Department of Experimental Physics, Comenius University in Bratislava, Mlynská dolina F2, Bratislava 842 48, Slovakia.
Anal Methods. 2022 Apr 7;14(14):1406-1413. doi: 10.1039/d2ay00186a.
An atmospheric Pressure Field Effect (APFE) ionisation source for drift tube ion mobility spectrometry has been developed for operation in positive and negative polarities. The formation of negative and positive ions in synthetic air was studied and compared with the Atmospheric Pressure Corona Discharge (APCD) ionisation source. The APFE ionisation source is of point-to-plane geometry with a 10 μm Pt point electrode, a stainless steel plate electrode and ultra-high resistance (20 GΩ) current limiters. In the case of negative polarity, the ionisation source was able to generate Reactant Ions (RIs) O(HO) and OCO(HO), and in the case of positive polarity, stable production of H(HO) RI was achieved in two different gas flow regimes of the IMS. RIs formed in the APFE in both polarities have made it a reliable chemical ionisation source at atmospheric pressure. The identification of the ions generated in the APFE was performed using an Ion Mobility Spectrometer coupled with an orthogonal acceleration Time of Flight Mass Spectrometer (IMS-oa-TOF-MS). The chemical ionisation of molecules was demonstrated for the APFE ionisation source in positive (2,6-di--butyl-pyridine) and negative (tetrachloromethane) polarities.
已开发出用于正、负极性操作的用于漂移管离子迁移谱的大气压场效应 (APFE) 离子源。研究了在合成空气中形成负离子和正离子，并将其与大气压 corona 放电 (APCD) 离子源进行了比较。APFE 离子源具有点-面几何形状，带有 10μm 的 Pt 点电极、不锈钢板电极和超高电阻 (20GΩ) 电流限制器。在负极性的情况下，该离子源能够产生反应物离子 (RIs) O(HO) 和 OCO(HO)，而在正极性的情况下，在 IMS 的两种不同气流模式下，能够稳定地生成 H(HO) RI。在两种极性下，APFE 中形成的 RIs 使其成为大气压下可靠的化学离子源。使用与正交加速飞行时间质谱仪 (IMS-oa-TOF-MS) 耦合的离子迁移谱对 APFE 中产生的离子进行了鉴定。对于正 (2,6-二-叔丁基吡啶) 和负 (四氯化碳) 极性，APFE 离子源演示了分子的化学电离。
