| Details: |
Nanoparticle-based in vivo bioimaging and therapy demands the use of delivery systems that achieve their unaltered and unmodified delivery at the desired site in the body. In contrast to existing delivery strategies, we report the synthesis of hydrophobic and hydrophilic nanoparticles in the enclosed space of carbon capsules to develop a universal delivery system having single or multiple nanocontrast agents . The stability and inertness of carbon capsules in a wide range of reaction conditions such as high temperatures and harsh solvents were exploited for a variety of solution-based nanoparticle syntheses namely NaYF4:Eu3+(5%), LaVO4:Eu3+(10%), GdVO4:Eu3+(10%), Y2O3:Eu3+(5%) Pt, Pd, Ag and GdF3:Tb3+(5%). Furthermore, multiple types of nanoparticles such as GdF3:Tb3+(5%) (hydrophilic) and Y2O3:Eu3+(5%) (hydrophobic) were encapsulated inside the same carbon capsule to create a potential bimodal imaging agent (e.g. magnetic resonance imaging and fluorescence imaging). Polyethylene glycol (PEG) modified carbon capsules show excellent in vitro biocompatibility and bio-distribution in mice model. Further, in vivo study clearly suggests that these capsules have got good biodistribution and their accumulation in kidney which suggests these capsules can be cleared via renal pathway.
Metallic nanoparticles (MNP) are utilized as electrocatalysts, co-catalysts and photon absorbers in heterostructures that harvest solar energy. In such systems, the interface formed should be stable in a wide range of pH values and electrolytes. Many current non-thermal processing strategies rely on “physical” interactions to bind the MNP to the semiconductor. In this present work, we demonstrate a generic “chemical” approach for fabricating highly stable electrochemically/photocatalytically active monolayer and tailored multilayered nanoparticle structures using azide/alkyne modified Au, TiO2 and SiO2 nanoparticles on alkyne/azide modified silicon, indium tin oxide, titania, stainless steel and glass substrates via click chemistry. The stability, electrical, electrochemical and photocatalytic properties of the interface are exhibited via electrochemical water splitting, methanol oxidation and photocatalytic degradation of Rhodamine B (RhB) dye. Results suggest that the proposed approach can be extended for large-scale fabrication of highly stable heterostructured materials centric electrochemical and photoelectrocatalytic devices.
|