Development of Chip-Based Open Channel Solid Phase Extraction Coupled to ICP-MS for On-Line Determination of Trace Elements in Microdialysates

• Main Authors: Chen, Wei-Yu, 陳威宇
• Other Authors: 孫毓璋
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/95673665109412867579

碩士 === 國立清華大學 === 生醫工程與環境科學系 === 97 === Abstract Nowadays, inductively coupled plasma mass spectrometry (ICP-MS) has become one of the most powerful trace elemental analytical techniques with high sensitivity as well as wide linear dynamic range and simultaneous multielement detection capability. However, the insufficient tolerance to the dissolved salts and polyatomic interferences always makes it difficult to directly analyze the high-salt content samples. Consequently, incorporating an efficient on-line pretreatment technique with ICP-MS is considered as an indispensable alternative to preconcentrate desired analytes and to minimize the adverse effects resulted from the concomitant matrices. To date, among the available on-line sample pretreatment methods, solid phase extraction (SPE) is particularly useful as a result of its simplicity and efficiency. For purpose of simplifying the analytical procedure and minimizing the volume of chemicals, in this study, a functionalized PMMA fluidic-chip as a solid phase extraction adsorbent was developed to couple with ICP-MS measurement. Recently, Lab-on-valve mesofluidic analytical system (LOV-MFAS) is a potential tool for the analysis of the real-world micro-samples. Based on literatures, the miniaturized SPE devices indeed provide the rapid response time and analytical capability because of its high surface-to-volume ratio and the short diffusion distance. Accordingly, we attempt to exploit a proper and effective SPE material namely functionalized poly(methyl methacrylate) (f-PMMA) for the extraction of trace metal ions, and to develop a mesofluidic SPE chip to eliminate the possible salt-interference resulting from sample matrices prior to ICP-MS measurement. In this study, a simple CO2-laser engraving technique was employed to machine PMMA substrates instead of lithographic techniques and to attain low per-unit manufacturing cost and rapid prototyping. According to our experiment, a hyphenated system of on-line Chip-Based Open-Channel SPE coupled to ICP-MS was successfully constructed for the determination of trace elements in samples of limited volume (5~10 μL). With optimized procedure, the analytical performance of proposed hyphenated system was examined for determining the concentrations of trace elements in standard reference materials (SRM 2670 and 1643e). Presently, we have connected microdialysis (MD) sampling and Chip-Based Open-Channel SPE-ICP-MS together to determine trace elements in the microdialysate samples. For purpose of establishing a physiopathological-related animal model of trace elements, the practicability of this hyphenated system was evaluated in vitro by monitoring the step change in the concentrations of analyte ions in an external microdialysis medium.