Water Encapsulation by Nanomicelles

Abstract

Reported is the hydration of nanomicelles in the gas-phase using spectroscopic methods and quantum chemical calculations. A fine-tuning of the experimental conditions allowed formation of a propofol trimer and tetramer with a water molecule and to determine the structure of the aggregates. Their electronic and IR spectra were obtained using mass-resolved laser spectroscopy, together with the number of conformational isomers for each stoichiometry. Interpretation of the spectra in the light of high-level calculations allowed determination of the cluster's structure and demonstration that the trimer of propofol with a water molecule forms cyclic hydrogen-bond networks but, on the other hand, the tetramer is big enough to encapsulate the water molecule inside its hydrophilic core. Furthermore, these hydrated nanomicelles present an unusually high binding energy, thus reflecting their high stability and their capability to trap water inside.

Phenyl-β-D-glucopyranoside and Phenyl-β-D-galactopyranoside Dimers: Small Structural Differences but Very Different Interactions

“…Therefore, to ensure that no important structures were left out, the same computational procedure already tested successfully for similar systems was used [6,[40][41][42]. It consisted of three stages.…”

“…Note that the only difference between both monosacharides is the relative position of the O4H hydroxyl group. such as amino acids or peptides [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21], neurotransmitters [22][23][24][25][26][27][28], anesthetics [29,30], several mono-, di-and poly-saccharides [4,6,[31][32][33][34][35][36][37][38][39] or even micelles [40][41][42]. In these systems, the addition of a chromophore with an optically accessible excited electronic state is required to probe the molecules.…”

The evolution towards cyclic structures in the aggregation of aromatic alcohols: the dimer, trimer and tetramer of 2-phenylethanol

“…The extension of the molecular size is challenging because of the growing spectral congestion and computational difficulties, but permits following the emergence of molecular-scale patterns, such as nanomicelles. 18,23,24 Furthermore, interesting modulations in non-covalent interactions can be achieved by combination of additional chemical groups, like heteroatoms or aliphatic rings, paving the way for the rational design of macromolecular entities. 25,26 For aliphatic compounds, we developed a new laser technique that combines ns and fs laser sources to record mass-resolved IR spectra of molecules without chromophore.…”

Propofol adsorption at the air/water interface: a combined vibrational sum frequency spectroscopy, nuclear magnetic resonance and neutron reflectometry study

“…This is in contradiction to what has been inferred in gas-phase where "nano-micelles" containing several multimers of propofol were found. 55 In addition, the NMR intensity was proportional to the concentration in the whole range which also excludes the presence of any large aggregates (for which the NMR signal could possibly be lost).…”