ANYL 136 |
| The layer-by-layer (LBL) assembly technique is used to coat the stationary phase of MEMS-based preconcentrators for micro gas chromatography (GC). The thickness of the homogenous polymer and nanoparticle coating ranges from 10-500 nm; it can be easily controlled at the molecular level, along with manufacturing ease and low cost. Chemical properties of LBL films are tailored to enhance the separation resolution of complex gaseous mixtures. Coating embedded walls of a preconcentrator with layers of silica (45nm) nanoparticles provides a large surface area for interaction with and trapping of gas molecules. This reduction in the overall mass of the structure allows rapid thermal desorption to generate narrow bands for injection into GC columns. The preconcentrator is fabricated using a silicon-on-glass process, which minimizes system integration difficulties and, significantly, reduces the dead volume of the system and band broadening of the injected plug in the transfer lines. It helps reduce the separation speed by 3-4 times; making the separation of both n-alkanes from C5-C16 and polyaromatic hydrocarbons that vary in ring-size possible in less than 60s. |
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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 |