Towards Low-Cost Magnetic Resonance Relaxometry

Magnetic Resonance Relaxometry is a powerful technique which reveals a sample’s mo-lecular dynamics thanks to the dependence of the T1 relaxation time on field strength. With applications in protein research, food systems, materials development and environ-mental science, relaxometry measurements are typically undertaken using a technique known as fast field cycling where T1 is measured a given detection field, but 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 ap-plied using a fluid cooled electromagnet which ultimately will overheat for very long ex-perimental times. In this work we propose an alternative approach to permit measure-ments of samples with inherently long T1. 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 a more than 100% difference when compared to traditional fast field cycling measurements.