Laser Synthesis of Hybrid Nanoparticles and Coherent THz Sources for Applications in Nanomedicine
Project Status: 3 Approved without Funding
Duration in months: 36 months
Objective
Introduction and Objectives. The current project concerns the investigations of laser-matter interaction processes, specifically for production of hybrid nanoparticles/nanocomplexes and intense tabletop coherent THz radiation sources towards the applications in nano-bio-medicine and “Green Energy” production.
Coherent light sources and nanoparticles have enormous and revolutionary applications in the applied and fundamental sciences. Among the important applications one can mention nanomedicine, biotechnology, electronics, environmental and green energy related fields. Thanks to extraordinary physical properties nanoparticles are used as contrast agents for optical imaging and magnetic resonance imaging (MRI), tools for laser nanosurgery during the laser photoheating, ablation, soldering, welding procedures, and drug delivery by nanocontainers. Hence, it is of certain interest to synthesize novel nanoparticles with ultralow toxicity and possibly high optical/magnetic response as contrast agents for the development of ultrasensitive diagnostic techniques.
The terahertz band lying between the microwave and infrared regions of electromagnetic spectrum has very low photon energy and thus it does not pose any destruction hazard for living biostructures. Radiation at these wavelengths is non-ionizing and subject to far less Rayleigh scattering than visible or infrared wavelengths, making it suitable for medical imaging applications in tissue depth. These unique features make terahertz imaging very attractive for medical applications such as tissue characterization and skin imaging, or distinguishing damaged organ from healthy one. Thus, for the advancement in THz bioimaging applications one needs high-power tabletop THz lasers and the implementation of new sources and mechanisms are of special interest in nanomedicine.
In the scope of the current project we propose to synthesize hybrid nanoparticles of extraordinary optical and magnetic properties by laser ablation method. These types of nanoparticles are of interest as contrast agents for the development of ultrasensitive multimodal laser spectroscopic and MRI diagnostics. Regarding the toxic properties of the MRI agents we propose a new way to create complex nanoparticles’ structures that are: toxic lanthanides atoms inserted in the body of the gold nanoparticles providing total nontoxicity in such hybrid nanostructures.
We also propose schemes of THz nanolasers which are unique, since the latters are based on the novel nanomaterials and the method of generation of THz emission - such as high harmonics radiation. Technical approach and methodology. The underpinning of the project is the utilization of novel approaches of synthesis of hybrid nanoparticles by laser ablation in liquids – a method developed by the leading team during the last years. Important advantage of this technique is the flexibility that allows producing a wide variety of pure metal-semiconductor-dielectric nanoparticles, as well as giving the unique opportunity to easily compose a large spectrum of hybrid nanomaterials. The technology of laser synthesis of nanoparticles is based on ablation/evaporation of a material to the phase of ionized plasma by focusing of ultrashort laser pulses to the surface of bulk target located in the liquid media. Hence, this method is a very efficient means to tune the nanoparticles’ physicochemical properties to a desired specific task. This method is extremely sensitive to such parameters of laser beam as energy and duration of pulses as well as wavelength of irradiation. During the project implementation picosecond and nanosecond lasers will be used. For each material the optimal conditions for nanoparticle production will be determined.
For implementation of high-sensitive optical and MR imaging it is planned to perform research and developments in the direction of production of hybrid nanoparticle complexes for enhancement of the luminescence and nonlinear optical responses will be achieved by using gold nanoparticle-semiconductor QD and graphene QD complexes. In this case the anomalous increase of the intensity of an optical signal for light emitting contrast agents under the plasmon resonance with the gold and graphene nanoparticles occurs. As a significant problem to produce nontoxic hybrid nanoparticle complexes for MRI we propose a way where magnetic resonance toxic contrast agents are inserted in body of gold nanoparticles by laser ablation in liquids.
For the theoretical analysis of nanostructures and hybrid nanoparticles synthesized under the laser irradiation we will extensively use Atomistix ToolKit and Virtual NanoLab Codes, which will allow calculating electronic structures of crystalline solids and nanosystems, their ground-state parameters, optical and mechanical properties. The problem of THz lasers will be treated by the solution of Maxwell and quantum kinetic equations on the base of the second quantized formalism.
