{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,9]],"date-time":"2026-08-09T04:42:10Z","timestamp":1786250530866,"version":"build-2736575974"},"reference-count":47,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T00:00:00Z","timestamp":1786060800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003716","name":"Korea Basic Science Institute","doi-asserted-by":"crossref","award":["2019R1A6C1010033"],"award-info":[{"award-number":["2019R1A6C1010033"]}],"id":[{"id":"10.13039\/501100003716","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100003716","name":"Korea Basic Science Institute","doi-asserted-by":"crossref","award":["RS-2026-25539507"],"award-info":[{"award-number":["RS-2026-25539507"]}],"id":[{"id":"10.13039\/501100003716","id-type":"DOI","asserted-by":"crossref"}]},{"award":["2019R1A6C1010033"],"award-info":[{"award-number":["2019R1A6C1010033"]}],"id":[{"id":"https:\/\/ror.org\/0417sdw47","id-type":"ROR","asserted-by":"publisher"}]},{"award":["RS-2026-25539507"],"award-info":[{"award-number":["RS-2026-25539507"]}],"id":[{"id":"https:\/\/ror.org\/0417sdw47","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Institute of Information & Communications Technology Planning & Evaluation","award":["IITP-2026-RS-2024-00436765"],"award-info":[{"award-number":["IITP-2026-RS-2024-00436765"]}]},{"award":["IITP-2026-RS-2024-00436765"],"award-info":[{"award-number":["IITP-2026-RS-2024-00436765"]}],"id":[{"id":"https:\/\/ror.org\/01g0hqq23","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Hydrophilic osmium(Os)-based redox polymers were designed as electron-transfer mediators for fungal flavin adenine dinucleotide-dependent glucose dehydrogenase (FAD-GDH)-based glucose sensors. Poly(vinylimidazole-co-hydroxyethyl acrylate) (PVI-HEA) copolymers with different HEA compositions were synthesized and coordinated with Os(dmo-bpy)2Cl2 to prepare PVI-HEA-Os(dmo-bpy)2Cl2 redox mediators. The synthesized mediator systems were characterized using 1H-nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, ultraviolet\u2013visible spectroscopy, field emission scanning electron microscopy\/energy dispersive spectroscopy, zeta potential analysis, cyclic voltammetry, and electrochemical impedance spectroscopy. The results confirmed the successful formation of Os redox polymer structures and their immobilization on the electrode surface. The electrochemical behavior and glucose sensing performance strongly depended on the PVI-HEA composition. Among the compositions tested, PVI-HEA(3.5:1)-Os(dmo-bpy)2Cl2 showed the strongest redox current response, stable aqueous dispersion behavior, and relatively low interfacial charge-transfer resistance. Glucose-sensing measurements using FAD-GDH\/mediator-modified electrodes showed linear current responses over the glucose concentration range of 1.25\u201320 mM. The PVI-HEA(3.5:1)-Os(dmo-bpy)2Cl2-based electrode showed the highest sensitivity of 16.18 \u03bcA cm\u22122 mM\u22121, which was significantly higher than those observed at lower-HEA compositions. The optimized mediator system also showed selective glucose responses against representative biological interferents, including ascorbic acid, uric acid, dopamine, and serotonin. Stable catalytic current responses were maintained under Human Plasma-Like Medium conditions, suggesting improved matrix tolerance compared to conventional PVI-based Os redox polymers. The improved sensing performance was attributed to the hydrophilic polymer environment introduced by the HEA units, which may facilitate favorable interfacial charge-transfer behavior within the enzyme\u2013mediator layer. The results show that the hydrophilic copolymer composition plays an important role in the electrochemical behavior and glucose sensing performance of Os redox polymer mediators. The proposed PVI-HEA-Os(dmo-bpy)2Cl2 system may be a promising candidate for future enzymatic glucose sensing and continuous glucose monitoring-related applications.<\/jats:p>","DOI":"10.3390\/bios16080430","type":"journal-article","created":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T11:44:53Z","timestamp":1786103093000},"page":"430","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Hydrophilic PVI-HEA-Based Osmium Redox Polymers for Enhanced Electrochemical Glucose Sensing"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-5559-5069","authenticated-orcid":false,"given":"Tae-Won","family":"Seo","sequence":"first","affiliation":[{"name":"Department of Chemistry, College of Science and Technology, Dankook University, Cheonan 31116, Chungcheongnam-do, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Won-Yong","family":"Jeon","sequence":"additional","affiliation":[{"name":"Graduate School of Management of Technology, Hoseo University, 20 Hoseo-ro 79 beon-gil, Baebang-eup, Asan-si 31499, Chungcheongnam-do, Republic of Korea"},{"name":"Fine Dust & Net Zero Research Institute, Hoseo University, 20 Hoseo-ro 79 beon-gil, Baebang-eup, Asan-si 31499, Chungcheongnam-do, Republic of Korea"},{"name":"Eco Upcycling R&D Center, Hoseo University, 20 Hoseo-ro 79 beon-gil, Baebang-eup, Asan-si 31499, Chungcheongnam-do, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyug-Han","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemistry, College of Science and Technology, Dankook University, Cheonan 31116, Chungcheongnam-do, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3862-456X","authenticated-orcid":false,"given":"Young-Bong","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Chemistry, College of Science and Technology, Dankook University, Cheonan 31116, Chungcheongnam-do, Republic of Korea"},{"name":"Department of Cosmedical Materials, College of Bio-Convergence, Dankook University, Cheonan-si 31116, Chungcheongnam-do, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"107843","DOI":"10.1016\/j.diabres.2019.107843","article-title":"Global and regional diabetes prevalence estimates for 2019 and projections for 2030 and 2045: Results from the International Diabetes Federation Diabetes Atlas, 9th edition","volume":"157","author":"Saeedi","year":"2019","journal-title":"Diabetes Res. Clin. Pract."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1593","DOI":"10.2337\/dci19-0028","article-title":"Clinical targets for continuous glucose monitoring data interpretation: Recommendations from the international consensus on time in range","volume":"42","author":"Battelino","year":"2019","journal-title":"Diabetes Care"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"383","DOI":"10.4093\/dmj.2019.0121","article-title":"Continuous glucose monitoring sensors for diabetes management: A review of technologies and applications","volume":"43","author":"Cappon","year":"2019","journal-title":"Diabetes Metab. J."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Zafar, H., Channa, A., Jeoti, V., and Stojanovi\u0107, G.M. (2022). Comprehensive review on wearable sweat-glucose sensors for continuous glucose monitoring. Sensors, 22.","DOI":"10.3390\/s22020638"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"7854","DOI":"10.1021\/acs.chemrev.3c00078","article-title":"Wearable electrochemical glucose sensors in diabetes management: A comprehensive review","volume":"123","author":"Saha","year":"2023","journal-title":"Chem. Rev."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"893","DOI":"10.1039\/D4SD00086B","article-title":"Advances in electrochemical sensors for real-time glucose monitoring","volume":"3","author":"Aktar","year":"2024","journal-title":"Sens. Diagn."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Wang, M., Zheng, J., Zhang, G., Lu, S., and Zhou, J. (2025). Wearable electrochemical glucose sensors for fluid monitoring: Advances and challenges in non-invasive and minimally invasive technologies. Biosensors, 15.","DOI":"10.3390\/bios15050309"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"814","DOI":"10.1021\/cr068123a","article-title":"Electrochemical glucose biosensors","volume":"108","author":"Wang","year":"2008","journal-title":"Chem. Rev."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2482","DOI":"10.1021\/cr068069y","article-title":"Electrochemical glucose sensors and their applications in diabetes management","volume":"108","author":"Heller","year":"2008","journal-title":"Chem. Rev."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"7671","DOI":"10.1039\/D0CS00304B","article-title":"Electrochemical glucose sensors in diabetes management: An updated review (2010\u20132020)","volume":"49","author":"Teymourian","year":"2020","journal-title":"Chem. Soc. Rev."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1111\/j.1749-6632.1962.tb13623.x","article-title":"Electrode systems for continuous monitoring in cardiovascular surgery","volume":"102","author":"Clark","year":"1962","journal-title":"Ann. N. Y. Acad. Sci."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1068","DOI":"10.1177\/193229681100500507","article-title":"Review of glucose oxidases and glucose dehydrogenases: A bird\u2019s eye view of glucose sensing enzymes","volume":"5","author":"Ferri","year":"2011","journal-title":"J. Diabetes Sci. Technol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"107414","DOI":"10.1016\/j.bioelechem.2019.107414","article-title":"FAD dependent glucose dehydrogenases: Discovery and engineering of representative glucose sensing enzymes","volume":"132","author":"Yoshida","year":"2020","journal-title":"Bioelectrochemistry"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1016\/j.coelec.2018.06.003","article-title":"Enzyme based amperometric biosensors","volume":"10","author":"Bollella","year":"2018","journal-title":"Curr. Opin. Electrochem."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Bollella, P., and Katz, E. (2020). Enzyme-based biosensors: Tackling electron transfer issues. Sensors, 20.","DOI":"10.3390\/s20123517"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Kilic, N.M., Singh, S., Keles, G., Cinti, S., Kurbanoglu, S., and Odaci, D. (2023). Novel approaches to enzyme-based electrochemical nanobiosensors. Biosensors, 13.","DOI":"10.3390\/bios13060622"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Jamshidnejad-Tosaramandani, T., Kashanian, S., Omidfar, K., and Schi\u00f6th, H.B. (2025). The role of nanomaterials in the wearable electrochemical glucose biosensors for diabetes management. Biosensors, 15.","DOI":"10.3390\/bios15070451"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"115942","DOI":"10.1016\/j.bios.2023.115942","article-title":"Highly stable glucose oxidase polynanogel@MXene\/chitosan electrochemical biosensor based on a multi-stable interface structure for glucose detection","volume":"248","author":"Tong","year":"2024","journal-title":"Biosens. Bioelectron."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1285","DOI":"10.1021\/j100290a001","article-title":"Direct electrical communication between chemically modified enzymes and metal electrodes. I. Electron transfer from glucose oxidase to metal electrodes via electron relays, bound covalently to the enzyme","volume":"91","author":"Degani","year":"1987","journal-title":"J. Phys. Chem."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0003-2670(01)95447-9","article-title":"Mediator compounds for the electrochemical study of biological redox systems: A compilation","volume":"140","author":"Fultz","year":"1982","journal-title":"Anal. Chim. Acta"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"4473","DOI":"10.1039\/c2ra22351a","article-title":"Recent advances in electrochemical glucose biosensors: A review","volume":"3","author":"Chen","year":"2013","journal-title":"RSC Adv."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"128","DOI":"10.1021\/ar00173a002","article-title":"Electrical wiring of redox enzymes","volume":"23","author":"Heller","year":"1990","journal-title":"Acc. Chem. Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1021\/ac00202a007","article-title":"Cross-linked redox gels containing glucose oxidase for amperometric biosensor applications","volume":"62","author":"Gregg","year":"1990","journal-title":"Anal. Chem."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"3512","DOI":"10.1021\/ac00071a031","article-title":"Glucose electrodes based on cross-linked [Os(bpy)2Cl]+\/2+ complexed poly(1-vinylimidazole) films","volume":"65","author":"Ohara","year":"1993","journal-title":"Anal. Chem."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2451","DOI":"10.1021\/ac00087a008","article-title":"Wired enzyme electrodes for amperometric determination of glucose or lactate in the presence of interfering substances","volume":"66","author":"Ohara","year":"1994","journal-title":"Anal. Chem."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2268","DOI":"10.1021\/ac00020a014","article-title":"Amperometric glucose microelectrodes prepared through immobilization of glucose oxidase in redox hydrogels","volume":"63","author":"Pishko","year":"1991","journal-title":"Anal. Chem."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"4951","DOI":"10.1021\/ja029510e","article-title":"Long tethers binding redox centers to polymer backbones enhance electron transport in enzyme wiring hydrogels","volume":"125","author":"Mao","year":"2003","journal-title":"J. Am. Chem. Soc."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"664","DOI":"10.1016\/j.cbpa.2006.09.018","article-title":"Electron-conducting redox hydrogels: Design, characteristics and synthesis","volume":"10","author":"Heller","year":"2006","journal-title":"Curr. Opin. Chem. Biol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"137845","DOI":"10.1016\/j.electacta.2021.137845","article-title":"Electrochemical glucose biosensor based on an osmium redox polymer and glucose oxidase grafted to carbon nanotubes: A design-of-experiments optimisation of current density and stability","volume":"371","author":"Jayakumar","year":"2021","journal-title":"Electrochim. Acta"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Navarro-Nateras, L., Diaz-Gonzalez, J., Aguas-Chantes, D., Coria-Oriundo, L.L., Battaglini, F., Ventura-Gallegos, J.L., Zentella-Dehesa, A., Oza, G., Arriaga, L.G., and Casanova-Moreno, J.R. (2023). Development of a redox-polymer-based electrochemical glucose biosensor suitable for integration in microfluidic 3D cell culture systems. Biosensors, 13.","DOI":"10.3390\/bios13060582"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1016\/j.ymeth.2026.04.007","article-title":"Low-potential osmium-based PVI redox polymer mediators for diffusion-controlled electrochemical glucose quantification","volume":"251","author":"Chung","year":"2026","journal-title":"Methods"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Cho, Y.Y., Seo, T.-W., Choi, Y.-B., and Jeon, W.-Y. (2025). Enhanced solubility and electron transfer of osmium-based mediators via quaternized poly(4-vinylpyridine) for electrochemical glucose detection. Polymers, 17.","DOI":"10.3390\/polym17212874"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Seo, T.-W., Jeon, W.-Y., and Choi, Y.-B. (2023). Enhanced modification between glucose dehydrogenase and mediator using epoxy silane assembly for monitoring glucose. Chemosensors, 11.","DOI":"10.3390\/chemosensors11090485"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"487","DOI":"10.1038\/nature02388","article-title":"Designing materials for biology and medicine","volume":"428","author":"Langer","year":"2004","journal-title":"Nature"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1016\/j.addr.2012.09.010","article-title":"Hydrogels for biomedical applications","volume":"64","author":"Hoffman","year":"2012","journal-title":"Adv. Drug Deliv. Rev."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1016\/j.addr.2012.09.009","article-title":"Novel crosslinking methods to design hydrogels","volume":"64","author":"Hennink","year":"2012","journal-title":"Adv. Drug Deliv. Rev."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Mavronasou, K., Zamboulis, A., Klonos, P., Kyritsis, A., Bikiaris, D.N., Papadakis, R., and Deligkiozi, I. (2022). Poly(vinyl pyridine) and its quaternized derivatives: Understanding their solvation and solid-state properties. Polymers, 14.","DOI":"10.3390\/polym14040804"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1354","DOI":"10.1021\/acs.macromol.8b01661","article-title":"Poly(vinylpyridine) segments in block copolymers: Synthesis, self-assembly, and versatility","volume":"52","author":"Kennemur","year":"2019","journal-title":"Macromolecules"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1016\/S0022-0728(79)80075-3","article-title":"General expression of the linear potential sweep voltammogram in the case of diffusionless electrochemical systems","volume":"101","author":"Laviron","year":"1979","journal-title":"J. Electroanal. Chem. Interfacial Electrochem."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1039\/TF9484400327","article-title":"A cathode ray polarograph. Part II. The current-voltage curves","volume":"44","author":"Randles","year":"1948","journal-title":"Trans. Faraday Soc."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1351","DOI":"10.1021\/ac60230a016","article-title":"Theory and application of cyclic voltammetry for measurement of electrode reaction kinetics","volume":"37","author":"Nicholson","year":"1965","journal-title":"Anal. Chem."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"e202103084","DOI":"10.1002\/slct.202103084","article-title":"Revisiting zeta potential, the key feature of interfacial phenomena, with applications and recent advancements","volume":"7","author":"Kamble","year":"2022","journal-title":"ChemistrySelect"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"740","DOI":"10.1016\/0032-3861(81)90007-0","article-title":"Use of NMR data to calculate copolymer reactivity ratios","volume":"22","author":"Rudin","year":"1981","journal-title":"Polymer"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"116743","DOI":"10.1016\/j.bios.2024.116743","article-title":"Recent advances of electrochemical and optical point-of-care biosensors for detecting neurotransmitter serotonin biomarkers","volume":"267","author":"Chavan","year":"2025","journal-title":"Biosens. Bioelectron."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1016\/j.cell.2017.03.023","article-title":"Physiologic medium rewires cellular metabolism and reveals uric acid as an endogenous inhibitor of UMP synthase","volume":"169","author":"Cantor","year":"2017","journal-title":"Cell"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"8953","DOI":"10.1021\/ma301712k","article-title":"Thermal behavior, stability, and decomposition mechanism of poly(N-vinylimidazole)","volume":"45","author":"Fodor","year":"2012","journal-title":"Macromolecules"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1016\/S0141-3910(00)00204-4","article-title":"A detailed study of thermal degradation of poly(2-hydroxyethyl methacrylate)","volume":"72","author":"Demirelli","year":"2001","journal-title":"Polym. Degrad. Stab."}],"container-title":["Biosensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-6374\/16\/8\/430\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,8,9]],"date-time":"2026-08-09T04:25:10Z","timestamp":1786249510000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-6374\/16\/8\/430"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,7]]},"references-count":47,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2026,8]]}},"alternative-id":["bios16080430"],"URL":"https:\/\/doi.org\/10.3390\/bios16080430","relation":{},"ISSN":["2079-6374"],"issn-type":[{"value":"2079-6374","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,7]]}}}