Scientific Publications by FDA Staff

Biol Mass Spectrom 1975 Oct;2(5):276-8

Mass spectrometry in toxicology: I - calculation of theoretical isotopic abundances and optimum ion dwell time for a 2,3,7,8-tetrachlorodibenzo-p-dioxin pharmacokinetic study

Reynolds WD, Delongchamp R

2,3,7,8-Tetrachlorodibenzo-p-dioxin and 2,3,7,8-tetrachlorodibenzo-p-dioxin-13C12 parent ion isotope cluster abundances are calculated on a multinomial probability basis for all possible isotope combinations. Parent negative ions at m/e 322 and m/e 334 were selected for dual ion monitoring in the isotope dilution technique. Calculations, according to the Jaech's Method, are given for optimizing dual ion monitoring dwell time in the pulse counting mode at the femtogram level.