title: A new rhodamine B-based lysosomal pH fluorescent indicator.
abstract: We designed and synthesized a new pH fluorescent probe, RCE, based on structural changes of rhodamine dye at different pH values. The probe exhibits high selectivity, high sensitivity and quick response to acidic pH, as well as low cytotoxicity, excellent photostability, reversibility and cell membrane permeability. Fluorescence intensity at 584 nm was increased more than 150-fold within pH range 7.51-3.53. This probe has pKa value 4.71, which is valuable for studying acidic organelles. Because of its long absorption and emission wavelengths, RCE can avoid associated cell damage. The probe can selectively stain lysosomes and monitor lysosomal pH changes in living cells.
authors.affiliation: Institute of Organic Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, PR China.
authors.forename: Hong-Shui
authors.initials: HS
authors.lastname: Lv
authors.forename: Shu-Ya
authors.initials: SY
authors.lastname: Huang
authors.forename: Bao-Xiang
authors.initials: BX
authors.lastname: Zhao
authors.forename: Jun-Ying
authors.initials: JY
authors.lastname: Miao
mesh_terms: D002463:Cell Membrane Permeability; D002470:Cell Survival / Q000187:drug effects; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D006367:HeLa Cells / Q000187:drug effects; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008247:Lysosomes / Q000187:drug effects / Q000502:physiology*; D018942:Macrolides / Q000494:pharmacology; D012235:Rhodamines / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D005456:Fluorescent Dyes; D018942:Macrolides; D012235:Rhodamines; C040929:bafilomycin A1; C029773:rhodamine B
keywords: Fluorescent probe; Intracellular pH; Living cells; Lysosomes; Rhodamine B