Near-Infrared Light-Excited Upconverting Persistent Nanophosphors in Vivo for Imaging-Guided Cell Therapy

Optical imaging for biological applications is in need of more sensitive tool. Persistent luminescent nanophosphors enable highly sensitive in vivo optical detection and almost completely avoid tissue autofluorescence. Nevertheless, the actual persistent luminescent nanophosphors necessitate ex vivo activation before systemic operation, which severely restricted the use of long-term imaging in vivo. Hence, we introduced a novel generation of optical nanophosphors, based on (Zn₂SiO₄:Mn):Y³⁺, Yb³⁺, Tm³⁺ upconverting persistent luminescent nanophosphors; these nanophosphors can be excited in vivo through living tissues by highly penetrating near-infrared light. We can trace labeled tumor therapeutic macrophages in vivo after endocytosing these nanophosphors in vitro and follow macrophages biodistribution by a simple whole animal optical detection. These nanophosphors will open novel potentials for cell therapy research and for a variety of applications in diagnosis in vivo

Near-Infrared Light Triggered Upconversion Optogenetic Nanosystem for Cancer Therapy

<i>In vivo</i> the application of optogenetic manipulation in deep tissue is seriously obstructed by the limited penetration depth of visible light that is continually applied to activate a photoactuator. Herein, we designed a versatile upconversion optogenetic nanosystem based on a blue-light-mediated heterodimerization module and rare-earth upconversion nanoparticles (UCNs). The UCNs worked as a nanotransducer to convert external deep-tissue-penetrating near-infrared (NIR) light to local blue light to noninvasively activate photoreceptors for optogenetic manipulation <i>in vivo</i>. In this, we demonstrated that deeply penetrating NIR light could be used to control the apoptotic signaling pathway of cancer cells in both mammalian cells and mice by UCNs. We believe that this interesting NIR-light-responsive upconversion optogenetic nanotechnology has significant application potentials for both basic research and clinical applications <i>in vivo</i>