0000000000607951
AUTHOR
S. Indelicato
Degrees of freedom effect on fragmentation in tandem mass spectrometry of singly charged supramolecular aggregates of sodium sulfonates
The characteristic collision energy (CCE) to obtain 50% fragmentation of positively and negatively single charged noncovalent clusters has been measured. CCE was found to increase linearly with the degrees of freedom (DoF) of the precursor ion, analogously to that observed for synthetic polymers. This suggests that fragmentation behavior (e.g. energy randomization) in covalent molecules and clusters are similar. Analysis of the slope of CCE with molecular size (DoF) indicates that activation energy of fragmentation of these clusters (loss of a monomer unit) is similar to that of the lowest energy fragmentation of protonated leucine-enkephalin. Positively and negatively charged aggregates be…
Collision induced fragmentations of multiply charged sodium bis(2-ethylhexyl)-sulfosuccinate aggregates in gas phase: neutral loss versus charge separation
Abstract Stability and fragmentation patterns of multicharged aggregates of sodium bis(2-ethylhexyl)-sulfosuccinate (NaAOT) in gas phase have been investigated by ion mobility mass spectrometry (IM-MS) and tandem mass spectrometry (MS-MS). Positively doubly charged NaAOT aggregates show at low collision energy a preference for the loss of NaAOT molecules, whereas fragmentation through charge separation process is favored at higher collision energy. By increasing the charge state of the aggregates, the fragmentation through charge separation tends to predominate especially at low aggregation number and only charge separation fragmentation is observed for positively quadruply charged species.…
Occurrence and transformation of illicit drugs in wastewater treatment plants.
Illicit drugs (IDs) and their metabolites have been recently recognized as a new group of water emerging contaminants (ECs) with potent psychoactive properties and unknown effects to the aquatic environment (Pal et al., 2013). IDs are excreted via urine and feces and arrive at wastewater treatment plants (WWTPs) where can reach ppb levels (Castiglioni et al., 2006). Over the past few years, it has been demonstrated that conventional biological processes in WWTPs are not or scarcely able to remove IDs. Thus, they are discharged into water bodies through the treated effluent (Postigo et al., 2011). Therefore, monitoring the IDs concentration in WWTPs can have a twofold advantage: i. increase …