UNIGE document Scientific Article
previous document  unige:93531  next document
add to browser collection
Title

Exploring Fluorescent Dyes at Biomimetic Interfaces with Second Harmonic Generation and Molecular Dynamics

Authors
Cwiklik, Lukasz
Jungwirth, Pavel
Published in Langmuir. 2017, vol. 33, no. 14, p. 3373-3383
Abstract The adsorption of a DNA fluorescent probe belonging to the thiazole orange family at the dodecane/water and dodecane/phospholipid/water interfaces has been investigated using a combination of surface second harmonic generation (SSHG) and all-atomistic molecular dynamics (MD) simulations. Both approaches point to a high affinity of the cationic dye for the dodecane/water interface with a Gibbs free energy of adsorption on the order of −45 kJ/mol. Similar affinity was observed with a monolayer of negatively charged DPPG (1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol)) lipids. On the other hand, no significant adsorption could be found with the zwitterionic DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) lipids. This was rationalized in terms of Coulombic interactions between the monolayer surface and the cationic dye. The similar affinity for the interface with and without DPPG, despite the favorable Coulombic attraction in the latter case, could be explained after investigating the interfacial orientation of the dye. In the absence of a monolayer, the dye adsorbs with its molecular plane almost flat at the interface, whereas in the presence of DPPG it has to intercalate into the monolayer and adopt a significantly different orientation to benefit from the electrostatic stabilization.
Identifiers
Full text
Structures
Research group Groupe Vauthey
Citation
(ISO format)
LICARI, Giuseppe Léonardo et al. Exploring Fluorescent Dyes at Biomimetic Interfaces with Second Harmonic Generation and Molecular Dynamics. In: Langmuir, 2017, vol. 33, n° 14, p. 3373-3383. https://archive-ouverte.unige.ch/unige:93531

25 hits

0 download

Update

Deposited on : 2017-04-18

Export document
Format :
Citation style :