He started his research activity with the study of photophysical
and photochemical properties of supramolecular systems, and in
particular of host-guest systems, catenanes, rotaxanes and
molecular machines. Moreover his attentions was devoted to the
study of energy and electron transfer processes in polichromophoric
systems, in particular containing porphyrinic macrocyles.
In the following years he started a very lively research
activity to design, synthesize and characterize new luminescent
chemosensors and labels for applications in the fields of
biological, environmental and alimentary analysis. In this
framework he has lately started to prepare and study metal and
silica nanoparticles to fully exploit the great analytical
potentialities offered by organized systems containing a large
number of dyes.
During his research studies in the first years of his career he
gained a great expertise in photophysical and photochemical
processes rising in complex supramolecular systems, dealing with
host-guest systems, catenanes, rotaxanes and molecular machines.
This know-how took him, in these last years to devote all his
attention to two very intriguing research fields: luminescent
sensing and photo-active nanoparticles and nanomaterials in
general, for environmental and medical applications.
Luminescent chemosensors: the development of chemical
sensors is dramatically changing the potentialities of chemical
analysis. Among the different chemical sensors, fluorescence-based
ones present many advantages: fluorescence measurements are usually
very sensitive, of low cost, easily performed, and versatile,
offering submicrometer spatial resolution and submillisecond
temporal resolution. A very fruitful approach that he is following
for the design of new efficient chemical sensors is based on the
principles of supramolecular chemistry. The supramolecular approach
typically entails the synthesis of molecules or supramolecules,
conventionally referred to as chemosensors, containing a receptor
unit and a so called “active unit”, that is able to signal the
interaction receptor-analyte with a significant change of one of
its chemical physical properties. He has developed many fluorescent
chemosensors for anions and metal ions both for biological and
environmental applications. Many of these species have also been
derivatized to be efficiently immobilized on surfaces (films on
glass, gold, quartz, etc.) or nanoparticles (metal and silica).
This allows to exploit the sensing ability of these species in
continuous and also for targets in the gas phase.
Photo-active Nanoparticles: nanoparticles have found many
industrial employments in a wide range of fields such as
electronics, optoelectronic, biomedical, pharmaceutical, cosmetic,
catalytic, and materials areas, in products such as
chemical-mechanical polishing, magnetic recording tapes,
sunscreens, automotive products, catalyst supports, biolabels,
electroconductive coatings, and optical fibres. In particular, his
research in the field of photoactive nanoparticles aims to the
development of innovative nanosystems for biological imaging,
medical diagnostics, and therapeutics. In this context, he has
developed a wide expertise in the synthesis and photophysical
characterization of metal (gold, and silver) and silica (also
core-shell and multilayered) nanoparticles functionalized with
suitable dyes, as labels for applications in the field of molecular
biology. Particularly new and interesting are the ‘mixed'
nanoparticles, i.e., with a metal core and a silica shell,
functionalized with luminescent moieties at different and selected
distances from the core, or with a silica dye doped core and a
surfactant biocompatible shell. The study of chemosensors based on
nanoparticles, with the possibility to obtain great signal
amplification effects, is yielding extremely interesting results in
the applications of these systems in medical diagnosis, analytical
multiplex imaging techniques and in general their exploitation in
biological imaging both ‘ex-vivo' and ‘in-vivo'.