Simulation of Isotopic Peak Patterns for High-Mass Oligomers and Polynuclidic Transition-Metal Salts

Abstract

An algorithm has been developed for rapidly and accurately simulating isotopic peak patterns of such diverse substances as mid- to high-mass-range peptides, e.g. bovine insulin (C₂₅₄H₃₇₇N₆₅O₇₅S₆) and ribonuclease (C₅₈₇H₉₀₉N₁₇₁O₁₉₇S₁₂), large polymerized hydrocarbons such as the styrene oligomer (C₈₀₄H₈₁₀), and polynuclidic transition-metal salts such as caesium tetrathiotungstate (VI) (Cs₂WS₄). The program requires less than 4 kb of random access memory (RAM); it is rapid, and not restricted by the size of the molecule ion. To calculate the experimentally observed peaks of bovine insulin within 2% error required 30 s on an IBM PC-XT 286 microcomputer fitted with a math coprocessor; similarly, all peaks of the styrene oligomer took 68 s on a Commodore 10-II personal computer. A fully documented, highly compact, version of the algorithm is available in either Fortran-77 or GW-Basic.