Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya Suruga-Ku, Shizuoka, 422-8529, Japan.
Graduate School of Integrated Science and Technology, Shizuoka University, 836 Ohya Suruga-Ku, Shizuoka, 422-8529, Japan.
Mikrochim Acta. 2024 Aug 24;191(9):560. doi: 10.1007/s00604-024-06600-0.
The development of an innovative approach is explored to amplify the signal of a surface-enhanced Raman scattering (SERS)-based detection system using a novel nanotag: Au@Ag NPs covered by satellite AuNPs and conjugated by 4-mercaptbenzoic acid (4-MBA) as a Raman tag (Au@Ag-MBA-AuNPs). The Au@Ag-MBA-AuNPs nanotags showed strong SERS activities with an enhancement factor in the 10 order of magnitude. This indicates the formation of many hot spots due to the combination of core-shell nanoparticles and satellite AuNPs on the surface of Au@Ag-MBA NPs. The newly fabricated nanotags were employed in a small-sized Palmtop Raman spectrometer. A concentration-dependent increase in SERS intensity was observed in the norovirus-like particle (NoV-LP) concentration range 10 fg/mL to 100 pg/mL with a detection limit of 0.76 fg/mL. Even in the severe interfering matrices, this detection method's coefficient of variation was less than 10%. This detection system was approximately 10 times more sensitive than commercially available ELISA kits. Norovirus in clinical samples was detected over a wide concentration range of 1.0 × 10 - 1.0 × 10 RNA copy number/mL with a detection limit of 7.8 RNA copy number/mL, indicating sensitivity comparable to real-time PCR. These results suggest that this detection system is stable in a complex matrix and has the potential for detecting norovirus in clinical samples with a small Palmtop Raman spectrometer.
探索了一种创新方法，使用新型纳米标签：Au@Ag NPs 覆盖卫星 AuNPs 并用 4-巯基苯甲酸（4-MBA）作为拉曼标记（Au@Ag-MBA-AuNPs）来放大基于表面增强 Raman 散射（SERS）的检测系统的信号。Au@Ag-MBA-AuNPs 纳米标签表现出很强的 SERS 活性，增强因子达到 10 数量级。这表明由于核壳纳米粒子和卫星 AuNPs 在 Au@Ag-MBA NPs 表面的结合形成了许多热点。新制备的纳米标签被用于小型掌上 Raman 光谱仪。在诺如病毒样颗粒（NoV-LP）浓度范围为 10 fg/mL 至 100 pg/mL 时，观察到 SERS 强度与浓度呈依赖性增加，检测限为 0.76 fg/mL。即使在严重干扰的基质中，这种检测方法的变异系数也小于 10%。与市售 ELISA 试剂盒相比，该检测系统的灵敏度约提高了 10 倍。在临床样本中，检测到诺如病毒的浓度范围为 1.0×10 - 1.0×10 RNA 拷贝数/mL，检测限为 7.8 RNA 拷贝数/mL，表明与实时 PCR 相当的灵敏度。这些结果表明，该检测系统在复杂基质中稳定，具有使用小型掌上 Raman 光谱仪检测临床样本中诺如病毒的潜力。
