title: Sensitive detection of strong acidic condition by a novel rhodamine-based fluorescent pH chemosensor.
abstract: A novel rhodamine-based fluorescent pH probe responding to extremely low pH values has been synthesized and characterized. This probe showed an excellent photophysical response to pH on the basis that the colorless spirocyclic structure under basic conditions opened to a colored and highly fluorescent form under extreme acidity. The quantitative relationship between fluorescence intensity and pH value (1.75-2.62) was consistent with the equilibrium equation pH = pKa + log[(Imax - I)/(I - Imin)]. This sensitive pH probe was also characterized with good reversibility and no interaction with interfering metal ions, and was successfully applied to image Escherichia coli under strong acidity.
authors.affiliation: College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Jia-Lian
authors.initials: JL
authors.lastname: Tan
authors.affiliation: College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Yang
authors.affiliation: College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Zhang
authors.affiliation: College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Shu-Jin
authors.initials: SJ
authors.lastname: Cheng
authors.affiliation: College of Pharmaceutical Sciences, Southwest University, Chongqing, 400715, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Zuo
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, 400715, China.
authors.forename: Huawei
authors.initials: H
authors.lastname: He
mesh_terms: D000143:Acids / Q000032:analysis*; D004926:Escherichia coli / Q000737:chemistry; D005456:Fluorescent Dyes / Q000032:analysis / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D012235:Rhodamines / Q000032:analysis / Q000737:chemistry*; D013053:Spectrophotometry
chemical_list: D000143:Acids; D005456:Fluorescent Dyes; D012235:Rhodamines
keywords: E. coli; extreme acidity; pH; rhodamine-derived probe