ABSTRACT
Patchy particles are fabricated using a method of embedding-into and extracting-from thick, biocompatible, gel-like HA/PLL films. Control over the patchiness is achieved by adjusting the stiffness of films, which affects embedding and masking of particles. The stiffness is adjusted by the concentration of gold nanoparticles adsorbed onto the surface of the films.
Subject(s)
Gold/chemistry , Metal Nanoparticles/chemistry , Nanotechnology/methods , Hyaluronic Acid/chemistry , Polylysine/chemistry , Surface PropertiesABSTRACT
Spontaneous embedding of gold nanoparticle (NP) aggregates or polyelectrolyte microcapsules modified with NPs in biocompatible hyaluronic acid/poly(l-lysine) films is reported. The NPs were adsorbed in the aggregated state to induce near-IR light absorption. The films functionalized with gold NPs become active in response to a "biologically friendly" near-IR laser at a power of about 20 mW. The activation is characterized by a localized temperature increase in the film, allowing conversion of light energy to heat into confined volumes. Microcapsules adsorbed onto the film can release its cargo under stimulation with near-IR light because of localized permeability changes in their walls. This work is aimed at layer-by-layer film-based biomedical coatings and active surfaces with light-sensitive features wherein metal NPs and microcapsules are used as active centers or carriers with remote control of functionalities.