Organic and inorganic nanoparticles for imaging and sensing in water

Nanotechnology aims at the design, synthesis, characterization and application of materials and devices on the nanoscale. Nanoparticles are defined as materials with the three dimensions in the space less than 100 nm. They possess properties hugely different from the corresponding macroscopic materials. Their peculiarities depend on the reduced size, shape, composition and interface, all aspects that can be controlled during the synthesis. Moreover, nanoparticles can act as platforms for assemble well-defined multifunctional structures able to perform varied tasks. Nanoparticles can be made by inorganic materials and by soft materials. In the currently work a wide range of nanoparticles have been designed, synthesized and characterized for various purposes. In chapter 4 we propose simple and cheap strategy to develop multi-stimuli sensitive perylene diimide (PDI) molecules to create new smart materials by self-assembly. In chapter 5 we report synthesis of designed molecule that self-assemble in nanoparticles in biocompatible environment without any dramatic decrease of fluorescence brightness. In chapter 6 a similar work has been repeated with commercial fluorophores. Detection of chemical and biological agents plays a fundamental role in environmental and biomedical sciences. In chapter 7 small gold nanocluster functionalised with seven thiols in has been studied in presence active pharmaceutical ingredient (API). In chapter eight we try to increase melanin radiation protection activity both increasing number of stable free radicals and introducing oxidative ion transition metal. We have chosen Fe(III) and Mn(III) to increase oxidative ability and Zn(II), that do not possess oxidative ability as reference. We used 4-amino-TEMPO to increase number of stable free radicals.