Nanowerk

Diamond Quantum Sensors Detect Immune Cell Inflammation Through Electric Charge Shifts

Researchers at the University of Chicago and the University of Iowa have demonstrated that diamond nanoprobes containing nitrogen‑vacancy (NV) centers can detect inflammation in individual macrophages by measuring electric‑field‑induced shifts in the zero‑field splitting (ZFS) parameter. By introducing a secondary transverse dipole term (d′) into the NV Hamiltonian, the team overcame the orientation‑averaging problem that previously masked electric‑field signals, converting surface‑charge interactions into a reliable read‑out. Experiments showed bare nanodiamonds exhibit a −0.45 MHz ZFS drift in physiological buffer, while silica‑coated core‑shell particles remain stable, confirming the charge‑transfer mechanism. The method provides label‑free, real‑time monitoring of single‑cell immune activity, with potential extensions to T‑cell cytotoxicity assays.