Dongkyu Kang, Suyeon Kim, Yeongchang Goh, Minseo Kim, Sun-Hak Lee, Jung-Hoon Kwon, Sang Hwan Nam, Joonseok Lee
{"title":"Water-insensitive NIR-I-to-NIR-I down-shifting nanoparticles enable stable biomarker detection at low power thresholds in opaque aqueous environments","authors":"Dongkyu Kang, Suyeon Kim, Yeongchang Goh, Minseo Kim, Sun-Hak Lee, Jung-Hoon Kwon, Sang Hwan Nam, Joonseok Lee","doi":"10.1038/s41377-025-01882-2","DOIUrl":null,"url":null,"abstract":"<p>Luminescence quenching in aqueous environments poses a challenge for practical applications. Lanthanide-doped up-conversion nanoparticles (UCNPs), representative of near-infrared (NIR)-emitting phosphors, typically utilize Yb<sup>3+</sup> ions as sensitizers, requiring 980 nm light. This wavelength coincides with the transitions of water molecules, interfering with population dynamics, and continuous irradiation causes unintended heating. Although Nd<sup>3+</sup> ions, which absorb at 800 nm, serve as alternative sensitizers, their practical use is limited by low quantum yield (Q.Y.). In this study, we developed water-insensitive down-shifting nanoparticles (WINPs) functioning within the NIR-I range (700–900 nm) to avoid water interference. Characterization through single-particle-level spectroscopy demonstrated water-insensitive properties, with identical powers density and lifetime profiles under both dry and water conditions. The WINPs achieved a high Q.Y. of 22.1 ± 0.9%, allowing operation at a detection limit power 15-fold lower than UCNPs, effectively eliminating background noise and enhancing overall performance. To assess diagnostic potential, we validated WINP-based lateral flow immunoassay (LFA) for detecting avian influenza viruses (AIVs) in 65 opaque clinical samples, achieving 100% sensitivity and an area under the curve (AUC) of 1.000 at only 100 mW cm<sup>−2</sup>. These findings highlight the potential of WINPs as water-insensitive NIR phosphors that can operate at low power, even in water-rich environments.</p>","PeriodicalId":18069,"journal":{"name":"Light-Science & Applications","volume":"71 1","pages":""},"PeriodicalIF":20.6000,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Light-Science & Applications","FirstCategoryId":"1089","ListUrlMain":"https://doi.org/10.1038/s41377-025-01882-2","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"OPTICS","Score":null,"Total":0}
引用次数: 0
Abstract
Luminescence quenching in aqueous environments poses a challenge for practical applications. Lanthanide-doped up-conversion nanoparticles (UCNPs), representative of near-infrared (NIR)-emitting phosphors, typically utilize Yb3+ ions as sensitizers, requiring 980 nm light. This wavelength coincides with the transitions of water molecules, interfering with population dynamics, and continuous irradiation causes unintended heating. Although Nd3+ ions, which absorb at 800 nm, serve as alternative sensitizers, their practical use is limited by low quantum yield (Q.Y.). In this study, we developed water-insensitive down-shifting nanoparticles (WINPs) functioning within the NIR-I range (700–900 nm) to avoid water interference. Characterization through single-particle-level spectroscopy demonstrated water-insensitive properties, with identical powers density and lifetime profiles under both dry and water conditions. The WINPs achieved a high Q.Y. of 22.1 ± 0.9%, allowing operation at a detection limit power 15-fold lower than UCNPs, effectively eliminating background noise and enhancing overall performance. To assess diagnostic potential, we validated WINP-based lateral flow immunoassay (LFA) for detecting avian influenza viruses (AIVs) in 65 opaque clinical samples, achieving 100% sensitivity and an area under the curve (AUC) of 1.000 at only 100 mW cm−2. These findings highlight the potential of WINPs as water-insensitive NIR phosphors that can operate at low power, even in water-rich environments.