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cnrs I international w 24 | Focus magazine Contact information: Nicolas Giuseppone > giuseppone@ics.u-strasbg.fr Ludovic Jullien > ludovic.jullien@ens.fr Clément Sanchez > clement.sanchez@upmc.fr 08 dedicated to these so-called weak molecular interactions and the phenomenon of self-assembly, was pioneered 40 years ago by Nobel laureate Jean-Marie Lehn of the ISIS3 in Strasbourg. It has led to the encapsulation of medications, a bioinspired application that reproduces the self-assembly of organic cell membranes (see box, p. 27). TE CHNICAL COMPLEX ITY Yet mimicking nature is no mean feat— no surprise for a system whose complexity stems from billions of years of evolution. New combinations are constantly being tested, in a sort of natural game of Lego that was only recently observed in actual organic molecules. “In 2008 we showed that within a complex combination of molecules, some can recognize each other and self-replicate,” reports Nicolas Giuseppone, deputy director of the CNRS Institut Charles Sadron in Strasbourg. “This leads to the proliferation of the chemical species that reproduce themselves most efficiently, to the detriment of the others, which can be interpreted as a form of molecular Darwinism.” This is the subject of the emerging field called dynamic combinatorial chemistry, in which specific products are developed by mixing a set of molecules, before allowing the combinations to induce the natural selection of the most efficient substance. The technique is now being tested by the pharmaceutical industry for the development of medicines. A RE VOLUTION IN PRO GRE SS? The more they emulate nature, the closer chemists are to sparking a revolution by reproducing one of the fundamental characteristics of living beings: the functioning as an open system, which relies on a constant exchange of matter and energy with the surrounding environment. “Traditionally, chemists work with closed systems,” Jullien explains. “They mix substances in a beaker, then wait for the outcome. This results in a dead system that can evolve no further, whereas living matter never ceases to produce and consume molecules and energy. The idea of creating open systems that have the ability to evolve and adapt to environmental conditions, is an enticing goal.” And a distant one: for the moment, this field is still in its infancy, and its applications have yet to be devised. Nonetheless, by building upon the most essential of life’s characteristics, it could one day become the alpha and omega of bioinspiration. F. D. 01. Processus d’activation sélectif par transfert d’énergie uni-électronique ou radiatif (CNRS / ENS / UP MC). 02. Laboratoire chimie de la matière condensée de Paris (CNRS / UP MC / ENSCP / Collège de France). 03. Institut de science et d’ingénierie supramoléculaires (CNRS / Université de Strasbourg). The 100-nanometer fibers of this device (09), developed at the Institut Charles Sadron (10), are formed by the self-assembly of thousands of molecules and grow by self-replication. 08 This MIL-101 molecule was inspired by zeolites, minerals that have a porous skeleton structure. 09 10 © g. férey/CNRS Photothèque © c. frésill on/CNRS Photothèque © N. Giuseppone


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