二硫化钛纳米片材料用于光声成像指导下的肿瘤光热
治疗研究
二硫化钛纳米片材料用于光声成像指导下的肿瘤光热治疗 第一章
中文摘要
最近，有着不寻常物理化学性质的二维纳米材料在材料科学与工程领域被广泛的研究。石墨烯是一种由碳原子组成呈蜂巢晶格的二维层状材料，显示出特殊的电子，光学，热力学，和机械性能。作为一种石墨烯类似物，过渡族金属二维硫化物如MoS2, MoSe2, WS2, WSe2和Bi2Se3，都是由六边形的金属原子夹在两层硫族元素之间组成三明治结构。近些年这些过渡金属二维硫化物已经发展成为材料科学领域的明星材料，并在包括纳米医药在内的诸多领域有着潜在的应用。
二硫化钛是一种典型的过渡族金属二维硫化物材料，其在电子器件领域或作为一种储氢材料在最近被广泛研究。在此篇工作中，我们用自下而上的液相合成方法合成了二硫化钛纳米片，然后用聚乙二醇（PEG）修饰，在各种生理溶液中获得很好的稳定性，以及在体外没有明显的毒性。由于在近红外区有很强的吸收，TiS2-PEG能够被用作光声成像的造影剂。在对携带肿瘤的小鼠进行全身给药后发现材料能够在肿瘤部位实现很高的富集。然后我们将TiS2-PEG纳米片用于体内肿瘤光热治疗，在尾静脉注射纳米材料以及外加近红外激光照射的情况下能够实现肿瘤的完全消融。我们的工作表明，在经过良好的表面修饰后，TiS2纳米片能够作为一种新的光热制剂用于成像指导下的肿瘤治疗。
关键词：二硫化钛 光声成像 光热治疗
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第一章 二硫化钛纳米片材料用于光声成像指导下的肿瘤光热治疗
Two-Dimensional TiS2 Nanosheets for in vivo Photoacoustic Imaging and Photothermal Cancer Therapy
Abstract
Recently, two-dimensional (2D) nanomaterials with unusual physical and chemical properties have been extensively explored in materials science and engineering. Graphene, a 2D single layer of carbon atoms of honeycomb lattice structure, as a typical example, has shown exceptional electronic, optical, thermal, and mechanical properties. As the analogues of graphene, transition-metal dichalcogenides (TMDCs) such as MoS2, MoSe2, WS2, WSe2 and Bi2Se3, consisting of hexagonal layers of metal atoms sandwiched between two layers of chalcogen atoms, have also become a star in materials science in recent years, showing promising applications in many different areas including nanomedicine.
Titanium dichalcogenides (TiS2) is a typical class of TMDC materials and has also been studied recently in electronic devices or as a hydrogen-storage material. In this study, TiS2 nanosheets, are synthesized by a bottom-up solution-phase method and then modified with polyethylene glycol (PEG), obtaining TiS2-PEG with high stability in physiological solutions and no appreciable in vitro toxicity. Due to their high absorbance in the near-infrared (NIR) region, TiS2-PEG nanosheets could offer strong contrast in photoacoustic imaging, which uncovers the high tumor uptake and retention of those nanosheets after systemic administration into tumor-bearing mice. We further apply TiS2-PEG nanosheets for in vivo photothermal therapy, which is able to completely eradicate the tumors on mice upon intravenous injection of TiS2-PEG and the followed NIR laser irradiation. Our work indicates that TiS2 nanosheets with appropriate surface coating (e.g. PEGylation) would be promising new class of
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二硫化钛纳米片材料用于光声成像指导下的肿瘤光热治疗 第一章
photothermal agent for imaging-guided cancer therapy.
Keywords: TiS2 photoacoustic imaging photothermal therapy
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