N-Azidoacetylmannosamine is an azide-labeled sugar that can be metabolically incorporated into glycoproteins. N-Azidoacetylmannosamine can then react with alkynes or phosphines that are linked to fluorescent or biotin tags for visualization or capture of the glycoproteins. N-Azidoacetylmannosamine can be used for studying glycan structures and functions in vivo[1].