posted on 2021-11-15, 20:05authored byBin Jiao, Huimin Ye, Xinwei Liu, Jiexun Bu, Junhan Wu, Wenpeng Zhang, Yunfeng Zhang, Zheng Ouyang
The development of miniature mass
spectrometry (MS) systems with
simple analysis procedures is important for the transition of applying
MS analysis outside traditional analytical laboratories. Here, we
present Mini 14, a handheld MS instrument with disposable sample cartridges
designed based on the ambient ionization concept for intrasurgical
tissue analysis and surface analysis. The instrumentation architecture
consists of a single-stage vacuum chamber with a discontinuous atmospheric
interface and a linear ion trap. A major effort in this study for
technical advancement is on making handheld MS systems capable of
automatically adapting to complex conditions for in-field analysis.
Machine learning is used to establish the model for autocorrecting
the mass offsets in the mass scale due to temperature variations and
a new strategy is developed to extend the dynamic concentration range
for analysis. Mini 14 weighs 12 kg and can operate on battery power
for more than 3 h. The mass range exceeds m/z 2000, and the full peak width at half-maximum is Δm/z 0.4 at a scanning speed of 700 Th/s.
The direct analysis of human brain tissue for identifying glioma associated
with isocitrate dehydrogenase mutations has been achieved and a limit
of detection of 5 ng/mL has been obtained for analyzing illicit drugs
in blood.