Related Experiment Video
Updated: Jul 12, 2026
09:33
An Anaerobic Biosensor Assay for the Detection of Mercury and Cadmium
Published on: December 17, 2018
Summary
Cadmium-113 nuclear magnetic resonance (NMR) spectroscopy reveals molecular structure and dynamics. Varying temperature and magnetic fields ensures accurate analysis of relaxation and chemical shift data for inorganic and bioinorganic molecules.
Area of Science:
- Nuclear magnetic resonance (NMR) spectroscopy
- Bioinorganic chemistry
- Chemical dynamics
Background:
- Cadmium-113 NMR spectroscopy is a valuable tool for investigating inorganic and bioinorganic molecules.
- Understanding chemical dynamics is crucial for interpreting NMR relaxation and chemical shift data.
- Accurate data interpretation requires careful consideration of experimental conditions.
Purpose of the Study:
- To highlight the utility of Cadmium-113 NMR spectroscopy in structural and dynamic studies.
- To emphasize the importance of chemical dynamics in NMR data analysis.
- To demonstrate how varying experimental parameters enhances data reliability.
Main Methods:
- Utilizing Cadmium-113 nuclear magnetic resonance (NMR) spectroscopy.
- Performing experiments at various temperatures and magnetic field strengths.
- Combining solid-state and liquid-state NMR measurements.
Main Results:
- Relaxation data interpretation can be validated by temperature and magnetic field variation.
- Solid- and liquid-state NMR provide unambiguous chemical shielding data.
- Characterization of zinc and calcium ion binding sites in metalloproteins is achievable.
Conclusions:
- Cadmium-113 NMR spectroscopy, with careful experimental design, provides robust insights into molecular structure and dynamics.
- The study underscores the necessity of considering chemical dynamics for accurate NMR data analysis.
- This technique is effective for characterizing metal ion binding sites in metalloproteins.
Related Concept Videos
03:02Colors and Magnetism
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
01:10Carbon-13 (¹³C) NMR: Overview
Carbon-13 is a naturally occurring NMR-active isotope of carbon with a low natural abundance of 1.1%. In contrast, carbon-12 is the most abundant isotope of carbon with zero nuclear spin. Therefore, it is NMR inactive. The gyromagnetic ratio of carbon-13 is smaller than that of protons. As a result, carbon-13 resonance is about 6000 times weaker than proton resonance. For a given magnetic field strength, the resonance frequency of carbon-13 is about one-fourth of the resonance frequency for...
01:04¹³C NMR: ¹H–¹³C Decoupling
The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
01:21Tandem Mass Spectrometry
Tandem mass spectrometry is a technique that uses multiple mass analyzers in series to obtain a higher selectivity and reduce chemical noise during analyte detection. Instruments with multiple analyzers separated by an interaction cell enable secondary fragmentation and selected study of the fragment ions.Secondary fragmentations occur in the interaction cell and can be induced by various factors. Fragmentation induced by collision with inert gases, such as N2, Ar, He, etc., is called...
01:15NMR Spectroscopy: Chemical Shift Overview
The position of the absorption signal of a sample is reported relative to the position of the signal of tetramethylsilane (TMS), which is added as an internal reference while recording spectra. The difference between the absorption frequencies of the sample and TMS (in Hz) is divided by the spectrometer operating frequency (in MHz) to obtain a dimensionless quantity called the chemical shift. It is reported on the δ (delta) scale and expressed in parts per million.
For instance, the proton...
For instance, the proton...
01:20¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...