{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T11:05:29Z","timestamp":1768734329713,"version":"3.49.0"},"reference-count":39,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,8,7]],"date-time":"2022-08-07T00:00:00Z","timestamp":1659830400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union","award":["UIDB\/00081\/2020"],"award-info":[{"award-number":["UIDB\/00081\/2020"]}]},{"name":"European Union","award":["UIDP\/00081\/2020"],"award-info":[{"award-number":["UIDP\/00081\/2020"]}]},{"name":"European Union","award":["LA\/P\/0056\/2020"],"award-info":[{"award-number":["LA\/P\/0056\/2020"]}]},{"name":"CIQUP","award":["UIDB\/00081\/2020"],"award-info":[{"award-number":["UIDB\/00081\/2020"]}]},{"name":"CIQUP","award":["UIDP\/00081\/2020"],"award-info":[{"award-number":["UIDP\/00081\/2020"]}]},{"name":"CIQUP","award":["LA\/P\/0056\/2020"],"award-info":[{"award-number":["LA\/P\/0056\/2020"]}]},{"name":"IMS","award":["UIDB\/00081\/2020"],"award-info":[{"award-number":["UIDB\/00081\/2020"]}]},{"name":"IMS","award":["UIDP\/00081\/2020"],"award-info":[{"award-number":["UIDP\/00081\/2020"]}]},{"name":"IMS","award":["LA\/P\/0056\/2020"],"award-info":[{"award-number":["LA\/P\/0056\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Optosensing chitosan-based membranes have been applied for the detection of heavy metals, especially in drinking water. The novelty of this study is based on the use of sulphated polysaccharides, in such optosensing membranes, aiming at an improved analytical performance. The sulphated polysaccharides, such as ulvan, fucoidan and chondroitin sulfate, were extracted from by-products and wastes of marine-related activities. The membranes were developed for the analysis of aluminum. The variation in the visible absorbance of the sensor membranes after the contact between the chromophore and the aluminum cation was studied. The membranes containing sulphated polysaccharides showed improved signals when compared to the chitosan-only membrane. As for the detection limits for the membranes containing ulvan, fucoidan and chondroitin sulfate, 0.17 mg L\u22121, 0.21 mg L\u22121 and 0.36 mg L\u22121 were obtained, respectively. The values were much lower than that obtained for the chitosan-only membrane, 0.52 mg L\u22121, which shows the improvement obtained from the sulphated polysaccharides. The results were obtained with the presence of CTAB in analysis solution, which forms a ternary complex with the aluminum cation and the chromophore. This resulted in an hyperchromic and batochromic shift in the absorption band. When in the presence of this surfactant, the membranes showed lower detection limits and higher selectivity.<\/jats:p>","DOI":"10.3390\/molecules27155026","type":"journal-article","created":{"date-parts":[[2022,8,8]],"date-time":"2022-08-08T22:33:11Z","timestamp":1659997991000},"page":"5026","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Improved Metal Cation Optosensing Membranes through the Incorporation of Sulphated Polysaccharides"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5884-5311","authenticated-orcid":false,"given":"P. R. M.","family":"Santos","sequence":"first","affiliation":[{"name":"Research Center in Chemistry UP (CIQUP), Institute of Molecular Sciences (IMS); Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9278-4978","authenticated-orcid":false,"given":"A.","family":"Johny","sequence":"additional","affiliation":[{"name":"Research Center in Chemistry UP (CIQUP), Institute of Molecular Sciences (IMS); Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal"}]},{"given":"C. Q.","family":"Silva","sequence":"additional","affiliation":[{"name":"Research Center in Chemistry UP (CIQUP), Institute of Molecular Sciences (IMS); Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal"},{"name":"KAUST Catalysis Center, Catalysis Nanomaterials and Spectroscopy (CNS), King Abdullah University of Science and Technology, Thuwal 23955, Saudi Arabia"}]},{"given":"M. A.","family":"Azenha","sequence":"additional","affiliation":[{"name":"Research Center in Chemistry UP (CIQUP), Institute of Molecular Sciences (IMS); Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1122-4726","authenticated-orcid":false,"given":"J. A.","family":"V\u00e1zquez","sequence":"additional","affiliation":[{"name":"Grupo de Reciclado y Valorizaci\u00f3n de Materiales Residuales (REVAL), Instituto de Investigaciones Marinas (IIM-CSIC), C\/Eduardo Cabello, 6, 36208 Vigo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7336-4049","authenticated-orcid":false,"given":"J.","family":"Valcarcel","sequence":"additional","affiliation":[{"name":"Grupo de Reciclado y Valorizaci\u00f3n de Materiales Residuales (REVAL), Instituto de Investigaciones Marinas (IIM-CSIC), C\/Eduardo Cabello, 6, 36208 Vigo, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8392-9581","authenticated-orcid":false,"given":"C. M.","family":"Pereira","sequence":"additional","affiliation":[{"name":"Research Center in Chemistry UP (CIQUP), Institute of Molecular Sciences (IMS); Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal"}]},{"given":"A. F.","family":"Silva","sequence":"additional","affiliation":[{"name":"Research Center in Chemistry UP (CIQUP), Institute of Molecular Sciences (IMS); Departamento de Qu\u00edmica e Bioqu\u00edmica, Faculdade de Ci\u00eancias da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,7]]},"reference":[{"key":"ref_1","first-page":"411","article-title":"Chitin and chitosan: Production and application of versatile biomedical nanomaterials","volume":"4","author":"Hamblin","year":"2016","journal-title":"Int. J. Adv. Res."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"da Silva Alves, D.C., Healy, B., Pinto, L.A.d.A., Cadaval, T.R.S., and Breslin, C.B. (2021). Recent Developments in Chitosan-Based Adsorbents for the Removal of Pollutants from Aqueous Environments. Molecules, 26.","DOI":"10.3390\/molecules26030594"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1002\/pi.2378","article-title":"Main properties and current applications of some polysaccharides as biomaterials","volume":"57","author":"Rinaudo","year":"2008","journal-title":"Poly. Int."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Maliki, S., Sharma, G., Kumar, A., Moral-Zamorano, M., Moradi, O., Baselga, J., Stadler, F.J., and Garc\u00eda-Pe\u00f1as, A. (2022). Chitosan as a Tool for Sustainable Development: A Mini Review. Polymers, 14.","DOI":"10.3390\/polym14071475"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s40643-019-0243-y","article-title":"Seafood waste: A source for preparation of commercially employable chitin\/chitosan materials","volume":"6","author":"Yadav","year":"2019","journal-title":"Bioresour. Bioprocess."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1016\/j.reactfunctpolym.2017.04.001","article-title":"Preparation and evaluation of Pb(II)-imprinted fucoidan-based sorbents","volume":"115","author":"Ferreira","year":"2017","journal-title":"React. Funct. Polym."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"e2614","DOI":"10.1002\/jmr.2614","article-title":"Cationic imprinting of Pb (II) within composite networks based on bovine or fish chondroitin sulfate","volume":"31","author":"Ferreira","year":"2018","journal-title":"J. Mol. Recognit."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"172","DOI":"10.1016\/j.mtcomm.2016.08.003","article-title":"Metal cation sorption ability of immobilized and reticulated chondroitin sulfate or fucoidan through a sol-gel crosslinking scheme","volume":"8","author":"Ferreira","year":"2016","journal-title":"Mater. Today Commun."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"813","DOI":"10.1038\/pj.2014.70","article-title":"Urethane foam of sulphated polysaccharide ulvan derived from green-tide-forming chlorophyta: Synthesis and application in the removal of heavy metal ions from aqueous solutions","volume":"46","author":"Kanno","year":"2014","journal-title":"Poly. J."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1080\/10942912.2019.1573831","article-title":"Chemical characterization of sulphated polysaccharides from Gracilaria gracilis and Ulva lactuca and their radical scavenging, metal chelating, and cholinesterase inhibitory activities","volume":"22","author":"Olasehinde","year":"2019","journal-title":"Int. J. Food Prop."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.jwpe.2016.04.004","article-title":"Investigating film structure of membrane-based colorimetric sensor for heavy metal detection","volume":"15","author":"Azmi","year":"2017","journal-title":"J. Water Process Eng."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"772","DOI":"10.1016\/j.snb.2012.03.071","article-title":"An optical sensing film for the determination of Co(II) based on disodium-1-nitroso-2-naphthol-3,6-disulfonate immobilized in chitosan film","volume":"166\u2013167","author":"Sombatsri","year":"2012","journal-title":"Sens. Actuators, B"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"7","DOI":"10.22146\/ijc.23560","article-title":"Optical Sensor for the Determination of Lead(II) Based On Immobilization of Dithizone onto Chitosan-Silica Membrane","volume":"17","author":"Nur","year":"2017","journal-title":"Indones. J. Chem."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Azeman, N.H., Arsad, N., and Bakar, A.A.A. (2020). Polysaccharides as the Sensing Material for Metal Ion Detection-Based Optical Sensor Applications. Sensors, 20.","DOI":"10.3390\/s20143924"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"61","DOI":"10.3844\/ajeassp.2011.61.65","article-title":"Optical Properties of Crosslinked Chitosan Thin Film with Glutaraldehyde Using Surface Plasmon Resonance Technique","volume":"4","author":"Fen","year":"2011","journal-title":"Am. J. Eng. Appl. Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1016\/j.snb.2012.03.070","article-title":"Surface plasmon resonance optical sensor for detection of Pb2+ based on immobilized p-tert-butylcalix[4]arene-tetrakis in chitosan thin film as an active layer","volume":"171\u2013172","author":"Fen","year":"2012","journal-title":"Sens. Actuators B"},{"key":"ref_17","first-page":"99","article-title":"Immobilization of Tetrabutyl Thiuram Disulfide in Chitosan Thin Film for Sensing Zinc Ion Using Surface Plasmon Resonance Spectroscopy","volume":"25","author":"Fen","year":"2013","journal-title":"Sens. Mater."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"459","DOI":"10.1016\/j.snb.2014.01.074","article-title":"Highly sensitive SPR response of Au\/chitosan\/graphene oxide nanostructured thin films toward Pb (II) ions","volume":"195","author":"Lokman","year":"2014","journal-title":"Sens. Actuators B"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"105724","DOI":"10.1016\/j.optlastec.2019.105724","article-title":"Optical properties of chitosan\/hydroxyl-functionalized graphene quantum dots thin film for potential optical detection of ferric (III) ion","volume":"120","author":"Anas","year":"2019","journal-title":"Opt. Laser Technol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"802","DOI":"10.1016\/j.ijleo.2018.10.071","article-title":"Optical and surface plasmon resonance sensing properties for chitosan\/carboxyl-functionalized graphene quantum dots thin film","volume":"178","author":"Ramdzan","year":"2019","journal-title":"Optik"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Uygun, Z.O., Ertugrul Uygun, H.D., Ermis, N., and Canbay, E. (2015). Molecularly Imprinted Sensors \u2014 New Sensing Technologies. Biosensors-Micro and Nanoscale Applications, IntechOpen.","DOI":"10.5772\/60781"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1074","DOI":"10.1016\/j.ijbiomac.2018.12.264","article-title":"Development and characterization of antioxidant active packaging and intelligent Al3+-sensing films based on carboxymethyl chitosan and quercetin","volume":"126","author":"Bai","year":"2019","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2178","DOI":"10.1021\/acs.biomac.6b00399","article-title":"Chitosan\/Chondroitin Sulfate Membranes Produced by Polyelectrolyte Complexation for Cartilage Engineering","volume":"17","author":"Rodrigues","year":"2016","journal-title":"Biomacromolecules"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1016\/j.aca.2004.01.028","article-title":"Optical determination of ionophore diffusion coefficients in plasticized poly(vinyl chloride) sensing films","volume":"511","author":"Long","year":"2004","journal-title":"Anal. Chim. Acta"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"593","DOI":"10.1016\/j.foodhyd.2016.10.001","article-title":"Technology optimization of chitosan production from Aspergillus niger biomass and its functional activities","volume":"63","author":"Hifney","year":"2017","journal-title":"Food Hydrocoll."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1016\/j.foodhyd.2018.03.054","article-title":"Preparation of sulfur nanoparticle-incorporated antimicrobial chitosan films","volume":"82","author":"Shankar","year":"2018","journal-title":"Food Hydrocoll."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"433","DOI":"10.1021\/bm8012378","article-title":"Ion Pairing and Hydration in Polyelectrolyte Multilayer Films Containing Polysaccharides","volume":"10","author":"Crouzier","year":"2009","journal-title":"Biomacromolecules"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"280","DOI":"10.1016\/j.foodhyd.2014.03.007","article-title":"Isolation and antioxidant capacity of fucoidan from selected Malaysian seaweeds","volume":"42","author":"Lim","year":"2014","journal-title":"Food Hydrocoll."},{"key":"ref_29","first-page":"459","article-title":"Activated lignin and aminosilane- grafted silica as precursors in hybrid material production","volume":"52","author":"Klapiszewski","year":"2016","journal-title":"Physicochem. Probl. Miner. Process."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.polymdegradstab.2014.12.006","article-title":"Advanced physico-chemical characterization of chitosan by means of TGA coupled on-line with FTIR and GCMS: Thermal degradation and water adsorption capacity","volume":"112","author":"Corazzari","year":"2015","journal-title":"Polym. Degrad. Stab."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"305","DOI":"10.1016\/0003-2670(95)00497-1","article-title":"Equilibrium modelling of interferences in the visible spectrophotometric determination of aluminium(III): Comparison of the chromophores chrome azurol S, eriochrome cyanine R and pyrocatechol violet, and stability constants for eriochrome cyanine R-aluminium complexes","volume":"319","author":"Hawke","year":"1996","journal-title":"Anal. Chim. Acta"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1431","DOI":"10.1039\/an9820701431","article-title":"Formation of ternary complexes of aluminium with some triphenylmethane reagents and cationic surfactants","volume":"107","author":"Marczenko","year":"1982","journal-title":"Analyst"},{"key":"ref_33","first-page":"1154","article-title":"Quantitation of Aluminium Content in Waters and Soft Drinks by Spectrophotometry Using Erichrome Cyanine R","volume":"4","author":"Watsaka","year":"2013","journal-title":"Res. J. Pharm. Biol. Chem. Sci."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"642","DOI":"10.1016\/j.jhazmat.2007.06.037","article-title":"Selective and sensitive spectrophotometric method for determination of sub-micro-molar amounts of aluminium ion","volume":"151","author":"Shokrollahi","year":"2008","journal-title":"J. Hazard. Mater."},{"key":"ref_35","unstructured":"(2018). Pearson, Description of test kit for Eriochrome Cyanine R method 8326 for Aluminium, 9, Software Engineering Hach Company."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"565","DOI":"10.1039\/a708882e","article-title":"Unexpected complexation behaviour of a sol\u2013gel immobilised dye: The development of an optical copper(II) sensor","volume":"8","author":"Sommerdijk","year":"1998","journal-title":"J. Mater. Chem."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/j.carbpol.2016.09.050","article-title":"By-products of Scyliorhinus canicula, Prionace glauca and Raja clavata: A valuable source of predominantly 6S sulfated chondroitin sulfate","volume":"157","author":"Blanco","year":"2017","journal-title":"Carbohydr. Polym."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"V\u00e1zquez, J.A., Fraguas, J., Novoa-Carvallal, R., Reis, R.L., Antelo, L.T., P\u00e9rez-Mart\u00edn, R.I., and Valcarcel, J. (2018). Isolation and chemical characterization of chondroitin sulfate from cartilage by-products of blackmouth catshark (Galeus melastomus). Mar. Drugs, 16.","DOI":"10.3390\/md16100344"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"302","DOI":"10.1016\/j.carbpol.2019.01.075","article-title":"Optimal isolation and characterisation of chondroitin sulfate from rabbit fish (Chimaera monstrosa)","volume":"210","author":"Fraguas","year":"2019","journal-title":"Carbohydr. Polym."}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/27\/15\/5026\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:05:26Z","timestamp":1760141126000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/27\/15\/5026"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,8,7]]},"references-count":39,"journal-issue":{"issue":"15","published-online":{"date-parts":[[2022,8]]}},"alternative-id":["molecules27155026"],"URL":"https:\/\/doi.org\/10.3390\/molecules27155026","relation":{},"ISSN":["1420-3049"],"issn-type":[{"value":"1420-3049","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,8,7]]}}}