RATIONALE: The study of surfactant organization in vacuum allows surfactant–surfactant interaction to be unveiled inthe absence of surrounding solvent molecules. Knowledge on their chemical-physical properties may also lead to thedefinition of more efficient gas-phase carriers, air-cleaning agents and nanoreactors. In addition, the presence oflanthanide-group ions adds unique photochemical properties to surfactants.METHODS: The structural features, stability and fragmentation patterns of charged aggregates formed by lanthanide-functionalized surfactants, ytterbium and erbium bis(2-ethylhexyl)sulfosuccinate ((AOT) 3 Yb and (AOT) 3 Er), have beeninvestigated by electrospray ionization mass spectrometry (ESI-MS), tandem mass spectrometry (ESI-MS/MS) andenergy-resolved mass spectrometry (ER-MS).RESULTS: The experimental data indicate that the self-assembling of (AOT) 3 Yb and (AOT) 3 Er in the gas phase leads tothe formation of a wide range of singly charged aggregates differing in their aggregation number, relative abundance andstability. In addition to specific effects on aggregate organization due to the presence of lanthanide ions, ER-MSexperiments show rearrangements and in-cage reactions activated by collision, eventually including alkyl chain intra-cluster migration.CONCLUSIONS: Analysis of the experimental findings suggests that the observed chemical transformations occurwithin an organized supramolecular assembly rather than in a random association of components. The fragmentationpathways leading to the neutral loss of a fragment of nominal mass 534 Da, assigned as C 28 H 54 O 7 S, from some positivelycharged aggregates has been rationalized.
|Numero di pagine||8|
|Rivista||Rapid Communications in Mass Spectrometry|
|Stato di pubblicazione||Published - 2014|
All Science Journal Classification (ASJC) codes
- Analytical Chemistry
- Organic Chemistry