PEGylated Silk Nanoparticles for Anticancer Drug Delivery

Abstract

Silk has a robust clinical track\nrecord and is emerging as a promising\nbiopolymer for drug delivery, including its use as nanomedicine. However,\nsilk-based nanomedicines still require further refinements for full\nexploitation of their potential; the application of “stealth”\ndesign principals is especially necessary to support their evolution.\nThe aim of this study was to develop and examine the potential of\nPEGylated silk nanoparticles as an anticancer drug delivery system.\nWe first generated B. mori derived\nsilk nanoparticles by driving β-sheet assembly (size 104 ±\n1.7 nm, zeta potential −56 ± 5.6 mV) using nanoprecipitation.\nWe then surface grafted polyethylene glycol (PEG) to the fabricated\nsilk nanoparticles and verified the aqueous stability and morphology\nof the resulting PEGylated silk nanoparticles. We assessed the drug\nloading and release behavior of these nanoparticles using clinically\nestablished and emerging anticancer drugs. Overall, PEGylated silk\nnanoparticles showed high encapsulation efficiency (>93%) and a\npH-dependent\nrelease over 14 days. Finally, we demonstrated significant cytotoxicity\nof drug loaded silk nanoparticles applied as single and combination\nnanomedicines to human breast cancer cells. In conclusion, these results,\ntaken together with prior silk nanoparticle data, support a viable\nfuture for silk-based nanomedicines.