Every cell is a miniature tuning fork. A sharp magnetic pulse makes it 'ring', and the decay of that sound depends on what's inside: viscosity, density, composition. A tiny diamond with a structural defect acts like a hypersensitive microphone, picking up magnetic echoes from individual cells.
This defect — a nitrogen vacancy — is so small that millions fit on the tip of a needle. Yet even a single center can detect the magnetic field of just a few protons.
Researchers tested two cancer cell lines. It turned out that each has its own, like a fingerprint, relaxation time for hydrogen nuclei: in more aggressive cells, the signal fades differently. Without chemical labels or dyes, often harmful to cells, the carbon-based sensor transforms signals from water molecules into a vivid diagnostic picture.
This non-destructive approach is a step toward the cell sorters of the future. They will be useful for finding rare stem cells, personalized diagnostics, and early disease detection.
Millions of diamond defects can fit on the tip of a needle, but even a single one detects the magnetic field of just a few protons.
Magnetic reading of cellular 'passports' resembles the workings of a medical tricorder from science fiction.