Towards Low-Cost Magnetic Resonance Relaxometry

Magnetic Resonance Relaxometry is a powerful technique that reveals a sample's molecular dynamics thanks to the dependence of the T 1 relaxation time on field strength.With applications in protein research, food systems, material development, and environmental science, relaxometry measurements are typically undertaken using a technique known as fast field cycling, where T 1 is measured at a range of detection fields.However, the sample experiences relaxation in a variable field without the challenges associated with retuning a probe to each of the necessary frequencies of interest.This technique is limited by a maximum relaxation time, since the measurement and relaxation fields are typically applied using a fluid-cooled electromagnet, which will ultimately overheat for very long experimental times.In this work, we propose an alternative approach to permit measurements of samples with inherently long T 1 values.We utilise a broadband spectrometer alongside a solenoid transmit-receive coil and custom tuning and matching boards, whilst two sets of magnets are moved around the coil, to achieve a range of different fields.By collecting a reduced number of points and utilising this method, we show it is still possible to make useful measurements on samples at a range of frequencies, which has great potential in quality assurance applications.We find a similar trend for food samples of corn oil, while manganese chloride, a common contrast agent, has more than a 100% difference when compared to traditional fast field cycling measurements.