Abstract Self-monitored photo-thermal therapy (PTT) still faces huge challenge in cancer treatment, which aims to realize the real-time temperature reading during the course of optical heating. Exploiting new-type photo-thermal therapeutic agent (PTA) with thermometric function is considered to be one of effective methods to fulfill self-monitored PTT. In this work, spindle-like zircon-tetragonal (z-t) phase BiVO4:Yb3+/Er3+ up-conversion (UC) nano-particles as self-monitored PTAs were prepared through the combination of co-precipitation and hydrothermal method. Under 980 nm laser diode excitation, real-time thermometry was accomplished by monitoring thermo-responsive emission intensity ratio of Er3+ (2H11/2/4S3/2 → 4I15/2) transitions. Meanwhile, the photo-thermal conversion effect associated with UC process was trigged via the non-radiative transition channels. Considering the balance between UC emission intensity and heat generation, the optimal sample composition was determined as BiVO4:20%Yb3+/3%Er3+. Their maximum absolute sensitivity (Sa) reached 0.0125 K-1 at 460 K as the thermometer and the ability of photo-thermal conversion up to 3.32 K cm2/W as PTAs. Their potential applications in controlled subcutaneous photo-thermal treatment were estimated through ex vivo experiments. Results provided a new choice for nano-materials to realize real-time temperature feedback in the single host material (z-t BiVO4) during the course of PTT.

中文翻译：

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Er3+/Yb3+ Co掺杂锆石-四方BiVO4的温度自监测光热纳米粒子

摘要 自监测光热疗法（PTT）在癌症治疗中仍面临巨大挑战，其目标是在光加热过程中实现实时温度读数。开发具有测温功能的新型光热治疗剂（PTA）被认为是实现自我监测PTT的有效方法之一。在这项工作中，通过共沉淀和水热法相结合的方法制备了纺锤形锆石-四方 (zt) 相 BiVO4:Yb3+/Er3+ 上转换 (UC) 纳米颗粒作为自监测 PTA。在 980 nm 激光二极管激发下，通过监测 Er3+ (2H11/2/4S3/2 → 4I15/2) 跃迁的热响应发射强度比来实现实时测温。同时，与 UC 过程相关的光热转换效应是通过非辐射跃迁通道触发的。考虑到 UC 发射强度和发热之间的平衡，最佳样品组成确定为 BiVO4:20%Yb3+/3%Er3+。它们的最大绝对灵敏度 (Sa) 在 460 K 作为温度计时达到 0.0125 K-1，作为 PTA 的光热转换能力高达 3.32 K cm2/W。通过离体实验评估了它们在受控皮下光热治疗中的潜在应用。结果为纳米材料在 PTT 过程中实现单一主体材料 (zt BiVO4) 中的实时温度反馈提供了新的选择。20%Yb3+/3%Er3+。它们的最大绝对灵敏度 (Sa) 在 460 K 作为温度计时达到 0.0125 K-1，作为 PTA 的光热转换能力高达 3.32 K cm2/W。通过离体实验评估了它们在受控皮下光热治疗中的潜在应用。结果为纳米材料在 PTT 过程中实现单一主体材料 (zt BiVO4) 中的实时温度反馈提供了新的选择。20%Yb3+/3%Er3+。它们的最大绝对灵敏度 (Sa) 在 460 K 作为温度计时达到 0.0125 K-1，作为 PTA 的光热转换能力高达 3.32 K cm2/W。通过离体实验评估了它们在受控皮下光热治疗中的潜在应用。结果为纳米材料在 PTT 过程中实现单一主体材料 (zt BiVO4) 中的实时温度反馈提供了新的选择。