Applications of ambient ionization mass spectrometry in 2022: An annual review

Abstract

The development of ambient ionization mass spectrometry (AIMS) has transformed analytical science, providing the means of performing rapid analysis of samples in their native state, both in and out of the laboratory. The capacity to eliminate sample preparation and pre‐MS separation techniques, leading to true real‐time analysis, has led to AIMS naturally gaining a broad interest across the scientific community. Since the introduction of the first AIMS techniques in the mid‐2000s, the field has exploded with dozens of novel ion sources, an array of intriguing applications, and an evident growing interest across diverse areas of study. As the field continues to surge forward each year, ambient ionization techniques are increasingly becoming commonplace in laboratories around the world. This annual review provides an overview of AIMS techniques and applications throughout 2022, with a specific focus on some of the major fields of research, including forensic science, disease diagnostics, pharmaceuticals and food sciences. New techniques and methods are introduced, demonstrating the unwavering drive of the analytical community to further advance this exciting field and push the boundaries of what analytical chemistry can achieve.

Sample Injection for Real-Time Analysis (SIRTA) Using GC-MS with Cold EI

“…There are 85 different ADI methods and instrumentations as described in the literature . Among the various ADI methods, the most common are direct analysis in real-time (DART), desorption electrospray ionization (DESI), atmospheric solids analysis probe (ASAP), and open port sample introduction − as recently reviewed . The various ADI methods and instruments allow fast analysis of powders and organic surfaces without sample preparation through ambient (atmospheric) pressure desorption and ionization followed by ion transfer into the mass spectrometer through an ion funnel as used in LC-MS systems.…”

Magnetic Particle Spray Mass Spectrometry

“…However, complex samples can be a problem for AITs, due to the relevant interference of matrices and ionic suppression. 11 When an untreated complex sample is directly analyzed, a large number of concomitant molecules can compete with the analytes in the desorption/ionization step, resulting in low sensitivity, as well as insufficient precision and accuracy. 12 In this way, the association between AITs with sample preparation techniques is a very promising strategy for the analyses of small molecules (drugs, metabolites, and toxicants, among others) in complex samples, mainly with the use of solid phase extraction (SPE).…”

“…However, complex samples can be a problem for AITs, due to the relevant interference of matrices and ionic suppression . When an untreated complex sample is directly analyzed, a large number of concomitant molecules can compete with the analytes in the desorption/ionization step, resulting in low sensitivity, as well as insufficient precision and accuracy .…”

Arc-Induced Electrospray Ionization Mass Spectrometry

“…16 In addition, several other methods exist, including air flow-assisted ionization, wooden-tip ESI, and fast eruption desorption ionization. 17,18 The ionization technologies described above have unique characteristics and benefits. While suitable for microdroplet chemistry, their reliance on ESI-based processes may limit comprehensive analysis of diverse analytes.…”

“…Applying a 2.5 kV high voltage to a ballpoint tip creates a stable liquid coating on the metal ball, enabling the generation of charged microdroplets during droplet fission . In addition, several other methods exist, including air flow-assisted ionization, wooden-tip ESI, and fast eruption desorption ionization. , The ionization technologies described above have unique characteristics and benefits. While suitable for microdroplet chemistry, their reliance on ESI-based processes may limit comprehensive analysis of diverse analytes.…”