When using mass spectrometry to analyze samples containing unknowns, it is often necessary to derive elemental compositions (molecular formulas) for the unknowns based on the mass spectral data. For lower-mass compounds, accurate-mass measurements may be sufficient to produce a single, conclusive molecular formula or a small number of possible formulas. With increasing mass, however, the number of possible formulas increases dramatically. Additional constraints must be applied to reduce the list of candidate formulas to a manageable number. Agilent MassHunter Workstation software includes proprietary molecular formula generation (MFG) software. This software takes full advantage of the mass accuracy of the data, and then uses additional mass spectral information to logically narrow the list of possible formulas. It reduces ambiguity and delivers a list of candidate molecular formulas with scores based on the relative probability that each formula is the correct one. This significantly reduces data interpretation time and increases the value of accurate-mass analysis.
When analyzing samples containing unknowns, deriving elemental compositions based on mass spectral data is often necessary. For lower-mass compounds, accurate-mass measurements may be sufficient, but with increasing mass, the number of possible formulas increases dramatically. Agilent MassHunter Workstation software includes proprietary molecular formula generation (MFG) software that takes full advantage of mass accuracy and uses additional mass spectral information to logically narrow the list of possible formulas.
The MFG algorithms have been designed specifically to produce optimum results from accurate-mass data generated by Agilent 6200 Series Time-of-Flight and 6500 Series Quadrupole Time-of-Flight LC/MS systems. The software incorporates information such as isotope masses, abundances, spacing, user knowledge of sample composition, accuracy of mass measurements, and MS/MS fragment ions to generate a smaller list of candidate molecular formulas scored based on relative probability.
| Compatible Instruments | Agilent 6200 Series TOF and 6500 Series O-TOF LC/MS systems |
|---|---|
| Software Modules | MassHunter Workstation software, MassHunter Metabolite ID software, MassHunter Profiling software, GeneSpring MS software |
The software uses isotope masses, abundances and spacing; user knowledge of sample composition; accuracy of mass measurements; and masses of MS/MS fragment ions and neutral losses.
If molecular feature extraction (MFE) was used, the software combines the scores of related features such as adduct ions to achieve a cross score.