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Kinetics Parameter 1 Screen
Step 1
Set Wavelength. Enter all numerical values using the
keypad numbers or the left and right arrows.
Press the down arrow key.
Step 2
Enter the delay time in seconds before
measurements are taken. This can be a maximum of
600 seconds (10 minutes).
Press the down arrow key.
Step 3
Enter the duration in minutes over which
measurements are taken. This can be a maximum of
60 minutes.
Press the down arrow key.
Step 4
Enter the interval time in seconds between
measurements using the left and right arrows.
Options are: 5, 10, 20, 30 or 60 seconds.
Step 5
Press Next
to go to the next parameters
screen or press Cancel
to return to the
Applications Folder.
Kinetics Parameters 2 Screen
Step 6
Select the measurement mode using the left and
right arrows.
Delta A:
change in absorbance over the
measurement duration (or selected period).
Final A:
absorbance at the end of the measurement
duration (or selected time).
Slope:
rate of change of absorbance over the
measurement duration or selected period.
Press the down arrow key.
Simple Kinetics
Kinetics studies, where the change in absorbance needs to be followed as a function of time at a fixed wavelength, can be
readily performed.
Reagent test kits are routinely used for the enzymatic determination of compounds in food, beverage and clinical
laboratories by measuring NAD / NADH conversion at 340 nm. The change in absorbance over a specified time period
can be used to provide useful information when an appropriate factor, defined in the reagent kit protocol, is applied.
Reaction rate and enzyme activity can be calculated if the factor used takes account of the absorbance difference per unit
time, as opposed to the absorbance difference
per se
.
For this reason, the change in absorbance per minute
(ΔA/min
), concentration (
ΔA/min x factor
) and
correlation
coefficient
(calculated from a best fit of the data points) are displayed. They may not be relevant for simple kinetics
experiments.
The procedure to define a new method is as follows:
