page 1
Turning on the Olis DSM CD
1 Turn on the lamp cooling box.
2 Turn on the nitrogen flow to the lamp and
monochromator to at least 6 L per min. Higher flow rates
in the monochromator should be used if data are to be
taken before 200 nm.
3 Turn on the power supply for the lamp.
4 Press and hold the ignite button until lamp ignites. Ensure
that the current to the lamp does not exceed 7.5 Amps.
5 Turn on the main power switch at the power strip.
4 Turn on the computer and open GlobalWorks program.
5 Select the Data Collection tab and double click on Conv CD.
6 The spectrophotometer will initialize and calibrate.
Changing CD units of data collection
‰
One may choose from several units of data collection in
the Parameters tab under CD Units.
Milliabsorbance: Reports data as the difference in
absorbance of left circularly polarized light and right
polarized light. (Abs
Left
-Abs
Right
)
Molar Extinction: Reports the difference in extinction
coefficients for left and right polarized light. ((
Left-(Right
)
Millidegrees: Reports ellipticity in units of millidegrees..
Molar Ellipticity: Reports molar ellipticity in units of
deg cm
2
/dmol. The user must provide the program with protein
concentration (g/L), cell pathlength (cm), and mean residue
weight (g/mol).
Taking a wavelength scan
1 Open the Operational Modes tab and set the Data
Collection Mode to Scan.
2 Ensure that the proper Data Reduction Mode is selected
(i.e., Circular Dichroism).
3 Go to Live Display tab.
4 Change Wavelength Scan Range to desired range.
5 Click on Live Mode button and adjust PMT HV value to
give an acceptable signal (If you have photon counting
you cannot change PMT HV).
6 Enter the desired number of increments to be collected
and the integration time for each point.
7 Click on the Collect Data button to begin scan.
Taking repeated scans
1 Under Repeated Scans tab, change Number of Scans
to the desired number. Scans can be made automatically
as a function of time, or manually. In the
Auto mode, the
time selected is the total time to complete all scans. In the
Manual mode, scans are started by pressing the spacebar.
2 Select Manual or Auto as the Scan Mode on this page.
3 Ensure that Time Units are correct. These can be
changed in the Operational Modes tab.
‰
All repeated scan data will be saved as a single, 3-D data set.
‰
Selecting Average Scans results in an output of a single,
averaged scan.
Taking repeated scans as a function
of a temperature script
1 In the Repeated Scans tab, select the desired temperature
script by entering or browsing to the correct file.
2 To edit a script file, click on Edit Script and change the
number of scans, temperatures and integration times.
3 Check that the temperature controller is set to On in the
Temperature Control tab.
4 In the Repeated Scans tab, set Repeat Scans as a
function of to Temperature Script. The Number of
Scans value should change to be equal to the number of
scans in the temperature script.
5 Select appropriate data collection parameters in the Live
Display and Operational Modes tabs.
6 Click on Collect Data to begin Scans.
Taking an assay
1 Under the Operational Modes tab, set the Collection
Mode to Assay.
2 Enter Total Assay Time in the Live Display tab.
3 Set Current Wavelength to the desired assay wavelength.
4 Enter Number of Points to Collect and Integration
Time per data point.
5 To subtract an offset from the data, click on the Zero
Instrument button.
6 To begin the assay, click on the Collect Data button and
press spacebar when prompted.
Collecting repeated scans as a
function of a titrator script
1 In the Repeated Scans tab, set Repeat Scans as a
function of to Titrator Script.
2 Follow instructions for calibration.
3 Load solution into titrator using the Titrator Control
Panel to move syringes.
4 To edit a script file, click on Edit Script.
5 Select appropriate data collection parameters in the Live
Display and Operational Modes tabs.
6 Click on Collect Data to begin Scans.
Quick Reference How-To Guide
for the Olis DSM CD Models
Saving a dataset
1 Click on the desired dataset in the Experiment window.
2 Add any comments, and change the dataset name if desired.
3 Choose Save Dataset or Save dataset as… under the
File menu. Choose an appropriate directory and file name.
Saving an experiment
1 Click on the desired experiment in the Experiment window.
2 Choose Save Experiment under the File menu.
3 The program will prompt for file names for each data set
in the experiment. When the experiment is reopened all
the accompanying datasets will be opened.
Assigning a baseline
1 Highlight the desired data set in the experiment window,
2 Left click on the data to select it and then right click on the
data and select Assign as Baseline. The baseline will continue
to be applied until the wavelength range, number of data
points, or Assign baseline checkbox have been changed.
Exporting a 2-D data set
1 Select a data set to be exported.
2 Right click on the chart and select Save as Ascii.
3 Enter the filename when prompted.
‰
Alternatively, data can be exported directly into Excel by
selecting Export to Excel under the right-click menu.
Doing math on a dataset
1 In the Experiment window, select a dataset by clicking on it.
2 Right click on the dataset and choose Select.
3 Repeat this procedure for any datasets to be included in
the mathematical operation.
4 Right click on the dataset again and choose the desired
mathematical operation under the Data Processing menu.
These options are also available under the Tools menu.
5 The new mathematically manipulated dataset will be
generated in the Experiment window.
Converting CD units
1 Select data by clicking on icon in Experiment window
and choosing Select.
2 Right click again and choose Convert CD Units under
Data Processes.
3 Choose the appropriate units.
Printing a data set as a report
1 Select chart by clicking on dataset.
2 Select Print Preview under File menu and choose Color
or Black and White.
3 Click on Print.
Fitting 2-D data set
1 Click on dataset to be fit.
2 If you desire to fit only a portion of this data, select
Create Data Subset in the Tools menu. When prompted,
enter the desired range. Click on new dataset to select it.
3 Select 2-D Fits under the Fits menu and select the
desired model to fit the data. If you would like a data
fitting model added to the software, please contact Olis.
Fitting a 3-D data set
‰
There is a tutorial under the Help menu which describes
SVD data processing and fitting.
Changing the axis scale on a data set
1 Select desired data set
2 Right-click on graph
3 Select scale and enter desired values.
Viewing more than one set of data
1 Open all desired sets of data.
2 Select a dataset to be viewed (move between data sets in
the Experiments window on the right).
3 Select Copy Slice under Edit menu.
4 Select second data set to view.
5 Select Paste Slice under Edit menu
‰
To hide a slice from view (and from the printer), select it
and select Hide Slice under the View menu.
‰
To switch between hidden slices and viewed slices, select
Swap Hidden/Unhidden Slices under View menu.
Smoothing a scan
1 In the Experiment window, select a dataset by
clicking on it.
2 Right click on the desired dataset and choose Select
from the pop up menu.
3 Right click on the dataset again and choose the Smooth
option under Data Processing in the pop up menu.
4 Choose the degree of smoothing (3-25 points per average).
5 A new smoothed dataset will be generated in the
Experiment window. The name will by default be
“[original data file name]-smoothed.”
Smoothing a 3D dataset using SVD
1 Click on the desired dataset in the Experiment window.
2 Click on SVD to generate the SVD eigenvectors.
3 Choose Reconstruct 3D from SVD Data.
Naming a dataset
1 Double click on the Name property in the
Properties window.
2 Enter a name for the dataset.
3 Press enter to assign the name. This name will remain with the
dataset and is distinct from the file name.
page 2
Pasting a dataset into Microsoft Word
1 Select chart by clicking on dataset.
2 Select Send Chart to Clipboard under Chart tab.
3 Open Microsoft Word document.
4 Choose Paste Special under Edit menu.
5 Double click on graph to edit it using Microsoft Draw.
Turning off the DSM CD instrument
1 Exit the GobalWorks software by selecting Exit under the
File menu.
2 Exit Windows and turn off main power switch.
3 Turn off power to lamp.
4 Turn off nitrogen flow.
4 Leave lamp cooling box on for a few minutes to help
cool the lamp.
Deleting a slice from a dataset
1 Left click on a dataset to highlight it.
2 Choose Edit Dataset under the Edit menu.
3 Click on Edit Axis Data of the axis of the slice to remove.
4 Left click axis points or drag mouse to select multiple points.
5 Right click and select Remove Axis Points under
Axis Options.
6 Click on Save Axis Data.
7 Click Post Data to GlobalWorks.
Changing the axis titles on a dataset
1 Left click on a dataset to highlight it.
2 Choose Edit Dataset under the Edit menu.
3 Change axis title and units. Axis values can be changed
by clicking
Edit Axis Data, changing axis values, and
clicking Save Axis Data.
4 Click Post Data to GlobalWorks.
Building a 3-D dataset
1 Collect individual 2-D traces to be included in 3-D dataset.
2 Click on dataset.
3 Choose Edit Dataset under Edit menu.
4 Change Y axis title and units to new axis.
5 Repeat for each trace to be included. Cut and paste may
be used.
6 Select all datasets to be included by right clicking each in
the Experiment window and choosing Select.
7 Right click on a dataset in the Experiment window,
choose Build 3-D from 2-D under Data Processes.
8 Select all datasets to be included by right clicking each in
the Experiment window and choosing Select.
9 Click on the new dataset, choose Edit Dataset under the
Edit menu.
10 Choose Edit Axis Data, enter new values and click Save
Axis Data.
11 Click Post Data to GlobalWorks.
page 3
page 4
Loading...