Abstract Cancer could seriously threaten people's health, even life. Rare earth upconversion nanoparticles (UCNPs) that emit higher energy UV/visible light when excited by low energy NIR light have aroused considerable attention in biomedical fields, which stems from their unique optical and chemical properties including the low spontaneous fluorescence, high signal-to-noise ratio, tunable emission, low toxicity and high penetration depth properties. NIR light can effectively stimulate the photoinduced reaction through UV/visible emissions from RE3+ UCNPs. This review article mainly summarizes the recent progress of RE3+ based stimuli-responsive nanocompounds for drug delivery in biomedical research, along with the various functional modification methods. Under special stimuli-responsive conditions, such as pH, temperature, light and redox gradients, the drugs can be transferred and released controllably. The traceable targeted drug delivery manner can boost drug efficacy in tumor therapy, while minimizing the side effects of cytotoxic drugs. Finally, the future developments and challenges for upconversion materials are discussed.

中文翻译：

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上转换稀土荧光纳米粒子在生物医学给药系统中的应用

摘要 癌症严重威胁着人们的健康，甚至生命。稀土上转换纳米粒子 (UCNPs) 在被低能近红外光激发时会发出更高能量的紫外/可见光，在生物医学领域引起了相当大的关注，这源于其独特的光学和化学性质，包括低自发荧光、高信号转噪声比、可调发射、低毒性和高穿透深度特性。NIR 光可以通过 RE3+ UCNPs 的紫外/可见光发射有效地刺激光诱导反应。这篇综述文章主要总结了基于RE3+的刺激响应纳米化合物在生物医学研究中用于药物递送的最新进展，以及各种功能修饰方法。在特殊的刺激响应条件下，如 pH、温度、光和氧化还原梯度，药物可以可控地转移和释放。可追溯的靶向给药方式可以提高肿瘤治疗中的药物疗效，同时最大限度地减少细胞毒性药物的副作用。最后，讨论了上转换材料的未来发展和挑战。