IsotopeCalculator 2 – Compute Isotopic Distributions for Large Proteins

IsotopeCalculator 2


IsotopeCalculator is a  memory efficient algorithms for accurately calculating the isotopic fine structures of molecules. Treating individual isotopic species of a molecule as different mass states, we introduce the concept of transitions between mass states and represent all mass states of the molecule in a hierarchical structure. We show that there exists a simple relationship between two different mass states at two different levels of the hierarchical structure. This allows us to efficiently and accurately compute both the mass and the abundance of every mass state of a small to medium-sized molecule, whose gross structures include small number of fine structures. A truncated calculation of this algorithm can be applied to calculate a majority of isotopic species (99.99% of cumulative abundance) of a large molecule.


Pengyu Hong




  • Windows/Linux/MacOsx





Li L., Karabacaka N. M., Cobba J. S., Wang Q., Hong P*, Agara J.N.*.
Memory Efficient Calculation of the Isotopic Mass States of a Molecule.
Rapid Commun Mass Spectrom. 2010 Sep;24(18):2689-96.

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