Institute of Materials Science and Engineering, National Central University, Taoyuan City 32001, Taiwan; Department of Materials Science and Engineering, University of California, Irvine, Orange, CA 92697, USA.
Institute of Materials Science and Engineering, National Central University, Taoyuan City 32001, Taiwan.
Biosens Bioelectron. 2019 Oct 1;142:111509. doi: 10.1016/j.bios.2019.111509. Epub 2019 Jul 18.
Circulating tumor cells (CTCs) and plasma levels of Epstein-Barr virus (EBV) DNA are sensitive prognostic tools for monitoring disease status in nasopharyngeal carcinoma (NPC) patients. Herein, we introduce a novel and low-cost platform for capturing CTCs, the Si nanowires/microscale pyramids (NWs/MPs) hierarchical substrate, which could capture NPC cells in vitro and also detect EBV DNA at very low concentrations. In this study, Si NWs/MPs hierarchical substrates with varying wire length were fabricated using a metal-assisted chemical etching method. Anti-EpCAM antibodies were further conjugated on the substrate for capturing NPC CTCs in vitro. Capture efficiency was evaluated using immunofluorescence and scanning electronic microscopy (SEM) was utilized to understand cell morphology. The Si NWs/MPs substrate was also transformed into a Surface enhanced Raman scattering (SERS) substrate by coating with Ag nanoparticles (AgNPs) for detection of EBV DNA by Raman spectroscopy. The results demonstrated that Si NWs/MPs with 20 min of etch time had the best capturing performance. Additionally, SEM observations revealed good contact of CTCs with Si NWs/MPs substrates. Moreover, the AgNPs-coated NWs/MPs substrate was shown to be a sensitive EBV DNA detector, by which the DNA detection limit can reach up to 10M. In conclusion, the Si NWs/MPs platform not only exhibits superior cell capturing ability, but also can sensitively detect EBV DNA at very low concentrations. This platform has great potential to become a promising diagnostic tool for monitoring disease status and prognostication of NPC patients.
循环肿瘤细胞 (CTCs) 和血浆中 EBV 病毒 (EBV) DNA 水平是监测鼻咽癌 (NPC) 患者疾病状态的敏感预后工具。在此，我们引入了一种新型的、低成本的 CTCs 捕获平台，即硅纳米线/微尺度金字塔 (NWs/MPs) 分级基底，它可以体外捕获 NPC 细胞，并且还可以检测到极低浓度的 EBV DNA。在这项研究中，使用金属辅助化学蚀刻法制备了具有不同线长的 Si NWs/MPs 分级基底。进一步将抗 EpCAM 抗体共轭到基底上，用于体外捕获 NPC CTCs。通过免疫荧光法评估捕获效率，并利用扫描电子显微镜 (SEM) 来了解细胞形态。Si NWs/MPs 基底还通过涂覆 Ag 纳米粒子 (AgNPs) 转化为表面增强拉曼散射 (SERS) 基底，通过拉曼光谱检测 EBV DNA。结果表明，蚀刻时间为 20 分钟的 Si NWs/MPs 具有最佳的捕获性能。此外，SEM 观察显示 CTCs 与 Si NWs/MPs 基底有良好的接触。此外，AgNPs 涂覆的 NWs/MPs 基底被证明是一种灵敏的 EBV DNA 检测器，其 DNA 检测限可低至 10M。总之，Si NWs/MPs 平台不仅表现出优异的细胞捕获能力，而且还可以灵敏地检测极低浓度的 EBV DNA。该平台有望成为监测 NPC 患者疾病状态和预后的有前途的诊断工具。
