基于稀土纳米荧光探针的唾液肿瘤标志物体外检测

Rare-earth (RE) doped luminescent nanoparticles (NPs), emerging as a new-generation luminescent bioprobes and as an alternative to conventional molecular probes, show great potentials for their biomedical applications in early cancer detection and targeted bioimaging. In this project, we are devoted to the investigation of novel nano-bioprobes based on RE-doped luminescent NPs for the biodetection of human tumor markers and tumor-targeted bioimaging. We aim to establish the measurement method for the evaluation of the absolute upconverting (UC)/downshifting luminescence quantum yield in RE-doped NPs, propose reliable and universal bioconjugation techniques for specific binding of tumor markers, and develop the general protocols for both heterogeneous time-resolved (TR)/UC luminescence and homogeneous TR-FRET/UC-FRET in-vitro detection of serum/saliva tumor markers such as carcino-embryonic antigen (CEA) as well as CEA-targeted bioimaging. Particularly, it is expected that the detection limit of CEA for human saliva samples finally reaches as low as 0.2 fM, which fulfills the requirement of clinical assays. We anticipate that, the developed RE-doped nano-bioprobes will show much more excellent features in the luminescence efficiency, photochemical stability, and biodetection/bioimaging sensitivity than traditional molecular bioprobes, and thus may play crucial roles in the fields of early cancer detection, point-of-care test, and community and family theranostics. The development of RE-doped luminescent nano-bioprobes will lead to the breakthrough for the use of RE luminescent materials in biomedical applications and achieve the high-value utilization of RE resources as well as the extension of RE industrial chain.

稀土纳米发光材料是目前普遍看好的新一代荧光标记材料，有望替代分子探针在癌症早期诊疗和靶向示踪等生物医学领域发挥重要作用。本项目致力于研发可用于人体肿瘤标志物检测和靶向生物成像的新型高效稀土纳米荧光探针，建立评价和提高稀土上/下转换发光材料发光效率的方法，发展成熟可靠的具有肿瘤标志物特异性识别作用的生物偶联技术，开发基于新型稀土纳米荧光探针的时间分辨/上转换荧光异相检测和共振能量传递均相体外检测技术，实现对人体血清和唾液中肿瘤标志物的高灵敏特异性体外检测及肿瘤靶向示踪，其中对唾液中癌胚抗原的检测限低于0.2 fM，达到临床检测要求。预期本项目研制的纳米探针在发光效率、光稳定性和检测限等方面都表现出优于传统分子探针的良好性能，在癌症早期检测、即时检验、社区医疗和家庭诊断等领域发挥重要作用。稀土纳米探针的开发有望加快实现稀土发光材料在生物医学应用的突破，促进稀土资源高值利用和产业链延伸。

本项目主要开展了稀土纳米荧光材料的控制合成、光学性能和及其应用研究。对材料的电子结构、表面修饰、结构表征及其发光物理进行了全面的分析，筛选出了几种高效且高灵敏度的纳米荧光标记材料，并实现了对一系列人体唾液和血清肿瘤标志物的高灵敏检测。本项目研制的稀土纳米荧光标记材料在荧光强度、光稳定性、生物亲和性和灵敏度等方面都表现出优于有机染料和稀土鳌合物的良好性能，在生物成像、免疫分析、和生物分子相互作用追踪等领域将发挥重要的应用。本项目执行期间，在Nano Today、 Coord. Chem. Rev.、 Nat. Commun.、 Angew. Chem. Int. Ed.等专业期刊发表了高影响力SCI论文39篇，其中影响因子>14一区论文15篇，获授权中国发明专利9项。