Photoacoustic technology in combination with molecular imaging is a highly effective method for accurately diagnosing brain glioma. For glioma detection at a deeper site, contrast agents with higher photoacoustic imaging sensitivity are needed. Herein, we report a MoS₂–ICG hybrid with indocyanine green (ICG) conjugated to the surface of MoS₂ nanosheets. The hybrid significantly enhanced photoacoustic imaging sensitivity compared to MoS₂ nanosheets. This conjugation results in remarkably high optical absorbance across a broad near-infrared spectrum, redshifting of the ICG absorption peak and photothermal/photoacoustic conversion efficiency enhancement of ICG. A tumor mass of 3.5 mm beneath the mouse scalp was clearly visualized by using MoS₂–ICG as a contrast agent for the in vivo photoacoustic imaging of orthotopic glioma, which is nearly twofold deeper than the tumors imaged in our previous report using MoS₂ nanosheet. Thus, combined with its good stability and high biocompatibility, the MoS₂–ICG hybrid developed in this study has a great potential for high-efficiency tumor molecular imaging in translational medicine.

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光声技术与分子成像相结合是一种准确诊断脑神经胶质瘤的高效方法。为了在更深的部位检测神经胶质瘤，需要具有更高的光声成像灵敏度的造影剂。在本文中，我们报道了一种MoS ₂ -ICG杂化体，其中吲哚菁绿（ICG）与MoS ₂纳米片的表面共轭。与MoS ₂纳米片相比，该杂化物显着增强了光声成像灵敏度。这种共轭导致在宽广的近红外光谱范围内具有极高的光吸收率，ICG吸收峰发生红移，并提高了ICG的光热/光声转换效率。通过使用MoS _2可以清晰地观察到小鼠头皮下方3.5毫米的肿瘤块–ICG作为原位神经胶质瘤体内光声成像的造影剂，其深度比我们先前使用MoS ₂纳米片报道的肿瘤深两倍。因此，结合其良好的稳定性和高生物相容性，本研究开发的MoS ₂ -ICG杂化物在转化医学中具有高效肿瘤分子成像的巨大潜力。

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