We report the preparation of a novel type of mesoporous silica of the MSU-type family. This material was prepared with Pluronic P123 copolymer in mild acidity according to a two-step process. Its structure was explored by X-ray diffraction, N2 isotherms, SEM and TEM. The TEM study was completed by a 3D tomography analysis that allowed us to obtain information on the morphology of the pore-and-void system. The powder is homogeneous and made of nanoparticles (200 nm in size) built by the folding of ribbons with hexagonally-packed pores (pore diameter of 8.6 nm). This folding creates microvoids in the particles that give rise to an additional porosity. The properties of adsorption/separation of this new type of silica were tested for HPLC. Although the powder was not optimized for this application, the first results on ungrafted silica appear equivalent to those obtained with a commercial HPLC silica powder.@en