The chemical composition of cells at the molecular level determines their growth, differentiation, structure, and function. Probing this composition is powerful because it provides invaluable insight into chemical processes inside cells and in certain cases allows disease diagnosis based on molecular profiles. However, many techniques analyze fixed cells or lysates of bulk populations, in which information about dynamics and cellular heterogeneity is lost. Recently, nucleic-acid-based probes have emerged as a promising platform for the detection of a wide variety of intracellular analytes in live cells with single-cell resolution. Recent advances in this field are described and common strategies for probe design, types of targets that can be identified, current limitations, and future directions are discussed.

中文翻译：

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核酸结构作为活细胞的细胞内探针。

细胞在分子水平上的化学成分决定了它们的生长、分化、结构和功能。探测这种成分非常有用，因为它可以提供对细胞内部化学过程的宝贵见解，并且在某些情况下可以根据分子谱进行疾病诊断。然而，许多技术分析固定细胞或大量群体的裂解物，其中有关动态和细胞异质性的信息丢失。最近，基于核酸的探针已成为以单细胞分辨率检测活细胞中多种细胞内分析物的有前途的平台。描述了该领域的最新进展，并讨论了探针设计的常见策略、可识别的目标类型、当前的局限性和未来的方向。