Bio-Tek ELx800, Operator'S Manual

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Liquid Testing
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Expected Results:
Since it is somewhat difficult to achieve high pipetting accuracy
when conducting linear dilutions, an R-Square value greater
than or equal to 0.990 is considered adequate.
Repeatability Test
1 Calculate the mean and standard deviation for the five readings
taken above at each concentration. Only one data set needs to be
analyzed for each concentration. The well that shows the most
variation for each concentration is selected for data reduction.
2 For each mean below 2.000 OD, calculate the allowed deviation
using the repeatability specification for a 96-well format of
± 0.5% ± 0.005 OD from 0.000 to 2.000 OD @ 405 nm.
3 The standard deviation for each set of readings should be less
than the allowed deviation.
For example:
Absorbance readings of 1.950, 1.948, 1.955, 1.952, and 1.950 will
result in a mean of 1.951, and a standard deviation of 0.0026. The
mean (1.951) multiplied by 0.5% (1.951 * 0.005) = 0.0098, which,
when added to the 0.005 (0.0098 + 0.005) = 0.0148 OD, which is
the allowable deviation. Since the standard deviation is less than
this value, the reader meets the test criteria.
Repeatability Specification:
For comparison in this test, the following repeatability spec is
applied, using Normal mode, 96-well microplate:
± 0.5% ± 0.005 OD from 0.000 to 2.000 OD @405 nm
ELx800 Operator's Manual