X-ray excited Mn2+-doped persistent luminescence materials with biological window emission for in vivo bioimaging

Abstract

In recent years, persistent luminescence materials (PLMs) excited by X-rays and emitting in biological windows have received extensive attention in the field of high-sensitivity bioimaging. Transition metal Mn2+ is an ideal emission center, but few studies focus on Mn2+-doped PLMs with X-ray excitation and biological window emission. Here, we report a Mn2+-doped PLM, LiYGeO4:Mn2+ (LYGM), with excellent biological window persistent luminescence emission. After excitation by UV, LYGM produces a durable biological window of persistent luminescence emission at 660 nm for up to 20 h. More importantly, LYGM can be repeatedly excited by X-rays, resulting in long-term biological window persistent luminescence emission. In addition, we obtain LYGM around 200 nm in diameter by ball milling and centrifugation and improve its biocompatibility by surface modification to apply it to in vivo imaging in mice. After LYGM are injected into mice through the tail vein, in situ excitation of X-rays can be achieved. After the persistent luminescence decays, LYGM can be re-excited for repeated imaging. Therefore, LYGM shows potential prospects for in vivo deep tissue and long-term bioimaging.