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A facile one-step solvothermal method was developed for the homogeneously confined growth of ultra-small (∼1.5 nm) and monodispersed 2H phase MoS2 nanodots into mesoporous silica nanoparticles (MSNs).

Bimetallic nanocatalysts often display enhanced physical and chemical properties compared to those of their monometallic counterparts. Herein, we introduce a simple method to fabricate an island like array of tiny Ag nanoparticles bounded on triangular Au nanoplates as the surface-enhanced Raman scattering (SERS) substrate. The surface morphology of the synthesized nanoparticles was characterized via field emission scanning electron microscopy (FE-SEM), and atomic force microscopy (AFM). Rhodamine 6G (R6G) is used as a model analyte to evaluate the performance of the tiny Ag nanoparticle bounded triangular Au nanoplates as a SERS-active substrate and validate the SERS effect. The fabricated SERS substrate showed drastically enhanced intensity with a SERS enhancement factor as high as 107, which is enough to detect a single molecule, and excellent reproducibility (less than ±5%) of the signal intensity. This is because of the island-like tiny Ag nanoparticle bounded triangular Au nanoplates and their large number of “hot spots”. This substrate could also be used for label-free immunoassays, biosensing, and nanoscale optical antennas and light sources.

Receptor-mediated delivery of hydrophobic antitumor drugs is of great interest in chemotherapy of tumors such as glioma. Specific expression of interleukin-13 (IL-13) receptor has been characterized in glioma. In this work, a specific peptide corresponding to the residues within IL-13 protein, designated as IP, was exploited, for the first time, as a glioma-targeting ligand. IP was conjugated to mesoporous silica nanoparticles (MSN) via bifunctional polyethyleneglycol (PEG), constructing the vector MSN–PEG–IP. The successful synthesis of MSN–PEG–IP was demonstrated via Fourier transform infrared spectroscopy. The transmission electron microscopy result showed that the size of MSN–PEG–IP was about 160 nm with an average pore diameter of around 2.6 nm. The cellular uptake of doxorubicin (DOX)-loading IP-modified system (MSN–PEG–IP/DOX) was concentration-dependent in glioma U251 cells. IP modification could significantly enhance the cellular uptake of the drug delivery system in U251 cells but not in normal astrocyte 1800 cells, compared to unmodified counterparts. This effect was further verified by cytotoxicity analysis. Furthermore, the intracellular trafficking result indicated that the loaded DOX was mostly accumulated in nuclei, even at very short incubation time (5 min). All the results suggested that IP could be applied as a special glioma-targeting ligand, and MSN–PEG–IP is a potential vector for delivering hydrophobic chemotherapeutic drugs to IL-13 receptor-overexpressed tumors.