摘要:
Nanofibers and microfibers having a core and a polymer shell surrounding the core are provided. The shell includes a plurality of channels that extend from an outer shell surface to the core, and one or more agents, such as pharmacological materials, proteins, viruses, plasmid DNA, bacterial cells, drug-loaded nanoparticles, are encapsulated within the core. The one or more agents discharge from the core through the channels at a controlled rate. The channels are formed by porogen material within the polymer shell.