{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T12:13:21Z","timestamp":1785413601712,"version":"3.56.0"},"reference-count":44,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T00:00:00Z","timestamp":1777593600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100011302","name":"State Key Laboratory of Advanced Technology For Materials Synthesis and Processing","doi-asserted-by":"publisher","award":["WUT:2025-ZD-4"],"award-info":[{"award-number":["WUT:2025-ZD-4"]}],"id":[{"id":"10.13039\/501100011302","id-type":"DOI","asserted-by":"publisher"}]},{"award":["WUT:2025-ZD-4"],"award-info":[{"award-number":["WUT:2025-ZD-4"]}],"id":[{"id":"https:\/\/ror.org\/05njhbf68","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["51573144"],"award-info":[{"award-number":["51573144"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"award":["51573144"],"award-info":[{"award-number":["51573144"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Innovation Team in Key Areas of the Innovation Talent Promotion Plan (2021) of MOST"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Magnetic photonic crystal microspheres (MPCMs) have emerged as a versatile platform for intelligent sensing and display applications, owing to their integration of magnetic actuation with structural coloration. However, their practical implementation is limited by a fundamental structural constraint: most reported MPCMs adopt anisotropic architectures, resulting in angle-dependent optical responses that require continuous magnetic alignment to maintain uniform coloration. Herein, we propose a different structural paradigm based on non-close-packed, optically isotropic MPCMs. Driven by electrostatic repulsion in solutions, monodisperse Fe3O4@tannic acid (TA) core\u2013shell nanoparticles spontaneously assemble into non-close-packed amorphous colloidal arrays, also known as photonic glasses, which are subsequently immobilized within stimuli-responsive polymer networks via emulsification-assisted thermal polymerization. By integrating poly(2-hydroxyethyl methacrylate-co-N-vinylpyrrolidone) (HEMA\u2013NVP) or poly(N-isopropylacrylamide) (PNIPAM) as responsive matrices, the resulting MPCMs exhibit sensitive solvent- or thermo-dependent optical responses. Crucially, structural isotropy ensures angle-independent coloration, eliminating the need for continuous magnetic alignment during optical readout. As evidenced by the unchanged structural color and reflection peak under various magnetic field orientations, this design effectively decouples optical sensing from magnetic actuation. The intrinsic free volume of the non-close-packed architecture allows for isotropic lattice expansion and contraction, leading to broad spectral tunability. Collectively, this work establishes a promising design framework for magnetic photonic microsensors.<\/jats:p>","DOI":"10.3390\/nano16090556","type":"journal-article","created":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T09:33:17Z","timestamp":1777627997000},"page":"556","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Non-Close-Packed Isotropic Responsive Magnetic Photonic Crystal Microspheres"],"prefix":"10.3390","volume":"16","author":[{"given":"Lejian","family":"Zhao","sequence":"first","affiliation":[{"name":"State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, International School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Zhu","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maocheng","family":"Sun","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Luo","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huiru","family":"Ma","sequence":"additional","affiliation":[{"name":"School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2223-4524","authenticated-orcid":false,"given":"Jianguo","family":"Guan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, International School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China"},{"name":"Wuhan Institute of Photochemistry and Technology, 7 North Bingang Road, Wuhan 430083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2059","DOI":"10.1103\/PhysRevLett.58.2059","article-title":"Inhibited Spontaneous Emission in Solid-State Physics and Electronics","volume":"58","author":"Yablonovitch","year":"1987","journal-title":"Phys. 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