List of common adducts observed for ESI-MS measurements in soft positive and negative ionization modes.
A data frame with 47 observations on the following 6 variables.
Equation for calculating adduct m/z from uncharged non-adduct molecular mass M (m/z = M/z + X)
Ionization mode (positive or negative)
Adduct chemical formula to be added
Adduct chemical formula to be subtracted
Factor to multiply chemical formula with
The correct way to calculate the isotopic pattern of a specific adduct is the following.
First, multiply the chemical formula of the molecule by the times it appears in the final adduct;
Second, add the chemical formula of any adduct to that of the molecule;
Third, subtract the chemical formula of any deduct from that of the molecule;
Finally, calculate the isotopic fine structure using the correct
charge argument in
Chemical formulas must conform to what is described in
Huang N., Siegel M.M., Kruppa G.H., Laukien F.H., J. Am. Soc. Mass. Spectrom. 1999, 10. Automation of a Fourier transform ion cyclotron resonance mass spectrometer for acquisition, analysis, and e-mailing of high-resolution exact-mass electrospray ionization mass spectral data
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# example of M+H adduct batch calculation data(adducts) data(isotopes) data(chemforms) # (1) check formulas for consistency - recommended checked_chemforms <- check_chemform(isotopes, chemforms) # (2) multiply, see column 4 of adducts chemforms <-multiform(checked_chemforms[,2],1) # (3) add adduct - see column 7 of adducts chemforms<-mergeform(chemforms,"H1") # (4) calculate fine structure patterns <- isopattern(isotopes, chemforms)