In collaboraton with Prof. Brad Pentelute’s lab, we are applying Pd-mediated cross coupling reactions for the functionaliztion of biomolecules. We have found that oranometallic palladium complexes can be used as bench-stable, practical reagents for highly chemoselective arylation of biomolecules of varying complexity under biocompatible reaction conditions. The resulting products possess increased stability against acids, bases, and thiol nucleophiles compared to the commonly used succinimide and acetamide bioconjugates. Furthermore, the stability of the arylated peptides towards oxidation can be easily tuned by varying the substitution pattern at the aromatic ring. The utility of the new palladium-mediated bioconjugation reaction is further highlighted by the synthesis of novel classes of biotherapeutics.