Chemistry: science and art of matter

Chemistry is a science whose goal is not only discovery, but also and above all creation. In this, it is an art of the complexification of matter. To grasp the logic of the latest developments in chemistry, we have to take a step back in time some four billion years.

Chemistry videos plays a central role in our daily life, both through its place in the natural sciences and knowledge, as well as through its economic importance and its omnipresence. By dint of being present everywhere, it is often forgotten, and it risks not being reported anywhere. It does not put on a spectacle but, without it, the achievements that we agree to find spectacular could not see the light of day: therapeutic exploits, spatial feats, marvels of technique, etc. It makes a decisive contribution to the needs of humanity in food and medicine, clothing and housing, energy and raw materials, transport and communications. It provides materials for physics and industry, models and substrates for biology and pharmacology,

A world without chemistry would be a world without synthetic materials, therefore without telephone, without computer, without cinema, without synthetic fabrics. It would also be a world without aspirin, soap, shampoo, toothpaste, cosmetics, contraceptive pills, without paper, therefore without newspapers or books, without glue, without paints.

Let us be careful not to forget that chemistry helps art historians to unravel some of the manufacturing secrets of paintings and sculptures that we admire in museums, that it allows forensic sleuths to analyze the samples taken at crime scenes and to trace the culprits more quickly, and that it reveals the molecular subtleties of the dishes that bewitch our taste buds.

Alongside physics which deciphers the laws of the Universe and biology which decodes the rules of living things, chemistry is the science of matter and its transformations. Life is its highest expression. It plays a primordial role in our understanding of material phenomena, in our capacity to act on them, to modify them, to control them.

For almost two centuries, molecular chemistry has built a vast collection of increasingly sophisticated molecules and materials. From the synthesis of urea in 1828 (which brought about a real revolution, by providing the proof that it was possible to obtain an "organic" molecule using an inorganic compound) to the completion, in the 1970s, of the synthesis of vitamin B12, this discipline has continued to assert its power on the structure and transformation of matter.

The molecule seen as a Trojan Horse Beyond molecular chemistry extends the immense field of so-called supramolecular chemistry, which is interested not in what happens in molecules, but in what is going on between them . Its goal is to understand and control the way molecules interact with each other, transform, cling, ignoring other partners. Emil Fischer [German Nobel Prize for Chemistry 1902] used the image of the key and the lock. Today we are talking about "molecular recognition".

It is in the biological field that the role of these molecular interactions is most striking: protein units assemble to form hemoglobin; white blood cells recognize and destroy foreign bodies; the AIDS virus finds its target to invest it; the genetic code is transmitted by writing and reading the alphabet of protein bases, etc.

Take the very telling example of the “self-organization” of the tobacco mosaic virus: no less than 2,130 simple proteins assemble to form a helical tower.

The efficiency and elegance of these natural phenomena are so fascinating for a chemist that he is tempted to reproduce them or to invent new processes allowing the creation of new molecular architectures with multiple applications. Why not imagine molecules capable of transporting a DNA fragment intended for gene therapy, for example, to the heart of a chosen target? These molecules would be "Trojan horses" which would make their passenger cross barriers deemed insurmountable, such as cell membranes.

A large number of researchers around the world are patiently building “tailor-made” supramolecular structures. They observe how the molecules, mixed without apparent order, find themselves again, recognize each other and then gradually assemble, to lead spontaneously but perfectly in control to the final supramolecular structure.

Thus, inspired by the phenomena that nature presents to us, the idea germinated to create and control the appearance of supramolecular assemblies, in other words to carry out “molecular programming”. The chemist designs basic building blocks (molecules endowed with certain structural and interactional properties), then sets up the “cement” (the assembly code) responsible for binding them. He thus obtains a superstructure by self-organization. The synthesis of molecular building blocks capable of self-organizing is much simpler than the synthesis of the final structure would be. This line of research opens up vast perspectives, particularly in the field of nanotechnologies: instead of manufacturing nanostructures, nanostructures are allowed to manufacture themselves by self-organization,

More recently still has emerged a so-called adaptive chemistry where the system, in order to build itself, selects itself among the available bricks, and becomes capable of adapting the constitution of its objects in response to the demands of the environment. This chemistry, which I call “dynamic constitutional chemistry”, thus displays a Darwinian coloring!

From Matter to Life In the beginning was the original explosion, the Big Bang, and physics reigned. Then came chemistry, at warmer temperatures. The particles formed atoms, which united to produce increasingly complex molecules which, in turn, joined together in aggregates and membranes, thus giving rise to the first cells from which life emerged on our planet, some 3.8 billion years ago.

From divided matter to condensed matter then organized, living and thinking, the deployment of the Universe feeds the evolution of matter towards an increase in complexity by self-organization under the pressure of information. The task of chemistry is to reveal the paths of self-organization and to trace the paths leading from inert matter, by a purely chemical probiotic evolution, to the break of life, and beyond to living matter then thinking. It thus provides the means to question the past, explore the present and build bridges to the future.

Through its object (the molecule and the material), chemistry expresses its creative power, its power to produce new molecules and materials - new because they did not exist before being created by recomposition of the arrangements of atoms in combinations and original and infinitely varied structures. By the plasticity of the forms and the functions of the chemical object, chemistry is not without analogy with art. Like the artist, the chemist imprints the products of his imagination on matter. The stone, the sounds and the words do not contain the work that the sculptor, the composer and the writer model of them. In the same way, the chemist creates original molecules, new materials and new properties from the elements that make up matter.

The essence of chemistry videos is not only to discover, but to invent and, above all, to create. The Book of Chemistry is not just for reading, it is for writing. The chemistry score is not just to play, but to compose.