Kinetics of High Pressure Ionization Mechanisms to Enable Real-Time Ultra-Trace Detection of Organics from Environmental Matrices
Abstract
To minimize the complexities of field-based sampling and realize exháemely low levels of sensitivity, this project aims to characterize the kinetic routes of high pressure ionization mechanisms that enable ultra-trace level detection schemes using a kinetic reaction atmospheric flow tube (KRAFT). When combined with mass spectrometry (MS) this adaptive and selective ionization system will provide forensic investigators with a tractable, non-destructive, real-time methqd to quantify. chemical warfare agents (CW As), toxic industrial compounds (TICs), and their degradation products. However, until such goals are realized a fundamental understanding of ion clustering kinetics are required. Using a combination ofrapid gas-phase ion separations (i.e. ion mobility spectrometry (IMS)) and MS the proposed research will probe the central hypothesis that the1modynamics measurements can aid in the design of selective gas-phase reactions that produce stable ion clusters that are highly amenable to detection using MS. Identifying the conditions that produce selective ion cluste1ing, not simply charge háansfer, will directly aid the environmental forensics community while establishing the framework for highly adaptable and selective ionization schemes. The fundamental principles and technique developed under this research eff01i will be pursued across three specific aims. Specific Aim 1: High Pressure Them1odynamic Characterization of Gas-Phase Clusters of Common CWA and TIC Degradation Products. Building upon initial observations in the PI s laboratory the kinetics of cluster formation for select CW As along with their degradation products will be determined using an innovative KRAFT-MS system. Specific Aim 2: Design of Selective Adducts for Gas-phase Complexation. In order to extend the KRAFT-MS approach to a suite of TICs and toxic industrial mate1ials (TIMs) a logical series of competition experiments will be executed. This aim will leverage the results from previous project stages, employ computational chemistry techniques, and test the hypothesis that common functional groups found within target analytes may aid in the selection of ideal clustering agents. Specific Aim 3: Assessment of Detection Limits for Gas-Phase Ion Pairing Reagents from Complex Matrices. Serial dilution experiments will be performed to assess the detection limits, signal-to-noise ratio and required analysis time for each of the target chemicals using the range of selective adducts outlined in Aims 1 and 2. An additional goal of this Aim is to explore the simultaneous use of multiple gas-phase ion-pairing reagents for different chemical classes. At the completion of these studies, it is our expectation that we will have established the chemical foundations for a new class of analytical techniques aimed at the real-time detection of analytes relevant to the mission of the Army Research Office (e.g. CW A degradation products, decontamination solvents, and common ground water contaminants). Additional benefits of this approach include non-contact sampling and highly competitive detection limits ( < 1 ppm by volume in the gas-phase) using an innovative high-pressure ionization technique. Though initially tailored to CW A agents and their products, the underlying approach to establish the gas-phase properties of high-pressure ion clustering may be extended to other organics that are of interest. In addition to the education of students in the fields of analytical and physical chemistry, the broader reaching outcomes include peer-reviewed publications detailing the the1mochemical clustering information of target analytes in the gas-phase which is largely absent from existing literature. Additionally, it is envisioned that the KRAFT-MS approach to vapor detection may find utility in other disciplines such as biology and synthetic chemistry.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 12, 2017
- Source ID
- W911NF1510619
Entities
People
- Brian H Clowers
Organizations
- Army Contracting Command
- United States Army
- Washington State University