  Patchy particles have received great attention due to their ability to
develop directional and selective interactions and serve as building units for
the self-assembly of innovative colloidal molecules and crystalline structures.
Although synthesizing particles with multiple dissimilar patches is still
highly challenging and lacks efficient methods, these building blocks would
open paths towards a broader range of ordered materials with inherent
properties. Herein, we describe a new approach to pattern functional DNA
patches at the surface of particles, by the use of colloidal stamps. DNA inks
are transferred only at the contact zones between the target particles and the
stamps thanks to selective strand-displacement reactions. The produced
DNA-patchy particles are ideal candidates to act as advanced precision/designer
building blocks to self-assemble the next generation of colloidal materials.
