title: Highly Specific and Ultrasensitive Two-Photon Fluorescence Imaging of Native HOCl in Lysosomes and Tissues Based on Thiocarbamate Derivatives.
abstract: Hypochlorous acid (HOCl) acts as a weak acid distributed mainly in acidic organelle lysosomes of phagocytes and plays a crucial role in the immune defense. The elaborate interrelation between the variations of HOCl levels in lysosomes and different physiological and pathological processes remains unclear. Thus, the accurate determination of lysosomal HOCl in living cells and in vivo is very important. Because of extremely low concentration and difficulty in distinguishing HOCl from OCl-under the physiological environment, it is still a great challenge to specifically monitor the intracellular intrinsic HOCl levels without exogenous stimulation, which impedes an exact understanding of its biological roles. In this paper, based on the electrophilic addition of Cl+to sulfide moiety, we have developed a two-photon fluorescent probe O-(N-butyl-1,8-naphthalimide)-4-yl-N,N-dimethylthiocarbamate (NDMTC) for the specific determination of HOCl over OCl-and other bioactive molecules. Our results show that NDMTC possesses a detection limit of 7.6 pM, and it is the first fluorescent probe for detecting HOCl at the picomolar level. Furthermore, by introducing an alkylmorpholine group to the NDMTC framework, the lysosome-targetable derivative Lyso-NDMTC was obtained, and its ability to image HOCl in the lysosome organelles was clearly confirmed. Combined with two-photon fluorescence imaging of background suppression and deeper tissue penetration, NDMTC and Lyso-NDMTC were used to successfully visualize intracellular native HOCl and discern tumor tissue in mice. This study offers two perfect fluorescence imaging probes for further investigation of pathological roles of HOCl in various diseases.
authors.affiliation: College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals, Institute of Biomedical Sciences, Shandong Normal University , Jinan 250014, People's Republic of China.|School of Resources and Environment, University of Jinan , Shandong Provincial Engineering Technology Research Center for Ecological Carbon Sink and Capture Utilization, Jinan 250022, People's Republic of China.
authors.forename: Baocun
authors.initials: B
authors.lastname: Zhu
authors.affiliation: College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals, Institute of Biomedical Sciences, Shandong Normal University , Jinan 250014, People's Republic of China.
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.affiliation: School of Resources and Environment, University of Jinan , Shandong Provincial Engineering Technology Research Center for Ecological Carbon Sink and Capture Utilization, Jinan 250022, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Shu
authors.affiliation: College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals, Institute of Biomedical Sciences, Shandong Normal University , Jinan 250014, People's Republic of China.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Resources and Environment, University of Jinan , Shandong Provincial Engineering Technology Research Center for Ecological Carbon Sink and Capture Utilization, Jinan 250022, People's Republic of China.
authors.forename: Caiyun
authors.initials: C
authors.lastname: Liu
authors.affiliation: School of Resources and Environment, University of Jinan , Shandong Provincial Engineering Technology Research Center for Ecological Carbon Sink and Capture Utilization, Jinan 250022, People's Republic of China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Resources and Environment, University of Jinan , Shandong Provincial Engineering Technology Research Center for Ecological Carbon Sink and Capture Utilization, Jinan 250022, People's Republic of China.
authors.forename: Zuokai
authors.initials: Z
authors.lastname: Wang
authors.affiliation: School of Resources and Environment, University of Jinan , Shandong Provincial Engineering Technology Research Center for Ecological Carbon Sink and Capture Utilization, Jinan 250022, People's Republic of China.
authors.forename: Yawei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: College of Chemistry, Chemical Engineering and Materials Science, Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong, Key Laboratory of Molecular and Nano Probes, Ministry of Education, Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals, Institute of Biomedical Sciences, Shandong Normal University , Jinan 250014, People's Republic of China.
authors.forename: Bo
authors.identifier: 0000-0002-8712-7025
authors.initials: B
authors.lastname: Tang
mesh_terms: D000818:Animals; D005456:Fluorescent Dyes / Q000737:chemistry*; D056945:Hep G2 Cells; D006801:Humans; D006997:Hypochlorous Acid / Q000032:analysis*; D008247:Lysosomes / Q000737:chemistry* / Q000648:ultrastructure; D008264:Macrophages / Q000737:chemistry / Q000648:ultrastructure; D051379:Mice; D036641:Microscopy, Fluorescence, Multiphoton / Q000379:methods; D061848:Optical Imaging / Q000379:methods*; D013859:Thiocarbamates / Q000737:chemistry*
chemical_list: D005456:Fluorescent Dyes; D013859:Thiocarbamates; C492475:dimethylthiocarbamate; D006997:Hypochlorous Acid