Ionization Source
Ionization Source - Related Videos
03:12
Ionization Energy
0 Views •
2020
The amount of energy required to remove the most loosely bound electron from a gaseous atom in its ground state is called its first ionization energy (IE1). The first ionization energy for an element, X, is the energy required to form a cation with 1+ charge: The energy required to remove the second most loosely bound electron is called the second ionization energy (IE2). The energy required to remove the third electron is the third ionization energy, and so on. Energy is always required...
06:21
Imaging of Biological Tissues by Desorption Electrospray Ionization Mass Spectrometry
0 Views •
Cited by 21 •
2013
Desorption electrospray ionization mass spectrometry (DESI-MS) is an ambient method by which samples, including biological tissues, can be imaged with minimal sample preparation. By rastering the sample below the ionization probe, this spray-based technique provides sufficient spatial resolution to discern molecular features of interest within tissue sections.
07:31
Characterization of Recombination Effects in a Liquid Ionization Chamber Used for the Dosimetry of a Radiosurgical Accelerator
0 Views •
Cited by 2 •
2014
A growing number of radiation therapy devices offer the advantage of delivering the dose through very small beams to the tumor, allowing for increased conformity and higher doses per fraction. Many different detectors can be used for the dosimetry of these small fields. In the present study, the effect of ion recombination is investigated for a liquid ionization chamber using a stereotactic radiation therapy system.
10:04
Flame Experiments at the Advanced Light Source: New Insights into Soot Formation Processes
0 Views •
Cited by 4 •
2014
Gas sampling from laboratory-scale flames with online analysis of all species by mass spectrometry is a powerful method to investigate the complex mixture of chemical compounds occurring during combustion processes. Coupled with tunable soft ionization via synchrotron-generated vacuum-ultraviolet radiation, this technique provides isomer-resolved information and potentially fragment-free mass spectra.
08:54
Characterizing Bacterial Volatiles using Secondary Electrospray Ionization Mass Spectrometry (SESI-MS)
0 Views •
Cited by 40 •
2011
Secondary electrospray ionization mass spectrometry (SESI-MS) enables the detection of volatile organic compounds (VOCs) without the need for any sample pretreatment. This protocol provides instructions for the rapid (within minutes) characterization of bacterial VOCs using SESI-MS.
FAQs
Electron ionization removes electrons from analyte molecules, whereas chemical ionization can add protons or otherwise promote ion formation through chemical processes. These different routes influence the ions entering the mass analyzer and can change the extent of fragmentation. The choice therefore affects whether analysis emphasizes compound identification, structural information, or measurement of intact molecular species.
Ion formation conditions determine which charged species reach the mass analyzer and how extensively analytes break apart. Greater fragmentation can provide structural clues, while preserving larger or less-fragmented ions may support measurement of the analyte itself. Consequently, source selection must balance the desired information, signal strength, and the chemical properties of the sample.
The source prepares charged analyte particles and directs them toward the mass analyzer, while the analyzer evaluates their mass-to-charge ratios. These components perform different but connected functions: the source determines how analytes become observable ions, and the analyzer separates or measures those ions. Interpreting the resulting data requires considering both ion formation and mass-to-charge behavior.
Different source approaches support different ways of transferring analytes into the gas phase and forming ions. Electron ionization, chemical ionization, electrospray, and matrix-assisted laser desorption provide alternative routes for handling analytical targets. Selecting among them requires attention to sample properties and whether the experiment concerns small molecules, biomolecules, or complex chemical mixtures.
The workflow begins by introducing the analyte to a source that transfers it into the gas phase and forms charged particles through electron removal, proton addition, or another supported ionization process. The resulting ions are then directed into the mass analyzer, which measures their mass-to-charge ratios for subsequent identification, structural analysis, or quantification.
Comparison is useful when the sample’s properties or the desired analytical outcome could favor different ion-formation routes. Researchers may evaluate electron ionization, chemical ionization, electrospray, or matrix-assisted laser desorption according to their effects on fragmentation, sensitivity, and sample compatibility. Testing alternatives can help align the source with identification, structural, or quantitative goals.