Tumor-targeted biodegradable multifunctional nanoparticles for cancer theranostics

Mesoporous silica nanoparticles (MSN) attract extensive attention in area of cancer diagnosis and therapy because of their controllable nanostructures, easy surface modification and stable synthesis methods. However, their biodegradability was still controversial. This work explored the degradation effect of a type of biodegradable MSN (bMSN) in different environments and simultaneously endowed it with imaging functions and high-efficiency targeting effect on cancer cell, thus forming a multifunctional biodegradable drug carrier (bMSNss- GABA) for cancer theranostics. The bovine serum albumin-based Gd/Au complex (BSA-Gd/Au) was wrapped on the surface of bMSN through disulfide linkage, acting as contrast agent for magnetic resonance (MR) and fluorescence imaging, and then folate (FA), whose receptor (FR) is overexpressed in KB human oral epidermoid carcinoma cells, was modified on the nanocarriers as a targeting ligand. TEM revealed the degradation process of bMSN and a series of characterization methods verified the successful construction of bMSN-ss-GABA. Doxorubicin hydrochloride (DOX) loaded bMSN-ss-GABA (DOX@ bMSN-ss-GABA) was proved with redox-responsiveness, thereby triggering rapid drug release under specific tumor microenvironment of high glutathione concentration. Further, the excellent imaging capability was also fully inspected. What's more, the results of endocytosis and tumor growth inhibition of DOX@bMSN-ss-GABA demonstrated the highly effective targeting effect of hybird nanocarriers. Therefore, the prepared DOX@bMSN-ss-GABA might be used as a promising nanotheranostic agent for KB human oral epidermoid carcinoma.