Time Domain NMR (TD-NMR)
by specfit

Time domain NMR (TD-NMR) is a method to analyze samples using magnetic resonance. There are multiple advantages of TD-NMR.

  1. TD-NMR is a bulk method which penetrates the entire sample irrespective of solid, semi-solid, or liquid. Because the technique penetrates the entire sample, color, surface variation, and sample shape are not factors in the measurement.
  2. The signal response is uniform, regardless of chemical structure, so a hydrogen (1H) as water gives the same intensity signal as a hydrogen in a hydrocarbon chain.
  3. The signal response is linear, therefore, the number of calibration standards is small and can be as small as one standard with the second point through the origin.  Typically 4-6 calibration standards provide a robust method which account for secondary variations including error in the preparation of the standards.

The duration or lifetime of signals typically differ in the following way. Crystalline solids usually decay very quickly for tens of microseconds.  Non-crystalline solids or amorphous materials have signals which usually last slightly longer, perhaps 100 to 200 microseconds, followed by  semisolids like rubber and other soft materials, which might last for a few milliseconds and finally liquids have signals which can last for seconds.  Sampling the signal of a mixture of materials at different points reflects the concentration of each species. The figure below illustrates the differentiation of solid fat (a crystalline material) and liquid fat.  There are two measurements at 11 µsec (the total signal) and 70 µsec (liquid signal).


Solid fat content (SFC) by TD-NMR to rapidly measure the melting curve of edible oils
Measurement of Solid Fat Content depicting the measurement points for the total signal (solid+liquid) and the liquid signal for equal portions of solid and liquid components.

The decay behavior of the signal can also serve to characterize the authenticity of the sample.  For crystalline materials, changes in crystal packing due to processing have been found to correlate well with x-ray powder diffraction measurements.  A pulsed NMR instrument presents no adverse health risks, therefore it can be a preferred technique in production environment.

TD-NMR instruments are proton counting instruments.  Since each hydrogen (1H) responds the same as other hydrogens regardless of the structure (unlike methods like UV-Visible), TD-NMR is excellent for characterizing mixtures.


up to 18 mm sample tubes

SpecFIT HR50

up to 40 mm sample tubes

Specfit HR100 large format TD-NMR for samples up to 90 mm diameter

SpecFIT HRC100

4.5 MHz TD-NMR
up to 90 mm sample

specfit NMR for automated SFC by LAIX

Custom Automation

Uses the proven automation by LAIX Technologies.

The choice of the system is determined by application.

Find more info about NMR Applications

20 MHz specfit HR27


  • Solid Fat Content (SFC)
  • Finish on Fiber (FOY)
  • API content containing fluorine
  • Fluoride in toothpaste
  • Xylene solubles in polypropylene
  • Rubber/Mineral oil in polystyrene


  • Nominal field 0.47 T
  • Magnet gap 27 mm
  • 10 or 18 mm sample tubes
  • 250 W transmitter
  • Dimensions 26 x 14 x 17 in (w x h x d)
  • 185 lbs

The HR27 is a 20 MHz TD-NMR with 10 or 18 mm sample tubes shown with the retractable lifting bars so it can be readily lifted on the bench.

14 MHz specfit HR50


  • Oil and moisture content in oilseeds
  • Oil and moisture in palm nut
  • Oil and moisture in expelled palm cake
  • Relaxation (T1 and T2) measurements
  • Porosity and permeability measurements for porous materials including sandstone, carbonate, shale, concrete and engineered materials.


  • Nominal field 0.33 T
  • Magnet gap 50 mm
  • 10, 18, or 40 mm sample tubes
  • 250 W transmitter
  • Dimensions 26 x 14 x 17 in (w x h x d)
  • 185 lbs

14 MHZ for Hydrogen and 13 MHz for Fluorine
10, 18 and 40 mm diameter

4 MHz specfit HR100


  • Relaxation (T1 and T2) measurements
  • Product authenticity in finished bottles
  • Porosity and permeability measurements for native core including sandstone, carbonate, shale, concrete and engineered materials.


  • Nominal Field 0.1 T
  • Magnet Gap 100 mm
  • Maximum Probe size 85 mm
  • 250 W transmitter standard, 500 W optional
non-invasive detection of adulteration of olive oil using TD-NMR

Automation and Custom Probes

specfit and LAIX technologies partner to automate the operation of either the HR27 or HR50.  The robot is capable of working with dry tempering baths, an analytical balance, and other lab equipment for sample preparation. For more information, see the Fat Lab page for more ideas.  Contact us for a custom solution for your laboratory.

specfit can swap probes to accommodate a broad range of sample sizes customized for a particular application.


Results in seconds not hours by non-technical personnel


Eliminate extraction and the use of organic solvents


Minimum sample prep weigh and GO!


Compatible with reporting software for integration of results in automated record keeping and corporate information systems.

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