Synthesis Mechanism and Thermal Optimization of an Economical Mesoporous Material Using Silica: Implications for the Effective Removal or Delivery of Ibuprofen

Targeted delivery of AZD5363 to T-cell acute lymphocytic leukemia by mSiO2-Au nanovehicles

T-cell acute lymphocytic leukemia (T-ALL) is the most common cancer in children, with a low survival rate because of drug resistance and a high recurrence rate. Targeted delivery of chemotherapy drugs can reduce their side effects and improve their efficacy. The abnormality of phosphatidylinositol-3-kinase/protein kinase B/ mammalian target of rapamycin (PI3K/Akt/mTOR) pathway plays a key role in T-ALL occurrence. AZD5363 is a selective Akt inhibitor with promising therapeutic potential for tumors encoded by the PI3K/Akt/mTOR pathway. However, the toxicity and side effects have limited its application in treating T-ALL. This study aimed to design a delivery system for targeting AZD5363 to T-ALL by sgc8c aptamer designed as mesoporous silica (mSiO2) decorated with Au nanoparticles. The cell-specific targeting and cytotoxicity of mSiO2-Au-AZD5363-Apt were investigated. The mSiO2-Au nanovehicles were found feasible for AZD5363 delivery, with high loading efficiency and pH-responsive release in the acidic lysosome. More importantly, mSiO2-Au-AZD5363-Apt nanovehicles could specifically recognize and enter T-ALL cells in vitro and in vivo, effectively inhibiting the proliferation of CCRF-CEM cells. In conclusion, mSiO2-Au-AZD5363-Apt provided an effective therapeutic method for the targeted treatment of T-ALL.

Disiloxanes and Functionalized Silica Gels: One Route, Two Complementary Outcomes-Guanidinium and Pyridinium Ion-Exchangers

Five novel disiloxane compounds comprising guanidinium and pyridinium moieties were obtained with high yields and purity. The verified synthetic pathways were then applied for modification of pre-functionalized silica gel, producing materials with the analogous organic side-chains. These halide-containing compounds and materials were then compared as to their ion-exchange properties: two disiloxanes proved to be effective in leaching different anions (nitrate, benzoate and ascorbate) from solid to organic phase, and pyridinium-functionalized silica gels showed selectivity towards perchlorate ion, removing it from methanolic solutions with preference to other singly charged anions. The results presented demonstrate that both compounds and materials containing silicon-carbon bonds can be produced using the same methodology, but offer strikingly different application opportunities. Comparison of their properties provides additional insight into the binding mode of different anions and hints at how the transition from a flexible siloxane bridge to immobilization on solid surface influences anion-binding selectivity. Additionally, one of the siloxane dipodands was found to form a crystalline and poorly soluble nitrate salt (1.316 g/L, water), although it was miscible with a wide range of solvents as a hydrochloride. A possible explanation is given with the help of semi-empirical calculations. A simple, time- and cost-efficient automated potentiometric titration methodology was used as a viable analytical tool for studying ion-exchange processes for both compounds and materials, in addition to standard NMR, FT-IR and ESI-MS methods.