The application of gold nanoparticles in the biomedical field has been widely explored in the last decades owing to their high biocompatibility, easy functionalization, and their structurally highly dependent optical properties. Among the different types of gold-based nanostructures, gold nanoshells (GNSs) are a particularly interesting option due to their complex dual structure, which allows the integration of several functionalities and a wide tunability of their optical response. Despite the remarkable progress made for the design of GNSs with the optimal characteristics for the intended application, the development of nanosystems that display the desired functionalities and preserve them in biological environments while showing effective targeting capability is still a challenge. In this review, the different synthetic routes proposed for the design of GNSs, their most remarkable optical properties, and the most relevant concerns associated with their interaction with biological systems are discussed. The application of these nanostructures for different diagnostic and/or therapeutic purposes is also reviewed. Finally, major remaining barriers to the clinical translation of GNSs and potential future directions of research in this field are critically commented.

中文翻译：

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重新审视金纳米壳作为多功能生物医学纳米工具


金纳米颗粒因其高生物相容性、易功能化以及结构高度依赖性的光学特性，在过去几十年中得到了广泛的探索。在不同类型的金基纳米结构中，金纳米壳 （GNS） 是一个特别有趣的选择，因为它们具有复杂的双重结构，允许集成多种功能并对其光学响应进行广泛的可调性。尽管在设计具有预期应用最佳特性的 GNS 方面取得了显着进展，但开发显示所需功能并将其保存在生物环境中同时显示有效靶向能力的纳米系统仍然是一个挑战。在这篇综述中，讨论了为 GNS 设计提出的不同合成路线、它们最显着的光学特性以及与它们与生物系统相互作用相关的最相关问题。还回顾了这些纳米结构在不同诊断和/或治疗目的中的应用。最后，批判性地评论了 GNS 临床转化仍然存在的主要障碍以及该领域潜在的未来研究方向。