Summary: | 碩士 === 國立臺灣大學 === 化學研究所 === 93 === In this thesis, we focus on the impact of nanoparticles on the separation of biological molecules by capillary electrophoresis (CE) in conjunction with laser-induced fluorescence (LIF) detection. In the first part of this thesis, the impact of additives in 0.35% 2-hydroxyethyl cellulose (HEC, Mw 1,300 000 g/mole) on DNA separation by CE-LIF is studied. By using 0.35% HEC prepared in 40 mM glycine buffer (pH 9.9) containing 1% thiourea, 32-nm gold nanoparticles, and 1.27μM ethidium bromide, 9 DNA fragments with their sizes ranging from 394 to 653 bp were well resolved within 5 min. The separation is fast, highly efficient, and reproducible, mainly because of the change in HEC morphologies as a result of the interaction among thiourea, HEC, and gold nanoparticles. In the second part of this thesis, we have investigated the separation of biological amines and acids by CE-LIF using capillaries coated with poly-L-lysine (PLL) and silica nanoparticles (SiONPs). The capillaries coated with (PLL-SiONP)3 and (PLL-SiONPs)2-PLL are suitable for the separations of amines and acids, respectively. By using a (PLL-SiONP)3 capillary filled with a solution consisted of 10 mM formic acid (pH 3.7) and 3% acetonitrile (ACN), the limits of detection (LOD) at signal-to-noise ratio (S/N) = 3 are 1.2 nM and 35.0 nM for 5-hydroxyindole-3-acetic acid (5-HIAA) and 5-hydroxytryptamine (5-HT), respectively. The LODs are 0.09 nM and 19.0 nM for TA and 5-HIAA, respectively, when using a (PLL-SiONPs)2-PLL capillary filled with 10 mM formic acid ( pH 3.7). The practical application of the method has been validated by the analysis of urine samples, with great sensitivity, high speed, efficiency, and good reproducibility.
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