Kong Jia, Zhao Shixuan, Han Xue, Li Wenxin, Zhang Jiaxing, Wang Yuefei, Shen Xihui, Xia Yinqiang, Li Zhonghong
College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi 712100, P. R. China.
State Key Laboratory of Chemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, P. R. China.
Anal Chem. 2023 Mar 21;95(11):5053-5060. doi: 10.1021/acs.analchem.2c05609. Epub 2023 Mar 9.
Fluorescent proteins (FPs) provide a ratiometric readout for quantitative assessment of the destination of internalized biomolecules. FP-inspired peptide nanostructures that can compete with FPs in their capacity are the most preferred building blocks for the synthesis of fluorescent soft matter. However, realizing a ratiometric emission from a single peptide fluorophore remains exclusive since multicolor emission is a rare property in peptide nanostructures. Here, we describe a bioinspired peptidyl platform for ratiometric intracellular quantitation by employing a single ferrocene-modified histidine dipeptide. The intensiometric ratio of green to blue fluorescence correlates linearly with the concentration of the peptide by three orders of magnitude. The ratiometric fluorescence of the peptide is an assembly-induced emission originating from hydrogen bonds and aromatic interactions. Additionally, modular design enables ferrocene-modified histidine dipeptides to use as a general platform for the construction of intricate peptides that retain the ratiometric fluorescent properties. The ratiometric peptide technique promises flexibility in the design of a wide spectrum of stoichiometric biosensors for quantitatively understanding the trafficking and subcellular fate of biomolecules.
荧光蛋白（FPs）为内化生物分子的目的地定量评估提供了一种比率读出方式。能够在功能上与荧光蛋白相媲美的受荧光蛋白启发的肽纳米结构，是合成荧光软物质的最理想构建模块。然而，由于多色发射在肽纳米结构中是一种罕见特性，实现单个肽荧光团的比率发射仍然是独一无二的。在此，我们描述了一种通过使用单个二茂铁修饰的组氨酸二肽进行比率细胞内定量的仿生肽基平台。绿色荧光与蓝色荧光的强度比率与肽浓度在三个数量级上呈线性相关。该肽的比率荧光是一种源自氢键和芳香相互作用的聚集诱导发射。此外，模块化设计使二茂铁修饰的组氨酸二肽能够用作构建保留比率荧光特性的复杂肽的通用平台。比率肽技术有望为设计各种化学计量生物传感器提供灵活性，以便定量了解生物分子的运输和亚细胞命运。
