Through a Glass Darkly: Glimpses into the Future of Mass Spectrometry

Abstract

The paper has three parts, (i) a brief overview of the main achievements made using mass spectrometry across all the fields of science, (ii) a survey of some of the topics currently being pursued most activity, including both applications and fundamental studies, and (iii) some hints as to what the future of mass spectrometry might hold with particular emphasis on revolutionary changes in the subject. Emphasis is given to ambient methods of ionization and their use in disease diagnosis and to their use in combination with miniature mass spectrometers for in-situ measurements. Special attention goes to the chemical aspects of mass spectrometry, including its emerging role as a preparative method based on accelerated bimolecular reaction rates in solution and on ion soft landing as a means of surface tailoring. In summary, the paper covers the proud history, vibrant present and expansive future of mass spectrometry.Keywords: ion chemistry, history of mass spectrometry, reaction rates, ion reactivity, mechanisms, instrumentation (Received October 12, 2012; Accepted October 16, 2012) Mass spectrometry may be defined, broadly, as the science and technology of ions. As such, it is a subject of enormous scope. The achievements of 20th century mass spectrometry now have come into focus. In rapid succession these include the measurement of mass/charge ratios of ions, 1) the discovery of isotopes, 2) and the utilization of isotope ratio measurements, 3) the measurements of mass defects, 4) and fundamental understanding of ionization, 5) fragmentation mechanisms 6) and the measurement of bond energies. 7) All this was achieved in the first half of the century and was made possible by advances in instrumentation including ionization methods, detectors and most importantly mass analyzers such as double focusing sector instruments. In the second half-century, organic mass spectrometry grew rapidly, starting with applications to petroleum distillates and moving quickly to natural products, steroids, and small-molecule drugs. 8) Gas chromatography/mass spectrometry was a key technology in early studies of biological systems. 9) Advances in instrumentation again fueled these advances, with ion optics becoming a significant scientific technology especially in Japan.10) A preoccupation with improving mass resolution and mass range became established and different types of mass analyzers were introduced for this purpose, including time-of-flight instruments 11) and quadrupole ion traps. 12) This quest drove biological mass spectrometry and propelled the development of ionization methods that were increasingly successful in handling both solid samples (desorption methods) 13)

Biomarker Characterization by MALDI–TOF/MS

“…Desorption electrospray ionization mass spectrometry, direct analysis in real-time mass spectrometry, and paper spray ionization mass spectrometry were respectively used to analyze dried blood spots and urine to diagnose inborn metabolite disorders or monitor drug levels [89][90][91][92][93][94]. In addition to analysis of biological fluids, AMS is an efficient technique for directly characterizing biomolecules in tissues for disease diagnosis or classification [95][96][97][98][99][100]. Fused droplet electrospray mass spectrometry, extractive electrospray mass spectrometry, and secondary electrospray mass spectrometry have been used to detect volatile disease biomarkers in breath [101][102][103][104][105][106][107][108][109][110].…”

A Field-Portable Membrane Introduction Mass Spectrometer for Real-time Quantitation and Spatial Mapping of Atmospheric and Aqueous Contaminants

“…The advent of portable chemical sensing technology has enabled a new framework for environmental monitoring, where it is possible to take high precision, high accuracy chemical measurements to the field [10][11][12][13][14][15][16][17][18]. Many of these analytical techniques, such as membrane introduction mass spectrometry (MIMS), can provide continuous monitoring time series data that resolve multiple analyte concentrations simultaneously [16,17,[19][20][21][22][23][24].…”