Handheld Low-Temperature Plasma Probe for Portable “Point-and-Shoot” Ambient Ionization Mass Spectrometry

Wiley, Joshua S.; Shelley, Jacob T.; Cooks, R. Graham

doi:10.1021/ac4013286

Cited by 97 publications

(90 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While broad validation efforts have been undertaken for ambient ionization methods conducted on lab-scale MS instrumentation, such as the work of Gurdak and coworkers at National Physical Laboratory (NPL) in assessing inter-laboratory repeatability and constancy of DESI-MS [47], similar efforts utilizing portable MS systems for forensic applications have been limited to categorical assessments like limits of detection (LOD) and linearity [48,49]. Cooks and co-workers have assessed LODs for explosives residues [50,51] and drugs of abuse [52] using their lineage of miniaturized MS systems, as well as demonstrated quantitative toxicological analysis of biofluids [53,54]. Other reports have evaluated selectivity and throughput of drug evidence screening using commercially available systems [24,42].…”

Section: A Review Of the 2009 Census For Publicly Funded Forensicmentioning

confidence: 99%

Analytical Validation of a Portable Mass Spectrometer Featuring Interchangeable, Ambient Ionization Sources for High Throughput Forensic Evidence Screening

Lawton

Traub

Fatigante

et al. 2016

J. Am. Soc. Mass Spectrom.

103

View full text Add to dashboard Cite

Abstract. Forensic evidentiary backlogs are indicative of the growing need for costeffective, high-throughput instrumental methods. One such emerging technology that shows high promise in meeting this demand while also allowing on-site forensic investigation is portable mass spectrometric (MS) instrumentation, particularly that which enables the coupling to ambient ionization techniques. While the benefits of rapid, on-site screening of contraband can be anticipated, the inherent legal implications of field-collected data necessitates that the analytical performance of technology employed be commensurate with accepted techniques. To this end, comprehensive analytical validation studies are required before broad incorporation by forensic practitioners can be considered, and are the focus of this work. Pertinent performance characteristics such as throughput, selectivity, accuracy/precision, method robustness, and ruggedness have been investigated. Reliability in the form of false positive/negative response rates is also assessed, examining the effect of variables such as user training and experience level. To provide flexibility toward broad chemical evidence analysis, a suite of rapidly-interchangeable ion sources has been developed and characterized through the analysis of common illicit chemicals and emerging threats like substituted phenethylamines.

show abstract

Section: A Review Of the 2009 Census For Publicly Funded Forensicmentioning

confidence: 99%

Analytical Validation of a Portable Mass Spectrometer Featuring Interchangeable, Ambient Ionization Sources for High Throughput Forensic Evidence Screening

Lawton

Traub

Fatigante

et al. 2016

J. Am. Soc. Mass Spectrom.

103

View full text Add to dashboard Cite

show abstract

“…Although ion transfer could be achieved by increasing the gas flow rate and by utilizing much larger and powerful vacuum pumps, the size and power consumption of the MS instrument will suffer correspondingly. [50][51][52][53] In spite of these advantages, the use of a mechanical switch to control vacuum pressure and ion introduction duration lowers the scan speed, 13,47 stability, robustness of the system, especially when used in some on-site applications involving harsh environments. In a DAPI setup, high gas flow rate and efficient ion transfer are realized by mechanically opening the API for a very short duration (on the scale of milli-seconds).…”

Section: Introductionmentioning

confidence: 99%

Development of a miniature mass spectrometer with continuous atmospheric pressure interface

Zhai

Feng

Wei

et al. 2015

Analyst

104

View full text Add to dashboard Cite

The demand for on-the-spot analysis is met by a miniature mass spectrometer which is preferred to be robust, stable, as small as possible and capable of analyzing different samples by coupling with various ionization methods. However, largely constrained by the atmospheric pressure interface (API), these aspects are difficult to be realized in one system. Herein, we describe the development of a new miniature mass spectrometer with balanced performance. The miniature mass spectrometer is small in size (30 × 30 × 18 cm) but has a continuous API, which was achieved by high-pressure ion trap operation and maximized ion transfer efficiency with the utilization of a differential pumping system. The miniature mass spectrometer was characterized and optimized in terms of stability, sensitivity, mass range, mass resolution and scan speed. Rapid analysis of mixtures was demonstrated by coupling the miniature mass spectrometer with the ambient ionization technique of paper spray. This is the smallest miniature mass spectrometer to date, which has a continuous API.

show abstract

“…Gaseous analyte in the flow path is also sampled as in corona discharge APCI. Post-plasma sources in the form of a probe are also readily used in open air for portable or fieldable mass spectrometry trace detection systems [12].…”

mentioning

confidence: 99%

Humidity Effects on Fragmentation in Plasma-Based Ambient Ionization Sources

Newsome

Ackerman

Johnson³

2015

J. Am. Soc. Mass Spectrom.

View full text Add to dashboard Cite

Abstract. Post-plasma ambient desorption/ionization (ADI) sources are fundamentally dependent on surrounding water vapor to produce protonated analyte ions. There are two reports of humidity effects on ADI spectra. However, it is unclear whether humidity will affect all ADI sources and analytes, and by what mechanism humidity affects spectra. Flowing atmospheric pressure afterglow (FAPA) ionization and direct analysis in real time (DART) mass spectra of various surface-deposited and gas-phase analytes were acquired at ambient temperature and pressure across a range of observed humidity values. A controlled humidity enclosure around the ion source and mass spectrometer inlet was used to create programmed humidity and temperatures. The relative abundance and fragmentation of molecular adduct ions for several compounds consistently varied with changing ambient humidity and also were controlled with the humidity enclosure. For several compounds, increasing humidity decreased protonated molecule and other molecular adduct ion fragmentation in both FAPA and DART spectra. For others, humidity increased fragment ion ratios. The effects of humidity on molecular adduct ion fragmentation were caused by changes in the relative abundances of different reagent protonated water clusters and, thus, a change in the average difference in proton affinity between an analyte and the population of water clusters. Control of humidity in ambient post-plasma ion sources is needed to create spectral stability and reproducibility.

show abstract

Handheld Low-Temperature Plasma Probe for Portable “Point-and-Shoot” Ambient Ionization Mass Spectrometry

Cited by 97 publications

References 33 publications

Analytical Validation of a Portable Mass Spectrometer Featuring Interchangeable, Ambient Ionization Sources for High Throughput Forensic Evidence Screening

Analytical Validation of a Portable Mass Spectrometer Featuring Interchangeable, Ambient Ionization Sources for High Throughput Forensic Evidence Screening

Development of a miniature mass spectrometer with continuous atmospheric pressure interface

Humidity Effects on Fragmentation in Plasma-Based Ambient Ionization Sources

Contact Info

Product

Resources

About