Exploring Hollow Mesoporous Silica Nanoparticles as a Nanocarrier in the Delivery of Foot-And-Mouth Disease Virus-like Particle Vaccines

Virus-like particle (VLP) vaccine is considered to be the most promising candidate alternative to the traditional inactivated vaccine for foot-and-mouth disease (FMD). To elicit a desired immune response, hollow mesoporous silica nanoparticles (HMSNs) have been synthesized and utilized as a nanocarrier for FMD VLP vaccine delivery. The as-prepared HMSNs displayed a relatively small particle size (∼260 nm), large cavity (∼150 nm), and thin wall (∼55 nm). The inherent structural superiorities make them ideal nanocarriers for the FMD VLP vaccine, which exhibited good biocompatibility, great protein-loading capacity, high antibody-response level, and protective efficiency, even comparable to commercial adjuvant ISA 206. All the results suggested that HMSNs may be a valid nanocarrier in VLP-based vaccines.

Controlled-release of apatinib for targeted inhibition of osteosarcoma by supramolecular nanovalve-modified mesoporous silica

Targeted delivery of antitumor drugs has been recognized as a promising therapeutic modality to improve treatment efficacy, reduce the toxic side effects and inhibit tumor recurrence. In this study, based on the high biocompatibility, large specific surface area, and easy surface modification of small-sized hollow mesoporous silica nanoparticles β-cyclodextrin (β-CD)-benzimidazole (BM) supramolecular nanovalve, together with bone-targeted alendronate sodium (ALN) were constructed on the surface of small-sized HMSNs. The drug loading capacity and efficiency of apatinib (Apa) in HMSNs/BM-Apa-CD-PEG-ALN (HACA) were 65% and 25%, respectively. More importantly, HACA nanoparticles can release the antitumor drug Apa efficiently compared with non-targeted HMSNs nanoparticles in the acidic microenvironment of the tumor. In vitro studies showed that HACA nanoparticles exhibited the most potent cytotoxicity in osteosarcoma cells (143B cells) and significantly reduced cell proliferation, migration and invasion. Therefore, the drug-efficient release of antitumor effect of HACA nanoparticles is a promising way to treat osteosarcoma.

Cargo-influences on the biodistribution of hollow mesoporous silica nanoparticles as studied by quantitative 19F-magnetic resonance imaging

HYPOTHESIS

Biodistribution is a key issue when it comes to medical applications of nanomaterials. Hollow mesoporous silica nanoparticles (HMSNs) loaded with fluorine compounds can be applied as positive magnetic resonance imaging (MRI) contrast agents (CAs). These CAs exhibit an unusual biodistribution which is influenced by the cargo and which could be linked to their serum protein adsorption behaviour.

EXPERIMENTS

HMSNs were post-synthetically loaded with perfluoro-15-crown-5-ether (PFCE). The ¹⁹F signal was quantified with MRI in a murine model. Furthermore protein adsorption tests were performed in full serum.

FINDINGS

Quantitative analysis of the ¹⁹F-signal revealed that the particles were exclusively accumulating in the liver 24h post-injection, and no accumulation in other reticuloendothelial system (RES) organs like spleen or lung was observed. The protein corona around non-loaded and loaded particles was therefore analysed, and more proteins adsorbed on PFCE-loaded particles as compared to the bare particles, and importantly, the amount of apolipoproteins A-1 and A-2, was clearly elevated for the PFCE-loaded particles. The results underline that the type of cargo may have major influences on the biodistribution of mesoporous silica drug vectors.

Surfaces with Sustainable Superhydrophobicity upon Mechanical Abrasion

Surfaces with sustainable superhydrophobicity have drawn much attention in recent years for improved durability in practical applications. In this study, hollow mesoporous silica nanoparticles (HMSNs) were prepared and used as reservoirs to load dodecyltrimethoxysilane (DDTMS). Then superhydrophobic surfaces were fabricated by spray coating HMSNs with DDTMS as particle stacking structure and polydimethylsiloxane (PDMS) as hydrophobic interconnection. The mechanical durability of the obtained superhydrophobic surface was evaluated by a cyclic sand abrasion. It was found that once the surface was mechanically damaged, new roughening structures made of the cavity of the HMSNs would expose and maintain suitable hierarchical roughness surrounded by PDMS and DDTMS, favoring sustainable superhydrphobicity of the coating. The surfaces could sustain superhydrophobicity even after 1000 cycles of sand abrasion. This facile strategy may pave the way to the development of robust superhydrophobic surfaces in practical applications.