title: Efficient two-photon fluorescent probe with red emission for imaging of thiophenols in living cells and tissues.
abstract: Thiophenols, a class of highly toxic and pollutant compounds, are widely used in industrial production. Some aliphatic thiols play important roles in living organisms. Therefore, the development of efficient methods to discriminate thiophenols from aliphatic thiols is of great importance. Although several one-photon fluorescent probes have been reported for thiophenols, two-photon fluorescent probes are more favorable for biological imaging due to its low background fluorescence, deep penetration depth, and so on. In this work, a two-photon fluorescent probe for thiophenols, termed NpRb1, has been developed for the first time by employing 2,4-dinitrobenzene-sulfonate (DNBS) as a recognition unit (also a fluorescence quencher) and a naphthalene-BODIPY-based through-bond energy transfer (TBET) cassette as a fluorescent reporter. The TBET system consists of a D-π-A structured two-photon naphthalene fluorophore and a red-emitting BODIPY. It displayed highly energy transfer efficiency (93.5%), large pseudo-Stokes shifts upon one-photon excitation, and red fluorescence emission (λem = 586 nm), which is highly desirable for bioimaging applications. The probe exhibited a 163-fold thiophenol-triggered two-photon excited fluorescence enhancement at 586 nm. It showed a high selectivity and excellent sensitivity to thiophenols, with a detection limit of 4.9 nM. Moreover, it was successfully applied for practical detection of thiophenol in water samples with a good recovery, two-photon imaging of thiophenol in living cells, and tissues with tissue-imaging depths of 90-220 μm, demonstrating its practical application in environmental samples and biological systems.
authors.affiliation: Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha, China 410082.
authors.forename: Hong-Wen
authors.initials: HW
authors.lastname: Liu
authors.affiliation: Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha, China 410082.
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Zhang
authors.affiliation: Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha, China 410082.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha, China 410082.
authors.forename: Qian-Qian
authors.initials: QQ
authors.lastname: Wang
authors.affiliation: Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha, China 410082.
authors.forename: Xiao-Xiao
authors.initials: XX
authors.lastname: Hu
authors.affiliation: Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha, China 410082.
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
authors.affiliation: Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha, China 410082.
authors.forename: Weihong
authors.initials: W
authors.lastname: Tan
mesh_terms: D000818:Animals; D002470:Cell Survival; D003116:Color; D005456:Fluorescent Dyes / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D008099:Liver / Q000737:chemistry*; D051379:Mice; D008819:Mice, Nude; D015394:Molecular Structure; D010636:Phenols / Q000032:analysis*; D017785:Photons; D045483:Rivers / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013438:Sulfhydryl Compounds / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D005456:Fluorescent Dyes; D010636:Phenols; D013438:Sulfhydryl Compounds; D014874:Water Pollutants, Chemical; C042983:thiophenol