Easy ways to create custom figures from GPC/SEC data
In a previous post I described how to create the perfect figure for your data using the OMNISEC v10+ and OmniSEC v5 software platforms. While those figures are excellent for displaying chromatograms in documents and presentations, sometimes it is helpful to use the data to generate your own plots. If you are preparing a journal manuscript for submission, you may have limited space or color options available.
In this post, I’ll discuss how to extract the collected data points so you can use them to create custom figures in your spreadsheet program of choice. Whether you use OMNISEC v10+ with an OMNISEC system or REVEAL unit or OmniSEC v5 with our SEC-MALS 20, this post has you covered.
Selecting the data to copy in OMNISEC v10+
The first step to extracting data is to open the corresponding injection. Once you have the data open, determine what type of data do you want to transfer into a spreadsheet. For instance, do you want to recreate the chromatogram? Do you want to superimpose any of the calculated results (e.g. molecular weight, IV, Rh, etc.) on top of the sample peak? Is an overlay plot what you have planned?
This consideration is important because the data available for extraction depends on the plot from which it is copied. The data comprising the raw data chromatograms can be copied from the Raw Data window. Any calculated results, along with baseline-subtracted detector responses, are available from the Derived Data window. Overlay and Derived Data windows contain the data to generate those figures, respectively.
Copying data from OMNISEC v10+
Once you know which type of data you wish to copy into a spreadsheet or other software package, there are three easy methods to copy said data.
First, you can right click on the plot containing the desired data and select Copy data, as shown below.
Second, ensure the plot containing the desired data is the active window. You can tell because the header of the active window will be green (or other color depending on your chosen color theme). At that point, all you need to do is click the Copy data button in the Calculation section of the main tool bar.
A third way to copy the plot data is through the report widget. If you have the desired figure type included in a report, you click on the three dot menu icon in the top right (step 1 below), then choose the top icon indicating Copy data (step 2 below).
At this point, you simply open your spreadsheet and paste in the copied data. Be warned – the spreadsheet will contain every data point for all data sets available in that window!
Extracting data from OmniSEC v5
Similar to OMNISEC v10+, in OmniSEC v5 you can extract raw data, calculated results, overlay or distribution plots, etc. from an individual figure by right clicking and selecting Copy data. In this case you need to be conscious of the particular figures on which you are clicking, as not all data is available from each.
An alternative method that will ensure all data is captured is to open the data file of interest, then navigate to File > Export! If you have saved results associated with the data file, this will copy the raw data and the calculated results (against retention volume, i.e. not distribution plots) and save them all in a text file located in the same folder as the data. You can then open the text file using a spreadsheet program and have all data available for further manipulation.
Final thoughts
In conclusion, I hope the tips included here allow you to generate the perfect figures for illustrating your data. If you have any questions, please don’t hesitate to contact us or email me directly at kyle.williams@malvernpanalytical.com.
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