The Chemistry of Cosmetics

Cosmetics are an excellent example of how discoveries in chemistry are part of our day-to-day lives. In fact, just reading the composition of any common cosmetic can become a chemistry class: water, emulsifiers, preservatives, thickeners, pH stabilizers, dyes and fragrances, combined in different ratios, for different purposes.

The use of cosmetics – that is, chemical compounds to improve our appearance – is not a recent phenomenon. It is said that the Egyptian queen Cleopatra bathed in milk, as a way to keep her skin beautiful and soft. Which probably actually worked  because it is proven that lactic acid – one of  milk’s  chemical compound – acts on the deeper layers of the epidermis, promoting the removal of dead cells and skin renewal.

In ancient Greece, three thousand years before Christ, women  used powdered lead carbonate to make their faces paler. Unfortunately, we now know that lead carbonate is toxic and it is possible that the pursuit of beauty cost the lives of some of these women.

In many cases, these different cosmetic products have a strong component of scientific innovation, developed in modern research laboratories. Suffice to say that the cosmetics industry was among the first to adapt the new features of nanotechnology through the use of nanoparticles to improve the quality of their products and satisfy the desires of its customers.

Nanoparticles are particles of intermediate size on the scale between atoms and macroscopic materials. Something like a thousand times greater than the diameter of an atom or thousands of times smaller than the thickness of a hair.

This gives them the unique properties, which can be modulated by changing its size.

Typical examples of the application of nanotechnology in cosmetics are dioxide titanium nanoparticles in sunscreens (that give complete protection without the effect of a white layer on the skin), the use of solid lipid nanoparticles for slow release of fragrance in perfumes, or creating nanovesicles as carriers to provide a better penetration of the active ingredients on the skin.

And if I’ve managed to awaken in you the interest for the chemistry of beauty, now you can continue to enjoy the beauty of the chemistry of things …