Detection of Mercury Ion by Infrared Fluorescent Protein and Its Hydrogel-Based Paper Assay
Detection of Mercury Ion by Infrared Fluorescent Protein and Its Hydrogel-Based Paper Assay
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DOI：
10.1021/ac103236g
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发表时间：
2011-03-15
影响因子：
7.4
通讯作者：
Tang, Yi
中科院分区：
文献类型：
--
作者：
Gu, Zhen;Zhao, Muxun;Tang, Yi
汞是一种高度危险和广泛的污染物，具有生物累积特性。满足所需选择性、高灵敏度、良好生物相容性和自然环境中低背景干扰标准的新方法正在不断探索中。本文描述了一种新的策略，利用红外荧光蛋白（IFP）及其发色团的组合作为红外荧光探针汞离子（Hg（II））检测。汞（II）已被证实对IFP的半胱氨酸残基（C24）具有特异性结合亲和力，从而抑制IFP发色团胆绿素（By）与C24的结合，并“关闭”IFP的红外发射。IFP/BV传感器在较宽的pH范围内对其他金属离子中的Hg（II）具有高选择性。体外检测限确定为小于50 nM。作为一种基因编码的探针，我们证明IFP/BV传感器可以作为一种工具来检测汞（II）在活的生物体或组织。此外，我们已经开发了一种蛋白质-琼脂糖水凝胶为基础的纸上检测，以检测汞（II）在一个便携式和强大的方式来检测IFP。
Mercury is a highly hazardous and widespread pollutant with bioaccumulative properties. Novel approaches that meet the criteria of desired selectivity, high sensitivity, good biocompatibility, and low background interference in natural settings are continuously being explored. We herein describe a new strategy utilizing the combination of infrared fluorescent protein (IFP) and its chromophore as an infrared fluorescence probe for mercury ion (Hg(II)) detection. Hg(II) has been validated to have specific binding affinity to a cysteine residue (C24) of IFP, thereby inhibiting the conjugation of IFP chromophore biliverdin (By) to C24 and "turning off" the infrared emission of IFP. The IFP/BV sensor has high selectivity toward Hg(II) among other metal ions over a broad pH range. The in vitro detection limit was determined to be less than 50 nM. As a genetically encoded probe, we demonstrate the IFP/BV sensor can serve as a tool to detect Hg(II) in living organisms or tissues. Moreover, we have exploited a protein-agarose hydrogel-based paper assay to immobilize IFP for detection of Hg(II) in a portable and robust fashion.