Research Of Biological Sensors Based On Gold Nanoclusters And Immunofluorescent Test For Quantitative Detection Of CA199

Nano materials have unique physical and chemical properties, while traditional materials do not take on the superior performance. After Nano technology applied into the field of biological sensors, the sensitivity and other properties of the biological sensors improved, providing new opportunities the development of biological sensors. This paper based on the new nanomaterials with dynamic scattering method, electrochemical analysis and fluorescence linked immunosorbent assay from the following three aspects:1.A rapid Dynamic Light Scattering method for quantitative determination of DNA based on gold nanoclustersA rapid simple and convenient way to detect deoxyribonucleic acid by the dynamic light scattering method. This technique couples the large scattering cross section of gold nanoparticle probes as a light-scattering enhancer and dynamic light scattering (DLS) as identification system. The concentration of the DNA correlates to the size distribution of gold nanoclusters, by detecting the size change of the nanoclusters using DLS. The detection method showed good linear range and the detection limit. Dynamic light scattering method is rapid, simple, sensitive and provides a new method for detecting DNA.2、Direct electrochemistry and electrocatalysis of myoglobin immobilized on DNA-Gold Nanoparticle Clusters composite filmThe novel DNA-AuNP clusters were developed for effective immobilization and direct electrochemsitry of Mb. Owing to their excellent biocompatibility, good conductivity and large specific surface area, the DNA-AuNP cluster-based composite film provided a favorable microenvironment for high loading of Mb with retained biological activity, and greatly facilitated the direct electron transfer of immobilized Mb with the electrode. The prepared biosensor exhibited excellent performances for electrocatalytic reduction of H2O2with good stability and reproducibility.3、High sensitive and Quantitative detection of CA-199using upconversion nanoparticles based on fluorescence linked immunosorbent assay By the surface modification and activation for upconversion nanoparticles (UCPs), CA-199antibody could linked to the UCPs forms composite, further more, the application of composite in immunosorbent technology realized the fluorescence linked immunosorbent assay based on UCPs. The UCPs are excellent fluorescence label for the internal special properties, such as:near infrared irradiation、low autofluorescence、 narrow emission peak、large Stokes shifts. The detection method showed good linear range (125-4000U) and sensitivity.