文献类型：期刊文献

英文题名：Air-coupled micro-disk resonator for robust reproducible sensing of trace phosphate ions in the tap water and biological samples

作者：Li, Houchang[1,2]; Liu, Bin[3]; Liu, Juan[3]; Li, Zefeng[2]; Gao, Yuze[4]; Ma, Haili[5]; Pu, Shengli[6]; Rao, Lan[2]; Zhou, Xian[1]; Yuan, Jinhui[1,2]; Farrell, Gerald[7]; Wu, Qiang[5]

第一作者：Li, Houchang

机构：[1] School of Computer and Communication Engineering, University of Science & Technology Beijing, Beijing, 100083, China; [2] State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing, 100876, China; [3] Key Laboratory of Optoelectronic Information Science and Technology of Jiangxi Province, Nanchang Hangkong University, Nanchang, 330063, China; [4] School of Tourism, Beijing Union University, Beijing, 100101, China; [5] Faculty of Science and Environment, Northumbria University, Newcastle upon Tyne, NE18ST, United Kingdom; [6] College of Science and Shanghai Key Laboratory of Modern Optical System, University of Shanghai for Science and Technology, Shanghai, 200093, China; [7] Photonics Research Centre, School of Electrical and Electronic Engineering, City Campus, Technological University Dublin, Dublin 7, Ireland

第一机构：School of Computer and Communication Engineering, University of Science & Technology Beijing, Beijing, 100083, China

年份：2026

卷号：463

外文期刊名：Sensors and Actuators B: Chemical

收录：EI(收录号：20261920659984)

语种：英文

外文关键词：Crystal resonators - Deposition - Fluorine compounds - Ions - Magnesium compounds - Microresonators - Optical resonators - Precision engineering - Trace analysis - Whispering gallery modes

摘要：A micro-disk resonator (MDR) sensor was developed and rigorously characterized for the rapid and robust detection of ultra-trace phosphate ions (PO?3?) in both tap water and complex biological matrices. Operating in the whispering gallery mode (WGM), the MDR is precision-engineered from a high-purity magnesium fluoride (MgF?) crystal by ultra-precision machining to achieve nanometre-scale surface smoothness. Notably, the device has its coupling region in air and its sensing region immersed in liquid, resulting in high-quality factor performance and enhanced system stability, which is a significant improvement over conventional resonator architectures in which both the coupling and sensing regions are immersed in liquid. The surface of the MDR was functionalized with ferritin immobilized via reduced graphene oxide (rGO) nanoparticles, enabling high selectivity for PO?3 ?. The sensor exhibited a wide linear detection range from 5 × 10?6 to 1 × 10?2 mg/L, with a limit of detection (LoD) as low as 4.30 × 10?? mg/L, demonstrating competitive sensitivity and offering a distinct air-coupled WGM sensing architecture. The assay could be completed within 10 min and exhibited high selectivity in the presence of competing anions. The sensor was applied to real samples, including tap water and biological fluids, with spiked recovery rates ranging from 96% to 104%, demonstrating its practicality. Copyright ? 2026. Published by Elsevier B.V.