The Application Of Fluorescent Nanoparticles In Cancer Early Detection

Nowadays, with the vigorous development of the nanotechnology, some new subjects such as nanochemistry, nanobiology, nanomaterial, nanopharmic are fast developed too. Nano-material, which has unique effect including high ultra-small size effect, surface effect, macroscopic quantum tunneling effect and other excellent properties (mechanical, electrical, electrochemical, optical, magnetic and catalytic) because of their nanometer size, is widely used in many fields. The functional nanoparticles, which is an important embranchment of the nanomaterial, has become a hot study topic at present. The appearance of the functional nanoparticles makes the sample micromation compared to the traditional biosensor. Many studies indicate that the functional nanoparticles are the perfect tool, which can get life information in situ, in vivo and in real time. Therefore, the studies on the preparation and application of functional nanoparticles are significative. Based on the fluorescent silica nanoparticles doped with an organic dye (rhodamine B isothiocyanat, TRITC), we finished our work in following details:1.Using cyclohexane, n-hexanol, Triton X-100, TRITC and tetraethoxysilane(TEOS) as the main raw material, TRITC doped fluorescent silica nanoparticles with core-shell structure were prepared by the nucleation in microemulsion(W/O) and the coating through the hydrolysis of silane in microemulsion(W/O). The physical and chemical properties of core-shell nanoparticles have been characterized by using transmission electronic microscopy, luminescence spectrometer, et al. The factors affecting the formation of nanoparticles in the experiment process have been discussed, including the concentration of the core dye, the fluorescent dye leaching of nanoparitcles, et al. The results showed that the fluorescent characteristics of the core dye which was doped in the fluorescent nanoparticles did not change, we obtained the the nanoparticles of highest fluorescent intensity when the core dye concentration was 0.06 mmol/L, the fluorescent dye of the nanoparticles was high stability and did not leach easily.2. After the copolymerization of TEOS and N-(β-amimoethy1)-γ-amino-propyl- triethoxy-silane(AEAPS), the amino groups were introduced to the fluorescent(TRITC) nanoparticles'surface. The prepared amino-modified fluorescent nanoparitcles conjugated to the anti-HER2 antibody, which can bind specifically to the over-expressing HER2 cells—human ovarian carcinoma SKOV-3 cells, using the the bifunctional crosslinker glutaraldehyde. The early recognition and detection of SKOV-3 cells can be realized by using this functional nanoparticle. The results demonstrated that the method using this fluorescent nanoparitcle as labels in place of conventional fluorophore molecular has greatly improved in sensitivity, selectivity, and fluorescent stability in cancer cells recognition, the functional fluorescent nanoparticles can provide a new measure technique in biological assay.3. A new method with better stability and recur for determination of trace copper has been established based on the fluorescence quenching of the aqueous solution of TRITC doped fluorescent nanoparticles due to the presence of cupric ion. The experiment conditions of detecting copper were optimized. The new prepared nanoparticles solution 1 mL (3 g/L) was mixed with the copper solution in PBS buffer (pH 6.0), and the fluorescent intensity of the nanoparticles solution was measured after reacting 25 minutes. Under the optimum conditions, the coexist ion did not interfere the detection of Cu(Ⅱ) when the relative error is≤±5%, this method has a detection limit of 3.55×10-5 mol/L.