Silk fibroin-derived nanoparticles for biomedical applications.

The treatment of disease in the future will be influenced by the ability to produce therapeutic formulations that have high availability at the disease site, sustained and long-term release, with minimal to no toxicity to healthy tissues. Biologically derived delivery systems offer promise in this regard owing to minimization of adverse effects while increasing the efficacy of the entrapped therapeutic. Silk fibroin nanoparticles overcome barriers set by synthetic nondegradable nanoparticles made of silicone, polyethylene glycol and degradable polylactic acid-polyglycolic acid polymers. Silk fibroin-mediated delivery has demonstrated high efficacy in breast cancer cells. While the targeting is associated with the specificity of entrapped therapeutic for the diseased cells, silk fibroin-derived particles enhance intracellular uptake and retention resulting in downmodulation of more than one pathway due to longer availability of the therapeutic. The mechanism of targeting for the nanoparticle is based on the silk fibroin composition, beta-sheet structure and self-assembly into beta-barrels.