School of Materials and Chemistry, University of Shanghai for Science & Technology, Shanghai, 200093, China.
Department of Critical Care Medicine, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai 200030, China.
Nanoscale. 2022 Apr 21;14(16):6212-6219. doi: 10.1039/d2nr00091a.
Rapid and accurate detection of myocardial infarction (MI) can boost the patient's chance of survival. Surface enhanced Raman scattering (SERS) is an outstanding diagnostic technique because of its strong light stability, high resolution, and qualitative and quantitative analysis based on the characteristic fingerprint. However, its reliability, stability and specificity remain to be improved, especially in the quantitative analysis of serum samples. In this study, we developed silver nanoparticles (Ag NPs) on the surface of polydopamine (PDA) as a SERS substrate and found that PDA could act as a reducing agent to support the nucleation and growth of Ag NPs and control the distance and aggregation of Ag NPs to stabilize the Raman signal. In a standard phosphate buffered saline (PBS) environment, PDA@Ag could reach a low detection limit of 0.01 ng mL cardiac troponin I (cTn I) with a good linear relationship. At the same time, the PDA@Ag substrate also possessed excellent stability, specificity and biocompatibility for cTn I detection. In addition, we verified the application potentiality of PDA@Ag in real serum samples and found that the performance of SERS was almost the same as that in PBS. This excellent detection performance of PDA@Ag could be attributed to both the enhanced electromagnetic field and the increased Raman cross-section, dominated by the gap distance between Ag NPs, reaction force between the antigen and the antibody and excellent biocompatibility and reducibility of PDA. In conclusion, this work may provide a new perspective for the synthesis and growth of a uniform SERS substrate on the carrier to achieve the stability and specificity of SERS-based biological detection of MI.
快速准确地检测心肌梗死（MI）可以提高患者的生存机会。表面增强拉曼散射（SERS）是一种出色的诊断技术，因为它具有很强的光稳定性、高分辨率以及基于特征指纹的定性和定量分析。然而，其可靠性、稳定性和特异性仍有待提高，尤其是在血清样本的定量分析方面。在这项研究中，我们在聚多巴胺（PDA）表面上开发了银纳米粒子（Ag NPs）作为 SERS 基底，并发现 PDA 可以作为还原剂来支持 Ag NPs 的成核和生长，并控制 Ag NPs 的距离和聚集以稳定拉曼信号。在标准磷酸盐缓冲盐水（PBS）环境中，PDA@Ag 可以达到 0.01ng mL 心脏肌钙蛋白 I（cTn I）的低检测限，具有良好的线性关系。同时，PDA@Ag 基底还具有出色的稳定性、特异性和生物相容性，可用于 cTn I 检测。此外，我们验证了 PDA@Ag 在实际血清样本中的应用潜力，发现 SERS 的性能与 PBS 中的性能几乎相同。PDA@Ag 的这种出色检测性能可归因于增强的电磁场和增加的拉曼截面，这主要由 Ag NPs 之间的间隙距离、抗原和抗体之间的反作用力以及 PDA 的出色生物相容性和还原性决定。总之，这项工作可能为在载体上合成和生长均匀的 SERS 基底以实现基于 SERS 的 MI 生物检测的稳定性和特异性提供新的视角。
