High-Throughput Chip-Based Solid Phase Extraction Coupling with Inductively Coupled Plasma-Mass Spectrometry for Online Determination of Trace Elements

• Main Authors: Hsieh, Cheng-Chuan, 謝政娟
• Other Authors: 孫毓璋
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/30122884080524470557

碩士 === 國立清華大學 === 生醫工程與環境科學系 === 99 === Although inductively coupled plasma-mass spectrometry (ICP-MS) is a very powerful technique for trace metal analysis, the sample concomitants often lead to significant spectral interference and/or loss of sensitivity during the determination process. Therefore, incorporating an efficient online pretreatment technique to ICP-MS is considered as an indispensable alternative to concentrate analyte ions and to minimize the adverse effects caused by the concomitant matrices. Among various sample pretreatment techniques, solid-phase extraction (SPE) method is generally superior in terms of their simplicity and efficacy. Over the past decade, several chip-based SPE techniques have been extensively applied to analytical works. Its unique characteristics of high surface-to-volume ratio and short molecular diffusion distance enable a new pretreatment paradigm that has the potential to effectively separate analyte species from sample matrix. Even so, the realization of high-throughput analyses for chip-based SPE techniques remains difficult and rare until now. In general, increasing the operation flow rate is straightforward for achieving high-throughput SPE procedures. However, microdevices used for high-throughput analyses are often limited to large increase in the hydrodynamic resistance with increasing operation flow rate. Also, complete mixing of two fluids (sample and buffer solutions) within a reasonable time is quite difficult due to the low Reynolds number on the micro scale. To overcome the limitations, in this study, a polytetrafluoroethylene (PTFE) bead was implanted into the mixing chamber to change the streamline of solutions for efficient mixing and then the chip-based SPE device which composed of circularly multichannel pattern was employed to carry out the SPE procedures. Based on our results, this hyphenated system could effectively eliminate the salt-interference resulted from the salt matrices and preconcentrate desired elements even the extraction flow rate was extremely high. In addition, dilute samples were further used to demonstrate the first successfully high-throughput on-chip SPE of trace metal ions from high-salt content samples.