are the “Y” values. The solution
concentrations are the “X” values (1.00, 0.75, 0.50). Since it is somewhat difficult
to achieve high pipetting accuracy when conducting linear dilutions, an R2 value of
at least 0.9900 is considered adequate.
Troubleshooting
If an absorbance liquid test fails, try the following. If a test continues to fail, contact
Technical Support .
l
Check the microwells and plate carrier for debris that may have shifted and
caused changes.
l
Ensure the microplate is properly seated in the carrier.
l
As applicable, confirm that the plate was properly oriented in the "Normal" and
"Turnaround" positions.
l
Liquid Test 1 can fail due to the meniscus effect, which can cause readings to
decrease over time. If you suspect this may be the case, include a shake step
between the read steps in the protocol.
Synergy LX User Manual
1501000N Revision A BioTek Instruments, Inc.