Diamond Sensor Catches Magnetic Signal from a Living Cell ⚡ экспресс
Researchers combined an optical tweezer (laser trap) with a quantum magnetometer based on diamond NV centers—an ultrasensitive magnetic field sensor. This allowed them to precisely capture individual cells inside microchannels and measure their magnetic response. Instead of fluorescent labels, which suffer from bleaching and autofluorescence, they used magnetic nanoparticles: the signal from a labeled cell reached 89 µT, while the noise from an unlabeled one was only 3.9 µT. The contrast is like picking out a soft whisper in a silent room. The method opens the door to high-precision cell analysis without phototoxicity.
Biologists often tag cells with glowing molecules — it's like searching for a dim light in the smoke. The light quickly fades, and the smoke creates interference. Scientists replaced this approach with a magnetic compass: the cells received tiny magnetized particles, and the signal is read by a diamond sensor with NV centers in a carbon matrix — artificial defects that, like a compass needle, respond sensitively to magnetic fields. The sensor is placed in optical tweezers — a laser beam that holds cells in a stream of liquid without contact — and measures the deflection of the magnetic 'needle'. Even a single tagged cell generates a clear signal of 89 microtesla with noise of just 3.9 — as if a compass picks up the breath of a tiny magnet. Amazingly, the diamond sensor is so sensitive that it can detect the magnetic field of a single electron — no bulky equipment is needed. This 'magnetic eye' paves the way for diagnosing diseases right inside the body, tracking changes in real time.
🎯 Diamond NV centers are engineered defects: a nitrogen atom sitting next to a vacancy in the crystal. Their sensitivity can capture the magnetic field of a single electron from several nanometers away.
🎬 This precision brings us closer to sci-fi medical scanners — like the tricorder from Star Trek, which diagnoses diseases one cell at a time.