| 초록 |
Polystyrene hollow particles with controllable holes in their surfaces were prepared by swelling solid beads with a good solvent, followed by freeze-drying with liquid nitrogen. The void size of such a hollow particle was controlled by the solubility parameter of the solvent while the hole diameter was determined by the flux of solvent evaporation. This novel class of hollow particles could serve as mesoscale capsules to encapsulate various types of materials that include organic dyes, fluorescent proteins, superparamagnetic iron oxide nanoparticles, and spherical polymer beads. As a major advantage of this new system, the functional material to be encapsulated could be directly loaded through the holes, which could be closed by heating the sample above the glass transition temperature of polystyrene. |
