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恶性肿瘤的早期检测在降低死亡率方面发挥着关键作用.双模态生物医学成像策略能够为癌症的精确诊断提供更多的可用信息,成为当前研究热点.该文通过简便的一锅水热法制备了高度生物相容的多功能纳米粒子(CuSSe NPs),可以特异性响应肿瘤部位过量的过氧化氢(H2O2),实现Cu(Ⅰ)向Cu(Ⅱ)的转化,可作为原位自生磁共振成像(MRI)造影剂用于肿瘤诊断.此外,由于近红外(NIR)区域的强吸收,CuSSe NPs表现出良好的光热转换性能,可作为体内实时癌症监测的光热成像剂.血液分析结果表明CuSSe NPs具有较好的生物相容性,无急性、长期毒性.该纳米材料已被证明是一种潜在的纳米探针,可用于临床癌症治疗中具有高肿瘤对比度的双模态成像.“,”Early accurate detection of malignancy tumor plays a key role in reducing cancer mortality. Current detection strategies mainly rely on the imaging technologies.However,single-modality biomedical image cannot provide enough information due to its inherent defects.Therefore,the dual-modal biomedical imaging strategies which can provide more available information for precise cancer diagnosing,have become a hotspot for research. Among the biomedical imaging methods applied in clinical, magnetic resonance imaging(MRI)is considered to be an effective method for clinicopathological diagnosis due to its high three-dimensional(3D)spatial resolution and high soft tissue resolution,but it has also been plagued by the long inspection time and expensive inspection fee. Whereas, thermal imaging is an efficient and minimally invasive method for biomedical imaging, which could offset the above deficiencies of MRI. Most importantly, it is convenient and economical. Furthermore, the development of multifunctional nanoparticles brings more possibilities for the establishment of novel tumor diagnostic platforms, which is expected to have a greater impact in the field of biomedical imaging. Thus, a kind of highly biocompatible multifunctional nanoparticles(CuSSe NPs) were prepared by a facile one-pot hydrothermal method for tumor MRI/thermal imaging in this study.The diameter of CuSSe NPs is about 100 nm, and it exhibited an excellent dispersity in aqueous solution.However,the CuSSe NPs did not exhibited the best MRI capability due to the existence of diamagnetic Cu(Ⅰ),but in vivo experiments demonstrated that the CuSSe NPs could specifically respond to the excess hydrogen peroxide(H2O2) at the tumor site so as to realize the conversion of diamagnetic Cu(Ⅰ) to paramagnetic Cu(Ⅱ), acting as in situ autogenous MRI agents for visualizing and diagnosing the location of cancer.Moreover,attributing to the intensive absorption in the second near-infrared(NIR-Ⅱ)region, CuSSe NPs exhibited as a concentration-and laser-power-dependent photothermal imaging agent with considerable photothermal conversion effects in the NIR-Ⅱ region. The photothermal conversion efficiency of CuSSe NPs was calculated to be-48％ under the illumination of NIR-Ⅱ laser (1064 nm). Both in vivo and in vivo experiments demonstrated that CuSSe NPs have good thermal imaging capabilities for real-time cancer monitoring. Furthermore, the blood analysis on the mice injected with or without CuSSe NPs were evaluated after 3 and 25 days. The results showed that CuSSe NPs were highly biocompatible without acute and long-term toxicity.Consequently,the constructed copper-based multifunctional NPs have been demonstrated to be a potential nanoprobe for dual-modal imaging with high tumor contrast in clinical cancer theranostics.