Presentation of therapeutic proteins on material surfaces is challenged by random immobilization chemistries through lysine or cysteine residues, typically leading to heterogeneous product outcome. Pharmaceutical quality standards warrant a controlled process ideally through site specific conjugation. Therefore, we deployed genetic codon expansion to engineer a propargyl-l-lysine (Plk)-modified FGF-2 analogue, enabling site-specific copper(I)-catalyzed azide alkyne cycloaddition (CuAAC). Site-specific decoration of Plk-FGF-2 to particles sparked cell proliferation of human osteosarcoma cells in a spatially controlled manner around the decorated carrier, rendering this approach instrumental for the future design of quality-improved bioinstructive scaffold outcome.