Diamond Sees Through the Cell ⚡ экспресс
Identifying individual cells in heterogeneous populations is critical for biomedical research and diagnostics. Existing sorting methods require reliable markers or can compromise cell viability due to labeling. A method based on quantum-enhanced NMR using nitrogen-vacancy centers in diamond is proposed for label-free detection of intracellular proton (^1H) signals. The method distinguished between two human tumor cell lines by the spin-lattice relaxation times T₁ of protons, serving as an intrinsic physicochemical signature. This lays the groundwork for label-free sorting in rare cell analysis, personalized medicine, and single-cell diagnostics.
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.