Martino Sara, Yilmaz Deniz, Tammaro Chiara, Misso Gabriella, Esposito Alessandro, Falco Michela, Cossu Alessia Maria, Lombardi Angela, Amler Evzen, Divin Radek, Giannetti Ambra, Scrima Marianna, Dardano Principia, De Stefano Luca, Rea Ilaria, De Luca Anna Chiara, Caraglia Michele
Department of Precision Medicine, University of Campania "Luigi Vanvitelli", 80138, Naples, Italy; Institute of Applied Sciences and Intelligent Systems "Eduardo Caianiello", Unit of Naples, National Research Council, 80131, Naples, Italy.
Institute for Experimental Endocrinology and Oncology "G. Salvatore"-Second Unit, National Research Council, 80131, Naples, Italy.
Talanta. 2025 Apr 1;285:127293. doi: 10.1016/j.talanta.2024.127293. Epub 2024 Nov 29.
MicroRNAs (miRNAs) are small non-coding RNAs (18-22 nucleotides) that regulate gene expression and are associated with various diseases, including Laryngeal Cancer (LCa), which has a high mortality rate due to late diagnosis. Traditional methods for miRNA detection present several drawbacks (time-consuming steps, high cost and high false positive rate). Early-stage diagnosis and selective detection of miRNAs remain challenging. This study proposes a 3D flexible biosensor that combines nanofibers (NFs), gold nanoparticles (AuNPs), and an inverse molecular sentinel (iMS) for enzyme-free, SERS-based detection of miRNA-223-3p, evaluated as a potential LCa biomarker. The electrospun flexible nanofibers decorated with AuNPs enhance Raman signal. Selective detection of miRNA-223-3p is achieved by immobilizing an iMS-DNA probe labeled with a Raman reporter (Cyanine 3) on the AuNPs. The iMS distinctive stem-and-loop structure undergoes a conformational change upon interaction with the miRNA-223-3p, producing an "on to off" SERS signal. The proposed sensor demonstrated a linear detection range from 10 to 250 fM, with a limit of detection (LOD) of 19.50 ± 0.05 fM. The sensor selectivity was confirmed by analyzing the SERS signal behaviour in the presence of both Non-complementary miRNA and miRNA with three mismatched base pairs. This easily fabricable sensor requires no amplification and offers key advantages, including sensitivity, flexibility, and cost-effectiveness.
微小RNA（miRNA）是一类小的非编码RNA（18 - 22个核苷酸），可调节基因表达，并与多种疾病相关，包括喉癌（LCa），喉癌由于诊断较晚而死亡率很高。传统的miRNA检测方法存在一些缺点（步骤耗时、成本高和假阳性率高）。miRNA的早期诊断和选择性检测仍然具有挑战性。本研究提出了一种三维柔性生物传感器，该传感器结合了纳米纤维（NFs）、金纳米颗粒（AuNPs）和反向分子标记物（iMS），用于基于表面增强拉曼散射（SERS）的无酶检测miRNA - 223 - 3p，miRNA - 223 - 3p被评估为一种潜在的喉癌生物标志物。用AuNPs修饰的电纺柔性纳米纤维可增强拉曼信号。通过将标记有拉曼报告分子（花菁3）的iMS - DNA探针固定在AuNPs上，实现对miRNA - 223 - 3p的选择性检测。iMS独特的茎环结构在与miRNA - 223 - 3p相互作用时会发生构象变化，产生“开 - 关”SERS信号。所提出的传感器的线性检测范围为10至250 fM，检测限（LOD）为19.50±0.05 fM。通过分析在非互补miRNA和具有三个错配碱基对的miRNA存在下的SERS信号行为，证实了传感器的选择性。这种易于制造的传感器无需扩增，具有灵敏度高、柔韧性好和成本效益高等关键优势。
