
doi: 10.1117/12.782429
Sionex Differential Mobility Spectrometer (DMS) sensors can be used as standalone detectors in many applications because of their outstanding sensitivity and selectivity. However, in applications like field screening for toxic chemicals and explosives, the number of possible interferents may be so high that additional separation becomes useful for identification and for quantitative measurement. For these cases, we have developed several different hybrid technologies. (1) DMS-IMS 2 integrates bipolar differential mobility ion filtration with IMS drift time measurement in IMS drift tubes, one tube for each ion polarity. (2)The Sionex GC-DMS (microAnalyzer) combines a pre-concentrator, a rapid and selective GC column that operates at high temperature in an air recirculation loop, and DMS ion filtration and detection. (3) Sionex DMS-MS interfaces have been developed for several types of mass spectrometers, and dramatically improve mass spec performance by filtering out unwanted species to reduce chemical noise and improve measurement accuracy. The Sionex DMS-IMS 2 first uses DMS to select positive and negative ions based on ion mobility variation with field (the α(E) function), then uses paired IMS sections to measure the low field mobility (K(0)). DMS separation depends on many properties including the distribution of internal charges, rigidity, and clustering. The IMS drift times depend on molecular size and conformation at low fields. A number of applications of this technology will be described, including CWA's, TIC/TIM, and explosives. The Sionex microAnalyzer GC-DMS system combines sophisticated preconcentration, thermal desorption, GC temperature ramping, and DMS separation and detection in a compact, portable and field-deployable package. The list of applications for this technology is growing rapidly, currently including CWAs, BTEX, H 2 S and mercaptans, and others. Sionex DMS-MS interfaces are being used to make quantitative measurements of biomarkers, including breath markers, biofluid markers, and cancer-linked agents. DMS-MS improves the performance / cost tradeoff for the mass spectrometer, greatly speeds analysis compared to LC-MS, and maintains measurement accuracy.
| selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 14 | |
| popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Average | |
| influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Top 10% | |
| impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Top 10% |
