Nanohybrids based on titanate nanotubes (TiONts) were developed to fight prostate cancer by intratumoral (IT) injection, and particular attention was paid to their step-by-step synthesis. TiONts were synthesized by a hydrothermal process. To develop the custom-engineered nanohybrids, the surface of TiONts was coated beforehand with a siloxane (APTES), and coupled with both dithiolated diethylenetriaminepentaacetic acid-modified gold nanoparticles (Au@DTDTPA NPs) and a heterobifunctional polymer (PEG₃₀₀₀) to significantly improve suspension stability and biocompatibility of TiONts for targeted biomedical applications. The pre-functionalized surface of this scaffold had reactive sites to graft therapeutic agents, such as docetaxel (DTX). This novel combination, aimed at retaining the AuNPs inside the tumor via TiONts, was able to enhance the radiation effect. Nanohybrids have been extensively characterized and were detectable by SPECT/CT imaging through grafted Au@DTDTPA NPs, radiolabeled with ¹¹¹In. In vitro results showed that TiONts-AuNPs-PEG₃₀₀₀-DTX had a substantial cytotoxic activity on human PC-3 prostate adenocarcinoma cells, unlike initial nanohybrids without DTX (Au@DTDTPA NPs and TiONts-AuNPs-PEG₃₀₀₀). Biodistribution studies demonstrated that these novel nanocarriers, consisting of AuNP- and DTX-grafted TiONts, were retained within the tumor for at least 20 days on mice PC-3 xenografted tumors after IT injection, delaying tumor growth upon irradiation.

Heterogenized metalloporphyrin catalysts for oxidation reactions are extensively explored to improve chemical production. In this work, manganese meso-tetraarylporphyrins were immobilized on hydrated mesoporous titanium dioxide (S_BET = 705 m² g⁻¹) through carboxylate or phosphonate anchoring groups separated from the macrocycle by the 2-arylimidazole linker fused across one of the pyrrolic rings of the macrocycle. The element composition of two mesoporous hybrid materials thus obtained were investigated and the integrity of the immobilized complexes was shown by different physicochemical methods. Finally, the catalytic efficiency of the more stable material Mn(TMPIP)/TiO₂ with the phosphonate anchor was evaluated in the selective oxidation of sulfides to sulfoxides by molecular oxygen in the presence of isobutyraldehyde (IBA). The heterogenized complex has shown excellent catalytic activity exhibiting a turnover (TON) of ~1100 in a single catalytic run of the sulfoxidation of thioanisole. The catalyst was successfully reused in seven consecutive catalytic cycles.

Mesoporous silica nanoparticles (MSNs) have attracted significant attention as a promising drug delivery platform for cancer treatment. However, their colloidal stability often remains overlooked, despite the numerous drawbacks associated with its absence. In this study, the enhancement of the colloidal stability of thoroughly characterised (TEM, DLS, zeta potential, TGA, XRD, N₂ physisorption) monodisperse MCM-41 MSNs in physiological conditions through the grafting a comb-like copolymer was successfully accomplished (preservation of the hydrodynamic diameter and the polydispersity index for at least 3 days). The loading of a therapeutic agent, cisplatin, was then achieved (12 wt%) without compromising their colloidal stability, and drug release kinetics were evaluated in cell culture medium, observing a complete release of the cargo after 48 h. Cytotoxicity studies conducted before and after drug loading confirmed the innocuousness of unloaded MSNs and demonstrated cytotoxic effects comparable to those of free cisplatin for the loaded nanoparticles (IC₅₀ = 23 and 13 μM CDDP for loaded MSNs versus 24 and 11 μM CDDP for free cisplatin in, respectively, SW480 and A549 cell lines). Particular emphasis was placed on ensuring the reproducibility of the results (e.g., hydrodynamic diameter and polydispersity index were measured across 49 independent synthesis) and on thoroughly evaluating the colloidal stability of the nanoparticles throughout the study, from synthesis to cytotoxicity assays. To the best of our knowledge, this work represents the first systematic study of the conditions required to develop stable colloidal suspensions of monodispersed mesoporous silica nanoparticles loaded with cisplatin, achieving high reproducibility, which constitutes a novel and robust contribution to the field.