【作者】 刘文民；

【导师】 关亚风；

【作者基本信息】 中国科学院研究生院（大连化学物理研究所） ， 分析化学， 2006， 博士

【摘要】 固相微萃取技术(SPME)是一种无溶剂的样品前处理技术,作为SPME技术发展的一种类型,固态萃取搅拌棒技术(SBSE)由于其萃取相的体积比SPME的大50-250倍,在萃取过程中自身进行搅拌,提高了目标组分的富集倍数约10~2,降低了分析检测下限,适合痕量有机污染物的萃取分析。设计了SBSE专用热解析器,解析器内衬管为石英管,用气相色谱进样口对样品传输线进行加热,使解析下来的样品无损失全部转移到色谱柱中,利用分析柱头固定相的溶质聚焦技术和程序升温,使色谱峰形对称,没有出现额外的峰展宽现象。而且解析完全,没有残留,使用寿命长,成本低,适配于各种类型的气样色谱进样口和检测器。采用溶胶凝胶技术(Sol-gel)合成了SBSE萃取相,由于萃取相本身与其载体玻璃之间通过化学键结合,获得了耐高温和耐溶剂的特点,耐温达300oC,使用寿命大于50次。表面多孔结构增加了样品与萃取相之间的接触面积,加速传质过程,提高萃取效率。一次涂层可以获得30μm的涂层厚度,多次涂渍可以使涂层厚度加倍。合成的萃取相适合于多环芳烃和有机农药类物质的分析,与气相色谱(GC)配合检测限达到ng/L级。建立了复杂样品分析前处理方法——有机溶剂提取与SBSE相结合的方法。利用Sol-gel包埋技术对不含溶胶凝胶活性的乙烯基二甲基聚硅氧烷进行包埋,合成Fiber-SPME萃取相,提出了Sol-gel包埋理论即在高温老化阶段乙烯基聚合成网与溶胶网络相互嵌套,使制得萃取相最高耐温达300oC,使用寿命在100次以上。针对海量样品前处理所遇到的困难,提出了固态样品瓶萃取技术(VSPME),实现了海量样本的多点同时采集,同时并行处理,避免了样品采集后和运输过程中所引起的变化。实现了处理时间和过程与样品数量无关的技术。更多还原

【Abstract】 Solid-phase microextraction (SPME) is a simple and effective adsorption and desorption technique, which eliminates the need for solvents. As a new type of SPME, stir bar sorptive extraction (SBSE) has about 50-250 times more extraction phase than that of conventional SPME, resulting increase of enrichment factor up to 102. The stir bar coated with extraction phase is also used to stir samples during extraction. The SBSE technique is suitable for extraction of trace amount of organic compounds in food and environmental samples.A thermal desorption system (TDS), consist of a quartz liner and heaters, gas flow controllers, temperature control units, and a sample transfer line to the GC, was designed and evaluated. A 90 mm long stainless steel cylinder of 6.7mm I.D. and 12mm O.D. was used to hold the desorption liner and the transfer line. The transfer line was inserted directly through the injector septum into the GC pre-column about 20 cm deep. Desorption is complete and no carry-over is found. The device is compatible to all GC, and is robust and low cost.A sol-gel coating method for the preparation of bars used in sorptive microextraction was described. The extraction phase poly(dimethysiloane) (PDMS) was partially crosslinked with the sol-gel network, and the most part was entangled within the network. The thickness of coating layer is about 30μm by one coating process. Thicker coating layer can be realized by multi-coating process. The improved coating technology shows good thermal stability up to 300°C.Organophosphorus pesticides (OPPs) in vegetables were determined by stir更多还原