Surface PEGylation of mesoporous silica materials via surface-initiated chain transfer free radical polymerization: Characterization and controlled drug release

Smart Mesoporous Silica Nanoparticles for Protein Delivery

Mesoporous silica nanoparticles (MSN) have attracted a lot of attention during the past decade which is attributable to their versatile and high loading capacity, easy surface functionalization, excellent biocompatibility, and great physicochemical and thermal stability. In this review, we discuss the factors affecting the loading of protein into MSN and general strategies for targeted delivery and controlled release of proteins with MSN. Additionally, we also give an outlook for the remaining challenges in the clinical translation of protein-loaded MSNs.

One-pot ultrafast preparation of silica quantum dots and their utilization for fabrication of luminescent mesoporous silica nanoparticles

Silica quantum dots (SiQDs) and their luminescent composites have displayed great potential for biomedical applications owing to their chemical inert and low cost. In this work, we report a facile, cost-effective and ultrafast strategy to prepare a stable luminescent SiQDs using N-[3-(trimethoxysilyl)propyl]ethylenediamine (EDAS) and salicylaldehyde as precursors for the first time. These luminescent SiQDs were further utilized for fabrication of luminescent mesoporous silica nanoparticles (MSNs) through direct encapsulation of SiQDs by MSNs. The novel synthetic and modified SiQDs uses commercial raw materials and the entire reaction can be completed within 30 s. The successful preparation of SiQDs and SiQDs@MSNs were characterized by various characterization equipments. The cell viability as well as cell uptake behavior of SiQDs@MSNs were also examined to evaluate their potential for biomedical applications. We demonstrated that these SiQDs@MSNs are low toxicity and of great potential for biological imaging. Based on the above results, we believe that these SiQDs@MSNs should be novel and promising candidates for biomedical applications owing to their intense fluorescence, biocompatibility and high specific surface areas.

Theranostic micelles based on upconversion nanoparticles for dual-modality imaging and photodynamic therapy in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is frequently metastatic once diagnosed and less likely to respond to curative surgery, emphasizing the need for the development of more sensitive and effective diagnostic and therapeutic strategies. Epithelial cell adhesion molecule (EpCAM) is deemed as the biomarker of cancer stem cells (CSCs), which are mainly responsible for the recurrence, metastasis and prognosis of HCC. In this study, we discuss the use of mitoxantrone (MX), an antitumor drug and a photosensitizer, for designing upconversion nanoparticle-based micelles grafted with the anti-EpCAM antibody, for dual-modality magnetic resonance/upconversion luminescence (MR/UCL)-guided synergetic chemotherapy and photodynamic therapy (PDT). The obtained micelles exhibit good biocompatibility, high specificity to HCC cells and superior fluorescent/magnetic properties in vitro. In vivo results demonstrate that the targeted micelles exhibited much better MR/UCL imaging qualities compared to the nontargeted micelles after the intravenous injection. More importantly, PEGylated UCNP micelles loaded with MX and grafted with anti-EpCAM antibody, denoted as anti-EpCAM-UPGs-MX, showcased the most effective synergetic antitumor efficacy compared with other treatment groups both in vitro and vivo. The remarkable antitumor effect, coupled with superior simultaneous dual-modality MR/UCL imaging as well as good biocompatibility and negligible toxicity, makes the UPG micelles promising for future translational research in HCC diagnosis and therapy.