Native point defect modulated Cr 3+ -LaAlO 3 as an in vitro excited contrast medium for in vivo near-infrared persistent deep-tissue bio-imaging.

Due to the synergistic effect of Cr ³⁺ dopant levels and defect state, the luminescence intensity and decay time in LaAlO ₃ are remarkably enhanced, and the emission wavelength from deep-red (Cr ³⁺ as the luminescent center) to NIR-II/III (defect states as the luminescent center) can be effectively tuned via an energy transfer process.