Development of a Multi-purpose Electrospray-electron Impact Tandem Mass Spectrometer

Cody Hill


Mass spectrometry (MS) is ubiquitous in nearly all facets of chemical research and industry. Modern MS techniques include coupling various ionization schemes and sample introduction systems for multiple applications. Commercial devices that combine different types of ionization schemes and sample introduction systems are routinely available; however, are difficult to obtain at smaller, primarily undergraduate universities such as Humboldt State University (HSU) due to the high cost of these instruments. To solve the dual problems of instrument cost and flexibility, this presentation describes the proof of concept development and construction of an Electrospray Ionization-Electron Impact Tandem Mass Spectrometer (ESI-EITMS) at a fraction of the cost of a commercial instrument. This instrument, compared to commercially available instruments, will be novel and innovative, as it will be tailored to fit the needs of many applications. The ESI-EITMS will be capable of direct gas-phase injection electron impact tandem mass spectrometry, electrospray tandem mass spectrometry, and vacuum in-situ molecular beam photo-chemistry. Lastly, eventual goals for the instrument is to stream line the concept model to be able to take it outside the laboratory and perform real-time atmospheric analysis. Thus far a detector quadrupole (UTI 100C) has been implemented into a working tandem vacuum chamber, where a custom LabViewTM program has been written to digitize the data. The vacuum chambers are capable of reaching base pressures of 10–8 torr when closed and 10–5 torr when open to the atmosphere through a 50-micron pinhole and differentially pumped through 3 stages. Current work includes designing a skimmer system to reduce the pressure in the chambers when open to the atmosphere and implementing the mass selector quadrupole to work in tandem with the detector quadrupole through a series of Einzel lenses.


Mass Spectrometry; Electrospray, Vacuum

Full Text: PDF


  • There are currently no refbacks.