Fully biobased nanoparticles harnessed from the lignification of wood are introduced in this paper. A phenolic oligomer is produced by the horseradish peroxidase-catalyzed polymerization of ferulic acid, which is a lignin precursor. The oligomer spontaneously forms monodispersed nanoparticles (79.7 +/- 18.4 nm) via self-assembly in the reaction solution.