title: Fluorescent pH Sensors for Broad-Range pH Measurement Based on a Single Fluorophore.
abstract: We constructed a series of novel optical sensors for determination of broad-range pH based on a single fluorophore and multi-ionophores with different pK(a) values. These optical sensors use photoinduced electron transfer (PET) as the signal transduction and follow the design concept of "fluorophore-spacer-receptor (ionophore)" which employs 4-amino-1,8-naphthalimide as the single fluorophore, ethyl moiety as the spacer, and a series of phenols and anilines as the receptors. Key to the successful development of this sensor system is that coupling the receptors with six different pK(a) values with a single fluorophore produces the correct optical properties. This rational design affords a series of optical pH sensors with unique fluorescence property and accurately tunable pH measurement ranging from 1 to 14 pH units. Because of covalent immobilization of the indicators, these sensors demonstrate excellent stability, adequate reversibility, and satisfactory dynamic range up to full pH ranges (pH 1-14).
authors.affiliation: †Department of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Qi
authors.affiliation: †Department of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, P.R. China.
authors.forename: Daying
authors.initials: D
authors.lastname: Liu
authors.affiliation: †Department of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, P.R. China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Liu
authors.affiliation: ‡Heowns Biochem Technologies LLC, 6 Lanyuan Road, Tianjin 300384, P.R. China.
authors.forename: Shiquan
authors.initials: S
authors.lastname: Guan
authors.affiliation: ‡Heowns Biochem Technologies LLC, 6 Lanyuan Road, Tianjin 300384, P.R. China.
authors.forename: Fengli
authors.initials: F
authors.lastname: Shi
authors.affiliation: ‡Heowns Biochem Technologies LLC, 6 Lanyuan Road, Tianjin 300384, P.R. China.
authors.forename: Hexi
authors.initials: H
authors.lastname: Chang
authors.affiliation: ‡Heowns Biochem Technologies LLC, 6 Lanyuan Road, Tianjin 300384, P.R. China.
authors.forename: Huarui
authors.initials: H
authors.lastname: He
authors.affiliation: †Department of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, P.R. China.
authors.forename: Guangming
authors.initials: G
authors.lastname: Yang
mesh_terms: D015057:1-Naphthylamine / Q000031:analogs & derivatives* / Q000737:chemistry; D004566:Electrodes; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007476:Ionophores / Q000737:chemistry*; D015394:Molecular Structure; D053644:Naphthalimides / Q000737:chemistry*; D015363:Quinolones / Q000737:chemistry*
chemical_list: D005456:Fluorescent Dyes; D007476:Ionophores; D053644:Naphthalimides; D015363:Quinolones; C086538:4-amino-1,8-naphthalimide; D015057:1-Naphthylamine