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A Mass Spectrometer Inlet Valve Synchronized to Pre-separated Sample Introduction

Description:

TECHNOLOGY AREA(S): , Chem Bio_defense 

OBJECTIVE: Develop or adapt a mass spectrometer based instrument with two-dimensional analytical capability with a “smart” inlet valve – the valve will open and admit a pre-separated analytical sample from atmospheric pressure, or near atmospheric pressure, only when the sample is presented to the mass spectrometer inlet. Pre-separated samples may be ionic species from an Ion Mobility Spectrometer (IMS) or neutral effluent from a Gas Chromatograph (GC). 

DESCRIPTION: Mass Spectrometry (MS) has been identified as a fundamental technology for analysis of molecular signatures to detect the presence of and identify chemical threat species in aerosol and vapor form. Mass spectrometers (also MS) operate under vacuum conditions and as a result, significant electrical power is expended to produce the vacuum. If a MS inlet can be controlled to open for a short time at precisely the time a pre-separated sample is present at the inlet, power consumption can be reduced. For example, if the inlet valve is open 10% of the time, only 10% of the MS gas load experienced with a continuously sampling inlet will have to be pumped. Development of a MS inlet synchronized to pre-separated neutral samples or pre-separated ionic species presupposes that the separation system is at or near atmospheric pressure. The sample separation system and the MS may be orthogonal technologies, e.g., gas chromatography and mass spectrometry (GC-MS) or complementary technologies, e.g., ion mobility spectrometry and mass spectrometry (IMS-MS). In a GC-MS instrument, neutral samples at or near atmospheric pressure are periodically introduced into the MS inlet with ionization occurring at a reduced pressure inside the MS. IMS-MS requires an ionization source external to the MS and ion (or sample separation) occurs at or near atmospheric pressure. The synchronized MS inlet would be keyed to a GC retention time of a sample of interest or to an ion species drift time in an ion mobility spectrometer. The key aspect of the solicited innovation is the synchronized MS sample inlet. Development includes mechanical design, electronic operation and software/firmware control of the synchronized inlet to minimize the MS vacuum requirements and reduce power consumption. Reducing vacuum requirements will prolong detector operation while utilizing battery power, smaller vacuum pumps can be used, and the vacuum envelope will be reduced in size. As advances in network architectures and decision logic mature, there is increasingly a need to quantify the concentration of a suspected threat plume in order to address the likelihood of a true positive detection event and to characterize the nature and extent of contamination or hazard presented by the incident. Recent developments have resulted small mass-based methods, i.e., ion mobility spectrometry and mass spectrometry, however, improvements in minimizing size, weight and power consumption can still be realized. 

PHASE I: The feasibility/proof-of-concept study will use a GC-MS or IMS-MS instrument operating on laboratory power with the synchronized MS inlet valve. Emphasis is placed on design, construction and operation of a synchronized MS inlet. Assessment of power consumption is paramount. The instrument may consist of commercial-off-the-shelf or specialized components in as small a form factor as possible with a projection of size, weight, power, sensitivity, and analytical resolving power of an instrument to be prototyped in Phase II. Vacuum pump size and power consumption will be minimized. Operational software will be developed to demonstrate the utility of the synchronized inlet. Key performance metrics associated with the technical approach will include low power consumption and will also include detection and identification of airborne chemical threats to include Chemical Warfare Agent (CWA) simulant (surrogate) compounds. Analytical system surrogate to surrogate compounds are directly indicative of responses to CWA. CWA responses would be accomplished in Phase II. 

PHASE II: The Phase II effort will fabricate, integrate, test, and optimize performance of a synchronized MS inlet as a part of a real-time two-dimensional vapor analysis platform based on the outcome of the Phase I analysis of the MS inlet and 2-dimensional instrument feasibility study. Offerors should perform quantitative assessment tests of the prototype platform using CWA simulant compounds. Chemical surrogates include high volatility, semi-volatile and low volatility compounds. Affordability, response time, and size, weight and power (SWaP) are critical evaluation criteria for the candidate technology. To be competitive and suitable for military threat monitoring, the technology must not cost more than $10,000 per system in production of 100s of units per year; must respond in 60 seconds or less, and not exceed SWaP constraints of one (1) kilogram (kg) including batteries, less than 650 cubic centimeters (cm3), and 24-hour operation using commercial off-the-shelf batteries. Offerors will make Phase II prototype instrumentation available to the appropriate DoD laboratory/facility to confirm quantitative assessment tests with actual chemical warfare agents to include, at a minimum, nerve and blister agents. Note, the Phase II prototype instrumentation cannot be returned to the Offeror. 

PHASE III: PHASE III: During Phase III, a real time, quantitative, multicomponent analytical capability will be finalized to enable the development of novel air-monitoring technologies suitable for defense and security applications and for industrial and commercial environments. The instrumentation will exist in portable form, powered by on-board commercial-off-the-shelf battery power. The instrument will have capability for sampling airborne analytes, vapors and aerosols. The capability to quantitatively define the concentration of gas phase constituents in real time would lead to new products for process and environmental quality monitoring in the pharmaceutical, semiconductor, and advanced materials industries. Additionally, the quantitative vapor/aerosol monitoring technology developed in conjunction with this SBIR topic would enable a wide variety of application models, to include compliance, safety and health, medicinal/diagnostic monitoring, and industrial/medical process monitoring. Offerors should enunciate a definitive commercialization strategy for gas monitoring and quantification technology including a market analysis for the DoD applications and other health and safety, environmental surveillance, diagnostic and industrial monitoring applications. PHASE III DUAL USE APPLICATIONS: The real time, quantitative, multicomponent enables development of novel air-monitoring technology suitable for applications in defense and national security, law enforcement (drug interdiction, drugged driving), and First Responder safety as well as applications for compliance, health and safety, environmental surveillance, diagnostic and industrial monitoring applications. 

REFERENCES: 

1: "A compact high performance ion mobility – linear ion trap mass spectrometer for high accuracy explosives and drug detection," Ching Wu, et al., 10th Annual Trace Explosives Detection Workshop, Ottawa, Ontario, Canada

2:  April 2018.

3:  "Miniature and Fieldable Mass Spectrometers: Recent Advances," Dalton T. Snyder, et al.

4:  Anal. Chem., 2016, 88 (1), pp 2–29.

KEYWORDS: Mass Spectrometry, Inlet Valve, Sample Introduction, GC/MS, Vapor Analysis 

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