Ricerc@Sapienza

Purposely tailored thin film stacks sustaining surface waves have been utilized to create a unique link between emission angle and wavelength of fluorescent dye molecules. The knowledge of the thin film stack’s properties allows us to derive the intrinsically emitted luminescence spectrum as well as to gain information about the orientation of fluorophores from angularly resolved experiments. This corresponds to replacing all the equipment necessary for polarized spectroscopy with a single smart thin film stack, potentially enabling single shot analyses in the future.

We design a clinical splith-mouth, randomized controlled study, in which the retention of an opaque and clear pit and fissures sealants were evaluated and their effectiveness compared at 6 and 12 months of follow up. A secondary aim was to evaluate the possibility of using a fluorescence based intra-oral camera through the clear sealant to monitor enamel demineralization.

METHODS:

1,8-Naphthalimide-based imidazolium salts differing for the alkyl chain length and the nature of the anion were synthesized and characterized to obtain fluorescent probes for bioimaging applications. First, their self-assembly behavior and gelling ability were investigated in water and water/dimethyl sulfoxide binary mixtures. Only salts having longer alkyl chains were able to give supramolecular hydrogels, whose properties were investigated by using a combined approach of fluorescence, resonance light scattering, and rheology measurements.

Meso-tetraphenylporphyrin connected with a ferrocene molecule in the beta-position of the macrocycle through a triple carbon-carbon bond has been bound to carbon spheres using the Prato-Maggini reaction. The ethynyl or/and phenylene ethynylene subunits were chosen as a linking bridge to give a high conjugation degree between the donor (i. e., ferrocene), the photoactive compound (i. e., porphyrin), and the acceptor (i. e., carbon spheres).

A combined label-free and fluorescence surface optical technique was used to quantify the mass deposited in binary biomolecular coatings. These coatings were constituted by fibronectin (FN), to stimulate endothelialization, and phosphorylcholine (PRC), for its hemocompatibility, which are two properties of relevance for cardiovascular applications. One-dimensional photonic crystals sustaining a Bloch surface wave were used to characterize different FN/PRC coatings deposited by a combination of adsorption and grafting processes.

Photonic crystal enhanced fluorescence biosensors have been proposed as a novel immunodiagnostic tool, due to the increased fluorescence excitation rates and angular redistribution of the emission. Among these, purely dielectric one-dimensional photonic crystals (1DPC) sustaining Bloch surface waves (BSW) at their truncation edge, have recently attracted much interest. We report for the first time on the time resolved experimental study of the effects of excess reabsorption of the BSW coupled fluorescence in the near infrared range around 800 nm.

Background: Sentinel lymph node (SLN) mapping using Near-Infrared (NIR) Fluorescence Light is an increasingly used technique to improve nodal staging in several type of tumors, including gastro-intestinal, head and neck, breast and mel- anoma). The ultrastaging has a potential decision-making role in order to propose adjuvant chemotherapies in case of nodal micro-metastases. As a matter of fact, according to the last edition (8th) of the AJCC Cancer Staging Manual, the presence of LFN micro-metastases should directly be staged as N1 and no longer as N1mi.

Thymidine phosphorylase (TP) is an enzyme that is up-regulated in a wide variety of solid tumors, including breast and colorectal cancers. It is involved in tumor growth and metastasis, for this reason it is one of the key enzyme to be inhibited, in an attempt to prevent tumor proliferation. However, it also plays an active role in cancer treatment, through its contribution in the conversion of the anti-cancer drug 5-fluorouracil (5-FU) to an irreversible inhibitor of thymidylate synthase (TS), responsible of the inhibition of the DNA synthesis.

Anthracyclines self-assemble in water into dimers. In the presence of sufficiently high salt (NaCl) concentrations, solutions of the antibiotic doxorubicin, but not those of the closely related molecules daunomycin and epirubicin, turn into gels barely compatible with the presence of small oligomers. The use of spectroscopic, scattering, imaging and computational techniques, allowed light to be shed on the self-assembly process that triggered doxorubicin gelification.