Building up nanotubes: docking of "Janus" cyclodextrins in solution.
Using molecular dynamics experiments, we analyze the association of "Janus" 6-amino-6-deoxy-2O-carboxymethyl-beta-cyclodextrins (JCD) in aqueous solutions. In JCD dimers, the free energy associated with the primary-rim-secondary-rim docking shows a stable minimum of approximately -45 kcal mol(-1). Trimers in solution are also remarkably stable, exhibiting minimal distortions in their spatial and orientational distributions. The resulting geometrical docking shows the incipient characteristics of flexible nanotubes in solution, with eventual water interchange between the central channel and the bulk at the junctions between monomers. Structural and dynamical properties of the trapped water filling the nanotube are dictated to a large extent by the charge density at the rims.
Rodriguez
Javier
J
Departamento de Fisica de la Materia Condensada, Comision Nacional de Energia Atomica, Av. Gral. Paz 1499, (1650) San Martin, Prov. de Buenos Aires, Argentina. javier@speedy.cnea.gov.ar
Semino
Rocío
R
Laria
Daniel
D