AbstractThe authors describe a rapid and direct SERS-based immunoassay for the determination of AFP, an important marker for diagnosis of hepatocellular carcinoma. Silver nanoparticles (AgNPs; 36 nm i.d.) serve as a support to immobilize antibody and as a SERS intensifier, and AFP-modified gold nanoparticles are employed as capturing substrate. Direct and quantitative detection of AFP is accomplished with a limit detection as low as 5 ng·mL−1. Compared to assays based on the use of metal nanoparticles, the use of gold-silver nanoparticle heterodimers as an active SERS substrate can save costs because only a single antibody is required. Moreover, the high selectivity and good linear relationship of detecting AFP in fetal bovine serum indicates its potential applicability for the direct analysis of clinical samples. Graphical abstractDirect and quantitative determination of AFP antigen utilizing SERS has been was successfully presented and applied to detect alpha fetoprotein antigen in fetal bovine serum with detection limit of 2 ng•mL−1.

中文翻译：

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通过银纳米颗粒增强的 SERS 和 AFP 修饰的金纳米颗粒作为捕获底物直接测定肿瘤标志物 AFP

摘要作者描述了一种快速、直接的基于 SERS 的免疫测定法，用于测定 AFP，这是诊断肝细胞癌的重要标志物。银纳米粒子 (AgNPs; 36 nm id) 作为固定抗体的载体和 SERS 增强剂，AFP 修饰的金纳米粒子用作捕获基底。AFP 的直接定量检测是通过低至 5 ng·mL-1 的检测限完成的。与基于使用金属纳米粒子的分析相比，使用金银纳米粒子异二聚体作为活性 SERS 底物可以节省成本，因为只需要一种抗体。此外，检测胎牛血清中 AFP 的高选择性和良好的线性关系表明其潜在适用于临床样品的直接分析。