Nuclear Magnetic Resonance (NMR) Research
The Department operates a state-of-the-art 400 MHz Bruker AVANCE DRX-400 spectrometer.
Nuclear Magnetic Resonance (NMR) Spectroscopy
- Rapid verification of the identity and purity of raw material or product samples.
- Identification of a new substance or puzzling unknown obtained from a process or supplier.
- Quantitative analysis of the constituent(s) of interest in a sample.
- Identification and analysis of pharmaceuticals, fats and oils, polymers, detergents, organic constituents of cosmetics, household, industrial and food products.
- Analysis of petroleum samples including determination of % H and % C.
- Determination of water in samples.
Advantages of NMR Analysis
- Small samples i.e. low mg quantities of solid or liquid can be analyzed.
- The method is nondestructive.
- Little or no clean up is normally required.
- Analysis time is usually shorter than with conventional methods.
- In favourable cases, simultaneous determination of a number of components of a sample is possible.
- Substance of interest must contain a magnetic nucleus. In practice samples containing any or all of hydrogen, carbon, phosphorus of fluorine are included. Other magnetic nuclei can also be examined.
- Sample should be soluble in one of the following solvents: chloroform, acetone, benezene, methanol, dimethyl sulphoxide, water.
How NMR Spectroscopy Works
Most people know that matter consists of atoms and each atom contains a nucleus and electrons. Some nuclei are magnetic and they behave as tiny magnets. When a compound containing magnetic nuclei is placed in a magnetic field and a pulse of the correct radiofrequency (the same type of radio waves used to carry sound on the airwaves) is applied, the nuclei absorb energy and a set of signals or peaks, which constitute a “fingerprint” of the compound is produced.
The position, shape and area of the peaks in this NMR spectrum are directly related to the structure of the compound and hence can lead to its identification. Further, the area of any given signal in the spectrum is related to the amount of the compound present in a sample. This is the basis of the use of NMR in quantitative analysis.
Department of Chemistry, U.W.I., St. Augustine.
Phone: 1 868 662 2002 Extn. 82091/2 & 83570
Direct Line: 1 868 662 6013
Fax: 1 868 645 3771