| Summary: | 碩士 === 國立臺灣師範大學 === 化學系 === 101 === Compared to the chromatography paper currently used in paper-spray mass spectrometry (PS-MS), two series of “papers” were examined, including the papers that were made from natural and synthetic fibers, respectively. In the former case, 4 types of Japanese paper (Washi) were used, including Gampi paper, Tengujou paper, Glassine paper and Cicada paper, and the findings show that the limit of detection can be dramatic improved only when Gampi paper was used. This is because Gampi paper is very toughness and extremely thin (thickness, <20 μm) rather than the chromatography paper (thickness, >100 μm) and the others, leading to the sample solution much easier to be ejected and ionized toward the mass inlet. Since ionization occurs within a very short period (less than 30 seconds), an abundance of ions is formed, leading to a dramatic improvement in the limit of detection, at least 10-fold than the use of the chromatography paper. Due to natural fibers are difficult prepared in laboratory, in the case of synthetic fibers, 3 types of microtube array membranes were synthesized from polycarbonate (PC), polylactic acid (PLA) and cellulose acetate (CA) respectively, by means of co-axial electrospinning technique. The findings show that the limit of detection also can be improved, almost 10-fold, when the PC membranes were used. This is because PC membranes were thin (thickness, <70 μm), hydrophobic and sequence with the directionality, resulting to ionization occurs within a very short period (less than 1 min). Hence, as a rapid screening tool based on the PS-MS, both of the uses of Gampi paper and PC membrane were very useful. Furthermore, clear SEM (scanning electron microscope) photos of Gampi paper, PC membrane and chromatography paper were shown and discussed. Detailed information on how to synthesize PC membranes, the optimized position for ionization and its application for the analysis of a saliva sample are also reported.
|
|---|
