Mike Goodwin (@massspecpro.bsky.social)

OpenDMS: An Open-Source Approach to Differential Mobility Spectrometry Differential mobility spectrometry (DMS) is a powerful gas-phase chemical analysis technique that separates ions based on their differential mobility in an asymmetric electric field, offering high sensitivity and rapid analysis crucial for fields such as proteomics, metabolomics, and environmental monitoring. Despite its advantages, the widespread adoption of DMS technology has been hindered by the high cost, proprietary nature, and lack of flexibility of commercial systems. In this study, we introduce OpenDMS, an open-source differential mobility spectrometry system designed to be accessible, customizable, and cost-effective. OpenDMS is constructed using readily available components with fully documented designs and open-source software for data processing and visualization. We demonstrate the system’s performance through detailed dispersion plots and sensitivity analyses, achieving a theoretical limit of detection of 38 ppt and a resolving power of 1.57 at 10 ppb and 836 SV for an ethylbenzene monomer. The ability to interchange ionization sources, such as plasma and UV ionization, highlights the system’s versatility. Importantly, we demonstrate that doping is compatible with the OpenDMS with the use of acetone shifting the DMMP monomer peak. By providing an open-source platform, OpenDMS aims to provide a solid foundation for access to DMS technology, fostering innovation and collaboration within the scientific community and accelerating advancements in various scientific fields. https://pubs.acs.org/doi/10.1021/acs.analchem.5c00361