Academic Journal
Nucleic-Acid-Amplification-Free and Fluorescent-Label-Free RNA Detection with a Dual-Scale Gold Nanoparticle-Enhanced Fiber-Optic SPR Biosensor.
| Τίτλος: | Nucleic-Acid-Amplification-Free and Fluorescent-Label-Free RNA Detection with a Dual-Scale Gold Nanoparticle-Enhanced Fiber-Optic SPR Biosensor. |
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| Συγγραφείς: | Li X; State Key Laboratory of Synthetical Automation for Process Industries, College of Information Science and Engineering, Northeastern University, Shenyang, Liaoning110819, China.; Leibniz Institute of Photonic Technology (IPHT), Jena07745, Germany., Zhao X; State Key Laboratory of Synthetical Automation for Process Industries, College of Information Science and Engineering, Northeastern University, Shenyang, Liaoning110819, China., Zhang J; State Key Laboratory of Synthetical Automation for Process Industries, College of Information Science and Engineering, Northeastern University, Shenyang, Liaoning110819, China., Zhou X; State Key Laboratory of Synthetical Automation for Process Industries, College of Information Science and Engineering, Northeastern University, Shenyang, Liaoning110819, China., Zhang Y; State Key Laboratory of Synthetical Automation for Process Industries, College of Information Science and Engineering, Northeastern University, Shenyang, Liaoning110819, China., Zhao Y; State Key Laboratory of Synthetical Automation for Process Industries, College of Information Science and Engineering, Northeastern University, Shenyang, Liaoning110819, China., Warren-Smith SC; Future Industries Institute, Adelaide University, Mawson Lakes, Adelaide, South Australia5095, Australia.; Institute for Photonics and Advanced Sensing (IPAS) and School of Physical Sciences, Adelaide University, Adelaide, South Australia5005, Australia., Nguyen LV; Future Industries Institute, Adelaide University, Mawson Lakes, Adelaide, South Australia5095, Australia.; Institute for Photonics and Advanced Sensing (IPAS) and School of Physical Sciences, Adelaide University, Adelaide, South Australia5005, Australia. |
| Πηγή: | Analytical chemistry [Anal Chem] 2026 Aug 25; Vol. 98 (33), pp. 24489-24497. |
| Τύπος έκδοσης: | Journal Article; Research Support, Non-U.S. Gov't |
| Γλώσσα: | English |
| Στοιχεία περιοδικού: | Publisher: American Chemical Society Country of Publication: United States NLM ID: 0370536 Publication Model: Print Cited Medium: Internet ISSN: 1520-6882 (Electronic) Linking ISSN: 00032700 NLM ISO Abbreviation: Anal Chem Subsets: MEDLINE |
| Imprint Name(s): | Original Publication: Washington, American Chemical Society. |
| Ιατρικοί όροι (MeSH): | Gold*/chemistry , Surface Plasmon Resonance*/methods , Surface Plasmon Resonance*/instrumentation , Metal Nanoparticles*/chemistry , RNA*/analysis , Biosensing Techniques* , Fiber Optic Technology*, Optical Fibers |
| Περίληψη: | Highly sensitive RNA detection at ultralow concentrations remains challenging for conventional surface plasmon resonance (SPR) biosensors because low-molecularI biomolecules induce only weak effective refractive-index perturbations within the limited evanescent-field penetration depth. Here, we report a dual-scale gold nanoparticle (AuNP)-enhanced fiber-optic SPR biosensor that overcomes this intrinsic limitation through a mechanism-guided sandwich-type architecture. The sensor employs a multimode fiber-single-mode fiber-multimode fiber (MMF-SMF-MMF) configuration to enhance evanescent-field excitation at the metal-dielectric interface. Plasmonic amplification is achieved by decoupling probe immobilization and signal enhancement into two AuNP populations with distinct roles: large AuNPs functionalized with probe DNA form a stable, high-density recognition layer on the gold-coated fiber surface, while small AuNPs conjugated with target RNA act as mobile amplification units. Upon specific DNA-RNA hybridization, a hierarchical plasmonic sandwich structure is formed within the effective sensing volume, enabling synergistic enhancement through near-field electromagnetic coupling and mass-loading effects. Finite-element simulations and experiments consistently demonstrate substantially stronger localized electromagnetic fields and higher refractive-index sensitivity compared with bare gold films and monolayer AuNP-modified SPR sensors. Importantly, the assay does not rely on nucleic-acid amplification reactions or fluorescent labeling. The sensor exhibits a linear response to RNA concentrations from 0 to 700 fM, achieving a sensitivity of 6.5 pm/fM and a detection limit of 97 fM, corresponding to a 7.5-fold signal enhancement over conventional single-layer AuNP-based SPR sensors. This work demonstrates that a dual-scale AuNP-assisted sandwich architecture can effectively amplify weak SPR responses from thiol-modified model RNA targets without requiring nucleic-acid amplification reactions. Further optimization toward direct detection of unmodified RNA in real biological samples will be pursued in future work. (© 2026 American Chemical Society.) |
| Grant Information: | 62373088 National Natural Science Foundation of China; 62522310 National Natural Science Foundation of China; N2404022 Fundamental Research Funds for the Central Universities; N2424017 Fundamental Research Funds for the Central Universities; 2022QNRC001 Young Elite Scientists Sponsorship Program by CAST; 2024JH3/10200009 National Natural Science Foundation of Liaoning Province; FT200100154 Australian Research Council (ARC) Future Fellowship; NA Alexander von Humboldt Foundation |
| Substance Nomenclature: | 7440-57-5 (Gold) 63231-63-0 (RNA) |
| Entry Date(s): | Date Created: 20260831 Date Completed: 20260831 Latest Revision: 20260911 |
| Update Code: | 20260911 |
| DOI: | 10.1021/acs.analchem.6c03968 |
| PMID: | 42674042 |
| Βάση Δεδομένων: | MEDLINE |
| ISSN: | 1520-6882 |
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| DOI: | 10.1021/acs.analchem.6c03968 |