An unsought and expensive way to make gold nanoparticles on the way to the development of SiO2@ZrO2 nanocarriers for cancer vaccination

SiO2/hyaluronic acid nanoparticles carry CaO2, DOX and p53 plasmid to effectively achieve ion interference/chemical/gene multimodal therapy of lung cancer

Monotherapy of lung cancer shows limited therapeutic effects due to its poorly targeted enrichment and low bioavailability. Using nanomaterials as carriers to form drug delivery systems has become a popular method to improve the targeting of anticancer drug therapy and patients' safety. However, the uniformity of the loaded drugs and the unsatisfactory effects are still the bottleneck in this field up to now. This study aims to construct a novel nanocomposite carrying 3 different types of anticancer drugs to enhance treatment efficacy. Herein, mesoporous silica (MSN) with high loading rate was constructed by dilute sulfuric acid thermal etching as the framework. Hyaluronic acid (HA) was loaded with CaO₂, p53 and DOX to construct nanoparticle complexes-SiO₂@CaO₂@DOX@P53-HA. First, MSN was proved to be a porous sorbent with a mesoporous structure through BET analysis. The images obtained from the uptake experiment clearly show the gradual enrichment of the DOX and Ca²⁺ within the target cell. For in vitro experiments, the pro-apoptotic effects of SiO₂@CaO₂@DOX@P53-HA significantly increased compared to that of the single-agent group at different time points. Furthermore, in the tumor-bearing mouse experiment, the tumor volume was remarkably inhibited in the SiO₂@CaO₂@DOX@P53-HA group compared to that in the single-agent group. By observing the pathological sections of the euthanized mice, it is obvious that the tissues of the mice treated with the nanoparticles were more intact. Based on these beneficial results, it is believed that multimodal therapy is a meaningful treatment strategy for lung cancer.

Silica@zirconia Core@shell Nanoparticles for Nucleic Acid Building Block Sorption

The development of delivery systems for the immobilization of nucleic acid cargo molecules is of prime importance due to the need for safe administration of DNA or RNA type of antigens and adjuvants in vaccines. Nanoparticles (NP) in the size range of 20-200 nm have attractive properties as vaccine carriers because they achieve passive targeting of immune cells and can enhance the immune response of a weakly immunogenic antigen via their size. We prepared high capacity 50 nm diameter silica@zirconia NPs with monoclinic/cubic zirconia shell by a green, cheap and up-scalable sol-gel method. We studied the behavior of the particles upon water dialysis and found that the ageing of the zirconia shell is a major determinant of the colloidal stability after transfer into the water due to physisorption of the zirconia starting material on the surface. We determined the optimum conditions for adsorption of DNA building blocks, deoxynucleoside monophosphates (dNMP), the colloidal stability of the resulting NPs and its time dependence. The ligand adsorption was favored by acidic pH, while colloidal stability required neutral-alkaline pH; thus, the optimal pH for the preparation of nucleic acid-modified particles is between 7.0-7.5. The developed silica@zirconia NPs bind as high as 207 mg dNMPs on 1 g of nanocarrier at neutral-physiological pH while maintaining good colloidal stability. We studied the influence of biological buffers and found that while phosphate buffers decrease the loading dramatically, other commonly used buffers, such as HEPES, are compatible with the nanoplatform. We propose the prepared silica@zirconia NPs as promising carriers for nucleic acid-type drug cargos.