Compared to carbon nanotubes, metal-oxide imogolite nanotubes (INT), with nominal composition (OH)3Al2O3SixGe1-x(OH), have the peculiarity to have a perfectly defined diameter D after their synthesis, combined to large aspect ratio L/D (L=nanotube length). This diameter can be tuned depending on the relative contents in Si and Ge. Imogolite nanotubes present a strong hydrophilic character (n-INT) but can be rendered hydrophobic. These methyl-modified nanotubes (m-INT) (OH)3Al2O3SixGe1-x(CH3) still present well defined diameter, tunable at the angstrom level, and represent an ideal custom-made system.The goal of this proposal is to investigate the dynamics of water confined into hydrophilic n-INT and hydrophobic m-INT with variable inner diameters (1.6 and 2.8 nm for n-INT; 1.8 and 2.4 nm for m-INT), in order to determine the respective roles of curvature effect and water-wall interactions.