cRGD-modified core–shell mesoporous silica@BSA nanoparticles for drug delivery

Nano core–shell drug carriers with high stability, low toxicity, and targeted drug delivery are significance for the delivery of anti-tumor drugs. In this study, Albumin from bovine serum (BSA), serving as a capping agent, was conjugated to MSNs via a cleavable disulfide bond to generate a redox-responsive nanocarrier (MSNs@BSA). Subsequently, cRGD peptide, as a targeting ligand, was modified on the particle surface by a protein cross-linker to obtain nanoparticles with tumor cell-targeting properties (RGD-MSNs@BSA). The construction of RGD-MSNs@BSA was confirmed by DLS analysis, scanning electron microscope (SEM), transmission electron microscopy (TEM), electron dispersive spectroscopy (EDS), X-Ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR), respectively. It was displayed that the model anticancer drug doxorubicin (DOX) was efficiently and stably encapsulated in RGD-MSNs@BSA in the absence of glutathione (GSH), and an outbreak of DOX was observed when the particles were exposed to a GSH-containing environment. It demonstrated that disulfide-linked BSA capping can increase the drug loading stability, while enduing it redox sensitivity. Flow cytometry and fluorescence microscope tests displayed that cellular uptake of RGD-MSNs@BSA was much higher than that of particles without cRGD and free DOX. These results indicated that RGD-MSNs@BSA can increase drug tumor-targeting and drug cellular uptake.