Kartashova Anna D, Gonchar Kirill A, Chermoshentsev Dmitry A, Alekseeva Ekaterina A, Gongalsky Maxim B, Bozhev Ivan V, Eliseev Andrei A, Dyakov Sergey A, Samsonova Jeanne V, Osminkina Liubov A
Lomonosov Moscow State University, Faculty of Physics, Leninskie Gory 1, 119991 Moscow, Russia.
Skolkovo Institute of Science and Technology, Center for Photonics and Quantum Materials, Bolshoy Boulevard 30, bld. 1, 143025 Moscow, Russia.
ACS Biomater Sci Eng. 2022 Oct 10;8(10):4175-4184. doi: 10.1021/acsbiomaterials.1c00728. Epub 2021 Nov 14.
Bilirubin (BR) is a product of hemoglobin breakdown, and its increasing levels in the blood may indicate liver disorders and lead to jaundice. Kernicterus is most dangerous in newborns when the unconjugated BR concentration can quickly rise to toxic levels, causing neurological damage and even death. The development of an accurate, fast, and sensitive sensor for BR detection will help reduce diagnostic time and ensure successful treatment. In this study, we propose a new method for creating a surface-enhanced Raman scattering (SERS)-active substrate based on gold-decorated silicon nanowires (Au@SiNWs) for sensitive label-free BR detection. Gold-assisted chemical etching of crystalline silicon wafers was used to synthesize SiNWs, the tops of which were then additionally decorated with gold nanoparticles. The low detection limit of model analyte 4-mercaptopyridine down to the concentration of 10 M demonstrated the excellent sensitivity of the obtained substrates for SERS application. The theoretical full-wave electromagnetic simulations of Raman scattering in the Au@SiNW substrates showed that the major contribution to the total SERS signal comes from the analyte molecules located on the SiNW surface near the gold nanoparticles. Therefore, for efficient BR adsorption and SERS detection, the surface of the SiNWs was modified with amino groups. Label-free detection of BR using amino modified Au@SiNWs with high point-to-point, scan-to-scan, and batch-to-batch reproducibility with a detection limit of 10 M has been demonstrated. Artificial urine, mimicking human urine samples, was used as the matrix to get insights into the influence of different parameters such as matrix complexity on the overall BR SERS signal. The signal stability was demonstrated for 7 days after adsorption of BR with a concentration of 5 × 10 M, which is the required sensitivity for clinical applications.
胆红素（BR）是血红蛋白分解的产物，血液中其水平升高可能表明肝脏疾病并导致黄疸。当未结合的BR浓度迅速升至有毒水平时，核黄疸对新生儿最为危险，会导致神经损伤甚至死亡。开发一种准确、快速且灵敏的BR检测传感器将有助于缩短诊断时间并确保治疗成功。在本研究中，我们提出了一种基于金修饰硅纳米线（Au@SiNWs）创建表面增强拉曼散射（SERS）活性基底的新方法，用于灵敏的无标记BR检测。采用金辅助化学蚀刻晶体硅片来合成SiNWs，然后在其顶部额外装饰金纳米颗粒。模型分析物4-巯基吡啶的低检测限低至10⁻⁹ M，证明了所制备基底在SERS应用方面具有出色的灵敏度。对Au@SiNW基底中拉曼散射的理论全波电磁模拟表明，总SERS信号的主要贡献来自位于金纳米颗粒附近SiNW表面的分析物分子。因此，为了实现BR的有效吸附和SERS检测，对SiNWs表面进行了氨基修饰。已证明使用氨基修饰的Au@SiNWs对BR进行无标记检测具有高的点对点、扫描间和批次间重现性，检测限为10⁻⁹ M。使用模拟人类尿液样本的人工尿液作为基质，以深入了解不同参数（如基质复杂性）对整体BR SERS信号的影响。在吸附浓度为5×10⁻⁸ M的BR后，信号稳定性在7天内得到了证明，这是临床应用所需的灵敏度。
