Golf-ball Assisted Atmospheric Pressure Ionization of Liquid Chromatography Tandem Mass Spectrometry for Analysis of Amino Acids in Complex Samples and Carotenoids in Food
| Autor: | Yen-Hsien Li, 李妍嫻 |
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| Rok vydání: | 2017 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 105 In this study, a universal home-made golf ball-assisted electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) for liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed to determine 20 trace amino acids in complex samples and 8 carotenoids in food. In this study we propose a novel method using a home-made golf ball positioned between the ion source and the inlet of the mass analyzer to hydrodynamically focus the ions passing through the golf ball to improve ion transmission. The results of the empirical experiments show that the ion plume of ESI passing through a golf ball could be focused on the inlet of the mass analyzer. The developed device can enhance the ion transmission efficiency and thus increase the signal intensity. The results showed that the analytical performance of the determination of the 20 amino acids in tea, urine and serum samples using the home-made golf ball-assisted ESI source is better than these obtained through commercial ESI source. The signal intensities of the 20 amino acids were enhanced by factors of 2-2700, 11-2525, and 31-342680 in Oolong tea, urine and serum analyses, respectively. The precision of the proposed method ranged from 1 to 9%, 0.4 to 9% and 0.4 to 8% at low, medium and high concentration levels of amino acids, respectively. A universal home-made golf ball-assisted atmospheric pressure chemical ionization for LC-MS/MS was developed to determine 8 carotenoids in food. The results demonstrated the analytical performance of the proposed golf ball-assisted APCI source is better than those obtained using the commercial APCI source. The signal intensities of the carotenoids were enhanced by factors of 2-7965 in food. The results showed low detection limits are obtained from 0.01 to 0.4 ng mL-1 with good linearity (10-1000 ng mL-1) and relative standard deviations less than 9%. The home-made golf ball-assisted ESI / APCI source not only can enhance ion transmission efficiency, but it is also an easy, convenient and inexpensive device. Form the results demonstrate that the golf-ball-assisted ESI /APCI system is highly effective in analyzing trace analytes in complex matrix. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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