| abstract |
Hollow particles wherein the permeability of the particle changes in respons e to a change in one or more environ-mental conditions, such as pH, temperature, light, ionic strength, electric field, magnetic field, solvent composition, etc. The hollow particles are preferably in the nanometer to micrometer size range. Methods of making and using the responsive hollow particles. In one embodiment, the shell of the hollow particles is formed from a stimul us responsive polymer. The particles allow for the encapsulation of therapeutic, prophylactic, and diagnostic agents, as well a s other materials such as cosmetics, dyes or pigments, fragrances, and other compounds with industrial significance. The surface optionally can be modified with specific ligands that allow the particles to be directed to a specific target via molecular recognition. |