According to scientists at the University of Southampton, they have identified a number of key characteristics that can enhance the penetration of nanoparticles through skin. In their research, they were able to demonstrate that gold nanoparticles could be made to penetrate deeper by changing the shape and surface charge. It turns out positively charged, nanorod shaped particles penetrated skin into the dermis.
Cosmetic chemist implications
For cosmetic chemists I see two applications of this research.
1. A method of creating nanoparticle delivery systems for cosmeceutical type ingredients.
2. A method for creating nanoparticles of sunscreen that will not penetrate the skin. They’ve demonstrated the factors that affect penetration so we could (theoretically) control the shape to inhibit penetration.
Nanoparticles could indeed be the way of the future for cosmetic formulating. However, there could be some significant marketing hurdles if the technology becomes something of which people are afraid. Right now public opinion shows a 3 to 1 ratio of people who see benefits versus people who see negative risks. It remains to be seen where the large minority (44%) of people who are unsure about the risks of nanotechnology end up. If groups like the EWG are able to shape public opinion, it’s not promising.