What do they have in common a maze, Russian dolls and the ship inside a bottle? The three are objects with internal structure and the three have always fascinated humans. These objects are formed differently: the gardeners sow the walls of the maze, the concentric dolls are modeled separately and assembled later, and the ship enters the bottle with a little string stretches and raises its sails. What never happens is that the sculptor or a gardener enters the initial structure, to model it by carving the final shape from the inside.
This, not observed at the macroscopic scale, occurs spontaneously at the nanoscale if the ingredients are mixed properly. Nanotechnology allows a solid and compact structure, via chemical processes designed to attack, penetrate and advance digging the initial structure and creating geometric interconnected multi-cavity hollow structures ranging from molecular labyrinths to gold fullerenes, controlled by reaction fronts at the atomic level.
These capsules protect and carry molecules. If additionally capsules are nanoscaled and inorganic, thanks to its high density of electronic states, they respond to light in resonance and therefore may be open or closed, heated, manipulated by electromagnetic fields such as a cocktail of drugs transported safely to the therapeutic target and drugs administered sequentially on top of pharmacology where the dose is controlled at the cellular level. Last but not least, the synthesis of these structures is performed by controlling processes considered previously undesirable: corrosion! So the recovery of old problems, applied to the nanoscale, results in new exquisite nanostructures.
If being able to look, touch and manipulate matter at the nanoscale is already amazing, more amazing is that we are able to work inside the nanoparticle. The surface and interior of the nanostructures can be programmed in composition and architecture to make them like a tiny new research laboratory for chemical phenomena, optical, electrical, magnetic, thermal and mechanical stress. For example, it is possible to study quantum confinement phenomena or the coupling of internal and external walls excitations in the presence of electromagnetic radiation, or the study of internal catalytic reactions.
This work has been developed by Dr. Edgar Gonzalez and Prof. Víctor Puntes at the Catalan Institute of Nanotechnology (ICN), in collaboration with Prof. Jordi Arbiol at the Materials Science Institute of Barcelona (ICMAB-CSIC). And this breakthrough opens a new route for med