SPME涂层中硅烷化反应机理的研究

Mechanism of Gas-phase Silylation on Fiber Coating Following Solid Phase Microextraction

建立了 SPME涂层中硅烷化衍生化样品预处理方法 ,并用于葡萄酒中白黎芦醇的测定 .SPME硅烷化的反应动力学过程研究表明 ,涂层中硅烷化反应遵循假一级反应动力学 ,高温条件下硅烷化试剂会破坏极性聚丙烯酯 (PA)

The silylation of polar analytes on the polymeric coating of SPME fiber could be performed directly by placing the fiber into the headspace of bis(trimethylsilyl)trifluoroacetamide(BSTFA) after SPME. The derivatization was carried out at room temperature without damaging the fiber. Compared with the diazomethane SPME technique, it is a simpler, cheaper and environmental friendly. The kinetics of the reaction of silylation on SPME fiber coating was studied. The result indicated that the silylation was of pseudo first order kinetics. The reaction depends on the analytes concentration in the fiber coating. The experimental results also show that the new fiber coating has a high extraction efficiency for polar compounds but non reactive with derivatizing reagents could be found.