ANYL 163 |
| The utilization of the core-shell composite nanoparticles as nano-sensing system to detect biomolecules has recently received much attention. In this study, SiO2/Au core-shell nanoparticles immobilized with urease to detect urea were fabricated. The monodisperse silica colloids were first obtained by hydrolytic sol-gel method. The particle surfaces were then covered with gold shell by the reduction of chloroauric acid in the presence of sodium citrate. The SiO2 particles with absorption peak at 213 nm were fabricated. SEM images confirmed the fabrication of 180-nm-core with 22 nm gold shell, creating a 527 nm absorption peak of core-shell particles. Moreover, urease and FITC were further immobilized on the gold surface by self-assembled monolayer. The developed core-shell biosensors showed high reproducibility, and the relative standard deviation was lower than 10 %. A good analytical performance with dynamic range of 2-3 orders of magnitude with the detection limit of lower than 0.2 mM was observed. In addition, the detection of heavy metals using the core-shell biosensors was also performed. |
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General Papers
7:00 PM-9:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster
Division of Analytical Chemistry |