Surfactant self‐assembling in gas phase: electrospray ionization‐ and matrix‐assisted laser desorption/ionization‐mass spectrometry of singly charged AOT clusters

Bongiorno, David; Ceraulo̊, Leopoldo; Ruggirello, Angela; Liveri, Vincenzo Turco; Basso, Elisa; Seraglia, Roberta; Traldi, Pietro

doi:10.1002/jms.965

Cited by 36 publications

(58 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our negative ESI mass spectra of NaAOT aggregates show some differences than those reported by Bongiorno et al [10] and Giorgi et al [12]. Although solutions were prepared in a similar manner, their negative ESI mass spectra correspond to only monocharged [Na n-1 AOT n ]…”

Section: Formation Of Multiply Negatively Charged Naaot Aggregatescontrasting

confidence: 69%

“…In contrast with enormous work devoted to NaAOT aggregates in solution, only a handful of investigations have been reported concerning NaAOT aggregates as charged species in the gas phase [8][9][10][11][12][13][14][15][16], including electrospray ionization (ESI) and matrix-assisted laser desorption/ionization mass spectra [10,14], time-offlight secondary ion mass spectra [16] and infrared multiple photon dissociation spectra [13] of singly and doubly positively charged NaAOT aggregates. These measurements revealed reverse micelle-like structures for these aggregates.…”

mentioning

confidence: 99%

“…Bongiorno et al [10,48] and Giorgi et al [12] reported gas-phase negatively monocharged NaAOT aggregates. Bongiorno et al calculated the energy changes accompanying the formation of reverse and direct micelles for neutral, positively and negatively singly charged AOT trimers and found the electrostatic interactions among surfactant head groups are larger than apolar-apolar interactions among surfactant alkyl chains, which would favor a reverse micellar model for these trimers.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Mass Spectrometry Study of Multiply Negatively Charged, Gas-Phase NaAOT Micelles: How Does Charge State Affect Micellar Structure and Encapsulation?

Fang

Liu

2012

J. Am. Soc. Mass Spectrom.

View full text Add to dashboard Cite

Abstract. We report the formation and characterization of multiply negatively charged sodium bis(2-ethylhexyl) sulfosuccinate (NaAOT) aggregates in the gas phase, by electrospray ionization of methanol/water solution of NaAOT followed by detection using a guided-ion-beam tandem mass spectrometer. Singly and doubly charged aggregates dominate the mass spectra with the compositions of [Na n-z AOT n ] z-(n01-18 and z01-2). Solvation by water was detected only for small aggregates [Na n-1 AOT n H 2 O] -of n03-9. Incorporation of glycine and tryptophan into [Na n-z AOT n ] z-aggregates was achieved, aimed at identifying effects of guest molecule hydrophobicity on micellar solubilization. Only one glycine molecule could be incorporated into each [Na n-z AOT n ] z-of n≥7, and at most two glycine molecules could be hosted in that of n≥13. In contrast to glycine, up to four tryptophan molecules could be accommodated within single aggregates of n≥6. However, deprotonation of tryptophan significantly decrease its affinity towards aggregates. Collision-induced dissociation (CID) was carried out for mass-selected aggregate ions, including measurements of product ion mass spectra for both empty and amino acid-containing aggregates. CID results provide a probe for aggregate structures, surfactant-solute interactions, and incorporation sites of amino acids. The present data was compared with mass spectrometry results of positively charged [Na n+z AOT n ] z+ aggregates. Contrary to their positive analogues, which form reverse micelles, negatively charged aggregates may adopt a direct micelle-like structure with AOT polar heads exposed and amino acids being adsorbed near the micellar outer surface.

show abstract

Section: Formation Of Multiply Negatively Charged Naaot Aggregatescontrasting

confidence: 69%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Mass Spectrometry Study of Multiply Negatively Charged, Gas-Phase NaAOT Micelles: How Does Charge State Affect Micellar Structure and Encapsulation?

Fang

Liu

2012

J. Am. Soc. Mass Spectrom.

View full text Add to dashboard Cite

show abstract

“…The aggregation numbers for AA and MA were estimated using matrix assisted laser desorption ionization (MALDI) spectroscopy [18]. The spectra of the solutions were obtained at concentrations between the CMC and saturation.…”

Section: Aggregation Numbermentioning

confidence: 99%

Association (micellization) and partitioning of aglycon triterpenoids

Rafat

Fong

Goldsipe

et al. 2008

Journal of Colloid and Interface Science

View full text Add to dashboard Cite

“…In view of the recent interest for charged surfactant aggregates in the gas phase and in order to gain a more quantitative knowledge of the behavior of aqueous surfactant solutions under ESI conditions, we decided to carry out MD simulations of water nanodroplets containing the surfactant sodium bis(2‐ethylhexyl)sulfosuccinate (AOTNa). AOTNa is a well‐known di‐chained surfactant (see Fig.…”

Section: Introductionmentioning

confidence: 99%

Molecular dynamics of electrosprayed water nanodroplets containing sodium bis(2‐ethylhexyl)sulfosuccinate

et al. 2013

View full text Add to dashboard Cite

The behavior of aqueous solutions of sodium bis(2-ethylhexyl)sulfosuccinate (AOTNa) subject to electrospray ionization (ESI) has been investigated by molecular dynamics (MD) simulations at three temperatures (350, 500 and 800 K). We consider several types of water nanodroplets containing AOTNa molecules and composed of a fixed number of water molecules (1000), N(AOT)(0) AOT(-) anions (N(AOT)(0) = 0, 5, 10) and N(Na)(0) sodium ions (N(Na)(0) = 0, 5, 10, 15, 20): in a short time scale (less than 1 ns), the AOTNa molecules, initially forming direct micelles in the interior of the water nanodroplets, are observed in all cases to diffuse nearby the nanodroplet surface, so that the hydrophilic heads and sodium ions become surrounded by water molecules, whereas the alkyl chains lay at the droplet surface. Meanwhile, evaporation of water molecules and of solvated sodium ions occurs, leading to a decrease of the droplet size and charge. At 350 K, no ejection of neutral or charged surfactant molecules is observed, whereas at 500 K, some fragmentation occurs, and at 800 K, this event becomes more frequent. The interplay of all these processes, which depend on the values of temperature, N(AOT)(0) and N(Na)(0) eventually leads to anhydrous charged surfactant aggregates with prevalence of monocharged ones, in agreement with experimental results of ESI mass spectrometry. The quantitative analysis of the MD trajectories allows to evidence molecular details potentially useful in designing future ESI experimental conditions.

show abstract

Surfactant self‐assembling in gas phase: electrospray ionization‐ and matrix‐assisted laser desorption/ionization‐mass spectrometry of singly charged AOT clusters

Cited by 36 publications

References 14 publications

Mass Spectrometry Study of Multiply Negatively Charged, Gas-Phase NaAOT Micelles: How Does Charge State Affect Micellar Structure and Encapsulation?

Mass Spectrometry Study of Multiply Negatively Charged, Gas-Phase NaAOT Micelles: How Does Charge State Affect Micellar Structure and Encapsulation?

Association (micellization) and partitioning of aglycon triterpenoids

Molecular dynamics of electrosprayed water nanodroplets containing sodium bis(2‐ethylhexyl)sulfosuccinate

Contact Info

Product

Resources

About