{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T23:23:59Z","timestamp":1791415439254,"version":"4.3.3"},"reference-count":21,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,5,24]],"date-time":"2025-05-24T00:00:00Z","timestamp":1748044800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ming Chi University of Technology","award":["VL004-1100-113"],"award-info":[{"award-number":["VL004-1100-113"]}]},{"name":"Ming Chi University of Technology","award":["RKAT 2025"],"award-info":[{"award-number":["RKAT 2025"]}]},{"name":"Department of Mechanical Engineering, Universitas Andalas","award":["VL004-1100-113"],"award-info":[{"award-number":["VL004-1100-113"]}]},{"name":"Department of Mechanical Engineering, Universitas Andalas","award":["RKAT 2025"],"award-info":[{"award-number":["RKAT 2025"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The current research developed an optical carbon dioxide (CO2) sensor using anodized aluminum oxide (AAO) as the substrate. We developed an optical carbon dioxide (CO2) sensor utilizing CdSe\/ZnS quantum dots (QDs) as the fluorescent dye and Phenol Red as the pH indicator. The QDs acted as the CO2-responsive fluorophore and were embedded in a polyimide butyl methacrylate (polyIBM) matrix. This sensing solution was applied to an anodized aluminum oxide (AAO) substrate, which provided a porous and stable platform for sensor fabrication. Photoluminescence measurements were conducted using the coated AAO substrate, with excitation from a 405 nm LED light source. The sensor exhibited red fluorescence emission at 570 nm and could detect CO2 concentrations in the linear range of 0\u2013100%. Experimental results showed that fluorescence intensity increased with CO2 concentration, achieving a sensitivity of 211. A wavelength shift of 0.1657 nm\/% was observed, indicating strong interactions among CO2 molecules, Phenol Red, and the QDs within the AAO matrix. The sensor demonstrated a response time of 55 s and a recovery time of 120 s. These results confirm the effectiveness of this optical sensing approach in minimizing fluctuations from the excitation light source and highlight the potential of the AAO-supported QDs and Phenol Red composite as a reliable CO2 sensing material. This advancement holds promise for applications in both medical and industrial fields.<\/jats:p>","DOI":"10.3390\/polym17111460","type":"journal-article","created":{"date-parts":[[2025,5,25]],"date-time":"2025-05-25T20:16:22Z","timestamp":1748204182000},"page":"1460","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Advanced Optimization of Optical Carbon Dioxide Sensor Through Sensitivity Enhancement in Anodic Aluminum Oxide Substrate"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-4113-8926","authenticated-orcid":false,"given":"Manna Septriani","family":"Simanjuntak","sequence":"first","affiliation":[{"name":"International Ph.D. Program in Innovative Technology of Biomedical Engineering and Medical Devices, Ming Chi University of Technology, New Taipei City 243303, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-9928-1481","authenticated-orcid":false,"family":"Rispandi","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Faculty of Engineering, Universitas Andalas, Padang 25163, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cheng-Shane","family":"Chu","sequence":"additional","affiliation":[{"name":"International Ph.D. Program in Innovative Technology of Biomedical Engineering and Medical Devices, Ming Chi University of Technology, New Taipei City 243303, Taiwan"},{"name":"Department of Mechanical Engineering, Ming Chi University of Technology, New Taipei City 243303, Taiwan"},{"name":"Research Center for Intelligent Medical Device, Ming Chi University of Technology, New Taipei City 243303, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Benton, E.N., Perera, N.A.K.R., Nesterov, V.N., Perera, W., Omary, M.A., and Marpu, S.B. (2023). A europium-based optical sensor for the detection of carbon dioxide and its application for a fermentation reaction. Chemosensors, 11.","DOI":"10.3390\/chemosensors11010005"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2764","DOI":"10.1016\/j.snb.2017.09.091","article-title":"Dual-channel sensing of CO2: Reversible solution-gel transition and gelatin-induced fluorescence enhancement","volume":"255","author":"Zhang","year":"2018","journal-title":"Sens. Actuators B Chem."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"76","DOI":"10.1016\/j.snb.2016.04.052","article-title":"A colorimetric and fluorescent chemosensor for the highly sensitive detection of CO2 gas: Experiment and DFT calculation","volume":"233","author":"Sun","year":"2016","journal-title":"Sens. Actuators B Chem."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1016\/j.snb.2013.04.074","article-title":"A new highly sensitive and versatile optical sensing film for controlling CO2 in gaseous and aqueous media","volume":"184","author":"Gutierrez","year":"2013","journal-title":"Sens. Actuators B Chem."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1439","DOI":"10.1016\/S0956-5663(03)00072-1","article-title":"Development of catheter-type optical oxygen sensor and applications to bioinstrumentation","volume":"18","author":"Tsukada","year":"2003","journal-title":"Biosens. Bioelectron."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1016\/j.snb.2009.09.019","article-title":"Highly sensitive and linear optical fiber carbon dioxide sensor based on sol-gel matrix doped with silica particles and HPTS","volume":"143","author":"Chu","year":"2009","journal-title":"Sens. Actuators B Chem."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1308","DOI":"10.1039\/b802918k","article-title":"Plasmon-controlled fluorescence: A new paradigm in fluorescence spectroscopy","volume":"133","author":"Lakowicz","year":"2008","journal-title":"Analyst"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"642","DOI":"10.1007\/s00216-003-1949-3","article-title":"Optical sensor for carbon dioxide combining colorimetric change of a pH indicator and a reference luminescent dye","volume":"376","author":"Nakamura","year":"2003","journal-title":"Anal. Bioanal. Chem."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"976","DOI":"10.1016\/j.talanta.2004.12.058","article-title":"Optical CO2 sensor of the combination of colorimetric change of \u03b1-naphtholphthalein in poly(isobutyl methacrylate) and fluorescent porphyrin in polystyrene","volume":"66","author":"Amao","year":"2005","journal-title":"Talanta"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.reactfunctpolym.2005.02.003","article-title":"Rapid responsible optical CO2 sensor of the combination of colorimetric change of alpha-naphtholphthalein in poly(trimethylsiliylpropyne) layer and internal reference fluorescent porphyrin in polystyrene layer","volume":"63","author":"Amao","year":"2005","journal-title":"React. Funct. Polym."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"857","DOI":"10.1109\/JLT.2017.2730251","article-title":"Fluorescence ratiometric optical broad range pH sensor based on CdSe\/ZnS quantum dots and O170 embedded in ethyl cellulose matrix","volume":"36","author":"Chu","year":"2018","journal-title":"J. Ligthtwave Tech."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"347","DOI":"10.1016\/j.snb.2004.02.003","article-title":"Optical CO2 sensor with the combination of colorimetric change of \u03b1-naphtholphthalein and internal reference fluorescent porphyrin dye","volume":"100","author":"Amao","year":"2004","journal-title":"Sens. Actuators B Chem."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"403","DOI":"10.1016\/j.nimb.2008.10.055","article-title":"Plasmon-enhanced fluorescence of dye molecules","volume":"267","author":"Baldeck","year":"2009","journal-title":"Nucl. Instru. Meth. B"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"083901","DOI":"10.1063\/1.3086283","article-title":"Metal-enhanced bioluminescence: An approach for monitoring biological luminescent processes","volume":"94","author":"Eltzov","year":"2009","journal-title":"Appl. Phys. Lett."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"7487","DOI":"10.1021\/cr500002z","article-title":"Porous Anodic Aluminum Oxide: Anodization and Templated Synthesis of Functional Nanostructures","volume":"114","author":"Lee","year":"2014","journal-title":"Chem. Rev."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1466","DOI":"10.1126\/science.268.5216.1466","article-title":"Ordered Metal Nanohole Arrays Made by a Two-Step Replication of Honeycomb Structures of Anodic Alumina","volume":"268","author":"Masuda","year":"1994","journal-title":"Science"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"6023","DOI":"10.1063\/1.368911","article-title":"Hexagonal pore arrays with a 50\u2013420 nm interpore distance formed by self-organization in anodic alumina","volume":"84","author":"Li","year":"1998","journal-title":"J. Appl. Phys."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1016\/j.micromeso.2019.05.056","article-title":"Nanoplatform based on ideally ordered arrays of short straight and long beer bottle-shaped nanochannels","volume":"287","author":"Liu","year":"2019","journal-title":"Mesoporous Mater."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"132712","DOI":"10.1016\/j.snb.2022.132712","article-title":"Achieving high response of poly (3-hexylthiophene-2,5-diyl) molecules to gaseous ammonia using anodic aluminum oxide nanoporous substrate operated under 1 V","volume":"373","author":"Biring","year":"2022","journal-title":"Sens. Actuators B Chem."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"945","DOI":"10.1364\/OME.487332","article-title":"Ratiometric optical oxygen sensor based on perovskite quantum dots and Rh110 embedded in an ethyl cellulose matrix","volume":"13","author":"Mesin","year":"2023","journal-title":"Opt. Mater. Express"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1016\/S0039-9140(02)00495-2","article-title":"Characterization of a reservoir-type capillary optical microsensor for pCO2 measurements","volume":"59","author":"Ertekin","year":"2003","journal-title":"Talanta"}],"container-title":["Polymers"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4360\/17\/11\/1460\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T17:39:46Z","timestamp":1760031586000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4360\/17\/11\/1460"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,5,24]]},"references-count":21,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2025,6]]}},"alternative-id":["polym17111460"],"URL":"https:\/\/doi.org\/10.3390\/polym17111460","relation":{},"ISSN":["2073-4360"],"issn-type":[{"value":"2073-4360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,5,24]]}}}