Science Buddies: "Ask an Expert"

When I clip my nails, the new nail edges are sharp and lightly-colored, but within an hour or two the edges become rounded and darker. Does oxydation play a role in this process?

Thank you for your time.

Phillip Moss

Hi Phillip,

I am a researcher in biochemistry and molecular biology and, although I have never read anything about fingernails responding to oxygen, it is an intriguing question. My initial feeling would be that oxidation is not involved, that the nail becomes smoothed by simple abrasion. Maybe also there is a physical process going on where the nail's keratin fibers draw together after cutting and that results in a rounding and smoothing of the cut surface.

You could try cutting a fingernail and then putting a bandaid over it to prevent abrasion and see if the nail becomes smooth. If you have close-up lenses for your phone camera you could take before and after pix over a period of hours or days to document the changes. You may discover something that nobody else has noticed--simply because they never looked!

Stay curious,

Sybee