Multiple Reaction Monitoring
Multiple Reaction Monitoring - Related Videos
11:49
Quantitative Proteomics Workflow using Multiple Reaction Monitoring Based Detection of Proteins from Human Brain Tissue
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Cited by 3 •
2021
The protocol aims to introduce the use of a triple quadrupole mass spectrometer for Multiple Reaction Monitoring (MRM) of proteins from clinical samples. We have provided a systematic workflow starting from sample preparation to data analysis for clinical samples with all the necessary precautions to be taken.
01:28
Multiple Halogenation of Methyl Ketones: Haloform Reaction
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2025
A method involving the transformation of methyl ketones to carboxylic acids using excess base and halogen is called the haloform reaction. It begins with the deprotonation of α hydrogen to form an enolate ion which reacts with the electrophilic halogen to give an α-halo ketone. The step continues until all the α protons are substituted to form a trihalomethyl ketone. The resulting molecule is unstable, and in the presence of a hydroxide base, it readily undergoes nucleophilic acyl substitution.
12:08
Monitoring the Reductive and Oxidative Half-Reactions of a Flavin-Dependent Monooxygenase using Stopped-Flow Spectrophotometry
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Cited by 12 •
2012
We describe the use of a stopped-flow instrument to investigate both the reductive and oxidative half-reactions of Aspergillus fumigatus siderophore A (SidA), a flavin-dependent monooxygenase. We then show the spectra corresponding to the species in the reaction of SidA and we calculate the rate constants for their formation.
12:34
Monitoring Plasmid Replication in Live Mammalian Cells over Multiple Generations by Fluorescence Microscopy
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Cited by 4 •
2012
A method of observing individual DNA molecules in live cells is described. The technique is based on the binding of a fluorescently tagged lac repressor protein to binding sites engineered into the DNA of interest. This method can be adapted to follow many recombinant DNAs in live cells over time.
09:04
Selected Reaction Monitoring Mass Spectrometry for Absolute Protein Quantification
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Cited by 15 •
2015
This protocol describes how to perform absolute quantification assays of target proteins within complex biological samples using selected reaction monitoring. It was used to accurately quantify proteins of the mouse macrophage chemotaxis signaling pathway. Target peptide selection, assay development, and qualitative and quantitative assays are described in detail.
FAQs
Selectivity comes from monitoring a defined pathway from one precursor ion to specific product ions. The precursor represents the selected molecular species, while the product ions arise after collision-induced dissociation. Observing the expected transition links the signal to the target analyte and helps distinguish it from other compounds present in a complex sample.
Collision-induced dissociation converts the selected precursor ion into fragment, or product, ions that can be monitored individually. These fragments provide information used both to identify the analyte and to support its measurement. Because the instrument follows defined precursor-to-product transitions, fragmentation connects molecular selection with targeted quantitative analysis.
MRM combines defined ion transitions with targeted measurement, allowing researchers to focus analysis on selected compounds rather than treating every signal in a sample equally. Its selectivity and quantitative performance are especially valuable when metabolites, peptides, proteins, pharmaceuticals, or biomarkers must be measured in complex biological matrices.
A typical workflow begins by defining the chemical compounds to be measured and their relevant precursor ions. The instrument selects each precursor, applies collision-induced dissociation, and monitors the specified product-ion transitions. The resulting transition signals are then used to identify and quantify the selected analytes within the sample.
Bioengineers may select MRM when they need precise, targeted measurements from engineered biological systems or biological matrices. The method supports analysis of metabolites, peptides, proteins, pharmaceuticals, and biomarkers, making it useful for validating system behavior, assessing molecular changes, and examining whether engineered processes produce the intended analytical outcomes.
In drug metabolism studies, MRM can measure selected pharmaceuticals and related molecular changes, while biomarker research can focus measurement on defined disease-associated compounds. Its targeted design helps researchers evaluate these analytes within biological samples and generate reproducible measurements for studying metabolism, disease-related changes, and the performance of analytical workflows.