What is biotine?

Answer 1

Did you mean "biotin"?

"Biotin is a water-soluble B-complex vitamin which is composed of an ureido (tetrahydroimidizalone) ring fused with a tetrahydrothiophene ring"

Definition from Wikipedia.

http://en.wikipedia.org/wiki/Biotin

It is commonly used to promote hair, skin, and nail growth.

Answer 2

Biotin is an essential vitamin that has been grouped with the B-complex vitamins since it was discovered, in yeast alongside other B vitamins.
Although it is technically known as vitamin B7, it is usually simply referred to as biotin. It is currently being marketed for improving nail, skin, and hair aesthetics. There is not much evidence to support biotin's role in this. Biotin's general role is an enzymatic cofactor.