Background: Mass spectrometry (MS) is one of the most powerful
tools for chemical analysis by sorting fragment ions from analyte molecules
according to their mass. Vacuum ultraviolet (VUV) photoionization sources have
been used in MS to generate molecular ions of analytes. However, conventional methods
to generate VUV photons require either high power lasers or high voltage power
supplies which are usually very expensive. Thus, an inexpensive and versatile
photoionization source for MS is needed to achieve ion-generation and ion-transportation
at low temperatures and ambient conditions.
Technology:Inventors at Georgia Tech have developed a cost effective method to generate incoherent VUV photons using low temperature microplasmas-based devices, which can be integrated with a variety of MS components to offer many advantages over conventional mass spectrometers. The new innovative design of the integrated system of microplasma arrays with an open structured conical octopole ion guide (or other higher order radiofrequency ion guides) enables spatially resolved laser desorption and imaging measurements of a solid sample. The open structure of the octopole also allows rotational and translational positioning of a sample holder in the ion guide so that multidimensional analysis of samples can be achieved. Microplasma arrays with VUV transmitting windows can be further integrated with electron ionization sources to produce molecular ions and fragments simultaneously, which allows structural analysis in MS. The new integrated design provides a versatile platform for MS analysis under low vacuum or near ambient conditions, and its operating principle is fundamentally different from conventional ion guides such as ion funnels.
Commercial Applications: The new design can be incorporated with current MS systems to achieve high
performance and portability, which opens the door to a wide range of
applications in areas such as biology and biomedicine, cancer research and
studies of drug discovery, and surface chemical analysis.
Benefits / Advantages:
· New and cost effective design could lead to mass spectrometric imaging of solid samples at low vacuum or near ambient conditions.
· In-situ ion formation and ion transport through integration of microplasma arrays and octopole ion guides with electron ionization sources.
· Ability to image neutral molecules desorbing from surface and perform multidimensional analysis and structural analysis of solid samples.
· VUV photoionization enables ionization of molecules without substantial fragmentation.