用于昆虫外激素研究的微量顶空收集及热解吸气相色谱进样方法初探

A Simple Method for Analyzing Insect Pheromone at the Nanogram Level by Coupling Headspace Adsorption and Thermal Desorption Injection by Gas Chromatography with a Packed Syringe

描述了一个结合项空气流收集与无溶剂热解吸气相色谱进样的方法。用填充PorapskQ的微量注射器作为吸附管进行气流收集。将收集物不经溶剂洗脱直接进行热解吸进样。用人工合成的昆虫外激素化合物反-7-十二碳单烯乙酸酯（E-7-DA）及顺-5，反-7-十二碳二烯乙酸酯（Z-5，E-7-DDA）测定了方法的回收率，初步探索了运用于昆虫外激素分析的可行性，并讨论了提高回收率的途径。

This paper describes a simple device for analysis of insect pheromones by coupling headspace adsorption and direct nonsolvent thermal desorption injection by gas chromatography (GC). A microsyringe packed with Porapak Q as the adsorbent was mounted in the airway for enriching and collecting pheromones. After collection the microsyringe was inserted into a thermal desorption device which was coupled with a GC inlet port.The pheromone desorbed from the adsorbent was condensed on the cold head of the GC column and injected into the column by quickly increasing the temperature of the column oven. The synthetic compounds of insect pheromones, E -7-dodecyl acetate(E-7-DA) and Z -5, E -7-dodecadienyl acetate(Z -5, E -7-DDA), were used to determine the recovery of the method and to evaluate the utility of this device for GC analysis of insect pheromones at the nanogram level. The results demonstrated the potentials of this device for GC analysis of volatile components both on packed columns and capillary columns. The advantage of headspace collection is that it avoids interference from non-volatile contaminants and the advantage of nonsolvent thermal desorption injection is to avoid the lOss of pheromone while concentrating the eluted solution. The reported methed combines these two advantages. The author also discusses the ways to further improve the method.