Synthesis of core-shell Raman markers

• Main Authors: Wan-tze Chen, 陳菀澤
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/27758461621270957254

碩士 === 國立中正大學 === 化學所 === 94 === The common method for DNA detecting is using matrix surface to bind single-stranded DNA and to capture single-stranded complementary DNA. The combinatorial DNA microarray is one of this type of detection, but it costs a lot and is very time-consuming in manufacturing. Comparing colloid nanoparticle with the combinatorial DNA microarrays, we can see the colloid nanoparticle is cheaper in producing. Consequently, we adopt the method of the colloid nanoparticle instead of the method of the combinatorial DNA microarrays. Fluorescence dyes are commonly used as optical barcodes. However, while several fluorescence dyes are detected at same time, the peaks appear overlapped. In this research, we used surface-enhanced Raman scattering (SERS) spectra of dye molecules that absorb gold on nanoparticles as optical barcodes. We utilized the dye X-Rhodamine-5-(and-6) -isothiocyanate (XRITC) as the Raman marker and the aggregation agent of Au nanoparticle. Then, we capped a silica shell in the Au cluster surface to protect adsorbed dyes. Finally, we apply micoremulsion to produce one smooth and thick silica layer on the core-shell Au cluster, so that the silica surface is more effective for further functionization and Raman markers have the same size. We detect not only SERS spectra of bulk Raman markers, but also SERS spectra of single clusters that could be developed as biosensors.