Reactive lignin nanocapsules
catalyze a pigmentation reaction to
furnish an innovative type of sustainable polyvalent bioink. In this
nanodevice, the pigment, vehicle, binder, and additive are included
in a single confined spherical space. Bioinks with different shades
of color, black, gray, yellow-like, pink-like, and red/brown hues,
have been prepared by selecting the reactants and the pigmentation
process. Lignin nanocapsules play multiple functions in the support
and activation of the enzyme necessary for the synthesis of pigments.
Lignin nanocapsules protected the melanin pigment from alkaline and
UV-degradation treatment.