Bio-Rad Microplate Manager Software - Manual (Page 64)

Running Kinetic Assays
56
After the read is completed, data can be excluded from calculation by defining a new
time range or new OD range. Original data is not lost, but is not included in the
current calculation.
Defining Kinetic Parameters
Several alternative kinetic parameters can be used for analyzing the raw kinetics data
in the program:
• Rate - The kinetic rate (slope of the OD vs. time curve) will be calculated
by linear regression, using all the data points within the selected OD and
time range.
Set time or OD cutoffs on the data, to exclude part of the data from the
analysis. This is useful for excluding an initial lag time in delayed reactions
or for excluding the end of a reaction where the reaction approaches
equilibrium.
For reactions where the OD values decrease with time, the rates will appear
as negative values (negative kinetics). To change the values to positive
numbers, apply the transformation -1*@ to the data.
• Maximum Rate - The Maximum Rate option is useful, as an alternative to
selecting the linear part of the curve using OD and time limits. In the
Maximum Rate method, the OD vs. time curve is segmented and a series of
linear curve fits are performed in order to determine the maximum rate.
The first segment starts at the first data point within the selected time and
OD range, the second segment starts at the second data point, etc. The
maximum rate is determined by evaluating all of these rate calculations.
The number of data points included in a segment is specified by the user
(# of points). If the # of points is equal to or higher than the total number of
data points within the selected OD and time range, a single regression will
be performed using all valid data points.
For cases where the OD values decrease with time (negative kinetics) the
rate values will be negative. To change the sign of negative values, apply
the transformation -1*@ to the data.