New Multi-color Fluorescent Nano-biological Materials And Research

This dissertation was carried out focusing on nontoxic fluorescence labeling. The applications of traditional fluorescence label: organic fluorescence molecular, quantum dot, rare earth fluorescence probe were reviewed. While all these labels are toxic and the emission wavelength are fixed, here we report two type of One-step synthesis of nontoxic multicolor fluorescence label, we have thus examined their fluorescence properties.1. A facile one-step synthesis of hydrophilic carbon dots from dehydration of stearic acid with sulfuric acid is reported. Without further surface modification, the carbon dots show multicolor photoluminescence. Also it has been found that the fluorescence intensity gradually grows with the increasing pH; meanwhile it can maintain at least 65% of that under neutral conditions in acidic condition. Moreover, the fluorescence intensity of the carbon dot is not sensitive to most metal ions, which could potentially be employed as biomarker in vivo with less toxicity and fluorescence quenching effect.2. Pink carbon-doped silicon dioxide were prepared by using concentrated sulphuric to dehydrate tetraethoxysilane. Chemical studies illustrates the produced materials contain C-O and C=O bonds due to the formation of C substitutional defect for Si when TEOS decomposed in the conditions of concentrated sulphuric. Also, the fluorescence center comes from the C substitutional defect for Si, the shifts of the PL peaks arise from different contents in different parts of the structure.