Related Experiment Video
Updated: Jul 8, 2026
08:49
Vegetated Treatment Systems for Removing Contaminants Associated with Surface Water Toxicity in Agriculture and Urban Runoff
Published on: May 15, 2017
10.5K
LC-IRMS Persulfate Oxidation: Case Study on Neonicotinoid-Related Structures
Felix Niemann1, Annika Gruhlke1, Maik A Jochmann1
1Faculty of Chemistry, Instrumental Analytical Chemistry, University of Duisburg-Essen, Essen, Germany.
Rapid Communications in Mass Spectrometry : RCM
|May 12, 2025
Summary
Optimizing liquid chromatography-isotope ratio mass spectrometry (LC-IRMS) oxidation is crucial for accurate carbon isotope analysis of neonicotinoids and similar compounds. This study reveals challenges and proposes a workflow for improved method development.
Area of Science:
- Environmental Chemistry
- Analytical Chemistry
Background:
- Liquid chromatography-isotope ratio mass spectrometry (LC-IRMS) is vital for analyzing stable carbon isotopes in polar nonvolatile compounds.
- Challenges exist with persulfate oxidation interfaces, especially for recalcitrant molecules like neonicotinoids.
Purpose of the Study:
- To systematically investigate the oxidation efficiency of neonicotinoid-related structures using a commercial LC-IRMS.
- To identify critical LC-IRMS parameters affecting carbon recovery and isotope accuracy for these compounds.
Main Methods:
- Evaluated neonicotinoid proxies for carbon recovery and δ13C accuracy.
- Varied LC-IRMS parameters including oxidant concentration, reaction time, temperature, acid concentration, and AgNO3 catalyst.
- Used an inorganic carbon standard for recovery/bias determination and EA-IRMS for normalization.
Main Results:
- Neonicotinoid derivatives showed low carbon recovery and significant δ13C bias.
- Optimized parameters improved recovery but did not eliminate isotopic biases.
- AgNO3 improved recovery but introduced δ13C variability; a workflow for identifying oxidation issues was proposed.
Conclusions:
- Optimization of LC-IRMS oxidation parameters is critical for accurate δ13C analysis of urea, guanidine, nitroguanidine, and related compounds.
- Systematic evaluation of oxidation efficiencies is necessary for optimal mineralization and precise isotope ratio determination.
More Related Videos
10:35Study on the Metabolism of Six Systemic Insecticides in a Newly Established Cell Suspension Culture Derived from Tea Camellia Sinensis L. Leaves
Published on: June 15, 2019
7.7K
06:11Determination of the Absorption, Translocation, and Distribution of Imidacloprid in Wheat
Published on: April 28, 2023
1.4K
Related Concept Videos
02:34Structural Isomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
02:52Stereoisomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
01:28Structures of Carboxylic Acid Derivatives
Structure of Carboxylic Acid Derivatives
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
01:19Structure of Amines
The hybridized nitrogen atom in amines possesses a lone pair of electrons and is bound to three substituents with a bond angle of around 108°, which is less than the tetrahedral angle of 109.5°. However, the C–N–H bond angle is slightly larger at 112°, with a carbon–nitrogen bond length of 147 pm. This carbon–nitrogen bond length of of amines is longer than the carbon–oxygen bond of alcohols (143 pm) but shorter than alkanes’ carbon–carbon bond (154 pm). These aspects are illustrated in Figure...
01:11Applications of IR Spectroscopy: Overview
The non-destructive nature and ability to provide valuable chemical information make IR spectroscopy a versatile technique with broad applications in various scientific and industrial fields. IR spectroscopy is commonly used to identify and characterize organic and inorganic compounds. It provides information about the functional groups present in a molecule and the bonding between atoms. This helps in the structural elucidation of compounds during organic synthesis, pharmaceutical research,...
01:28Structure-Activity Relationships and Drug Design
Drug design is a dynamic field that involves discovering and developing new medications based on specific biological targets. This process heavily relies on structure-activity relationships (SAR) and quantitative structure-activity relationships (QSAR) to guide the design and optimization of efficient drugs.
SAR studies the intricate relationship between a drug's chemical structure and biological activity. It focuses on understanding how modifications to a drug's structure can influence its...
SAR studies the intricate relationship between a drug's chemical structure and biological activity. It focuses on understanding how modifications to a drug's structure can influence its...