{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T23:46:15Z","timestamp":1777506375012,"version":"3.51.4"},"reference-count":43,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2016,10,12]],"date-time":"2016-10-12T00:00:00Z","timestamp":1476230400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"The National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No. 20876180"],"award-info":[{"award-number":["No. 20876180"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Photoactivatable fluorophores have become an important technique for the high spatiotemporal resolution of biological imaging. Here, we developed a novel photoactivatable probe (PHBT), which is based on 2-(2-hydroxyphenyl)benzothiazole (HBT), a small organic fluorophore known for its classic luminescence mechanism through excited-state intramolecular proton transfer (ESIPT) with the keto form and the enol form. After photocleavage, PHBT released a ratiometric fluorophore HBT, which showed dual emission bands with more than 73-fold fluorescence enhancement at 512 nm in buffer and more than 69-fold enhancement at 452 nm in bovine serum. The probe displayed a high ratiometric imaging resolution and is believed to have a wide application in biological imaging.<\/jats:p>","DOI":"10.3390\/s16101684","type":"journal-article","created":{"date-parts":[[2016,10,12]],"date-time":"2016-10-12T10:18:49Z","timestamp":1476267529000},"page":"1684","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["ESIPT-Based Photoactivatable Fluorescent Probe for Ratiometric Spatiotemporal Bioimaging"],"prefix":"10.3390","volume":"16","author":[{"given":"Xiaohong","family":"Zhou","sequence":"first","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China"},{"name":"Environment Monitoring Department, Changsha Environmental Protection College, Changsha 410004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuren","family":"Jiang","sequence":"additional","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiongjie","family":"Zhao","sequence":"additional","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dong","family":"Guo","sequence":"additional","affiliation":[{"name":"College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,10,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"25416","DOI":"10.3390\/s151025416","article-title":"Does laser surgery interfere with optical nerve identification in maxillofacial hard and soft tissue?\u2014An experimental ex vivo study","volume":"15","author":"Bergauer","year":"2015","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"828","DOI":"10.1021\/ar200021p","article-title":"Photoinducible bioorthogonal chemistry: A spatiotemporally controllable tool to visualize and perturb proteins in live cells","volume":"44","author":"Lim","year":"2011","journal-title":"Acc. Chem. Res."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1181","DOI":"10.1038\/nmeth.2214","article-title":"Ultrabright photoactivatable fluorophores created by reductive caging","volume":"9","author":"Vaughan","year":"2012","journal-title":"Nat. Methods"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3645","DOI":"10.1073\/pnas.87.10.3645","article-title":"2-Azido-[32P]NAD+, a photoactivatable probe for G-protein structure: Evidence for holotransducin oligomers in which the ADP-ribosylated carboxyl terminus of a interacts with both a and y subunits","volume":"87","author":"Vaillancourt","year":"1990","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_5","first-page":"17436","article-title":"Counting single photoactivatable fluorescent molecules by photoactivated localization microscopy (PALM)","volume":"109","author":"Lee","year":"2012","journal-title":"Bustamante"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"303","DOI":"10.2174\/1567203054637542","article-title":"Unnatural protein engineering: Producing proteins with unnatural amino acids","volume":"2","author":"Magliery","year":"2005","journal-title":"Med. Chem. Rev. Online"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"613","DOI":"10.1016\/j.chembiol.2005.06.006","article-title":"Spatial control of protein synthesis","volume":"12","author":"Koh","year":"2005","journal-title":"Chem. Biol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1016\/S0076-6879(10)75005-9","article-title":"Chapter five-single-particle tracking photoactivated localization microscopy for mapping single-molecule dynamics","volume":"475","author":"Manley","year":"2010","journal-title":"Methods Enzymol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1352","DOI":"10.1002\/ange.200461458","article-title":"Light-activated RNA interference","volume":"117","author":"Shah","year":"2005","journal-title":"Angew. Chem."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"15811","DOI":"10.1021\/ja804948s","article-title":"Caged quantum dots","volume":"130","author":"Han","year":"2008","journal-title":"J. Am. Chem. Soc."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1016\/j.colsurfa.2012.03.022","article-title":"Compact PEGylated polymer-caged quantum dots with improved stability","volume":"402","author":"Zhang","year":"2012","journal-title":"Colloids Surf. A"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"5626","DOI":"10.1021\/acs.analchem.5b00691","article-title":"Localizable and photoactivatable fluorophore for spatiotemporal two-photon bioimaging","volume":"87","author":"Zhou","year":"2015","journal-title":"Anal. Chem."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"6696","DOI":"10.1021\/ja070376d","article-title":"Highly activatable and rapidly releasable caged fluorescein derivatives","volume":"129","author":"Kobayashi","year":"2007","journal-title":"J. Am. Chem. Soc."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"301","DOI":"10.1021\/ja00209a055","article-title":"Photoactivable fluorophores. 3. Synthesis and photoactivation of fluorogenic difunctionalized fluoresceins","volume":"110","author":"Krafft","year":"1988","journal-title":"J. Am. Chem. Soc."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"4653","DOI":"10.1021\/ja036958m","article-title":"New caged coumarin fluorophores with extraordinary uncaging cross sections suitable for biological imaging applications","volume":"126","author":"Zhao","year":"2004","journal-title":"J. Am. Chem. Soc."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"2181","DOI":"10.1016\/S0960-894X(01)00421-8","article-title":"Caged Q-rhodamine dextran: A new photoactivated fluorescent tracer","volume":"11","author":"Gee","year":"2001","journal-title":"Bioorg. Med. Chem. Lett."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"10616","DOI":"10.1021\/ja071427+","article-title":"Photoactivatable and water soluble FRET dyes with high uncaging cross section","volume":"129","author":"Zheng","year":"2007","journal-title":"J. Am. Chem. Soc."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"2379","DOI":"10.1021\/jz301021e","article-title":"Photoactivatable synthetic dyes for fluorescence imaging at the nanoscale","volume":"3","author":"Raymo","year":"2012","journal-title":"J. Phys. Chem. Lett."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1021\/cr300177k","article-title":"Photoremovable protecting groups in chemistry and biology: Reaction mechanisms and efficacy","volume":"113","author":"Bochet","year":"2013","journal-title":"J. Chem. Rev."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"14840","DOI":"10.1039\/c3cp51822a","article-title":"Photoactivatable synthetic fluorophores","volume":"15","author":"Raymo","year":"2013","journal-title":"Phys. Chem. Chem. Phys."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"16766","DOI":"10.1021\/ja407867a","article-title":"Expansion of bioorthogonal chemistries towards site-specific polymer-protein conjugation","volume":"135","author":"Yu","year":"2013","journal-title":"J. Am. Chem. Soc."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"10276","DOI":"10.1002\/chem.201403509","article-title":"Plasmonic activation of a fluorescent Carbazole\u2013Oxazine switch","volume":"20","author":"Sortino","year":"2014","journal-title":"Chem. Eur. J."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2620","DOI":"10.1039\/B202719B","article-title":"Aromatic 2-(2\u2032-hydroxyphenyl)benzoxazole esters: A novel class of caged photoluminescent dyes","volume":"12","author":"Kocher","year":"2002","journal-title":"J. Mater. Chem."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2384","DOI":"10.1021\/jp5068507","article-title":"2-(2-hydroxyphenyl)-benzothiazole (HBT)-rhodamine dyad: Acid-switchable absorption and fluorescence of excited-state intramolecular proton transfer (ESIPT)","volume":"119","author":"Majumdar","year":"2015","journal-title":"J. Phys. Chem. B"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1016\/j.chemphys.2014.10.006","article-title":"Intramolecular photoinduced proton transfer in 2-(2\u2032-hydroxyphenyl)benzazole family: A TD-DFT quantum chemical study","volume":"444","author":"Roohi","year":"2014","journal-title":"Chem. Phys."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"80283","DOI":"10.1039\/C5RA17980G","article-title":"Highly emissive excited-state intramolecular proton transfer (ESIPT) inspired 2-(2\u2032-hydroxy)benzothiazole-fluorene motifs: Spectroscopic and photophysical properties investigation","volume":"5","author":"Padalkar","year":"2015","journal-title":"RSC Adv."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"7539","DOI":"10.1021\/ja012646c","article-title":"Excited state proton transfer in reverse micelles","volume":"124","author":"Cohen","year":"2002","journal-title":"J. Am. Chem. Soc."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1383","DOI":"10.1021\/jz400437q","article-title":"Excited-state proton-transfer processes of DHICA resolved: From sub-picoseconds to nanoseconds","volume":"4","author":"Corani","year":"2013","journal-title":"J. Phys. Chem. Lett."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"9720","DOI":"10.1039\/c2cc35210a","article-title":"New excited state intramolecular proton transfer (ESIPT) dyes based on naphthalimide and observation of long-lived triplet excited states","volume":"48","author":"Ma","year":"2012","journal-title":"Chem. Commun."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"3568","DOI":"10.1039\/c1jm00009h","article-title":"Hydroxyphenyl-benzothiazole based full color organic emitting materials generated by facile molecular modification","volume":"21","author":"Yao","year":"2011","journal-title":"J. Mater. Chem."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1915","DOI":"10.1021\/j100368a036","article-title":"Mechanism of the ground-state reverse proton transfer of 2-(2-hydroxyphenyl) benzothiazole","volume":"94","author":"Brewer","year":"1990","journal-title":"J. Phys. Chem."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"6166","DOI":"10.1021\/jo300943t","article-title":"Accessing the long-lived triplet excited states in bodipy-conjugated 2-(2-hydroxyphenyl) benzothiazole\/benzoxazoles and applications as organic triplet","volume":"77","author":"Yang","year":"2012","journal-title":"J. Org. Chem."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"34572","DOI":"10.1039\/C4RA05714G","article-title":"FRET based \u2018red-switch\u2019 for Al3+ over ESIPT based \u2018green-switch\u2019 for Zn2+: Dual channel detection with live-cell imaging on a dyad platform","volume":"4","author":"Goswami","year":"2014","journal-title":"RSC Adv."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"20139","DOI":"10.1039\/C5DT03719K","article-title":"A 2-(2\u2032-hydroxyphenyl)benzothiazole (HBT)\u2013quinoline conjugate: A highly specific fluorescent probe for Hg(2+) based on ESIPT and its application in bioimaging","volume":"44","author":"Sahana","year":"2015","journal-title":"Dalton Trans."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1016\/j.dyepig.2015.04.016","article-title":"\u201cQuinone\u2013phenol\u201d transduction activated excited-state intramolecular proton transfer: A new strategy toward ratiometric fluorescent probe for sulfite in living cells","volume":"120","author":"Geng","year":"2015","journal-title":"Dyes Pigment"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1016\/j.chemphys.2006.11.007","article-title":"Photo-physical properties of 1-hydroxy-2-naphthaldehyde: A combined fluorescence spectroscopy and quantum chemical calculations","volume":"331","author":"Singh","year":"2007","journal-title":"Chem. Phys."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1021\/jp026404q","article-title":"Excited state prototropic activities in 2-hydroxy 1-naphthaldehyde","volume":"107","author":"Chowdhury","year":"2003","journal-title":"J. Phys. Chem. A"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1016\/j.cplett.2003.11.058","article-title":"Competitive intramolecular hydrogen bonding formation and excited-state proton transfer reaction in 1-[(diethylamino)-methyl]-2-hydroxy-3-naphthaldehyde","volume":"384","author":"Wu","year":"2004","journal-title":"Chem. Phys. Lett."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"742","DOI":"10.1016\/j.chemphys.2006.01.036","article-title":"Excited state intramolecular proton transfer in 3-hydroxy-2-naphthaldehyde: A combined study by absorption and emission spectroscopy and quantum chemical","volume":"324","author":"Mahanta","year":"2006","journal-title":"Chem. Phys."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"2596","DOI":"10.1021\/jp508777h","article-title":"Solvent-dependent excited-state hydrogen transfer and intersystem crossing in 2-(2\u2032-Hydroxyphenyl)-Benzothiazole","volume":"119","author":"Aly","year":"2015","journal-title":"J. Phys. Chem. B"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1016\/j.jphotochem.2009.03.025","article-title":"Substituent and solvent effects on excited state intramolecular proton transfer in novel 2-(2\u2032-hydroxyphenyl)benzothiazole derivatives","volume":"205","author":"Wang","year":"2009","journal-title":"J. Photochem. Photobiol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"3278","DOI":"10.1016\/j.surfcoat.2005.07.060","article-title":"Solvent effect of excited state intramolecular proton transfer in 2-(2\u2032-hydroxyphenyl)benzothiazole upon luminescent properties","volume":"200","author":"Chang","year":"2006","journal-title":"Surf. Coat. Technol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"8747","DOI":"10.1039\/c3ra40907d","article-title":"Spectroscopy of hydroxyphenyl benzazoles in solution and human serum albumin: Detecting flexibility, specificity and high affinity of the warfarin drug binding site","volume":"3","year":"2013","journal-title":"RSC Adv."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/16\/10\/1684\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T19:32:48Z","timestamp":1760211168000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/16\/10\/1684"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,10,12]]},"references-count":43,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2016,10]]}},"alternative-id":["s16101684"],"URL":"https:\/\/doi.org\/10.3390\/s16101684","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,10,12]]}}}