Mini 12, Miniature Mass Spectrometer for Clinical and Other ApplicationsIntroduction and Characterization
journal contributionposted on 17.12.2015, 01:03 by Linfan Li, Tsung-Chi Chen, Yue Ren, Paul I. Hendricks, R. Graham Cooks, Zheng Ouyang
A benchtop miniature mass spectrometer system, Mini 12, with ambient ionization source and tandem mass spectrometry capabilities has been developed and characterized. This instrument was developed as a self-contained system to produce quantitative results for unprocessed samples of small volumes including nonvolatile analytes. The ion processing system, vacuum system, and control system are detailed. An integrated sample loading system facilitates automated operation. A user interface has been developed to acquire and to interpret analytical results for personnel who have limited mass spectrometry knowledge. Peak widths of Δm/z 0.6 Th (full width at half-maximum) and a mass range of up to m/z 900 are demonstrated with the rectilinear ion trap mass analyzer. Multistage experiments up to MS5 are accomplished. Consumable cartridges have been designed for use in ambient paper spray ionization, and the recently developed extraction spray ionization method has been employed to improve the quantitative performance. Monitoring of trace-levels of chemicals in therapeutic drugs, as well as in food safety and environmental protection operations is demonstrated. Dual MS/MS scans are implemented to obtain the intensities of the fragment ions from the analyte and its internal standard, and the ratio is used in quantitative analysis of complex samples. Limits of quantitation (LOQ) of 7.5 ng/mL, with relative standard deviations below 10%, have been obtained for selected therapeutic drugs in whole blood throughout their individual therapeutic ranges.
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Multistage experimentsvacuum systemuser interfaceion processing systemunprocessed samplesmass spectrometer systemion trap mass analyzersample loading systemMS 5mass spectrometry knowledgefood safetyCharacterizationA benchtopcontrol systemnonvolatile analytesmass rangeambient ionization sourcetandem mass spectrometry capabilitiesConsumable cartridgesextraction spray ionization methodpeak widthsLOQambient paper spray ionizationprotection operationsfragment ions