Compact Plasma Ionization for Ion Mobility Spectrometry Using a 4.3 MHz Miniature Tesla Coil

In this study, a low-cost 4.3 MHz plasma ionization source for ion mobility spectrometry (IMS), utilizing a miniaturized Tesla coil, is presented. This compact design, combined with a 3D printed cyclic olefin copolymer (COC) housing, delivers a stable and directed plasma suitable for ionization in IMS applications. The 3D printed housing ensures chemical resistance and low off-gassing, which are crucial for maintaining sample integrity. The Tesla coil produces a consistent sine wave at 4.3 MHz, and when connected to stainless steel screw electrodes it generates a stable plasma capable of ionizing analytes such as limonene, MTBE, nicotine, 2-octanone, and propofol. Measurements were conducted in both positive and negative ion modes. The results demonstrate the Tesla coil's effectiveness as a low-cost and reliable ionization source for IMS, offering comparable performance to traditional Ni⁶³ β-emitters. This advancement in plasma ionization technology could facilitate more accessible and flexible IMS systems for diverse analytical applications. The integration of 3D printing in the development of this ionization source underscores the potential for customized, low-cost analytical instrumentation, promoting innovation in laboratory environments and commercial applications.