铬掺杂镓锗酸锌基近红外长余辉纳米粒子的尺寸和余辉特性调控及其应用

Since near-infrared light locating in the biological transparency window (650-950 nm) possesses less absorption, large penetration depth and low light damage through tissue, more studies are focused on the issues related to biological imaging, disease diagnosis and therapy by using near infrared super long persistent luminescent nanoparticles and they show potential applications in the fields of physiology and pathology. At present, it is essential to prepare super long persistent nanoparticles with uniform and small size and long afterglow time and to develop new applications, such as temperature detection and disease diagnosis and therapy. In this project, we try to prepare Cr3+-doped zinc gallogermanate based super long afterglow nanoparticles by a hydrothermal method in combination with the heat treatment. We try to tune the size and afterglow properties of Cr3+-doped zinc gallogermanate based super long persistent luminescent nanoparticles by controlling the doping concentration of rare earth or main-group ions and to obtain Cr3+-doped zinc gallogermanate based super long persistent luminescent nanoparticles with uniform and small size and super long afterglow time for biological imaging and temperature detection; We try to understand how the doping of rare earth or main-group ions influences the surroundings of the surface and interior Cr3+ ions and the afterglow properties of nanoparticels; Cr3+-doped zinc gallogermanate based near infrared super long persistent luminescent nanoparticles are used to develop new applications, such as temperature detection and disease diagnosis and therapy.

基于处于生物组织透过窗口范围（650-950 nm）的近红外光具有在活体生物组织中吸收少、穿透深度大且能有效地避免生物组织光损伤的优点，采用近红外超长余辉发光纳米粒子的技术手段，日益成为生物组织成像、疾病诊断和治疗的研究热点，使其在生理学和病理学的领域有着广泛的应用前景。针对目前迫切需要制备具有均匀小尺寸、超长余辉时间的近红外长余辉发光纳米粒子及探索其在温度探测和疾病诊断、治疗等领域新应用的实际需求，本项目拟采用水热结合热处理方法制备镓锗酸锌基超长余辉纳米粒子，利用稀土或部分主族离子等掺杂手段，实现铬掺杂镓锗酸锌基纳米粒子的粒子尺寸和红外长余辉特性的调控，获得具有均匀小尺寸、超长余辉时间的可应用于生物成像和温度探测的多功能铬掺杂镓锗酸锌基纳米材料；研究热处理条件及稀土离子和部分主族离子掺杂对分布在纳米粒子表面和内部的铬离子局域环境及余辉特性的影响和内在联系。

由于处于生物组织透过窗口范围（650-950 nm）的近红外光具有在活体生物组织中吸收少、穿透深度大且能有效地避免生物组织光损伤的优点，故采用近红外超长余辉发光纳米粒子的技术手段，日益成为生物组织成像、疾病诊断和治疗的研究热点，使其在生理学和病理学的领域有着广泛的应用前景。.本项目采用水热法结合真空热处理方法制备了镓锗酸锌（ZGGO:Cr）基超长余辉纳米粒子，利用稀土离子（Gd, Pr, Nd）或主族离子（Bi, Si, Sn, Ge）等掺杂手段，实现了铬掺杂镓锗酸锌基纳米粒子的粒子尺寸和近红外长余辉特性的调控，阐明了热处理条件及稀土离子和主族离子掺杂对分布在纳米粒子表面和内部的铬离子局域环境及余辉特性的影响，获得了具有无生物荧光背景成像和温度传感双功能的铬掺杂镓锗酸锌基纳米探针。.本项目取得的创新成果主要有如下两个。一是基于ZGGO:Cr3+长余辉发光纳米粒子设计了长余辉发光纳米温度计，在298-325 K的温度范围内，测量灵敏度达0.043-0.047 K-1，其相比于已报道的近红外上转换荧光纳米温度计提高了大约一个量级。实验结果表明，比率式长余辉发光纳米温度计可以同步实现实时原位生物成像及局域温度探测，对设计新型荧光纳米功能材料在精准医学中的应用有着重要的指导意义。二是将ZnPc光敏剂分子加载到包覆介孔二氧化硅ZGGO:Cr,Bi纳米粒子 (ZGGO:Cr,Bi@mSiO2-ZnPc)的表面，构建了自导光动力治疗纳米平台。活体实验发现，红光635 nm激发下，通过产生单线态氧分子，癌细胞生长的抑制因子可达到80%，表明近红外余辉发光诱导的自导光动力治疗在精准医学领域有潜在的应用前景。