Detailed Structure of Diamond-Type Lipid Cubic Nanoparticles

• Published in: Journal of the American Chemical Society Vol. 128; no. 17; pp. 5813 - 5817
• Main Authors: Angelov, Borislav, Angelova, Angelina, Papahadjopoulos-Sternberg, Brigitte, Lesieur, Sylviane, Sadoc, Jean-François, Ollivon, Michel, Couvreur, Patrick
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 03.05.2006
• Subjects: Biological and medical sciences; Disperse state. Micelles; Fundamental and applied biological sciences. Psychology; Lipids - chemistry; Molecular biophysics; Molecular Structure; Nanoparticles; Physico-chemical properties of biomolecules; Glycerol(tri-O-oleoyl); Immunoglobulins; Supramolecular structure; Nanostructure; Particle suspension; Electron microscopy; Cryogenic temperature; Colloid particle; Submicron particle; Surface structure
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja060082c

Supramolecular three-dimensional self-assembly of nonlamellar lipids with fragments of the protein immunoglobulin results in a bicontinuous cubic phase fragmented into nanoparticles with open water channels (cubosomes). The structure of the diamond-type cubic nanoparticles is characterized experimentally by freeze−fracture electron microscopy, and it is mathematically modeled with nodal surfaces emphasizing the fluid-like undulations of the cubosomic interfaces. Based on scaling-up and scaling-down approaches, we present stable and intermediate-kind nanoparticles resulting from the cubosomic growth. Our results reveal the smallest stable diamond-type cubosomic entity that can serve as a building block of more complex nanostructured fluid drug delivery vehicles of therapeutic proteins. The evidence presented for lipid-bilayer undulations in the surface region of the protein/lipid cubosomes could have important consequences for possible applications of these hierarchically organized porous nanoparticles.