Time-of-flight mass spectrometry: Introduction to the basics

Abstract

The intention of this tutorial is to introduce into the basic concepts of time-of-flight mass spectrometry, beginning with the most simple single-stage ion source with linear field-free drift region and continuing with two-stage ion sources combined with field-free drift regions and ion reflectors-the so-called reflectrons. Basic formulas are presented and discussed with the focus on understanding the physical relations of geometric and electric parameters, initial distribution of ionic parameters, ion flight times, and ion flight time incertitude. This tutorial is aimed to help the applicant to identify sources of flight time broadening which limit good mass resolution and sources of ion losses which limit sensitivity; it is aimed to stimulate creativity for new experimental approaches by discussing a choice of instrumental options and to encourage those who toy with the idea to build an own time-of-flight mass spectrometer. Large parts of mathematics are shifted into a separate chapter in order not to overburden the text with too many mathematical deviations. Rather, thumbrule formulas are supplied for first estimations of geometry and potentials when designing a home-built instrument, planning experiments, or searching for sources of flight time broadening.

DNA adducts: Formation, biological effects, and new biospecimens for mass spectrometric measurements in humans

“…The employment of HRAMS can improve the confidence in adduct identification, eliminate interfering ion signals, and potentially provide sufficient mass accuracy to determine the elemental composition of the DNA adduct and its fragment ions. Time‐of‐ flight (TOF) provides several thousand up to 40 000 resolution . It is usually configured as MALDI‐TOF, MALDI‐TOF/TOF, and ESI‐Q‐TOF.…”

Resonance-enhanced Multiphoton Ionization Time-of-Flight Mass Spectrometry for Evaluating Emulsion Inversion via Temperature Change

“…REMPI-TOFMS is applied in a wide variety of fields, such as spectroscopic studies and environmental monitoring. [21][22][23][24][25][26][27][28] This method is normally used for the detection of samples in the gas phase with fewer applications to liquid samples. 29 In order to apply the unique features of this method to the measurement of an emulsion, we developed a sample introduction technique for REMPI-TOFMS that is based on the use of a pair of concentric capillaries.…”

Development of Multiphoton Ionization Time-of-Flight Mass Spectrometry for the Detection of Small Emulsion Droplets

“…Recently, we developed a version of multiphoton ionization time-of-flight mass spectrometry (MPI-TOFMS) for the direct analysis of an emulsion [13]. MPI-TOFMS has characteristics such as high selectivity and robustness [14,15] that make it suitable for the analysis of emulsions with inherently high concentrations of each constituent. MPI-TOFMS is normally applied to the detection of a gas sample [15][16][17].…”