Metal Powder Substrate-Assisted Laser Desorption/Ionization Mass Spectrometry for Polyethylene Analysis
T Yalcin, William E. Wallace, Charles M. Guttman, L Li
We have developed a substrate-assisted laser desorption ionization (LDI) mass spectrometric method for polyethylene analysis where cobalt, copper, nickel, or iron metal powders are used as a sample substarte and silver nitrate is used as the cationization reaganet.a conventional UV LDI time-of-flight mass spectrometer, intact oligomeric ions having masses up to 5000 u were detected. Cobalt was found to produce spectra with the highest signal to noise ratio and the lowest level of fragmentation; furthermore, powder size was shown to have some effect on the spectra produced. The best results were obtained with the use of cobalt powder with particle diameters ranging from 30 mm to 100 mm. Fragmentation could not be totally eliminated; however, fragment ion peaks could be readily discerned from the intact polyethylene ions in the substrate-assisted LDI spectrum. The average molecular masses of low-mass polyethylene samples could be determined using this method.A rapid heating model is used to account for the effectiveness of using the coarse metal powders to assist the analysis of intact polyethylene molecules by LDI.
, Wallace, W.
, Guttman, C.
and Li, L.
Metal Powder Substrate-Assisted Laser Desorption/Ionization Mass Spectrometry for Polyethylene Analysis, Analytical Chemistry, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=852036
(Accessed March 4, 2024)