{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T05:16:47Z","timestamp":1788239807278,"version":"build-2803163510"},"reference-count":41,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T00:00:00Z","timestamp":1787788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>Laccases are multicopper oxidases capable of oxidizing a wide range of substrates using molecular oxygen as the terminal electron acceptor, producing water as the sole by-product. High-redox potential fungal laccases, such as those from Trametes versicolor, are particularly attractive for industrial and environmental applications, although their use is often limited by sensitivity to operational conditions. Enzyme immobilization represents an effective strategy to enhance laccase stability and reusability. In this work, magnetic nanoparticles (MNPs) were investigated as support for laccase immobilization due to their high surface area, biocompatibility, and ease of magnetic recovery. Two modified co-precipitation synthetic routes were systematically evaluated, and the size, morphology, and chemical composition of the products were characterized by microscopy, light scattering, and spectroscopic methods, while both adsorption and covalent immobilization strategies were explored. The MNP surface was found to be highly reactive toward radical species generated during laccase-catalyzed reactions, especially in the presence of small Fe2+ excess. While this can enhance the enzyme catalytic activity, it challenges the inertness of the support and promotes, in some cases, strong interactions between reaction products and the nanoparticle surface. These findings highlight a previously unexplored role of magnetic supports in laccase-based biocatalytic systems.<\/jats:p>","DOI":"10.3390\/biom16091244","type":"journal-article","created":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T16:47:13Z","timestamp":1787849233000},"page":"1244","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Unveiling the Physicochemical Properties of Magnetic Nanoparticles as Solid Carriers for Laccase Immobilization Toward Different Reducing Substrates"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7840-2267","authenticated-orcid":false,"given":"Jessica","family":"Costa","sequence":"first","affiliation":[{"name":"Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2969-546X","authenticated-orcid":false,"given":"Andrea","family":"Atrei","sequence":"additional","affiliation":[{"name":"Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4808-1730","authenticated-orcid":false,"given":"Juan Jos\u00e9","family":"Valle-Delgado","sequence":"additional","affiliation":[{"name":"Department of Bioproducts and Biosystems, Aalto University, Vuorimiehentie 1, 02150 Espoo, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3558-9172","authenticated-orcid":false,"given":"Monika","family":"\u00d6sterberg","sequence":"additional","affiliation":[{"name":"Department of Bioproducts and Biosystems, Aalto University, Vuorimiehentie 1, 02150 Espoo, Finland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6681-1592","authenticated-orcid":false,"given":"Rebecca","family":"Pogni","sequence":"additional","affiliation":[{"name":"Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Wang, H., Tang, L.X., Ye, Y.F., Ma, J.X., Li, X., Si, J., and Cui, B.K. (2024). Laccase Immobilization and Its Degradation of Emerging Pollutants: A Comprehensive Review. J. Environ. Manag., 359.","DOI":"10.1016\/j.jenvman.2024.120984"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"801","DOI":"10.1021\/acs.chemrev.7b00203","article-title":"Role of Biocatalysis in Sustainable Chemistry","volume":"118","author":"Sheldon","year":"2018","journal-title":"Chem. Rev."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"438","DOI":"10.1016\/S0958-1669(03)00099-5","article-title":"Directed Evolution of Industrial Enzymes: An Update","volume":"14","author":"Cherry","year":"2003","journal-title":"Curr. Opin. Biotechnol."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Chapman, J., Ismail, A.E., and Dinu, C.Z. (2018). Industrial Applications of Enzymes: Recent Advances, Techniques, and Outlooks. Catalysts, 8.","DOI":"10.3390\/catal8060238"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"5102","DOI":"10.15376\/biores.12.3.5102-5117","article-title":"Effect of Common Metal Ions and Anions on Laccase Catalysis of Guaiacol and Lignocellulosic Fiber","volume":"12","author":"Zhou","year":"2017","journal-title":"BioResources"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"6223","DOI":"10.1039\/C3CS60075K","article-title":"Enzyme Immobilisation in Biocatalysis: Why, What and How","volume":"42","author":"Sheldon","year":"2013","journal-title":"Chem. Soc. Rev."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Basso, A., and Serban, S. (2019). Industrial Applications of Immobilized Enzymes\u2014A Review. Mol. Catal., 479.","DOI":"10.1016\/j.mcat.2019.110607"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"6437","DOI":"10.1039\/c3cs35506c","article-title":"Industrial Use of Immobilized Enzymes","volume":"42","author":"Poulose","year":"2013","journal-title":"Chem. Soc. Rev."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Zdarta, J., Meyer, A.S., Jesionowski, T., and Pinelo, M. (2018). A General Overview of Support Materials for Enzyme Immobilization: Characteristics, Properties, Practical Utility. Catalysts, 8.","DOI":"10.3390\/catal8020092"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2530","DOI":"10.1016\/j.ijbiomac.2018.09.025","article-title":"Magnetic Nanoparticles as Versatile Carriers for Enzymes Immobilization: A Review","volume":"120","author":"Bilal","year":"2018","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1155\/2012\/614094","article-title":"Biocompatibility and Toxicity of Magnetic Nanoparticles in Regenerative Medicine","volume":"2012","author":"Markides","year":"2012","journal-title":"J. Nanomater."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"He, G., Liu, H., Yang, C., Hu, K., Zhai, X., Fang, B., Liu, K., and Li, D. (2024). A Comparison of Dual-Enzyme Immobilization by Magnetic Nanoparticles and Magnetic Enzyme Aggregates for Cascade Enzyme Reactions. Biochem. Eng. J., 204.","DOI":"10.1016\/j.bej.2023.109207"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"5529","DOI":"10.1039\/D0RA10409D","article-title":"Production and Characterization of Chitooligosaccharides by the Fungal Chitinase Chit42 Immobilized on Magnetic Nanoparticles and Chitosan Beads: Selectivity, Specificity and Improved Operational Utility","volume":"11","author":"Kidibule","year":"2021","journal-title":"RSC Adv."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Wang, B., Bian, C., Lu, X., Ma, Y., Li, N., Xiong, D., Xu, X., Yang, Z., Zhang, H., and Guan, T. (2025). Laccase Immobilized on Magnetic Nanoparticles for the Degradation of Imidacloprid: Based on Multi-Spectroscopy and Molecular Docking. Spectrochim. Acta A Mol. Biomol. Spectrosc., 333.","DOI":"10.1016\/j.saa.2025.125888"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1016\/B978-0-443-13301-5.00005-6","article-title":"Reaction Mechanism and Redox Potential of Laccase","volume":"72","author":"Sharma","year":"2025","journal-title":"Laccase and Polyphenol Oxidase: Biochemistry and Biotechnological Applications"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Pomogailo, S.I., Chepaikin, E.G., Bubelo, O.N., Jussupkaliyeva, R.I., and Kustov, L.M. (2024). Magnetic Nanocomposites Based on Iron Oxides as Catalysts of Oxidation Reactions. Crystals, 14.","DOI":"10.3390\/cryst14121031"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Atrei, A., Mahdizadeh, F.F., Baratto, M.C., and Scala, A. (2021). Effect of Citrate on the Size and the Magnetic Properties of Primary Fe3o4 Nanoparticles and Their Aggregates. Appl. Sci., 11.","DOI":"10.3390\/app11156974"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Atrei, A., Lesiak-Orlowska, B., and T\u00f3th, J. (2022). Magnetite nanoparticles functionalized with citrate: A surface science study by XPS and ToF-SIMS. Appl. Surf. Sci., 602.","DOI":"10.1016\/j.apsusc.2022.154366"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5436","DOI":"10.1021\/jp311556b","article-title":"Stability and Relaxation Mechanisms of Citric Acid Coated Magnetite Nanoparticles for Magnetic Hyperthermia","volume":"117","author":"Rivas","year":"2013","journal-title":"J. Phys. Chem. C"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1016\/j.cej.2015.10.083","article-title":"Enhancement of the Catalytic Activity and Stability of Immobilized Aminoacylase Using Modified Magnetic Fe3O4 Nanoparticles","volume":"286","author":"Feng","year":"2016","journal-title":"Chem. Eng. J."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1016\/j.molcatb.2009.12.018","article-title":"Synthesis and Structural Characterization of a Novel Phenoxazinone Dye by Use of a Fungal Laccase","volume":"63","author":"Forte","year":"2010","journal-title":"J. Mol. Catal. B Enzym."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1088\/1742-6596\/1013\/1\/012190","article-title":"The Impact of Synthesis Temperature on Magnetite Nanoparticles Size Synthesized by Co-Precipitation Method","volume":"1013","author":"Saragi","year":"2018","journal-title":"J. Phys. Conf. Ser."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"19178","DOI":"10.1021\/jp803832k","article-title":"Optimization of the Synthesis of Superparamagnetic Contrast Agents by the Design of Experiments Method","volume":"112","author":"Forge","year":"2008","journal-title":"J. Phys. Chem. C"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Schwaminger, S.P., Syhr, C., and Berensmeier, S. (2020). Controlled Synthesis of Magnetic Iron Oxide Nanoparticles: Magnetite or Maghemite?. Crystals, 10.","DOI":"10.3390\/cryst10030214"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1016\/j.jmmm.2006.05.001","article-title":"Synthesis of Iron Oxide Nanoparticles under Oxidizing Environment and Their Stabilization in Aqueous and Non-Aqueous Media","volume":"308","author":"Maity","year":"2007","journal-title":"J. Magn. Magn. Mater."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1591","DOI":"10.1002\/ceat.200800093","article-title":"Phase Transformation of Iron Oxide Nanoparticles by Varying the Molar Ratio of Fe2+:Fe3+","volume":"31","author":"Alibeigi","year":"2008","journal-title":"Chem. Eng. Technol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1016\/j.dyepig.2004.08.016","article-title":"Synthesis and Characterization of Magnetic Nanometer Pigment Fe3O4","volume":"66","author":"Meng","year":"2005","journal-title":"Dye. Pigment."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Zhang, J., Lin, S., Meiling, H., Qing, S., and Liancu, X. (2020). Adsorption Properties of Magnetic Magnetite. Water, 12.","DOI":"10.3390\/w12020446"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Jain, R., and Gulati, S. (2023). Influence of Fe2+ Substitution on FTIR and Raman Spectra of Mn Ferrite Nanoparticles. Vib. Spectrosc., 126.","DOI":"10.1016\/j.vibspec.2023.103540"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"14139","DOI":"10.3390\/molecules190914139","article-title":"Inorganic Materials as Supports for Covalent Enzyme Immobilization: Methods and Mechanisms","volume":"19","author":"Zucca","year":"2014","journal-title":"Molecules"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"7284","DOI":"10.1039\/b812096j","article-title":"Characterization of Radical Intermediates in Laccase-Mediator Systems. a Multifrequency EPR, ENDOR and DFT\/PCM Investigation","volume":"10","author":"Brogioni","year":"2008","journal-title":"Phys. Chem. Chem. Phys."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"5471961","DOI":"10.1155\/2018\/5471961","article-title":"Immobilization of a Laccase\/2,2\u2032-Azino-Bis-(3-Ethylbenzothiazoline)-6-Sulfonic Acid System to Layered Double Hydroxide\/Alginate Biohybrid Beads for Biodegradation of Malachite Green Dye","volume":"2018","author":"Huang","year":"2018","journal-title":"BioMed Res. Int."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Othman, A.M., and Flaifil, A.G. (2025). Characterization and Evaluation of the Immobilized Laccase Enzyme Potential in Dye Degradation via One Factor and Response Surface Methodology Approaches. Sci. Rep., 15.","DOI":"10.1038\/s41598-024-82310-0"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1098","DOI":"10.1016\/j.ijbiomac.2019.10.198","article-title":"A Novel Method for Improving Laccase Activity by Immobilization onto Copper Ferrite Nanoparticles for Lignin Degradation","volume":"152","author":"Muthuvelu","year":"2020","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"605","DOI":"10.1007\/s00253-009-1869-z","article-title":"Fungal Laccases as Tools for the Synthesis of New Hybrid Molecules and Biomaterials","volume":"82","author":"Mikolasch","year":"2009","journal-title":"Appl. Microbiol. Biotechnol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"575","DOI":"10.1002\/adsc.201701228","article-title":"A Sustainable Synthesis of Asymmetric Phenazines and Phenoxazinones Mediated by CotA-Laccase","volume":"360","author":"Sousa","year":"2018","journal-title":"Adv. Synth. Catal."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"4127","DOI":"10.1039\/C4GC00901K","article-title":"Towards the Rational Biosynthesis of Substituted Phenazines and Phenoxazinones by Laccases","volume":"16","author":"Sousa","year":"2014","journal-title":"Green Chem."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Wliz\u0142o, K., Polak, J., Jarosz-Wilko\u0142azka, A., Pogni, R., and Petricci, E. (2020). Novel Textile Dye Obtained through Transformation of 2-Amino-3-Methoxybenzoic Acid by Free and Immobilised Laccase from a Pleurotus Ostreatus Strain. Enzym. Microb. Technol., 132.","DOI":"10.1016\/j.enzmictec.2019.109398"},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Costa, J., Baratto, M.C., Spinelli, D., Leone, G., Magnani, A., and Pogni, R. (2024). A Novel Bio-Adhesive Based on Chitosan-Polydopamine-Xanthan Gum for Glass, Cardboard and Textile Commodities. Polymers, 16.","DOI":"10.2139\/ssrn.4830076"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Zou, Y., Chen, X., Yang, P., Liang, G., Yang, Y., Gu, Z., and Li, Y. (2020). Regulating the Absorption Spectrum of Polydopamine. Sci. Adv., 6.","DOI":"10.1126\/sciadv.abb4696"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/j.molcatb.2014.11.012","article-title":"High Catalytic Activity of Immobilized Laccase on Core\u2013Shell Magnetic Nanoparticles by Dopamine Self-Polymerization","volume":"112","author":"Deng","year":"2015","journal-title":"J. Mol. Catal. B Enzym."}],"container-title":["Biomolecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2218-273X\/16\/9\/1244\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T04:25:43Z","timestamp":1788236743000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2218-273X\/16\/9\/1244"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,27]]},"references-count":41,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["biom16091244"],"URL":"https:\/\/doi.org\/10.3390\/biom16091244","relation":{},"ISSN":["2218-273X"],"issn-type":[{"value":"2218-273X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,27]]}}}