Wednesday, March 21, 2018

URSP Student Benjamin McDowell Researches the Modification of Instrumentation to Emphasize the Detection of Volatiles

Volatile chemical compounds comprise the smells we experience on an everyday basis. My work, under the supervision of Dr John Schreifels, focuses on the modification of instrumentation to emphasize the detection of volatiles. Using mass spectrometry, individual volatile compounds can be identified and quantified, essentially an electronic nose. This semester’s focus aims to improve sensitivity by altering the interface between the low pressure mass spectrometer and ambient sampling conditions (atmospheric pressure). The modifications are designed to allow for implementation of electrospray ionization, an alternative to traditional ionization methods that works well for chemicals with a large vapor component. So far this has included assembling a detector capable of measuring ion flow through the aforementioned interface. Since high potentials must be applied to the sample for analysis, there are a variety of tunable parameters which can be experimented with. One of the most exciting parts of this is observing the vaporization that occurs with sufficient applied potential. Upon graduation this May I hope to pursue a graduate degree in Chemistry. A large portion of this will feature research similar to current projects. Generally, I am interested in the use of physical techniques in the analysis of molecular processes, which fits well with this project. One unexpected skill practiced in this project is 3D modeling. To better communicate various parts of the interface, I designed several of the components using the software Fusion 360. This allows for the individual parts to be assembled as they normally would, albeit with greater aesthetic than my machining skills can provide.