Summary: | 碩士 === 輔仁大學 === 化學系 === 90 === Capillary zone electrophoresis chip (CE chip) with embedded electrode fabricated on Pyrex is efficient and extremely sensitive down to submicromolarity in its own right, if done properly and with judicious selection of fabricating processes in optimal conditions. The present state of the art is highlighted by sub-micromolar detection of catecholamines and theoretical plate number as good as 102850 plates/m: the former is indebted to the low noise tightly bonded electrode near the outlet, the latter is bestowed by the 8x40 μm trapezoidal micro trench which is etched in HNA solution. However, the bare CE channel although efficient enough for general purpose is inadequate for the separation of five catecholamines, modification of eluent by adding propanol may improve separation somewhat but sacrificing sensitivity and system stability. The inadequacy of selectivity may be greatly improved by employing MEKC with sodium dodecyl sulphate: results indicate well-resolved peaks for all five catecholamines emerged in 4 minutes with linear range extending from 1 to 250 μM with R2 better than 0.992. A channel cleaning procedure for maintenance is also proposed in this investigation to ensure its integrity, stability and reproducibity.
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