Here, we present a new and an easy to assemble dielectric barrier discharge plasma ionization source based on printed circuit boards with two parallel isolated electrodes for generating a plasma inside an inert fused silica capillary. For demonstration, this plasma source is coupled to an ion mobility spectrometer. With two different sample gas feeds the analytes can either pass through the plasma or bypass the plasma before entering the reaction region of the ion mobility spectrometer, allowing for different ionization pathways, e.g. electron impact ionization, ionization by excited species, e.g. helium metastables, or chemical ionization via reactant ions generated inside or downstream of the plasma. The plasma source, in particular, the electrode geometry and the capillary diameter were designed with the help of electric field simulations. A rectangular electrode with a height of at least twice the outer diameter of the capillary turned out to be ideal, in both the simulation and the experiment. Furthermore, a simple control electronics has been developed, which can be easily applied to other plasma sources. With the plasma source presented here, detection limits in the mid ppt_v range have been reached.

在这里，我们提出了一种新的且易于组装的介质阻挡放电等离子体电离源，该电离源基于印刷电路板，带有两个平行的隔离电极，用于在惰性熔融石英毛细管内产生等离子体。为了演示，该等离子源与离子迁移谱仪耦合。使用两种不同的样品气体进料，分析物可以在进入离子迁移谱仪的反应区域之前通过等离子体或绕过等离子体，从而允许不同的电离途径，例如电子碰撞电离，激发物质的电离，例如氦亚稳态，或通过等离子体内部或下游产生的反应物离子进行化学电离。等离子体源，特别是电极几何形状和毛细管直径是在电场模拟的帮助下设计的。在模拟和实验中，高度至少为毛细管外径两倍的矩形电极被证明是理想的。此外，还开发了一种简单的控制电子设备，可以轻松应用于其他等离子体源。使用此处介绍的等离子源，检测限在中等 ppt_v范围已达到。