In organic molecules, functional groups are atom or atoms which are responsible for the characteristic properties of that molecule with the exceptions of double and triple bonds which are also functional groups.

Dumbbell-like bifunctional Au-Fe3O4 nanoparticles.
Adsorption of bifunctional organic disulfides on gold surfaces
Adsorption of bifunctional organic disulfides on gold surfaces - Journal of the American Chemical Society (ACS Publications)
Bifunctional Thymidylate Synthase-dihydrofolate Reductase from Leishmania tropica: Sequence Homology with the Corresponding Monofunc...
Facile One-Pot Synthesis of Bifunctional Heterodimers of Nanoparticles:? A Conjugate of Quantum Dot and Magnetic Nanoparticles
Asymmetric transfer hydrogenation of ketones with bifunctional transition metal-based molecular catalysts.
Enantioselective Michael reaction of malonates to nitroolefins catalyzed by bifunctional organocatalysts
Transforming growth factor beta is a bifunctional regulator of replication and collagen synthesis in osteoblast-enriched cell cultur...
Highly Enantioselective Conjugate Addition of Nitromethane to Chalcones Using Bifunctional Cinchona Organocatalysts
Urea- and thiourea-substituted cinchona alkaloid derivatives as highly efficient bifunctional organocatalysts for the asymmetric add...