title: Efficient Two-Photon Fluorescence Nanoprobe for Turn-On Detection and Imaging of Ascorbic Acid in Living Cells and Tissues.
abstract: Ascorbic acid (AA) serves as a key coenzyme in many metabolic pathways, and its abnormal level is found to be associated with several diseases. Therefore, monitoring AA level in living systems is of great biomedical significance. In comparison with one-photon excited fluorescent probes, two-photon (TP) excited probes are more suitable for bioimaging, as they could afford higher imaging resolution with deeper imaging depth. Here, we report for the first time an efficient TP fluorescence probe for turn-on detection and imaging of AA in living cells and tissues. In this nanosystem, the negatively charged two-photon nanoparticles (TPNPs), which were prepared by modifying the silica nanoparticles with a two-photon dye, could adsorb cobalt oxyhydroxide (CoOOH) nanoflakes which carried positive charge by electrostatic force, leading to a remarkable decrease in their fluorescence intensity. However, the introduction of AA could induce the fluorescence recovery of the nanoprobe because it could reduce CoOOH into Co(2+) and result in the destruction of the CoOOH nanoflakes. The nanosystem exhibits a high sensitivity toward AA, with a LOD of 170 nM observed. It also shows high selectivity toward AA over common potential interfering species. The nanoprobe possessed both the advantages of TP imaging and excellent membrane-permeability and good biocompatibility of the silica nanoparticles and was successfully applied in TP-excited imaging of AA in living cells and tissues.
authors.affiliation: Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals,Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University , Xinxiang 453007, China.
authors.forename: Hong-Min
authors.initials: HM
authors.lastname: Meng
authors.affiliation: Molecular Sciences and Biomedicine Laboratory, State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha 410082, China.
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Zhang
authors.affiliation: Molecular Sciences and Biomedicine Laboratory, State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha 410082, China.
authors.forename: Chan
authors.initials: C
authors.lastname: Yang
authors.affiliation: Molecular Sciences and Biomedicine Laboratory, State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha 410082, China.
authors.forename: Hailan
authors.initials: H
authors.lastname: Kuai
authors.affiliation: Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals,Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University , Xinxiang 453007, China.
authors.forename: Guo-Jiang
authors.initials: GJ
authors.lastname: Mao
authors.affiliation: Molecular Sciences and Biomedicine Laboratory, State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha 410082, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Gong
authors.affiliation: Molecular Sciences and Biomedicine Laboratory, State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University , Changsha 410082, China.
authors.forename: Wenhan
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals,Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University , Xinxiang 453007, China.
authors.forename: Suling
authors.initials: S
authors.lastname: Feng
authors.affiliation: Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals,Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, School of Chemistry and Chemical Engineering, Henan Normal University , Xinxiang 453007, China.
authors.forename: Junbiao
authors.initials: J
authors.lastname: Chang
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000032:analysis*; D002470:Cell Survival; D003035:Cobalt / Q000737:chemistry*; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D008099:Liver / Q000737:chemistry*; D008856:Microscopy, Fluorescence; D015394:Molecular Structure; D053758:Nanoparticles / Q000737:chemistry*; D010087:Oxides / Q000138:chemical synthesis / Q000737:chemistry*; D010316:Particle Size; D017785:Photons; D051381:Rats; D013499:Surface Properties
chemical_list: D005456:Fluorescent Dyes; D010087:Oxides; C477250:HCoO2; D003035:Cobalt; D001205:Ascorbic Acid