title: A ratiometric fluorescence sensor with broad dynamic range based on two pH-sensitive fluorophores.
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.
authors.affiliation: College of Environmental Science and Engineering, State Key Laboratory for Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082, P. R. China. cgniu@hnu.cn
authors.forename: Cheng-Gang
authors.initials: CG
authors.lastname: Niu
authors.forename: Xiao-Qin
authors.initials: XQ
authors.lastname: Gui
authors.forename: Guang-Ming
authors.initials: GM
authors.lastname: Zeng
authors.forename: Xing-Zhong
authors.initials: XZ
authors.lastname: Yuan
mesh_terms: D015057:1-Naphthylamine / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000737:chemistry; D000578:Amidines / Q000138:chemical synthesis / Q000737:chemistry; D004566:Electrodes; D005336:Fiber Optic Technology; D005456:Fluorescent Dyes; D006863:Hydrogen-Ion Concentration; D010879:Piperazines / Q000138:chemical synthesis / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000295:instrumentation / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D000578:Amidines; D005456:Fluorescent Dyes; C513396:N-allyl-4-(4'-methyl-piperazinyl)-1,8-naphthalimide; D010879:Piperazines; D014874:Water Pollutants, Chemical; C034807:tetra-4-amidinophenoxypropane; D015057:1-Naphthylamine