由于大部分环境样品的浓度非常低, 为了实现其直接检测, 提出将一种集成化的微型富集器应用到色谱系统中。富集器可实现色谱系统的进样与样品富集,能将色谱仪的检测限提高1~2个数量级。设计的富集器采用了高容量4平行通道结构,沟道内填充了高吸附率的Tenax-TA吸附材料,来实现对环境样品中挥发性有机化合物组分的富集。此外,为了密闭热解吸过程中所释放的组分,在微型富集器后集成了微型阀。试验结果表明,研制的微型富集器取得了15倍以上的富集因子。而且,通过微阀的控制,色谱峰的拖尾和峰展宽得到了有效的控制。因此,该微型富集器可广泛应用到环境样品的快速检测中,提高各检测器对复杂环境的适应能力。

The concentration of most environmental samples is very low. In order to directly detect these samples, an integrated micro pre-concentrator, which can significantly improve detection limit of mini gas chromatography system with 1-2 orders, is developed. The micro pre-concentrator has 4 parallel channels filled with enough Tenax-TA as adsorbent materials for concentrating volatile organic compounds. For closing the released components during thermal desorption process, a micro-valve is integrated behind the pre-concentrator. The result demonstrates the proposed pre-concentrator can effectively concentrate components with a concentration factor of 15. Moreover, the chromatography peak broadening is greatly compressed under controlling by the micro-valve. Therefore, the micro-fabricated pre-concentrator can be easy to deploy and suitable for a number of applications involving on-site monitoring of environmental samples.