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PubMed · 16222379

A ratiometric fluorescence sensor with broad dynamic range based on two pH-sensitive fluorophores.

Cheng-Gang Niu·Xiao-Qin Gui·Guang-Ming Zeng·Xing-Zhong Yuan
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Abstract

This paper describes a novel ratiometric fluorescence sensor for pH measurement. Two pH-sensitive fluorophores, N-allyl-4-(4'-methyl-piperazinyl)-1,8-naphthalimide (AMPN) and meso-5,10,15,20-tetra-(4-allyloxyphenyl)porphyrin (TAPP), which served as referencing indicators for each other, were co-polymerized with acrylamide, hydroxyethyl methacrylate and triethylene glycol dimethacrylate on the silanized glass surface. The proposed sensor is based on the pH-dependent fluorescence intensities of the two fluorophores in different pH ranges. The sensor covers a broad dynamic range of pH 1.5-9.0. It exhibits satisfactory analytical performance in terms of selectivity, reproducibility and stability. The successful fabrication of the proposed sensor provides an alternative concept to utilizing two or more fluorophores for the development of ratiometric sensors covering a broad range of pH.

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1-NaphthylamineAmidinesElectrodesFiber Optic TechnologyFluorescent DyesHydrogen-Ion ConcentrationPiperazinesSpectrometry, FluorescenceWater Pollutants, ChemicalEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Cheng-Gang Niu, Xiao-Qin Gui, Guang-Ming Zeng, Xing-Zhong Yuan. 2005-10-03. A ratiometric fluorescence sensor with broad dynamic range based on two pH-sensitive fluorophores.. https://doi.org/10.1039/b504882f

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