pH-Responsive Fluorescence Enhancement in Graphene Oxide-Naphthalimide Nanoconjugates: A Fluorescence Turn-On Sensor for Acetylcholine.
pH-Responsive Fluorescence Enhancement in Graphene Oxide-Naphthalimide Nanoconjugates: A Fluorescence Turn-On Sensor for Acetylcholine.
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DOI：
10.1002/chem.201702198
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发表时间：
2017-08
期刊：
影响因子：
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通讯作者：
Sreejith Mangalath;Silja Abraham;Joshy Joseph
中科院分区：
文献类型：
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作者：
Sreejith Mangalath;Silja Abraham;Joshy Joseph
报道了一种基于氧化石墨烯-萘酰亚胺（GO-NI）纳米复合物的pH敏感荧光“开启”传感器，通过监测水溶液中乙酰胆碱酯酶（AChE）的酶活性来检测乙酰胆碱（ACh）。通过1-乙基-3-（3-二甲氨基丙基）碳二亚胺/N-羟基琥珀酰亚胺偶联策略将吡啶甲基取代的NI衍生物共价锚定在GO/还原GO表面，合成了这些纳米复合物，并对其形态和物理性质进行了详细研究。GO和NI发色团之间的π-π相互作用的协同效应以及有效的光诱导电子和能量转移过程是这些纳米缀合物的荧光强烈猝灭的原因，这些纳米缀合物在酸性pH条件下受到扰动，导致荧光发射的显著增强。该纳米缀合物被成功地用于有效地感测由乙酰胆碱酯酶的酶活性引起的pH变化，从而证明其作为乙酰胆碱在神经生理范围内的荧光开启传感器的实用性。
A pH-sensitive, fluorescence "turn-on" sensor based on a graphene oxide-naphthalimide (GO-NI) nanoconjugate for the detection of acetylcholine (ACh) by monitoring the enzymatic activity of acetylcholinesterase (AChE) in aqueous solution is reported. These nanoconjugates were synthesized by covalently anchoring picolyl-substituted NI derivatives on the GO/reduced GO surface through a 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide coupling strategy, and the morphological and photophysical properties were studied in detail. Synergistic effects of π-π interactions between GO and the NI chromophore, and efficient photoinduced electron- and energy-transfer processes, were responsible for the strong quenching of fluorescence of these nanoconjugates, which were perturbed under acidic pH conditions, leading to significant enhancement of fluorescence emission. This nanoconjugate was successfully employed for the efficient sensing of pH changes caused by the enzymatic activity of AChE, thereby demonstrating its utility as a fluorescence turn-on sensor for ACh in the neurophysiological range.