Herein, a multifunctional dual-modal imaging probe is successfully developed to integrate the advantages of second near-infrared window (NIR-II, 1000-1700 nm) fluorescence imaging (FI) and photoacoustic imaging (PAI) with the ultimate goal of improving diseases diagnosis and management. Melanin-inspired polydopamine (PDA) polymer coated NaYF4:Yb3+,Er3+@NaYbF4@NaYF4:Nd3+ down conversion nanoparticles (DCNPs) is designed via water-in-oil microemulsion method, which comprises a DCNP core, acting as the NIR-II optical imaging agent, and a PDA shell, acting as the PA contrast agent. By taking the advantages of high spatial resolution and excellent temporal resolution, the dual-modal contrast agent is capable for high sensitivity real-time visualization of gastrointestinal tract, diagnosis of gastrointestinal peristalsis disorder and NIR-II FI-guided intestinal obstruction surgery. All of the above results demonstrate the great potential of DCNP@PDA NP as an efficient NIR-II/PAI dual-modal contrast agent for precision medicine.

中文翻译：

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聚多巴胺包被的下转换纳米粒子作为一种有效的双模近红外-II 荧光和光声造影剂，用于体内胃肠道的无创可视化。

在此，成功开发出多功能双模态成像探头，融合第二近红外窗口（NIR-II，1000-1700 nm）荧光成像（FI）和光声成像（PAI）的优点，最终目标是改善疾病诊断和管理。采用油包水微乳液法设计了黑色素启发的聚多巴胺（PDA）聚合物包覆的NaYF4:Yb3+,Er3+@NaYbF4@NaYF4:Nd3+下转换纳米粒子（DCNP），其包含DCNP核，充当NIR-II光学器件显像剂和 PDA 外壳，充当 PA 造影剂。双模态造影剂利用高空间分辨率和优异的时间分辨率的优点，能够进行胃肠道高灵敏度实时可视化、胃肠蠕动障碍的诊断以及NIR-II FI引导的肠梗阻手术。上述所有结果都证明了DCNP@PDA NP作为一种高效的NIR-II/PAI双模态造影剂在精准医疗中的巨大潜力。