NMR is well known for its ability to determine the chemical structure of molecules. The basic principle of NMR revolves around atomic nuclei, which have a quantum property called spin., which has an associated magnetic moment. While ¹³C or ¹H are the most common isotopes analyzed by NMR, other magnetic isotopes can be analyzed as well. When an external magnetic field is applied, the magnetic moment of the nuclei aligns with the external magnetic field, either with the field, a low-energy state, or against the field, a high-energy state.

Radio frequency electromagnetic radiation can cause nuclei to “flip” or transition to the high-energy state. When the radiation is removed, the relaxation to the low-energy state fluctuates the magnetic field, which produces a measurable signal. This signal is interpreted by Time-Domain–NMR (TD-NMR) by determining chemical composition based on the time domain data, without the high-resolution magnets required to Fourier transform to frequency-domain spectra in other NMR systems.

While not as powerful as and serving different functions than high-field NMR systems, TD-NMR systems have several advantages. Small, fixed magnets, which do not require the use of cryogens, power the analysis in TD-NMR systems. These small magnets allow for benchtop models, unlike the large magnets found in other NMR systems. Also, these systems are able to analyze complex mixtures, like whole seeds or polymers, with little to no sample preparation. They also offer analysis times ranging from a few seconds to a few minutes, making TD-NMR an attractive option for quick analysis of samples.

These instruments are used across several industries, particularly in QC  and research applications. In the food and agricultural industry, TD-NMR is used to determine solid-fat content, and oil and moisture content in a variety of products. In the pharmaceutical industry, TD-NMR allows for fast quantification of components in a drug sample or precision noncontact weighing. Polymers and petroleum products can also be analyzed for parameters like crystallinity or hydrogen content, respectively.

Bruker leads the market with its minispec series of TD-NMR systems. Oxford Instruments is the second largest supplier and offers the MQC+ and MQR product lines. CEM, Magritek and Niumag are also prominent suppliers. Many companies in this market produce whole systems, while some make spectrometers that can be used as a component in an TD-NMR system. Given the quick results produced by these instruments, automation seems to be the next step forward, an enhancement that Bruker and CEM now offer.

The total TD-NMR market in 2017 was over $100 million. Despite not being able to resolve molecular structure like larger NMR systems, the applications for these instruments keeps demand strong. The market is expected to experience solid growth in the future, driven by increasing government regulations in the food and agriculture industry, as well increasing usage by the pharmaceutical industry.

Leading Vendors

• Bruker
• Oxford Instruments
• CEM

Largest Markets

• Agriculture and Food
• Pharmaceutical
• Polymers

Instrument Cost

• $10,000–$100,000