Field-portable, high-speed GC/TOFMS

Abstract

This work is focused on developing a fast gas chromatograph, time-of-flight mass spectrometer (GC/TOFMS) for man-portable field use. The goal is to achieve a total system solution for meeting performance, size, weight, power, cost, and ruggedness requirements for a laboratory in the field. The core technology will also be adaptable to specific applications including real-time point detection for hazardous chemical releases (e.g., chemical weapons), for biological agent signature identification, and for mobile monitoring platforms (e.g., air, ship, truck). Previously we presented results of a feasibility demonstration for a 30-lb field-portable TOFMS system. In this work we present recent progress in integrating a low-power, high-speed GC and show the capability for accurately recording fast GC transients for targeted compound detection using a quadrupole ion trap, time-of-flight instrument (QitTof). n this paper we review our progress toward developing a field-portable, high performance mass spectrometer (MS) system with applications to a variety of fast screening requirements. Previously we reported on a 30-lb class photoionization, quadrupole ion trap, time-of-flight system (PI/QitTof) [1]. More recently we have been developing a low-power, high-speed gas chromatography (GC) sampling system for the QitTof mass analyzer. The intent is to develop a compact system that can perform direct, real-time air and liquid sampling of targeted compounds in complex mixtures in a GC-bypass mode. If a targeted compound is detected during fast screening, the sample can then be subjected to GC/MS analysis for confirmation. This mode of operation achieves high-throughput molecular detection, while affording the option of confirming the results by GC/MS. We present here an overview of our field-portable MS program and then discuss future plans and directions.The focus of this instrumentation development is to develop a "laboratory-in-the-field" capability to conduct general environmental assessments [2] and a "rapid-response monitor" to quickly and accurately detect toxic compounds, such as chemical agents, resulting from leaks or releases. Other military applications include military force protection and chemical demilitarization. Civilian applications include high-profile event security, emergency first responder protection, and hazardous materials investigations. These applications require systems that can detect in real-time (1-10 s) a host of target compounds at ultralow concentrations (e.g., 1-100 ppb air sampling, 10 -100 pg residue) in the presence of a complex matrix that would otherwise obscure signals of interest due to overlapping signal.Several manufacturers have developed products for field applications with GC capabilities (e.g., Bruker's MEM line [3], Varian's Saturn Air); however, these are not man-portable. Viking Instruments, recently acquired by Bruker, offers a portable GC/MS (SpectraTrak) billed as a "real-time" monitor for toxic air, water, and soil pollutants; however, its portability is limited by weight...

Hand-portable gas chromatograph-toroidal ion trap mass spectrometer (GC-TMS) for detection of hazardous compounds

“…Major efforts have been made to miniaturize capillary GC [10 -14] and most MS analyzers, including time-of-flight (TOF) [15][16][17], quadrupole [18], magnetic sector [17][18][19], Fourier transform ion cyclotron resonance (FTICR) [20], and cylindrical [21][22][23], rectilinear [24 -26], and toroidal [27,28] ion traps. Most of these reports have concentrated on miniaturizing the GC column or the mass analyzer.…”

Mechanism of [M + H]+ formation in photoionization mass spectrometry

“…The introduction of compact, sensitive PI sources for commercial analytical MS instruments at atmospheric pressure (e.g., atmospheric pressure photoionization, APPI) [2,3,4] and sub-atmospheric pressure (e.g., low pressure photoionization, LPPI) [5,6,7] have opened up new applications and areas of research. APPI is by far the most widely utilized embodiment owing to the widespread use of LC/MS (for recent review articles see [8,9]).…”

Negative ion-atmospheric pressure photoionization-mass spectrometry

“…A tmospheric pressure photoionization (APPI) has recently been introduced as a new ionization method for liquid chromatography-mass spectrometry (LC-MS) [1,2]. In APPI the liquid sample is vaporized in a heated nebulizer similar to the one in atmospheric pressure chemical ionization (APCI) ion source.…”