Controlling Room Temperature Phosphorescence Of Carbon Dot Based On Inorganic Crystals And Its Application

Regulating the triplet excitons of organic molecules has become an indispensable technology for photoelectric and photonics applications.Interestingly,organic molecules usually exhibit efficient room temperature phosphorescence(RTP)properties in the matrix.Carbon dot(CD)has excellent phosphorescence performance,good water solubility,high biocompatibility and low toxicity,which makes it become a better alternative material for organic phosphorescence.Embedding CD into the matrix(polyvinyl alcohol,amorphous silica and polyurethane,etc.)can improve the phosphorescence performance,but its matrix type is certain and difficult to select and adjust.The inorganic crystal elements have rich tunability,making them the best host for luminescent molecules.In this paper,the optical properties of Zn-CD/inorganic crystal nanocomposites are systematically controlled by simply changing the host inorganic phase,and the interaction between host and guest is explored.The application of Zn-CD/NaCl nanocomposites in boosting macrophage-driven host defense was further studied.The research content is as follows:1.Embedding Zn-CD into inorganic crystals(different content,crystal density,atomic number)by hydrothermally,it can activate and regulate its phosphorescence properties(strength,lifetime and efficiency).The two ways of Zn-CD embedded in the NaCl lattice and its the interaction were studied by means of solid-state13C nuclear magnetic resonance(13C NMR),high-resolution transmission electron microscopy(HRTEM)and confocal laser scanning microscope(CLSM).In summary,this simple synthesis strategy provides an advantageous way to prepare materials with specific phosphorescent properties.2.Based on the mechanism of high salt environment to activate the expression of nuclear factors of activated T-cells 5(NFAT5)protein to produce nitric oxide(NO),design the application of Zn-CD/NaCl nanocomposites in enhancing macrophage driven host defense.Due to changes in osmotic pressure and feedback mechanism,Zn-CD/NaCl can effectively promote lipopolysaccharide(LPS)-induced macrophage release of NO by 23%,thus resisting the invasion of external microorganisms.Furthermore,the experimental results show that the Zn-CD/NaCl composite can inhibit E.coli by 93%.Therefore,the low-toxic Zn-CD/NaCl nanocomposites can be used in bioimmunology and other fields.