College of Chemistry, Jilin Province Research Center for Engineering and Technology of Spectral Analytical Instruments, Jilin University, Qianjin Street 2699, Changchun, 130012, China.
Nanomedicine Translational Research Center, China-Japan Union Hospital of Jilin University, Sendai Street 126, Changchun, 130033, China.
Biosens Bioelectron. 2022 Sep 15;212:114389. doi: 10.1016/j.bios.2022.114389. Epub 2022 May 20.
Matrix metalloproteinase 2 (MMP-2) is a crucial biomarker of tumor growth, invasion and metastasis. In the present study, a core-satellite magnetic-fluorescent-plasmonic nanosensor (FMNS@Au) was constructed through biological self-assembly to generate localized SERS "hot spots" and an efficient FRET system for the sensitive determination of MMP-2 activity in a SERS-fluorescence dual-mode assay. In this hybrid nanosensor, a biotin-labeled peptide containing a specific MMP-2 substrate (PLGVR) was employed as a bridge for the assembly of gold nanoparticles (AuNPs) and avidin functionalized fluorescent-magnetic nanospheres (FMNS). The modified RB on FMNS served as a Raman reporter and a donor of FRET, while the AuNPs assembled on FMNS acted as SERS substrates and acceptors of FRET. In the presence of MMP-2, the SERS "hot spot" effect was weakened and the FRET system was disrupted through enzymatic cleavage of PLGVR, resulting in a reduction of SERS signal and the recovery of fluorescence emission. Importantly, this combination of SERS and fluorescence assay methods in the dual-mode nanosensor broadened the detection range for MMP-2 to 1-200 ng mL, with a limit of detection of 0.35 ng mL and a limit of quantitation of 1.17 ng mL. In addition, our novel nanosensor affords semi-quantitative sensing of MMP-2 by naked-eye observation and accurate detection of MMP-2 through dual-mode analysis. The practicality of FMNS@Au was validated by determination of MMP-2 activity in cell secretions and human serum samples. The designed FMNS@Au nanosensor holds great potential for clinical diagnosis of protease-related diseases.
基质金属蛋白酶 2（MMP-2）是肿瘤生长、侵袭和转移的关键生物标志物。本研究通过生物自组装构建了一种核-壳型磁性荧光等离子体纳米传感器（FMNS@Au），以产生局域表面等离激元增强拉曼散射（SERS）“热点”和高效的荧光共振能量转移（FRET）体系，用于 MMP-2 活性的灵敏测定，实现 SERS-荧光双模检测。在该混合纳米传感器中，使用含有特定 MMP-2 底物（PLGVR）的生物素化肽作为金纳米粒子（AuNPs）和亲和素功能化荧光磁性纳米球（FMNS）组装的桥梁。FMNS 上修饰的 RB 既作为 SERS 报告基团，又作为 FRET 的供体，而组装在 FMNS 上的 AuNPs 则作为 SERS 底物和 FRET 的受体。在 MMP-2 存在的情况下，通过 PLGVR 的酶切，SERS“热点”效应减弱，FRET 体系被破坏，导致 SERS 信号减弱和荧光发射恢复。重要的是，这种双模纳米传感器中 SERS 和荧光检测方法的结合拓宽了 MMP-2 的检测范围至 1-200ng/mL，检测限为 0.35ng/mL，定量限为 1.17ng/mL。此外，我们的新型纳米传感器通过肉眼观察可实现对 MMP-2 的半定量传感，并通过双模分析可实现对 MMP-2 的准确检测。通过对细胞分泌物和人血清样本中 MMP-2 活性的测定，验证了 FMNS@Au 的实用性。设计的 FMNS@Au 纳米传感器在蛋白酶相关疾病的临床诊断中具有很大的应用潜力。
