{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T16:01:28Z","timestamp":1785427288384,"version":"3.56.0"},"reference-count":51,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T00:00:00Z","timestamp":1785283200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["52104272"],"award-info":[{"award-number":["52104272"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["52104272"],"award-info":[{"award-number":["52104272"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Young Elite Scientists Sponsorship Program by CAST","award":["2024QNRC001"],"award-info":[{"award-number":["2024QNRC001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>It is crucial to develop advanced fluorescence sensing platforms for precise detection of metal pollutants in environmental monitoring. However, traditional fluorescent probes are often limited by aggregation-caused quenching (ACQ). In contrast, clusterization-triggered emission (CTE) probes, based on non-conjugated systems, exhibit excellent photostability by relying on spatial clusterization to restrict molecular motion. Crab shells, an abundant aquatic waste, are rich in chitin (20\u201330%). Following deacetylation, chitin is converted into chitosan, a biocompatible and biodegradable biopolymer with excellent potential for chemical modification. In this study, a novel chitosan-based CTE fluorescent probe (CS-FA) was synthesized via a facile cross-linking condensation reaction between chitosan and formaldehyde. This process successfully restricts intramolecular motion and promotes the tight clustering of electron-rich heteroatoms, thereby activating the CTE mechanism. The resultant CS-FA probe exhibits strong and stable blue fluorescence and demonstrates high selectivity and sensitivity toward Fe3+ in aqueous media. In the concentration range of 10\u2013100 \u00b5M, the fluorescence intensity decreases linearly with the Fe3+ concentration, yielding a competitive limit of detection (LOD) of 0.52 \u00b5M. Mechanistically, the specific coordination between Fe3+ and the cross-linked polymer provides a dominant non-radiative decay pathway, leading to significant fluorescence quenching. Ultimately, this work not only proposes an innovative strategy for constructing sensitive and biomass-derived probes for Fe3+ monitoring but also broadens the high-value utilization pathways of marine waste, thereby providing a sustainable waste-to-resource strategy.<\/jats:p>","DOI":"10.3390\/nano16150933","type":"journal-article","created":{"date-parts":[[2026,7,29]],"date-time":"2026-07-29T13:53:31Z","timestamp":1785333211000},"page":"933","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Sustainable Synthesis of Fe3+-Responsive Fluorescent Probes from Crab Shell Waste-Derived Chitosan"],"prefix":"10.3390","volume":"16","author":[{"given":"Yifan","family":"Ren","sequence":"first","affiliation":[{"name":"Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, Hebei Key Laboratory of Resource Low-Carbon Utilization and New Materials, School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jingnan","family":"Hu","sequence":"additional","affiliation":[{"name":"Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, Hebei Key Laboratory of Resource Low-Carbon Utilization and New Materials, School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huan","family":"Chen","sequence":"additional","affiliation":[{"name":"Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, Hebei Key Laboratory of Resource Low-Carbon Utilization and New Materials, School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yutong","family":"Ye","sequence":"additional","affiliation":[{"name":"Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, Hebei Key Laboratory of Resource Low-Carbon Utilization and New Materials, School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruiqi","family":"Zhang","sequence":"additional","affiliation":[{"name":"Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, Hebei Key Laboratory of Resource Low-Carbon Utilization and New Materials, School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1406-6057","authenticated-orcid":false,"given":"Ruiyu","family":"Mi","sequence":"additional","affiliation":[{"name":"Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, Hebei Key Laboratory of Resource Low-Carbon Utilization and New Materials, School of Materials Science and Technology, China University of Geosciences (Beijing), Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1925","DOI":"10.1016\/j.bbadis.2018.08.030","article-title":"Role of iron metabolism in heart failure: From iron deficiency to iron overload","volume":"1865","author":"Zhang","year":"2019","journal-title":"Biochim. 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