Data processing tools
The MSD Productivity ChemStation and the MS workstation and MassHunter data analysis software provide complete mass spectral data processing application for the experienced operator, as well as for the inexperienced operator. Mass spectra can be viewed, tabulated, added, subtracted, and printed with just a click of the mouse. Mass spectra from the GC/MS systems of other manufacturers can be imported in tabular or AIA formats and processed.
Library searching
Commercial or user-created mass spectral libraries can be searched using the probability-based matching algorithm (PBM) included with the software. Optional search applications that can provide additional flexibility are available from third parties.
A variety of mass spectral libraries are available from Agilent:
| NIST 2008 MS Library |
General purpose |
220,000+ |
G1033A |
| Wiley 9th/NIST 2008 MS Library |
General purpose |
796,000+ |
G1035C |
| Stan Pesticides MS Library |
Pesticides |
340 |
G1038A |
| Maurer/Pfleger/Weber MS Library 2007 |
Drugs and metabolites |
7,840 data sets |
G1039D |
| Hazardous Chemicals RTL Library |
Environmental |
731 |
G1671AA |
| Pesticides RTL Library |
Pesticides and endocrine disrupters* |
926 |
G1672AA |
| Indoor Air Toxics RTL Library |
Environmental |
171 |
G1673AA |
| Forensic Toxicology RTL Library |
Forensic |
723 |
G1674AA |
| Japanese Positive List Pesticide RTL Library |
Pesticides |
431 |
G1675AA |
| Fiehn GC/MS Metabolomics RTL Library |
Metabolomics |
1,000+ |
G1676AA |
| Environmental Semi-Voas RTL Library |
Environmental |
273 |
G1677AA | *Mass spectra were collected on an Agilent 6890/5973 GC-MSD system under retention-time locked conditions.
If the compound you are looking for is not in a commercial library or if you would like to minimize the search time, you can create your own custom library. These can be created and edited using mass spectra acquired on other instruments or from other library sources.
Multiple libraries may be selected for sequential searching of unknown spectra. Default search criteria provide quality search results for most applications. However, in those cases where default values are not applicable, the software allows the operator to define the parameters used in the search.
The mass spectral PBM search result list returns the "hits" with the highest quality as defined by the search criteria. Scrolling through the list and selecting a compound will display the spectrum for that compound and the difference spectra of the unknown.
Chemical Structures
Chemical structures provide additional information that helps in detailed evaluation of the mass spectrum. The MSD ChemStation software supports chemical structure libraries in the .MOL format. Chemical structures with valid CAS numbers are automatically recalled and displayed with each searched spectrum. |