Summary: | 碩士 === 國立中興大學 === 化學系所 === 103 === To increase the sensitivity in Surface–enhanced Raman scattering (SERS) measurement with a minimal matrix effect for real–world sample analysis, a new method based on decoration of silver nanoparticles (AgNPs) on magnetic microspheres (MMs) was proposed. In the production of AgNPs decorated MMs (named Ag@MMs), iron oxide was first used to produce magnetic particles by co–precipitation method. These particles were further dispersed in water with a surfactant of oleic acid to form well separated micelles. These magnetic particles were further protected and stabilized by formation of cross–linked polymethylmethacrylate (PMMA) on the surface of the MMs. To increase the efficiency in adsorption of AgNPs and stability of AgNPs on MMs, the PMMA protected MMs were further functionalized with two classes of compounds; different chain length and different end functional group. These functionalized MMs (fMMs) were used to decorate AgNPs by photochemical reduction method. The fMMs offer much higher efficiency in decoration of AgNPs than that of none functionalized MMs. Also, amino compound gave the best SERS performance among the used compounds. Based on the scanning electron microscope (SEM) images, MMs produced in this work show a round shape with a size of 10 μm in diameter. Ag@fMMs prepared in this work were further applied to detect creatinine in urine sample. Highly sensitive and selective results were obtained.
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