The chromatographic and mass spectral characteristics of perfluorooctanesulfonate (PFOS) and three nitrogen-substituted perfluorooctanesulfonamides have been obtained. A methyl/phenyl mixed-phase fused-silica capillary column was used for gas chromatographic (GC) analyses, while a C18 reversed-phase microbore column was used for liquid chromatographic (LC) analyses. Mass (MS) and tandem mass (MS/MS) spectra were generated using electron ionization (EI), argon CE, methane positive and negative ion CI, and ES ionization modes. EI spectra of the amides showed ions characteristic of both the fluorinated hydrocarbon and the sulfonamide portion of the molecules. The fragmentation pathway was studied using hydrogen/deuterium exchange, and was thought to involve a cyclic intermediate ion. Formation of molecular ions by CE and protonated molecule ions by CI to obtain molecular weight information was only partially successful. Negative ion ES-MS spectra provided intense [M-H] À anions for the amides, and an [M-K] À anion for PFOS from which molecular weight information could be obtained, while ES-MS/MS produced product ions that could be used to detect the presence of these compounds in biological or environmental samples. Published in

S-Aminoethylated-alpha A and -beta A globin tryptic peptides separated by reversed-phase high-performance liquid chromatography have been analysed by plasma desorption mass spectrometry. Almost all the expected alpha A and beta A tryptic fragments were tentatively assigned relative to the known globin chain sequences based on the molecular weight obtained by plasma desorption mass spectrometric analysis of the purified peptides. The application of plasma desorption mass spectrometry for structure elucidation of a haemoglobin alpha-chain variant revealed the first case of Hb Hasharon in Hungary.

The influence of ganglioside GM3 and some of its breakdown products on phytohemagglutinin‐induced blast transformation of human lymphocytes and concanavalin‐A‐induced T‐suppressor activity was studied. The structures of two major hydrolysis products of GM3 were established by negative‐ion fast‐atom‐bombardment mass spectrometry as neuraminyllactosylsphingosine (NeuLacSph) and neuraminyllactosylceramide (NeuLacCer). Both substances were shown to be potent inhibitors of mitogen‐induced lymphoblastic transformation whereas their acetylation products NeuAcLacSphAc and GM3 did not affect the proliferative response of lymphocytes to phytohemagglutinin. On the other hand, only GM3 and NeuLacSph were able to enhance concanavalin‐A‐induced T‐suppressor activity. On the basis of these data, it is suggested that the effects of GM3 and its breakdown products on lymphoblastic transformation and T‐suppressor activity must rest on different mechanisms and that N‐deacylation of GM3 appears to be an essential step in conversion of the ganglioside into an inhibitor of lymphocyte blast transformation.

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