Single-molecule fluorescence resonance energy transfer (smFRET) requires significant spectral overlap between the donor emission and the acceptor absorption, and its efficiency is strongly dependent on the donor-acceptor distance. Consequently, smFRET has the capability to study molecular interactions of biomolecules with sub-nanometer resolution in a homogeneous manner without the involvement of any separation steps. The smFRET has significant advantages of high signal-to-noise ratio, low sample consumption, and homogeneous assay, providing a new approach to detect low-abundant biomolecules with extremely high sensitivity. In this review, we summarize the strategies for improving smFRET efficiency and the applications of smFRET in sensitive detection of DNAs, microRNAs, enzymes, and in situ imaging of single-nucleotide mutation. Moreover, we provide new insight into the challenges and future perspectives of smFRET.

单分子荧光共振能量转移（smFRET）需要在供体发射和受体吸收之间存在明显的光谱重叠，并且其效率在很大程度上取决于供体-受体距离。因此，smFRET能够以均一的方式研究具有亚纳米分辨率的生物分子的分子相互作用，而无需任何分离步骤。smFRET具有高信噪比，低样品消耗和均相测定的显着优势，提供了一种以极高的灵敏度检测低丰度生物分子的新方法。在这篇综述中，我们总结了提高smFRET效率的策略以及smFRET在DNA，microRNA，酶的敏感检测以及单核苷酸突变的原位成像中的应用。而且，