Biomolecules are provided having multiple binding sites for attachment to
a substrate surface. The multiple attachment sites may be produced
directly on the biomolecule or through use of branched phosphoramidite
moieties that can be added in multiple to form dendritic structures which
can in turn provide attachment sites for substrate binding moieties.
Substrate binding moieties may include noncovalent binding moieties. For
covalent binding moieties oligonucleotides containing hydrazides are
provided. These hydrazides can be introduced via protected building
blocks such as phosphoramidites or via building blocks containing
precursor forms of such hydrazides.