A new near-infrared persistent luminescence nanoparticle as a multifunctional nanoplatform for multimodal imaging and cancer therapy.

Multifunctional nanoplatforms with multimodal imaging and cancer therapy capabilities have attracted attention in biomedical applications. Near-infrared persistent luminescence nanoparticles (NPLNPs) were considered one of the most promising candidates for constructing multifunctional nanoplatforms due to the absence of in situ excitation and high signal-to-noise ratios (SNRs). Here, we report a novel NPLNP mSiO2@Gd3Ga5O12:Cr3+, Nd3+ (mSiO2@GGO) as multifunctional nanoplatforms for multimodal imaging and cancer therapy. These NPs exhibited a persistent luminescence (745 nm) of more than 3 h in the first near-infrared window (NIR-I) after UV excitation, which can realize high SNRs and long-term in vivo imaging. Moreover, these NPs showed excellent NIR luminescence (1067 nm) in the second near-infrared window (NIR-II) under 808 nm excitation, which is more suitable for deep tissue imaging due to the lower photon scattering and deeper tissue penetration of NIR-II luminescence. Furthermore, the host Gd3Ga5O12 with high Gd3+ concentration showed a high r1 value (10.70 mM-1 s-1) and was suitable for T1 MR imaging. The mesoporous silica nanoparticles (mSiO2) served as a framework to control the mSiO2@GGO particle morphology and provide low toxicity and drug loading capacity for cancer therapy.