Research on self-assembled deoxyribonucleic acid (DNA) nanostructures with different shapes, sizes, and functions has recently made rapid progress owing to its biocompatibility, programmability, and stability. Among these, triangular unit-based DNA nanostructures, which are typically multi-arm DNA tiles, have been widely applied because of their unique structural rigidity, spatial flexibility, and cell permeability. Triangular unit-based DNA nanostructures are folded from multiple single-stranded DNA using the principle of complementary base pairing. Its shape and size can be determined using pre-set scaffold strands, segmented base complementary regions, and sequence lengths. The resulting DNA nanostructures retain the desired sequence length to serve as binding sites for other molecules and obtain satisfactory results in molecular recognition, spatial orientation, and target acquisition. Therefore, extensive research on triangular unit-based DNA nanostructures has shown that they can be used as powerful tools in the biosensing field to improve specificity, sensitivity, and accuracy. Over the past few decades, various design strategies and assembly techniques have been established to improve the stability, complexity, functionality, and practical applications of triangular unit-based DNA nanostructures in biosensing. In this review, we introduce the structural design strategies and principles of typical triangular unit-based DNA nanostructures, including triangular, tetrahedral, star, and net-shaped DNA. We then summarize the functional properties of triangular unit-based DNA nanostructures and their applications in biosensing. Finally, we critically discuss the existing challenges and future trends.

中文翻译：

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基于自组装三角形单元的DNA纳米结构的构建策略、功能特性和生物传感应用的最新进展


近年来，具有不同形状、尺寸和功能的自组装脱氧核糖核酸（DNA）纳米结构的研究由于其生物相容性、可编程性和稳定性而取得了快速进展。其中，基于三角形单元的DNA纳米结构，通常是多臂DNA瓦片，由于其独特的结构刚性、空间灵活性和细胞渗透性而被广泛应用。基于三角形单元的 DNA 纳米结构是利用互补碱基配对原理由多个单链 DNA 折叠而成。其形状和大小可以使用预设的支架链、分段的碱基互补区域和序列长度来确定。所得的DNA纳米结构保留了所需的序列长度，可作为其他分子的结合位点，并在分子识别、空间定向和目标捕获方面获得满意的结果。因此，对基于三角形单元的DNA纳米结构的广泛研究表明，它们可以用作生物传感领域的强大工具，以提高特异性、灵敏度和准确性。在过去的几十年里，人们已经建立了各种设计策略和组装技术来提高基于三角形单元的DNA纳米结构在生物传感中的稳定性、复杂性、功能性和实际应用。在这篇综述中，我们介绍了典型的基于三角形单元的DNA纳米结构的结构设计策略和原理，包括三角形、四面体、星形和网状DNA。然后我们总结了基于三角形单元的 DNA 纳米结构的功能特性及其在生物传感中的应用。最后，我们批判性地讨论现有的挑战和未来的趋势。