DIRECT SAMPLE ANALYSIS WITH AN ATMOSPHERIC PRESSURE GLOW DISCHARGE

DESCRIPTION (provided by applicant): The overall objective of this Phase I STTR project is the commercialization of a new ionization source for ambient mass spectrometry based on the flowing afterglow of an atmospheric pressure glow discharge (APGD). This technology promises to have significant impact in pharmaceutical, clinical and biomedical research and its potential for enabling in vivo mass spectrometry detection in combination with existing technology is real. There is an acute need for the development of new technologies which enable rapid measurements with minimal sample pretreatment. Minimizing up-front sample preparation increases sample through-put by reducing the time required to go from raw material to a result. The recent development of ambient mass spectrometry methods has already resulted in the successful commercialization of just a few of these disruptive technologies. This project involves the fundamental characterization, optimization and development of a new direct sampling technology for mass spectrometry based on the flowing afterglow of an atmospheric pressure glow discharge developed at Indiana University by Prof. Gary Heiftje. Atmospheric pressure glow discharges have been extensively studied but not until very recently has it been attempted to use an atmospheric pressure glow discharge for direct sampling of surfaces in the open ambient air. We envision commercial ion sources that can be easily converted among several atmospheric pressure ionization techniques and can be retro-fitted to several different types of mass spectrometers or ion mobility spectrometers. The specific aims of this Phase I STTR proposal are: Aim 1: Investigate the APGD and flowing afterglow chemical environment using spectroscopic techniques. Aim 2: Identify electrode structures and materials for the anode and cathode in an attempt to optimize the atmospheric glow discharge characteristics using the information gained through completion of Aim 1. An optimized cell will be one which maximizes reagent ion density and controls their spatial distribution. Aim 3: Operate the APGD cell in combination with mass spectrometry and identify operating conditions for the cell geometries investigated in Aim 2. Aim 4: Assess the feasibility for coupling APGD to a commercial laser ablation mass spectrometry system. Phase II of this project will include the development of a commercial prototype of the APGD ion source based on the criteria defined in Phase I, further optimization of its performance and robustness, comparisons to other ambient ionization methods and applications development in the areas of pharmaceutical and biomedical research. Specifically, Phase II will focus in part on the development of the APGD cell in combination with commercially available laser ablation mass spectrometry systems, which will enable direct, 3D molecular imaging of biological tissues. Other application areas that will be explored with the same instrumentation include high throughput screening of combinatorial libraries and in vitro cytochrome P450 assays. PUBLIC HEALTH RELEVANCE: Prosolia's new and versatile ambient ionization source for mass spectrometry promises to enable high throughput chemical screening that will significantly impact pharmaceutical, clinical and biomedical research.