Biocompatible protein nanocontainers for controlled drugs release.

We designed a biocompatible carrier for controlled release of hydrophobic drugs. The designed carrier was prepared by sonicating oil in a protein aqueous solution forming a protein nanocontainer composed of an inner gel core and an outer protein shell. Two model drugs were loaded into the designed nanocontainers by dissolving drugs in the oil phase before sonication. The loading capacity was up to 0.9 mg/mL for the amphiphilic drug rifampicin, while it reached to 19 mg/mL for the hydrophobic drug indomethacin. The encapsulated drugs were released at different temperatures. At 37 degrees C, only less than 20% of the drug was released due to the protection by the gel core. Increasing temperature to 40 degrees C led to a completely release of the remaining drug. The drug release showed drastic temperature dependence. The biocompatibility of the protein nanocontainers was evaluated by incubating the nanocontainers in the 3T3 cell and B-LCL cell lines. Both experiments indicated an excellent biocompatibility of the designed nanocontainers.