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International Interlaboratory Comparison of Mixtures of Polystyrenes With Different End Groups Obtained by Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS): Preliminary Results
Published
Author(s)
Charles M. Guttman, S Wetzel, Kathleen M. Flynn, B M. Fanconi, William E. Wallace, David L. VanderHart
Abstract
NIST has sponsored a MALDI-TOF-MS interlaboratory comparison of mixtures of polymers of the same repeat unit with closely matching molecular masses but with different end groups. This interlaboratory comparison was designed to see how well a group of labs from all over the world could get agreement on the percentages of each polymer that they found in a mixture of these polymers. In an earlier Interlaboratory Comparision , NIST studied the MMD and the moments of these on a PS and compared the results with classical methods.1 Polystyrenes of a molecular mass around 9000 with two different end groups were used. The Polystyrenes were both initiated with butyl initiator. One was terminated with an H (PSH) and the other was terminated with a CH2CH2OH (PSOH). Five mixtures of these were made up with mass ratios between approximately 95:5 to 10:90 PSOH: PSH. Samples of these mixtures were sent to any institution requesting it. A total of 14 institutions participated.
Proceedings Title
ASMS Confrence on Mass Spectrometry and Allied Topics | 52nd | Proceedings of the 52nd ASMS Confrence on Mass Spectrometry and Allied Topics | American Society for Mass Spectrometry (ASMS)
Guttman, C.
, Wetzel, S.
, Flynn, K.
, Fanconi, B.
, Wallace, W.
and VanderHart, D.
(2004),
International Interlaboratory Comparison of Mixtures of Polystyrenes With Different End Groups Obtained by Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS): Preliminary Results, ASMS Confrence on Mass Spectrometry and Allied Topics | 52nd | Proceedings of the 52nd ASMS Confrence on Mass Spectrometry and Allied Topics | American Society for Mass Spectrometry (ASMS), Nashville, TN, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=852364
(Accessed October 9, 2025)