{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T02:23:19Z","timestamp":1778552599298,"version":"3.51.4"},"reference-count":50,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2019,11,16]],"date-time":"2019-11-16T00:00:00Z","timestamp":1573862400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100014440","name":"Ministerio de Ciencia, Innovaci\u00f3n y Universidades","doi-asserted-by":"publisher","award":["CTQ2014-56370-R"],"award-info":[{"award-number":["CTQ2014-56370-R"]}],"id":[{"id":"10.13039\/100014440","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100014440","name":"Ministerio de Ciencia, Innovaci\u00f3n y Universidades","doi-asserted-by":"publisher","award":["CTQ2017-85658-R"],"award-info":[{"award-number":["CTQ2017-85658-R"]}],"id":[{"id":"10.13039\/100014440","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In the last few years, quantum dot (QD) nanoparticles have been employed for bioimaging and sensing due to their excellent optical features. Most studies have used photoluminescence (PL) intensity-based techniques, which have some drawbacks, especially when working with nanoparticles in intracellular media, such as fluctuations in the excitation power, fluorophore concentration dependence, or interference from cell autofluorescence. Some of those limitations can be overcome with the use of time-resolved spectroscopy and fluorescence lifetime imaging microscopy (FLIM) techniques. In this work, CdSe\/ZnS QDs with long decay times were modified with aminophenylboronic acid (APBA) to achieve QD-APBA conjugates, which can act as glucose nanosensors. The attachment of the boronic acid moiety on the surface of the nanoparticle quenched the PL average lifetime of the QDs. When glucose bonded to the boronic acid, the PL was recovered and its lifetime was enhanced. The nanosensors were satisfactorily applied to the detection of glucose into MDA-MB-231 cells with FLIM. The long PL lifetimes of the QD nanoparticles made them easily discernible from cell autofluorescence, thereby improving selectivity in their sensing applications. Since the intracellular levels of glucose are related to the metabolic status of cancer cells, the proposed nanosensors could potentially be used in cancer diagnosis.<\/jats:p>","DOI":"10.3390\/s19224992","type":"journal-article","created":{"date-parts":[[2019,11,18]],"date-time":"2019-11-18T04:31:10Z","timestamp":1574051470000},"page":"4992","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["A Quantum Dot-Based FLIM Glucose Nanosensor"],"prefix":"10.3390","volume":"19","author":[{"given":"Consuelo","family":"Ripoll","sequence":"first","affiliation":[{"name":"Department Physical Chemistry, Faculty of Pharmacy, Unidad de Excelencia de Qu\u00edmica Aplicada a la Biomedicinay Medioambiente (UEQABM), University of Granada, Campus Cartuja, 18071 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1905-4183","authenticated-orcid":false,"given":"Angel","family":"Orte","sequence":"additional","affiliation":[{"name":"Department Physical Chemistry, Faculty of Pharmacy, Unidad de Excelencia de Qu\u00edmica Aplicada a la Biomedicinay Medioambiente (UEQABM), University of Granada, Campus Cartuja, 18071 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lorena","family":"Paniza","sequence":"additional","affiliation":[{"name":"Department Physical Chemistry, Faculty of Pharmacy, Unidad de Excelencia de Qu\u00edmica Aplicada a la Biomedicinay Medioambiente (UEQABM), University of Granada, Campus Cartuja, 18071 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0853-187X","authenticated-orcid":false,"given":"Maria Jose","family":"Ruedas-Rama","sequence":"additional","affiliation":[{"name":"Department Physical Chemistry, Faculty of Pharmacy, Unidad de Excelencia de Qu\u00edmica Aplicada a la Biomedicinay Medioambiente (UEQABM), University of Granada, Campus Cartuja, 18071 Granada, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1132","DOI":"10.1016\/j.cell.2012.02.032","article-title":"Cellular metabolism and disease: What do metabolic outliers teach us?","volume":"148","author":"DeBerardinis","year":"2012","journal-title":"Cell"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2482","DOI":"10.1021\/cr068069y","article-title":"Electrochemical Glucose Sensors and Their Applications in Diabetes Management","volume":"108","author":"Heller","year":"2008","journal-title":"Chem. 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