{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T12:04:32Z","timestamp":1784721872590,"version":"3.55.0"},"reference-count":38,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T00:00:00Z","timestamp":1784678400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2024YFF1105703"],"award-info":[{"award-number":["2024YFF1105703"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>Rapid and matrix\u2013aware evaluation of antioxidant responses in dairy\u2013containing tea beverages remains challenging because milk components may interfere with the detectable activity of tea polyphenols. In this study, a photoactivated Mn\u2013doped carbon nanosheet (Mn\u2013CNS)\u2013based dual\u2013mode nanozyme assay was developed for the rapid evaluation of antioxidant responses in tea beverages and dairy tea matrices. The Mn\u2013CNSs exhibited light\u2013triggered oxidase\u2013like activity toward 3,3\u2032,5,5\u2032\u2013tetramethylbenzidine, enabling synchronized colorimetric and fluorescence readouts within 1 min. Using epigallocatechin gallate as a model antioxidant, the assay showed limits of detection of 0.22 and 0.29 \u03bcg\/mL in the colorimetric and fluorescence modes, respectively, together with good selectivity and applicability to tea infusions. When applied to milk tea systems, the measurable antioxidant response decreased to 56.9\u201372.2% of that in corresponding tea infusions, indicating a pronounced matrix\u2013dependent attenuation. Matrix\u2013matched calibration and dual\u2013indicator recovery analysis further distinguished tea infusion recovery from antioxidant response recovery, while molecular docking suggested that \u03b2\u2013lactoglobulin\u2013EGCG interactions contributed to the reduced detectable response. These results demonstrate that the proposed dual\u2013mode assay is a rapid tool for antioxidant\u2013response evaluation and highlight the importance of matrix\u2013aware interpretation in complex dairy tea beverages.<\/jats:p>","DOI":"10.3390\/foods15142572","type":"journal-article","created":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T10:48:28Z","timestamp":1784717308000},"page":"2572","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Dual\u2013Mode Nanozyme Assay Based on Photoactivated Mn\u2013Doped Carbon Nanosheets for Rapid Evaluation of Antioxidant Responses in Tea Beverages and Dairy Tea Matrices"],"prefix":"10.3390","volume":"15","author":[{"given":"Qiongmeng","family":"Lu","sequence":"first","affiliation":[{"name":"School of Grain Science and Technology, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiuju","family":"He","sequence":"additional","affiliation":[{"name":"School of Grain Science and Technology, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiling","family":"Fang","sequence":"additional","affiliation":[{"name":"School of Grain Science and Technology, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zheng","family":"Wei","sequence":"additional","affiliation":[{"name":"School of Grain Science and Technology, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4804-1501","authenticated-orcid":false,"given":"Qi","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Grain Science and Technology, Jiangsu University of Science and Technology, Zhenjiang 212100, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5048-0688","authenticated-orcid":false,"given":"Yaxiong","family":"Song","sequence":"additional","affiliation":[{"name":"Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University, Tianjin 300071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2974-329X","authenticated-orcid":false,"given":"Shijie","family":"Li","sequence":"additional","affiliation":[{"name":"School of Grain Science and Technology, Jiangsu University of Science and Technology, Zhenjiang 212100, China"},{"name":"Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University, Tianjin 300071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuo","family":"Wang","sequence":"additional","affiliation":[{"name":"Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University, Tianjin 300071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Nhu-Trang, T.-T., Nguyen, Q.-D., Cong-Hau, N., Anh-Dao, L.-T., and Behra, P. 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