Olis DSM CD Service manual

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Turning on the Olis DSM CD
1Turn on the lamp cooling box.
2Turn 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.
3Turn on the power supply for the lamp.
4Press and hold the ignite button until lamp ignites. Ensure
that the current to the lamp does not exceed 7.5 Amps.
5Turn on the main power switch at the power strip.
4Turn on the computer and open GlobalWorks program.
5Select the Data Collection tab and double click on Conv CD.
6The 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. (AbsLeft-AbsRight)
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 cm2/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
1Open the Operational Modes tab and set the Data
Collection Mode to Scan.
2Ensure that the proper Data Reduction Mode is selected
(i.e., Circular Dichroism).
3Go to Live Display tab.
4Change Wavelength Scan Range to desired range.
5Click on Live Mode button and adjust PMT HV value to
give an acceptable signal (If you have photon counting
you cannot change PMT HV).
6Enter the desired number of increments to be collected
and the integration time for each point.
7Click on the Collect Data button to begin scan.
Taking repeated scans
1Under 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.
2Select Manual or Auto as the Scan Mode on this page.
3Ensure 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
1In the Repeated Scans tab, select the desired temperature
script by entering or browsing to the correct file.
2To edit a script file, click on Edit Script and change the
number of scans, temperatures and integration times.
3Check that the temperature controller is set to On in the
Temperature Control tab.
4In 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.
5Select appropriate data collection parameters in the Live
Display and Operational Modes tabs.
6Click on Collect Data to begin Scans.
Taking an assay
1Under the Operational Modes tab, set the Collection
Mode to Assay.
2Enter Total Assay Time in the Live Display tab.
3Set Current Wavelength to the desired assay wavelength.
4Enter Number of Points to Collect and Integration
Time per data point.
5To subtract an offset from the data, click on the Zero
Instrument button.
6To begin the assay, click on the Collect Data button and
press spacebar when prompted.
Collecting repeated scans as a
function of a titrator script
1In the Repeated Scans tab, set Repeat Scans as a
function of to Titrator Script.
2Follow instructions for calibration.
3Load solution into titrator using the Titrator Control
Panel to move syringes.
4To edit a script file, click on Edit Script.
5Select appropriate data collection parameters in the Live
Display and Operational Modes tabs.
6Click on Collect Data to begin Scans.
Quick Reference How-To Guide
for the Olis DSM CD Models

Saving a dataset
1Click on the desired dataset in the Experiment window.
2Add any comments, and change the dataset name if desired.
3Choose Save Dataset or Save dataset as… under the
File menu. Choose an appropriate directory and file name.
Saving an experiment
1Click on the desired experiment in the Experiment window.
2Choose Save Experiment under the File menu.
3The 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
1Highlight the desired data set in the experiment window,
2Left 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
1Select a data set to be exported.
2Right click on the chart and select Save as Ascii.
3Enter 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
1In the Experiment window, select a dataset by clicking on it.
2Right click on the dataset and choose Select.
3Repeat this procedure for any datasets to be included in
the mathematical operation.
4Right 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.
5The new mathematically manipulated dataset will be
generated in the Experiment window.
Converting CD units
1Select data by clicking on icon in Experiment window
and choosing Select.
2Right click again and choose Convert CD Units under
Data Processes.
3Choose the appropriate units.
Printing a data set as a report
1Select chart by clicking on dataset.
2Select Print Preview under File menu and choose Color
or Black and White.
3Click on Print.
Fitting 2-D data set
1Click on dataset to be fit.
2If 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.
3Select 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
1Select desired data set
2Right-click on graph
3Select scale and enter desired values.
Viewing more than one set of data
1Open all desired sets of data.
2Select a dataset to be viewed (move between data sets in
the Experiments window on the right).
3Select Copy Slice under Edit menu.
4Select second data set to view.
5Select 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
1In the Experiment window, select a dataset by
clicking on it.
2Right click on the desired dataset and choose Select
from the pop up menu.
3Right click on the dataset again and choose the Smooth
option under Data Processing in the pop up menu.
4Choose the degree of smoothing (3-25 points per average).
5A 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
1Click on the desired dataset in the Experiment window.
2Click on SVD to generate the SVD eigenvectors.
3Choose Reconstruct 3D from SVD Data.
Naming a dataset
1Double click on the Name property in the
Properties window.
2Enter a name for the dataset.
3Press enter to assign the name. This name will remain with the
dataset and is distinct from the file name.
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Pasting a dataset into Microsoft Word
1Select chart by clicking on dataset.
2Select Send Chart to Clipboard under Chart tab.
3Open Microsoft Word document.
4Choose Paste Special under Edit menu.
5Double click on graph to edit it using Microsoft Draw.
Turning off the DSM CD instrument
1Exit the GobalWorks software by selecting Exit under the
File menu.
2Exit Windows and turn off main power switch.
3Turn off power to lamp.
4Turn off nitrogen flow.
4Leave lamp cooling box on for a few minutes to help
cool the lamp.
Deleting a slice from a dataset
1Left click on a dataset to highlight it.
2Choose Edit Dataset under the Edit menu.
3Click on Edit Axis Data of the axis of the slice to remove.
4Left click axis points or drag mouse to select multiple points.
5Right click and select Remove Axis Points under
Axis Options.
6Click on Save Axis Data.
7Click Post Data to GlobalWorks.
Changing the axis titles on a dataset
1Left click on a dataset to highlight it.
2Choose Edit Dataset under the Edit menu.
3Change axis title and units. Axis values can be changed
by clicking Edit Axis Data, changing axis values, and
clicking Save Axis Data.
4Click Post Data to GlobalWorks.
Building a 3-D dataset
1Collect individual 2-D traces to be included in 3-D dataset.
2Click on dataset.
3Choose Edit Dataset under Edit menu.
4Change Y axis title and units to new axis.
5Repeat for each trace to be included. Cut and paste may
be used.
6Select all datasets to be included by right clicking each in
the Experiment window and choosing Select.
7Right click on a dataset in the Experiment window,
choose Build 3-D from 2-D under Data Processes.
8Select all datasets to be included by right clicking each in
the Experiment window and choosing Select.
9Click 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.
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