The synthesis of broccoli sprout extract-loaded silk fibroin nanoparticles as efficient drug delivery vehicles: development and characterization

Targeted drug delivery of biological molecules using the development of biocompatible, non-toxic, and biodegradable nanocarriers can be a promising method for cancer therapy. In this study, silk fibroin protein nanoparticles (SFPNPs) were synthesized as a targeted delivery system for sulforaphane-rich broccoli sprout extract (BSE). The BSE-loaded SFPNPs were conjugated with polyethylene glycol and folic acid, then their physicochemical properties were characterized via UV-Vis, XRD, FTIR, DLS, FE-SEM, and EDX analyses. In vitro release profile, antioxidant and anticancer activities of NPs were also studied. The FE-SEM and DLS analyses indicated stable NPs with an average size of 88.5 nm and high zeta potential (-32 mV). The sulforaphane release profile from NPs was pH-dependent, with the maximum release value (70%) observed in simulated intestinal fluid (pH = 7.4). Encapsulation of BSE also decreased the release rate of sulforaphane from the capsules compared to the free BSE. In vitro cytotoxicity of BSE and NPs on breast cancer cell lines (MCF-7) were concentration-dependent, and IC50 for BSE and NPs were acquired in 54 and 210 μg mL−1, respectively. Moreover, the NPs demonstrated no appreciable cytotoxicity in normal mouse fibroblast (L929) cell lines. These results indicated that biocompatible NPs synthesized as controlled and long-term targeted drug delivery systems can be a potential candidate for breast cancer therapy.