Nanomaterials are at the leading edge of the rapidly developing field of nanotechnology. Their unique size-dependent properties make them in some cases indispensable for advanced applications. The objective of this study will be focused on the synthesis of functionalized metal nanoparticles (MNPs) and nanostructured polymers (NPOLY), their characterization and applicative studies in optoelectronics and nanobiotechnologies. The project will be developed thanks to the multi-disciplinary skills of the participants, ranging from inorganic chemistry, physics, biophotonics and optoelectronics.
In the first step, MNPs (M = Au, Ag, Pt, Pd) will be prepared on purpose in the presence of different ligands. A wet chemical procedure will be applied to obtain stable colloidal suspensions. Selected dyes, drugs and bioactive agents will be immobilized onto the MNPs surface. Then the synthesis of NPOLY will be carried out in emulsion conditions, in the presence of vinylic monomers bearing functional pending groups, such as acrylic acid (AA) and methylmethacrylate (MMA) and different bioactive agents will be introduced during the synthesis. Dose profiling studies and a Monte Carlo simulation approach will be used to study the targeted delivery of bioactive molecules.
In the second step, MNPs and NPOLY will be deeply characterized in order to obtain information on composition, surface functionality and structure-property relationship. The use of different spectroscopic techniques (FTIR, UV-Vis, PL, NMR), microscopies (SEM, TEM, AFM) together with Light Scattering and Zeta Potential measurements will allow an accurate characterization of the nanoparticles, the determination of the surface morphology and the assessment of the hydrodynamic and electrical parameters. Moreover, optothermal and photoacoustic spectroscopies will be used to have spatial information about the optical absorption responsible for local heating, fundamental starting point for biophotonics studies.
The research topic on the design of new nanostructured materials, aimed to technological and biomedicine applications is one of the crucial area of research and of great strategic importance, also included into the Horizon 2020 program for the priority of Advanced Materials in Emerging Technologies (PE5. Synthetic Chemistry and Materials: Materials synthesis, structure-properties relations, functional and advanced materials, molecular architecture, organic chemistry). The design and study of new materials is based on an interdisciplinary approach and a close collaboration between researchers from different scientific fields is of fundamental importance. On these basis and supported by the international framing of the research programs, this project will be developed by a multi-disciplinary approach, based on complementary skills of the participants ranging from inorganic chemistry, physics, optoelectronics to biophotonics.
The innovation represented by this project is on the preparation of new materials, i.e. MNPs stabilized with organic or organometallic thiols and NPOLY based on vinyl monomers, and their use in in optoelectronics and biomedicine fields. The synthetic procedures for AuNPs will be applied to less explored metals, such as Ag, Pt and Pd. Hydrophobic and hydrophilic thiols will be chosen and introduced as single or mixed layers. The use of mixed ligands represents a challenging objective, still not deeply explored in the literature. Among others, dithiols will be used. These latter dithiols are really peculiar and new in the state of the art, with the potential to drive the self assembly of 2D or 3D ordered arrays. In these systems conductivity measurements represent a challenging objective aimed to investigate the electronic levels of MNPs and their potentiality in optoelectronics.
nPOLY will be prepared with mean size in the range 50-500 nm and this represent an innovation with respect to the state of the art, where nPOLY are often used with sizes more than 200 nm. The inclusion of bioactive molecules represents an innovative and really up to date objective that can be achieved thanks a bottom up approach. The loading, stability and release studies are of fundamental interest for nanobiotechnology studies and the proper choice of surface functionalities allow for example to immobilize hydrophobic biomolecules onto highly hydrophilic NPs. The use of NPs as drug delivery systems is one of the emerging field of nanomedicine and have a great potential impact on the development of new knowledge. The use of hydrophilic NPs can in fact be fundamental for the delivery of drugs with low solubility.
Optical studies based on photoacoustic and photothermal spectroscopies will allow to evaluate the optothermal properties such as thermal diffusivity, optical absorption independently from the scattering of the NPs based systems.
Dose profiling in hadrontherapy is a leading edge problem that has not yet a full solution and it is a limiting factor of the therapy. In particular the lack of in-beam control of the treatment forces to have short irradiation session repeated in time, that could be instead replaced by hypo-fractionation and a smaller overall duration of the treatment. Similarly, any innovation allowing for a larger effectiveness would reduce the dose to the healthy tissues of the patient and increase the potentiality of the treatment.
The possibility to exploit nuclear reactions of the impinging ions on nuclei for these purposes is yet unexplored and this innovative idea could open a new field of research. A feasibility study is needed as proof of principle before a full experimental plan, implying significantly larger investments, can start. This project is an opportunity for such a feasibility test. Also, it is to be noted as this topic is intrinsically inter-disciplinary and therefore this project could also serve to setup the required collaboration.
The development of this project consists of approximately 12 months. In a preliminary phase of 4-6 months the synthesis of MNPs and nPOLY pristine and in the presence of bioactive molecules will be carried out together with a their preliminary spectroscopic characterization. In a latter phase, selected and well defined systems will be used for fine characterizations and applicative tests.
The main element for the evaluation of the quality of the results lies in their dissemination and publication in international scientific journals with high impact factors. The participants in this research project therefore intend to submit their results to the scientific community through conferences and scientific journals. The participants are also involved in national and international research project applications.