The Elemental Composition Workshop and the SearchFromList program provide powerful functions for examining mass spectra and assigning peaks or searching user-defined databases by using exact masses and isotopic abundances. These programs are not intended to replace the normal display and processing functions of a mass spectrometer data system for calibration, processing full chromatography/MS data sets, etc. Instead, the programs provide a means for identifying and labeling components in individual histogram mass spectra exported in a text format such as JCAMP-DX (*.jsp, *.jdx, etc.), NIST (*.msp) and Shrader (*.txt).

The MassSpecToMetafile program creates vector graphic (metafile) displays from mass spectra or mass chromatogram files saved in text format. The output can be imported into reports, presentations, or graphic editors for preparing publication-quality figures.

Programs

1. Mass Spec Periodic Table: Displays a periodic table with the information that is relevant to mass spectrometry. Clicking on an element produces a graphical display of the isotopic abundances for that element along with a table of exact masses and abundances for each element.

2. Isotope Ratio Calculator: More than just an exact-mass isotope ratio calculator, this program provides a means for simulating the isotopic abundances and masses average mass and the appearance of single-charge or multiple-charge isotopic clusters at any given resolving power. Overlapping isotopic clusters can be displayed, and isotopic enrichment can be modeled through user-defined isotopes. The calculation is fast and can be used to calculate the isotopic abundances and simulate peak shapes for large biomolecules.

3. Mass Series Calculator: Useful for calculating reference tables based on polymers or clusters with repeating subunits. The program can also calculate ionic clusters and multiple-charge ions (including multimers).

4. Elemental Composition Workshop: Calculate elemental compositions from exact masses, isotopic abundances, or both. The user can process individual masses or an entire spectrum. The results can be printed, saved to a file, or cut and pasted into a report. If the NIST Mass Spectral Database is installed, the program provides functions to search the database for candidate compounds by formula or name.

5. SearchFromList:This powerful program has many functions for searching exact-mass spectra against a custom mass spectral database or identifying components in a complex spectrum by exact mass measurements. The user can create lists of target compounds in comma-delimited text or Microsoft Excel format. Both absolute (target compound) and relative (e.g. metabolite or adduct) mass lists can be created. User-defined series can be defined to search a spectrum for polymer repeat units, clusters, adducts, alkyl series or silyl derivatives. A measured spectrum can be searched against a mass spectral database consisting of text-format mass spectra stored in a user-specified directory on the disk. Additional functions include spectrum comparison, spectrum addition and subtraction and Kendrick Mass Defect analysis. An optional Access database can be used to enter or look up detailed information about a given mass spectrum in a user-created mass spectral database

6. Mass Spec to Metafile: This program takes as input a text-format mass spectrum (profile or histogram) or chromatogram and creates a vector graphic (metafile) that can be cut and pasted into a report or presentation for further editing. The user can specify the mass axis range and the spacing between m/z tic marks and labels. Large fonts are used for clarity.

7. Simple ESI Calculator: Calculate multiple-charge ion m/z's for a given composition, or estimate molecular weight from two successive charge states or a measured m/z and a known adduct.

8. Interactive Peak Integrator: Permits manual peak integration for text-format chromatograms or peaks in a segment of a mass spectrum.

9. PPMCalc:Interactively view the relationship between parts-per-million, resolving power, and mass differences.

10. Batch Composition to Mass Converter: Rapid calculation of monoisotopic average, nominal, and/or lowest m/z for large compound lists. Can convert elemental thousands of elemental compositions in spreadsheet form within seconds.

11. Subtract Composition: Subtract one elemental composition from another and view the resultant composition and masses for each composition. Useful for thinking through problems involving fragmentation or finding the remaining "core" group for compounds with polymeric components.

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