Researchers at the University of Warwick have unveiled a diamond-based magnetic field sensor that promises to revolutionise cancer detection and treatment.
This compact, ultra-sensitive device is designed to track magnetic fluids injected into the body, allowing surgeons to identify tumours and trace the spread of cancer more accurately.
One of the greatest challenges in cancer diagnosis is identifying when tumours have metastasised – spread from their original site to other organs, often through the lymphatic system.
Detecting whether cancer cells have lodged in the lymph nodes is crucial for planning effective treatment. Current methods, however, rely heavily on radioactive tracers or dyes, each carrying limitations.
Diamonds at the heart of the breakthrough
The Warwick team’s innovation lies in harnessing the unique properties of diamonds. These crystals contain nitrogen vacancy centres – defects that enable them to sense tiny changes in magnetic fields.
This property allows the diamond-based magnetic field sensor to detect magnetic tracer fluids made of iron oxide nanoparticles. Once injected into a tumour, the tracer fluid travels to the lymph nodes, mirroring the path of migrating cancer cells.
By pinpointing where this fluid accumulates, the magnetic field sensor helps surgeons identify which lymph nodes need removal, reducing the risk of cancer spread while sparing healthy tissue.
Compact, safe, and surgical-friendly
Unlike bulky equipment or radioactive tracers, Warwick’s diamond device is small enough for keyhole and endoscopic surgery.
The sensor head, measuring just 10 millimetres, houses a 0.5 mm³ diamond and a small
permanent magnet. This streamlined design removes the need for heavy electronics, making it portable and practical for clinical use.
Crucially, the system is non-toxic and non-radioactive, avoiding the risks associated with traditional methods.
Radioactive tracers require strict handling and are not available in every hospital, while blue dyes can trigger allergic reactions in a small percentage of patients.
The diamond sensor sidesteps both problems, providing a safer alternative without compromising accuracy.
Sensitivity that sets a new standard
One of the standout features of the Warwick magnetic field sensor is its extraordinary sensitivity.
It can detect just one-hundredth of a typical clinical dose of magnetic tracer fluid, giving clinicians far greater flexibility in how they approach tumour mapping.
This sensitivity is expected to improve further as quantum sensing technology advances.
Wider applications beyond breast cancer
While the current focus is on breast cancer surgery, the technology has far-reaching potential.
The same approach could be applied to lung, liver, colorectal, and oesophageal cancers, offering new hope for early detection and targeted treatment across multiple tumour types.
The researchers also believe the diamond magnetic field sensor could extend beyond medicine. Because diamonds respond to incredibly small shifts in magnetic fields, they may one day be used in spacecraft navigation or monitoring fusion power systems.
A game-changer in cancer care
The development of this diamond-based sensor marks a major step forward in non-invasive cancer diagnostics.
By replacing radioactive tracers and allergenic dyes with a safe, precise, and handheld device, Warwick’s innovation could reshape how surgeons trace tumours and stop cancer from spreading.
With clinician support already behind it and further research underway, this technology may soon move from laboratory breakthrough to standard hospital practice, potentially transforming outcomes for cancer patients worldwide.