Abstract: The present invention relates to a method, comprising: coating a surface with a mussel adhesive protein such that a first layer comprising the MAP is achieved on the first surface, and providing a second layer comprising a first plurality of particles on at least a portion of said first layer comprising said MAP. It also relates to a device comprising a substrate having a first surface; a first layer comprising said MAP, said first layer being arranged on said first surface, and a second layer comprising a first plurality of particles attached to at least a portion of said MAP of said first layer. The present invention is based on the realization that a MAP can advantageously be used to immobilize particles on a substrate, for example in a layer-by-layer assembly. Thereby, providing a highly functionalized surface.