Atomistic Simulation of Solubilization of Polycyclic Aromatic Hydrocarbons in a Sodium Dodecyl Sulfate Micelle

Xujun Liang (1, 2) , Massimo Marchi (1, 2) , Chuling Guo , Zhi Dang , Stéphane Abel (1, 2)

1 I2BC - Institut de Biologie Intégrative de la Cellule
2 LBMS - Laboratoire Bioénergétique Membranaire et Stress

Solubilization of two polycyclic aromatic hydrocarbons (PAHs), naphthalene (NAP, 2-benzene-ring PAH) and pyrene (PYR, 4-benzene-ring PAH), into a sodium dodecyl sulfate (SDS) micelle was studied through all-atom molecular dynamics (MD) simulations. We find that NAP as well as PYR could move between the micelle shell and core regions, contributing to their distribution in both regions of the micelle at any PAH concentration. Moreover, both NAP and PYR prefer to stay in the micelle shell region, which may arise from the greater volume of the micelle shell, the formation of hydrogen bonds between NAP and water, and the larger molecular volume of PYR. The PAHs are able to form occasional clusters (from dimer to octamer) inside the micelle during the simulation time depending on the PAH concentration in the solubilization systems. Furthermore, the micelle properties (i.e., size, shape, micelle internal structure, alkyl chain conformation and orientation, and micelle internal dynamics) are found to be nearly unaffected by the solubilized PAHs, which is irrespective of the properties and concentrations of PAHs.

Domaines: Sciences du Vivant [q-bio]

Xujun Liang, Massimo Marchi, Chuling Guo, Zhi Dang, Stéphane Abel. Atomistic Simulation of Solubilization of Polycyclic Aromatic Hydrocarbons in a Sodium Dodecyl Sulfate Micelle. Langmuir, 2016, 32 (15), pp.3645--3654. ⟨10.1021/acs.langmuir.6b00182⟩. ⟨hal-02393985⟩