Dalton T. Snyder,† Christopher J. Pulliam,† Zheng Ouyang,‡ and R. Graham Cooks*,† †Department of Chemistry and Center for Analytical Instrumentation Development, Purdue University, West Lafayette, Indiana 47907, United States ‡Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States ■ CONTENTS Ambient Ionization and Sampling 2 Vacuum Systems 4 Analyzers and Configurations 6 MEMS and Other Alternative Fabrication Methods 8 Simulations 9 Electronics and Data Systems 12 Portable Systems 19 Mesoscale Systems 20 Planetary and Space Science Systems 21 Practical Applications 22 Expectations 23 Author Information 23 Corresponding Author 23 Notes 23 Biographies 23 Acknowledgments 24 References 24

Miniature and Fieldable Mass Spectrometers: Recent Advances.

We discuss miniaturization in mass spectrometry in terms of the mass analyzer, the mass spectrometer, and the total analytical system. Mass analyzer miniaturization has focused on ion traps. Decreases in mass analyzer size facilitate reduction of the sizes of the other components of a miniature mass spectrometer, especially the radio frequency electronics and vacuum system. Appropriate sample introduction systems are needed for performance optimization. The criteria by which a miniature mass spectrometer is judged include adequate performance in the traditional areas of resolution, detection limits, and specificity; ruggedness; reliability; and fully autonomous operation. Our discussion of the total analytical system emphasizes the removal of the bottleneck of sample preparation and suggests a solution to the combination of sampling, preconcentration, and ionization: ambient ionization methods. We also describe current miniature mass spectrometers.

Miniature mass spectrometers

A micrometer-scale ion trap, fabricated on a monolithic chip using semiconductor micro-electromechanical systems (MEMS) technology. A single 111Cd+ ion is confined, laser cooled, and the heating measured in an integrated radiofrequency trap etched from a doped gallium arsenide (GaAs) heterostructure. Single 111Cd+ qubit ions are confined in a radiofrequency linear ion trap on a semiconductor chip by applying a combination of static and oscillating electric potentials to integrated electrodes. The electrodes are lithographically patterned from a monolithic semiconductor substrate, eliminating the need for manual assembly and alignment of individual electrodes. The scaling of this structure to hundreds or thousands of electrodes is possible with existing semiconductor fabrication technology.

/pdf/ion-trap-in-a-semiconductor-chip-mi7n939cgj.pdf

Ion trap in a semiconductor chip

https://link.springer.com/content/pdf/10.1016%2Fj.jasms.2008.06.022.pdf

Hand-Portable Gas Chromatograph-Toroidal Ion Trap Mass Spectrometer (GC-TMS) for Detection of Hazardous Compounds

A wireless-controlled miniature rectilinear ion trap mass spectrometer system, total weight with batteries 5.0 kg, consuming less than 35 W of power, and having dimensions of 22 cm in length by 12 cm in width by 18 cm in height, is characterized. The design and construction of the mass spectrometer including mass analyzer, vacuum system, electronics system, and data acquisition and processing systems, is detailed. The mass spectrometer is compatible with various types of ionization sources including a glow discharge electron impact ionization source used in the internal ionization mode, and various atmospheric pressure ionization sources, including electrospray ionization, atmospheric pressure chemical ionization, and desorption electrospray ionization, which are employed for external, atmospheric pressure ionization. These external sources are coupled to the miniature mass spectrometer via a capillary interface that is operated in a discontinuous fashion (discontinuous atmospheric pressure interface) to ...

https://pubs.acs.org/doi/pdf/10.1021/ac801275x

Design and characterization of a multisource hand-held tandem mass spectrometer.

https://link.springer.com/content/pdf/10.1016%2Fj.jasms.2006.02.009.pdf

Miniature toroidal radio frequency ion trap mass analyzer

A syringe-like device (hereinafter “syringe”) that is operable by a single hand, wherein the syringe includes a plunger for ejecting and then retracting a fiber or filament used for the collection of solids, solids in suspensions and liquids, wherein the syringe includes a microchip embedded in the syringe housing, and wherein the microchip enables electronic chain of custody tracking of a sample from a point of origin through final analysis.

Single-hand operated syringe-like device that provides electronic chain of custody when securing a sample for analysis

A virtual ion trap that uses electric focusing fields instead of machined metal electrodes that normally surround the trapping volume, wherein two opposing surfaces include a plurality of uniquely designed and coated electrodes, and wherein the electrodes can be disposed on the two opposing surfaces using plating techniques that enable much higher tolerances to be met than existing machining techniques.

Virtual ion trap

The rapid and accurate detection and identification of chemi cal warfare agents and toxic industrial chemicals can be critical to the protection of military and civilian personnel. The use of gas chromatography (GC)  mass spectrometry (MS) can provide both the sensitivity and selectivity required to identify unknown chemicals in complex ( i.e. real-world) environments. While most widely used as a laboratory-b ased technique, recent advan ces in GC, MS, and sampling technologies have led to the development of a hand-porta ble GC/MS system that is mo re practical for field-based analyses. The unique toroidal ion trap mass spectrometer (TMS) used in this instrument has multiple benefits related to size, weight, start-up time, ruggedness, and power consumption. Sample separation is achieved in record time (~ 3 minutes) and with high resolution using a state-of-the-art high-performance low-thermal-mass GC column. In addition to providing a system overview highlighting its most important features, the presentation will focus on the chromatographic and mass spectral performa nce of the system. Results from exhaustive performance testing of the new instrument will be introduced to validate its unique robustness and ability to identify targeted and unknown chemicals. Key Words: ion trap, mass spectrometer, gas chromatography, SPME, field-portable, chemical detection, toxic industrial compounds, chemical warfare agents, GCMS

Advances in field-portable ion trap GC/MS instrumentation

A system and method for performing field-portable GC/MS measurements for the rapid sampling and measurement of high temperature boiling semi-volatile organic compounds in environmental samples, wherein other column bundles have cold spots that may prevent high temperature boiling semi-volatile components from eluting the GC column, this new design may eliminate those cold spots on the GC column.

Randall W. Waite

Papers

Miniature toroidal radio frequency ion trap mass analyzer

Single-hand operated syringe-like device that provides electronic chain of custody when securing a sample for analysis

Virtual ion trap

Advances in field-portable ion trap GC/MS instrumentation

Improved low thermal mass gc module