User`s manual

64 Chapter 6: Sample Experiments
Calorimetry Sciences Corp.
CSC 5300 N-ITC III 65
User’s Manual
Blank Titration
The heat effect measured in a titration experiment includes the heat of dilution of the
titrant, in addition to the heat generated from the binding reaction. In order to correct
for the dilution heat, a blank experiment is performed which is identical to the binding
experiment, but with buffer only present in the cell.
Set up a titration control le with twenty 5 μL injections using a 200 s equilibration time
and 200 s between injections (parameters should be identical to the sample experiment).
Load the syringe with 2’-CMP. When the calorimeter has re-equilibrated, begin a
titration.
Results
The graph will appear similar to that shown in Figure 6-5. The data generated in a
titration experiment takes the form of power (µW) as a function of time (seconds). In or-
der to analyze the data we want to know heat as a function of the number of injections (or
moles of added ligand). This form of the data is obtained by integrating the peaks from
the experiment.
To begin, start the data analy-
sis program BindWorks. Next,
select File⇒Open from the
main menu, then select the
data le you wish to analyze.
Select the Raw Data tab from
the program main screen
and click the Show Zoom
Window and Baseline but-
tons (Figure 6-6). Adjust the
default base lines used to inte-
grate the data if required.
After integration is complete,
select the Area tab from the
Figure 6-5: Typical data output from RNase A titration
experiment.