This project contains a database which classifies polymer structures according to their repeat unit masses, as obtained by MALDI ToF measurements
This project contains a database which classifies polymer structures according to their repeat unit masses, as obtained by MALDI ToF measurements
The MALDI Polymer Structure Finder consist of a simple Excel file that contains 3 sheets
Mask, Values and Data
This is the search screen.
Here the ‘unknown’ peak distance can be inserted in the corresponding field (left hand side). Please notice: Since some mass spectrometers do not have sufficient resolution in higher mass ranges, and/or calibration might be slightly wrong only insert integer numbers. Any use of comma or decimal point results in no match.
A short visual explanation is also given underneath the result fields.
In those cases, where no match was found, the polymer structure with the closest lower mass number is displayed in the 1st (left) result field.
The field #References# contains the URL of available original literature related to the match. This link automatically leads you (depending on the accessibility, see specific rules of your organisation) to the publisher of the literature. In case where more than one reference is displayed, the automatic redirection does not work. Here, the reference links should be copied/pasted one by one in the address line of a web browser.
The Values sheet contains information and variables neccesary to display multiple entries.
For example, mass 58 can be polypropylene glycol, but also polyglycolide. Mass 100 may represent three different polymer structures PMMA, PVL or PIBVE.
It contains the whole information to run the Finder.
Included are 90 data sets of published polymer structures combining
The import of structure data and corresponding structure figures requires the use of an (with costs !) Excel add-on called Image-xls (agindo GmbH). This must be installed on your computer before.
Typically, every import of new structures starts with adding a name, mass number etc. in a new line at the end of the data base.
Then, a sorting must be performed according to increasing rounded mass numbers (without header line).
This is usually followed by drawing the new structure figure, which has to be stored in the structures folder. The link to this structure must be filled in the empty cell in column O. Then start Image-xls. The new structure will appear in column P.
In case you add a structure with a mass number that already exist in the table, please check that columns A and B in Data will be updated accordingly. Normally, this should proceed automatically. If not, Values will calculate wrong line numbers and wrong structures will be attributed to those masses. One can easily check this in values cells A13/C13/E13.
I’d like to ask everyone to let me know, when new structures were added, or even better, let me do this. This enables a permanent updates of the data base and accessibility of the new data for everyone.
You can contact me via: steffen.weidner[at]bam.de or create an issue here on GitHub.