Trade.Information

Topic Name: Discovery opens the way with the development of new nanostructurés materials

Category: Nanocharacterization

Research persons: Franck Artzner,Erik Dujardin

Location: rue de Navacelles,34090 Montpellier ,CNRS, France

Details

The study of a therapeutic peptide, Lanreotide (1), by researchers of the CNRS and University of Rennes made it possible to discover that this peptide had the capacity to be used as scaffolding with the spontaneous formation of silica nanotubes by simple mixture with a silica precursor (2) in water. This discovery opens the way with the development of new nanostructurés materials.The skeletons of vertebrate undoubtedly constitute the example more seizing effectiveness of the living organisms to form robust structures mixing organic and mineral matter closely, in fact of calcium phosphate. However, in the underwater world, of many organizations, often unicellular, make a success of a similar prowess by using silica (3) to manufacture carapaces and spines in order to protect itself or of the spicules, fibres which as well as collect the light towards their neurons the best optical fibres. Of architecture and form complexes, these natural structures are all the more astonishing as they are manufactured spontaneously in water under soft conditions of temperature and pressure following of the mechanisms still largely unknown. This turn of force thus makes dream the chemists who are often obliged to heat, draw or compress materials under aggressive conditions to format them.

Within the framework of their studies on the physicochemistry of a therapeutic peptide, the lanreotide, researchers of CNRS and University of Rennes discovered that this peptide could be used as scaffolding with the spontaneous formation of silica nanotubes by simple mixture with a silica precursor in water. These hybrid tubes are made of a perfect helicoid fitting of molecules of the drug in a tube of 24 Nm diameter covered inside and two fine and uniform walls with 2 silica Nm. The tubes are long several micrometers and are aligned out of fibres of a few millimetres. Their organization is thus hierarchically controlled on more than 6 orders of magnitude, that is to say the same report/ratio length as the diameter of a hair and the height of the Eiffel tower.

To complete this work of goldsmith, the made up team of researchers physicists, biologists and chemists, developed a slow technique allowing to coat with silica of the nanotubes of biological molecules which are formed in water. They had the surprise to observe that the silica deposit supports the progressive extension of the organic nanotube whose renewed end can then be used again as scaffolding following the silica deposit. This recurring process ensures at the same time the control of the organization on a molecular scale while manufacturing the organic scaffolding as the mineral settles. This process resembles surprisingly the construction of a skyscraper during which the assembly of the metal reinforcement and the concrete deposit are alternated with precision, except that it does not have there a workman and who the silica nanotubes are infinitely smaller…

This work opens two new prospects. On the one hand, they make it possible to better include/understand starting from a system simplified some astute, but still mysterious mechanisms, developed by nature, to manufacture skeletons, and spicules. In addition, they open the way towards new materials with nanometric dimensions whose organization in space is controlled until macroscopic sizes, thus conferring single properties to them. In the case of the silica nanotubes, the researchers have good hope to show that they lead the light as effectively as the natural spicules of sponges of sea…

The continuation of work relating at the same time on a better comprehension of the mechanisms of formation of natural mineral architectures of living organisms and to the synthesis of increasingly refined models, should allow others discovered on the means of designing and of carrying out materials increasingly more sophisticated and “intelligent” for biological or technological applications

About Researchers :

Franck Artzner
T 02 23 23 58 22
franck.artzner@univ-rennes1.fr

Erik Dujardin
T 05 62 25 78 38
dujardin@cemes.fr

References:
Hierarchical architectures by synergy between dynamical template coil-assembly and biomineralization, E. Pouget (1), E. Dujardin (2), A. Cavalier (3), A. Moreac (1), C. Valéry (4), V. Marchi-Artzner (5), T. Weiss (6), A. Renault (1), Mr. Paternostre (7), F. Artzner (1), Natural Materials June 2007

(1) Group Condensed Matière and Materials (CNRS, Université Rennes 1)
(2) CEMES, Center of Development de Matériaux and Structural Studies (CNRS, Toulouse)
(3) Cellular and Molecular interactions (CNRS, University Rennes 1)
(4) IPSEN (Barcelona, Spain)
(5) Chemical sciences of Rennes (CNRS, University Rennes 1)
(6) European Synchrotron Radiation Facility (Grenoble)
(7) IBiTechS (ECA Saclay, CNRS)

Notes:
1) Lanreotide is developed by group IPSEN

2) Silica molecules in solution

3) Silica is the constituent majority one of the earth's crust and commonly used in the form of glass

In The Images:

Hierarchical organization of the nanotubes of glasses seen in electronic microscopy (high, bars: 100nm) in polarized light (low, 1mm bars)