{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,26]],"date-time":"2026-04-26T01:33:34Z","timestamp":1777167214156,"version":"3.51.4"},"reference-count":50,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2018,6,30]],"date-time":"2018-06-30T00:00:00Z","timestamp":1530316800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003593","name":"Conselho Nacional de Desenvolvimento Cient\u00edfico e Tecnol\u00f3gico","doi-asserted-by":"publisher","award":["202553\/2014-0"],"award-info":[{"award-number":["202553\/2014-0"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004901","name":"Funda\u00e7\u00e3o de Amparo \u00e0 Pesquisa do Estado de Minas Gerais","doi-asserted-by":"publisher","award":["APQ-00360-14"],"award-info":[{"award-number":["APQ-00360-14"]}],"id":[{"id":"10.13039\/501100004901","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Chemosensors"],"abstract":"<jats:p>Fluorescein and its derivatives are yellowish-green emitting dyes with outstanding potential in advanced molecular probes for different applications. In this work, two fluorescent compounds containing fluorescein and an amino acid residue (compounds 1 and 2) were photophysically explored. Compounds 1 and 2 were previously synthesized via ester linkage between fluorescein ethyl ester and Boc-ser (TMS)-OH or Boc-cys(4-methyl benzyl)-OH. Studies on the time-resolved fluorescence lifetime and relative fluorescence quantum yield (\u03c6) were performed for 1 and 2 diluted in acetonitrile, ethanol, dimethyl sulfoxide, and tetrahydrofuran solvents. The discussion considered the dielectric constants of the studied solvents (range between 7.5 and 47.2) and the photophysical parameters. The results of the lifetime and \u03c6 were compared with those obtained for compounds 1, 2 and fluorescein without an amino acid residue in alkaline aqueous solutions. Moreover, as a preliminary result compound 2 (S-cysteine) was tested in the presence of gold nanoparticles as an aggregation colorimetric probe.<\/jats:p>","DOI":"10.3390\/chemosensors6030026","type":"journal-article","created":{"date-parts":[[2018,7,2]],"date-time":"2018-07-02T10:56:52Z","timestamp":1530529012000},"page":"26","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Lifetime and Fluorescence Quantum Yield of Two Fluorescein-Amino Acid-Based Compounds in Different Organic Solvents and Gold Colloidal Suspensions"],"prefix":"10.3390","volume":"6","author":[{"given":"Viviane","family":"Pilla","sequence":"first","affiliation":[{"name":"BIOSCOPE Group, LAQV-REQUIMTE, Chemistry Department, Faculty of Science and Technology, University NOVA of Lisbon, 2829-516 Caparica, Portugal"},{"name":"Instituto de F\u00edsica, Universidade Federal de Uberl\u00e2ndia-UFU, Av. Jo\u00e3o Naves de \u00c1vila 2121, 38400-902 Uberl\u00e2ndia, Brazil"}]},{"given":"Augusto C.","family":"Gon\u00e7alves","sequence":"additional","affiliation":[{"name":"BIOSCOPE Group, LAQV-REQUIMTE, Chemistry Department, Faculty of Science and Technology, University NOVA of Lisbon, 2829-516 Caparica, Portugal"},{"name":"Instituto de Qu\u00edmica, Universidade de S\u00e3o Paulo-USP, Av. Prof. Lineu Prestes 748, CxP 26077, 05508-000 S\u00e3o Paulo, Brazil"}]},{"given":"Alcindo A.","family":"Dos Santos","sequence":"additional","affiliation":[{"name":"Instituto de Qu\u00edmica, Universidade de S\u00e3o Paulo-USP, Av. Prof. Lineu Prestes 748, CxP 26077, 05508-000 S\u00e3o Paulo, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5582-5446","authenticated-orcid":false,"given":"Carlos","family":"Lodeiro","sequence":"additional","affiliation":[{"name":"BIOSCOPE Group, LAQV-REQUIMTE, Chemistry Department, Faculty of Science and Technology, University NOVA of Lisbon, 2829-516 Caparica, Portugal"},{"name":"Proteomass Scientific Society, Rua dos Inventores, Madan Park, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2018,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2559","DOI":"10.1016\/j.bmc.2005.11.037","article-title":"Fluorescein-Based Amino Acids for Solid Phase Synthesis of Fluorogenic Protease Substrates","volume":"14","author":"Burchak","year":"2006","journal-title":"Bioorg. Med. Chem."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1002\/open.201700135","article-title":"Green and Red Fluorescent Dyes for Translational Applications in Imaging and Sensing Analytes: A Dual-Color Flag","volume":"7","author":"Oliveira","year":"2018","journal-title":"ChemistryOpen"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"9590","DOI":"10.1021\/ja502292p","article-title":"Thermally Activated Delayed Fluorescence of Fluorescein Derivative for Time-Resolved and Confocal Fluorescence Imaging","volume":"136","author":"Xiong","year":"2014","journal-title":"J. Am. Chem. Soc."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1039\/C2CC35997A","article-title":"Advances in Modifying Fluorescein and Rhodamine Fluorophores as Fluorescent Chemosensors","volume":"49","author":"Zheng","year":"2013","journal-title":"Chem. Commun."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"L7","DOI":"10.1016\/0584-8539(95)01421-P","article-title":"Absorption and Fluorescence Properties of Fluorescein","volume":"51","author":"Nygren","year":"1995","journal-title":"Spectrochim. Acta A"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"819","DOI":"10.1007\/s10895-014-1356-5","article-title":"Fluorescence Properties of Twenty Fluorescein Derivatives: Lifetime, Quantum Yield, Absorption and Emission Spectra","volume":"24","author":"Zhang","year":"2014","journal-title":"J. Fluoresc."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"3000","DOI":"10.1039\/c2cc17184h","article-title":"A New Selective Fluorogenic Probe for Trivalent Cations","volume":"48","author":"Costero","year":"2012","journal-title":"Chem. Commun."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1016\/S0927-7757(99)00313-1","article-title":"Spectral Properties and Structure of Fluorescein and its Alkyl Derivatives in Micelles","volume":"167","author":"Song","year":"2000","journal-title":"Colloids Surf. A Physicochem. Eng. Asp."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"381","DOI":"10.1016\/0022-2313(75)90003-4","article-title":"The pH Dependence of Fluorescein Fluorescence","volume":"10","author":"Martin","year":"1975","journal-title":"J. Lumin."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1016\/0022-2860(86)85094-3","article-title":"Photophysics Properties of Fluorescein in Alcoholic Medium for Different pH","volume":"142","author":"Martin","year":"1986","journal-title":"J. Mol. Struct."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1113","DOI":"10.1016\/0584-8539(89)80189-8","article-title":"The Absorption and Structure of Fluorescein and its Ethyl Derivatives in Various Solutions","volume":"45","author":"Zhao","year":"1989","journal-title":"Spectrochim. Acta A"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"371","DOI":"10.1016\/S0143-7208(98)00022-9","article-title":"Syntheses and Photophysical Properties of Amphiphilic Dyads of Fluorescein and Carbazole Linked with a Flexible or Semi-rigid Bridge","volume":"39","author":"Song","year":"1998","journal-title":"Dyes Pigments"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1016\/0009-2614(75)85598-9","article-title":"Hydrogen Bond Effects on Radiationless Electronic Transitions in Xanthene Dyes","volume":"35","author":"Martin","year":"1975","journal-title":"Chem. Phys. Lett."},{"key":"ref_14","first-page":"500","article-title":"Spectral Properties of Fluorescein in Solvent-Water Mixtures: Applications as a Probe of Hydrogen Bonding Environments in Biological Systems","volume":"67","author":"Klonis","year":"1998","journal-title":"Photochem. Photobiol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1134\/S0036024407010219","article-title":"Effect of the Solvent on the Absorption Spectra and Protonation of Fluorescein Dye Anions","volume":"81","author":"Ivanov","year":"2007","journal-title":"Russ. J. Phys. Chem. A"},{"key":"ref_16","first-page":"011105","article-title":"Solvent Effects on the Electronic Absorption and Fluorescence Spectra","volume":"2","author":"Homocianu","year":"2017","journal-title":"J. Adv. Res. Phys."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"737","DOI":"10.1111\/j.1751-1097.1999.tb08277.x","article-title":"Solvent Dependence of the Fluorescence Lifetimes of Xanthene Dyes","volume":"70","author":"Magde","year":"1999","journal-title":"Photochem. Photobiol."},{"key":"ref_18","first-page":"519","article-title":"Fluorescence and Lasing Characteristics of Fluorescein Calix[4]aryl Hydroxamic Acid","volume":"10","author":"Gidwani","year":"2003","journal-title":"Indian J. Chem. Technol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"563","DOI":"10.1142\/S0217984999000725","article-title":"Solvent Effect on Absolute Fluorescence Quantum Yield of Rhodamine 6G Determined Using Transient Thermal Lens Technique","volume":"13","author":"Bindhu","year":"1999","journal-title":"Mod. Phys. Lett. B"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"3222","DOI":"10.1063\/1.372327","article-title":"Solvent Dependent Nonlinear Refraction in Organic Dye Solution","volume":"87","author":"Sinha","year":"2000","journal-title":"J. Appl. Phys."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1562\/0031-8655(2002)075<0327:FQYATR>2.0.CO;2","article-title":"Fluorescence Quantum Yields and Their Relation to Lifetimes of Rhodamine 6G and Fluorescein in Nine Solvents: Improved Absolute Standards for Quantum Yields","volume":"75","author":"Magde","year":"2002","journal-title":"Photochem. Photobiol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"9513","DOI":"10.1039\/C6DT01180B","article-title":"The Interaction of Hg2+ and Trivalent Ions with Two New Fluorescein Bio-inspired Dual Colorimetric\/Fluorimetric Probes","volume":"45","author":"Pilla","year":"2016","journal-title":"Dalton Trans."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"54777","DOI":"10.1039\/C6RA12222A","article-title":"Gold Nanoparticle Synthesis Coupled to Fluorescence Turn-on for Sensitive Detection of Formaldehyde using Formaldehyde Dehydrogenase","volume":"6","author":"Akshath","year":"2016","journal-title":"RSC Adv."},{"key":"ref_24","first-page":"753","article-title":"Breast Cancer Imaging with Fluoresce in Isothiocyanate-Modified Gold Nanoparticles In-Vidro and In-Vivo","volume":"9","author":"Yang","year":"2016","journal-title":"Int. J. Clin. Exp. Med."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2560","DOI":"10.1039\/c3ay41957f","article-title":"Detection of Immunoglobulin G based on Nanoparticle Surface Energy Transfers from Fluorescein Isothiocyanate to Gold Nanoparticles","volume":"6","author":"Tao","year":"2014","journal-title":"Anal. Methods"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"3912","DOI":"10.1007\/s12274-015-0891-y","article-title":"An Ultra-Sensitive Dual-Mode Imaging System Using Metal-Enhanced Fluorescence in Solid Phantoms","volume":"8","author":"Barnoy","year":"2015","journal-title":"Nano Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"2581","DOI":"10.1039\/C6AN00165C","article-title":"A Dual-Mode Signaling Response of a AuNP-Fluorescein Based Probe for Specific Detection of Thiourea","volume":"141","author":"Chen","year":"2016","journal-title":"Analyst"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"683","DOI":"10.1166\/jbn.2009.1085","article-title":"p53 Detection by Fluorescence Lifetime on a Hybrid Fluorescein Isothiocyanate Gold Nanosensor","volume":"5","author":"Sironi","year":"2009","journal-title":"J. Biomed. Nanotechnol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"22839","DOI":"10.1021\/acsami.6b06331","article-title":"Construction of pH-Sensitive \u201cSubmarine\u201d Based on Gold Nanoparticles with Double Insurance for Intracellular pH Mapping, Quantifying of Whole Cells and in Vivo Applications","volume":"8","author":"Yu","year":"2016","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1828","DOI":"10.1007\/s11051-013-1828-6","article-title":"1D Chain Fluorescein-Functionalized Gold and Silver Nanoparticles as New Optical Mercury Chemosensor in Aqueous Media","volume":"15","author":"Oliveira","year":"2013","journal-title":"J. Nanopart. Res."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"12723","DOI":"10.1039\/C6NR02228F","article-title":"A Smart Multifunctional Drug Delivery Nanoplatform for Targeting Cancer Cells","volume":"8","author":"Hoop","year":"2016","journal-title":"Nanoscale"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1314","DOI":"10.1021\/acsomega.6b00309","article-title":"Unraveling the Organotellurium Chemistry Applied to the Synthesis of Gold Nanomaterials","volume":"1","author":"Santos","year":"2016","journal-title":"ACS Omega"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Montalti, M., Credi, A., Prodi, L., and Gandolfi, M.T. (2006). Handbook of Photochemistry, Taylor & Francis. [3rd ed.].","DOI":"10.1201\/9781420015195"},{"key":"ref_34","unstructured":"Wypych, G. (2001). Handbook of Solvents, ChemTec Publishing and William Andrew Inc."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/j.theochem.2003.12.011","article-title":"Structural, Energetic, and Electronic Properties of (CH3CN)2-8 Clusters by Density Functional Theory","volume":"673","author":"Mata","year":"2004","journal-title":"J. Mol. Struct. (THEOCHEM)"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"603","DOI":"10.1016\/0584-8539(94)00164-7","article-title":"Quantitative Treatment of the Solvent Effects on the Electronic Absorption and Fluorescence Spectra of Acridines and Phenazines. The Ground and First Excited Singlet-State Dipole Moments","volume":"51","author":"Aaron","year":"1995","journal-title":"Spectrochim. Acta"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"15042","DOI":"10.1021\/jp106601a","article-title":"Effect of Ionic Liquid on Prototropic and Solvatochromic Behavior of Fluorescein","volume":"114","author":"Ali","year":"2010","journal-title":"J. Phys. Chem. B"},{"key":"ref_38","first-page":"34","article-title":"Effect of Solvents on the Dipole Moments and Fluorescence Quantum Yield of Rhodamine Dyes","volume":"9","author":"AbdAlfahdaw","year":"2013","journal-title":"ISESCO J. Sci. Technol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"6320","DOI":"10.1021\/jp010372+","article-title":"Fluorescein Excited-State Proton Exchange Reactions: Nanosecond Emission Kinetics and Correlation with Steady-State Fluorescence Intensity","volume":"105","author":"Ballesteros","year":"2001","journal-title":"J. Phys. Chem. A"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"14079","DOI":"10.1021\/ja048241k","article-title":"Rational Principles for Modulating Fluorescence Properties of Fluorescein","volume":"126","author":"Ueno","year":"2004","journal-title":"J. Am. Chem. Soc."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"814","DOI":"10.1063\/1.1733166","article-title":"Relationship Between Absorption Intensity and Fluorescence Lifetime of Molecules","volume":"37","author":"Strickler","year":"1962","journal-title":"J. Chem. Phys."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1261","DOI":"10.1039\/c0pp00184h","article-title":"The Effect of Phenyl Substitution on the Fluorescence Characteristics of Fluorescein Derivatives via Intramolecular Photoinduced Electron Transfer","volume":"9","author":"Zhang","year":"2010","journal-title":"Photochem. Photobiol. Sci."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"643","DOI":"10.1023\/B:STUC.0000007575.53499.d0","article-title":"Quantum Mechanical Studies of Intensity in Electronic Spectra of Fluorescein Dianion and Monoanion Forms","volume":"14","author":"Tamulis","year":"2003","journal-title":"Struct. Chem."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/j.dyepig.2009.11.002","article-title":"Protolytic Fluorescein Species Evaluated Using Chemometry and DFT Studies","volume":"86","author":"Batistela","year":"2010","journal-title":"Dyes Pigments"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"2757","DOI":"10.1021\/jp808121y","article-title":"Investigating Tryptophan Quenching of Fluorescein Fluorescence under Protolytic Equilibrium","volume":"113","author":"Togashi","year":"2009","journal-title":"J. Phys. Chem. A"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"2137","DOI":"10.1021\/ac062160k","article-title":"Fluorescence Lifetime Standards for Time and Frequency Domain Fluorescence Spectroscopy","volume":"79","author":"Boens","year":"2007","journal-title":"Anal. Chem."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"2315","DOI":"10.1007\/s11051-014-2315-4","article-title":"New-coated Fluorescent Silver Nanoparticles with a Fluorescein Thiol Esther Derivative: Fluorescent Enhancement upon Interaction with Heavy Metal Ions","volume":"16","author":"Oliveira","year":"2014","journal-title":"J. Nanopart. Res."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"025017","DOI":"10.1088\/2043-6262\/5\/2\/025017","article-title":"Environmentally Benign Synthesis of Positively Charged, Ultra-Low Sized Colloidal Gold in Universal Solvent","volume":"5","author":"Kumar","year":"2014","journal-title":"Adv. Nat. Sci. Nanosci. Nanotechnol."},{"key":"ref_49","doi-asserted-by":"crossref","unstructured":"Lu, G.W., and Gao, P. (2010). Handbook of Non-Invasive Drug Delivery Systems; Emulsions and Microemulsions for Topical and Transdermal Drug Delivery, William Andrew. [1st ed.].","DOI":"10.1016\/B978-0-8155-2025-2.10003-4"},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"17862","DOI":"10.1039\/C4RA16294C","article-title":"Positively Charged, Surfactant-Free Gold Nanoparticles for Nuclei Acid Delivery","volume":"5","author":"Guo","year":"2015","journal-title":"RSC Adv."}],"container-title":["Chemosensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2227-9040\/6\/3\/26\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T15:10:51Z","timestamp":1760195451000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2227-9040\/6\/3\/26"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,6,30]]},"references-count":50,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2018,9]]}},"alternative-id":["chemosensors6030026"],"URL":"https:\/\/doi.org\/10.3390\/chemosensors6030026","relation":{},"ISSN":["2227-9040"],"issn-type":[{"value":"2227-9040","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,6,30]]}}}