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Fungi, molds, and algae are abundant in the environment, leading in many cases to different types of infections and diseases, such as immune suppression/reduced immune function, respiratory diseases, allergies, asthma, and superficial and subcutaneous infections (skin, keratinous tissues, and mucous membranes), among others. These organisms infect billions of people and cause millions of deaths worldwide, putting a massive and costly strain on healthcare systems. As such, there is an urgent need to develop safe and cost-effective continuous self-sterilizing systems to prevent bacterial and viral infections. Apart from polymeric or metallic systems, photocatalytic systems are currently being investigated, in particular photo-self-cleaning materials made of silver nanoparticle (AgNP)-doped titanium dioxide (TiO2). This chapter evaluates the photoactivity of commercial AgNP-doped TiO2 Porcelain Gres Tiles for preventing growth of fungi (molds) and algae on surfaces.

At the beginning of the industrial productions, porcelain gres tiles were considered as just a technical material, esthetically not very beautiful. Today thanks to new industrial production methods, both properties and beauty of these materials completely fit the market requests. Besides these noteworthy architectural features, new surface properties have been introduced in the last generation of these materials. In particular, deposition of TiO2 transforms the traditional ceramic into a photocatalytic eco-active material able to reduce polluting molecules present in air and water, to eliminate bacteria, and to reduce the surface dirt thanks to the self-cleaning property. The problem of photocatalytic materials resides in the fact that it is necessary an ultraviolet (UV) light source to activate the oxidation processes on the surface of the material, processes that are turned off inexorably when the material is illuminated by LED lights and, even more so, when we are in darkness. The commercial TiO2, which is used for the traditional photocatalytic coating, has been doped with metals in order to activate it even in the visible region and thus in the presence of sunlight or LED. The presence of dopant metals (patent WO2016157155), specifically Ag, also allows the material to work as well as antibacterial in the dark, by eliminating one of the negative features of photocatalytic building materials. This chapter will report all the material characterization and photocatalytic tests including antibacterial tests (under UV, LED, and in the dark as well), from the most common such as Escherichia coli to the most dangerous such as methicillin-resistant Staphylococcus aureus.

Highly toxic o-toluidine pollutant was photo-degraded in water by using ZnO nanoparticles. The tested powders were both commercial and laboratory-made, the latter obtained by means of two innovative synthetic procedures. The disappearance and the relative mineralization of the molecule were followed by HPLC/UV and TOC determinations, respectively. Intermediate products were identified by coupling LC/MS of the eluate after 3 h of reaction and ATR-FTIR analyses of the used ZnO powders at the end of photocatalytic tests. Selected degradation paths, characterized by different kinetic degradation rates, can be suggested as a function of the different surface texture, the effective photocatalytic active area and the e−/h+ recombination processes of the ZnO particles.

Mesoporous silica materials were modified with aminopropyl groups through post-synthesis grafting and the resulting samples were investigated as matrixes for controlled drug delivery. In particular we have investigated the influence of aminopropyl groups amount on the chemical-physical properties of obtained materials and on the drug adsorption-desorption processes.

Pure and modified silica materials were prepared by the sol-gel process and used as carrier for the controlled release of ibuprofen. A one-step synthesis was carried out for the preparation of the silica-drug composites and the sol-gel method was improved by using the ultrasounds in order to replace of acid or basic catalysts. It was found that the presence of methyl groups on the silica surface influences the drug delivery rate leading to a high degree of control of the desorption process.

Publisher Summary The aerogel synthetic method reported seems to represent a simple, easily accessible synthetic procedure for the preparation of Pt/ZrO2-SO4 catalysts, because everything can be done in one pot without the use of any special equipment. The specific conditions used for solvent evaporation, according to the aerogel synthetic procedure, are very stringent with respect to the determination of the analytical properties of the materials. This leads to a "homogenizing" effect with the removal of the "excess" sulfate and yields a constant surface concentration. In fact, the materials prepared have essentially the same amount of sulfate and the same surface area independently of the presence of platinum and the starting amount of sulfate. The morphology of the materials is predetermined by the solvent evaporation procedure. The crystal phase composition, the surface area, and the particle size of zirconia are essentially the same both before and after calcination and independently of the presence of platinum.