Related Experiment Video
Updated: Jan 25, 2026
08:23
Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry
Published on: March 9, 2018
9.3K
ESI outcompetes other ion sources in LC/MS trace analysis.
Asko Laaniste1, Ivo Leito2, Anneli Kruve2
1Institute of Chemistry, University of Tartu, Ravila 14a, 50411, Tartu, Estonia. asko.laaniste@ut.ee.
Analytical and Bioanalytical Chemistry
|April 27, 2019
Summary
Electrospray ionization (ESI) and heated electrospray ionization (HESI) offer the lowest detection limits for pesticide analysis in LC-MS. Conventional ESI provides the widest linear ranges and is less affected by matrix effects than HESI.
Area of Science:
- Analytical Chemistry
- Environmental Science
Background:
- Selecting the right ion source is critical for successful LC-MS method development.
- Pesticide residue analysis in food matrices requires sensitive and reliable analytical techniques.
Purpose of the Study:
- To compare the performance of four different ion sources for LC-MS analysis of 40 pesticides.
- To evaluate ion source effectiveness in complex food matrices like tomato and garlic.
Main Methods:
- Analysis of 40 pesticides in tomato and garlic using liquid chromatography-mass spectrometry (LC-MS).
- Comparison of seven ionization modes: electrospray ionization (ESI), heated electrospray ionization (HESI), atmospheric pressure photoionization (APPI) with/without dopant, and a multimode source (ESI, APCI, combined ESI/APCI).
Main Results:
- ESI and HESI achieved the lowest limits of detection (LoDs).
- Conventional ESI without heated nebulizer gas exhibited the widest linear ranges.
- ESI showed significantly less matrix effect compared to HESI.
- APPI demonstrated minimal matrix effect, making it a suitable alternative to ESI when very low LoDs are not essential.
Conclusions:
- ESI and HESI are optimal for achieving low detection limits in pesticide LC-MS analysis.
- Conventional ESI offers superior linearity and matrix effect robustness.
- APPI is a viable alternative for pesticide analysis when matrix effects are a concern and extremely low LoDs are not the primary requirement.
More Related Videos
Related Concept Videos
01:10Mesh Analysis with Current Sources
2.0K
Mesh analysis becomes simpler when analyzing circuits with current sources, whether independent or dependent. The presence of current sources reduces the number of equations required for analysis. Two cases illustrate this:
Current Source in One Mesh: The analysis process is straightforward when a current source is found in only one mesh within the circuit. Mesh currents are assigned as usual, with the mesh containing the current source excluded from the analysis. Kirchhoff's voltage law...
Current Source in One Mesh: The analysis process is straightforward when a current source is found in only one mesh within the circuit. Mesh currents are assigned as usual, with the mesh containing the current source excluded from the analysis. Kirchhoff's voltage law...
2.0K
01:11Nodal Analysis with Voltage Sources
1.9K
Nodal analysis is a remarkably effective method used in electrical engineering to simplify the analysis of complex circuits, including those with dependent or independent voltage sources. Its strength lies in its systematic approach to breaking down circuits into manageable components, making it easier for engineers to understand and solve.
Consider a circuit that contains four resistors and two voltage sources, as shown in Figure 1. One of these voltage sources is connected between a...
Consider a circuit that contains four resistors and two voltage sources, as shown in Figure 1. One of these voltage sources is connected between a...
1.9K
01:12Electrospray Ionization (ESI) Mass Spectrometry
2.2K
Higher molecular weight biomolecules are nonvolatile compounds that may decompose before ionizing or vaporizing during mass analysis with conventional electron impact ionization methods. Accordingly, electrospray ionization (ESI) is the favored method for vaporizing and ionizing biomolecules as it circumvents rapid fragmentation and enables the recording of mass signals for the entire biomolecule.
ESI utilizes electrical energy to transfer ions from the liquid phase of the sample into the...
ESI utilizes electrical energy to transfer ions from the liquid phase of the sample into the...
2.2K
03:24Common Ion Effect
46.2K
Compared with pure water, the solubility of an ionic compound is less in aqueous solutions containing a common ion (one also produced by dissolution of the ionic compound). This is an example of a phenomenon known as the common ion effect, which is a consequence of the law of mass action that may be explained using Le Châtelier’s principle. Consider the dissolution of silver iodide:
46.2K
03:11Precipitation of Ions
30.0K
Predicting Precipitation
The equation that describes the equilibrium between solid calcium carbonate and its solvated ions is:
The equation that describes the equilibrium between solid calcium carbonate and its solvated ions is:
30.0K
01:19Ion Channels
91.2K
The movement of ions like sodium, potassium, and calcium into and out of the cell is essential to maintain the electrochemical gradient in living cells. The ion channels—a class of membrane transport proteins—help maintain this ionic gradient for the smooth functioning of physiological activities such as maintaining cell size and volume, conducting nerve impulses, and gas and nutrient exchange.
Ion channels are specialized integral membrane proteins on the plasma membrane that allow...
Ion channels are specialized integral membrane proteins on the plasma membrane that allow...
91.2K