Multiplex surface-enhanced Raman scattering (SERS) detection of markers without background in tumor biosystems has its superiority over other optical methods. Herein, we reported a strategy of quantitative discrimination of two breast cancer cell subtypes. Based on our previous studies, two kinds of Prussian blue analogue coated gold nanoparticles (Au@PBA NPs) were designed and synthesized by the replacement of Fe²⁺ with Pb²⁺ or Cu²⁺. Therefore, two distinct SERS emissions of C≡N bonds at 2122 cm^-1 and 2176 cm^-1 have been acquired. When modified with aptamers of epithelial cell adhesion molecule (EpCAM) and epidermal growth factor receptor (EGFR), which are both expressed in MCF-7 and MDA-MB-231 cell lines but in different levels, the SERS nanoprobes simultaneously identified the relative expression of these biomarkers on the cell surface, providing a good example for ratiometric detection in biosystems without any interference. Each surface marker of tumor cells corresponds to a single SERS emission. Thus, each subtype could be described in a molecular profiling way through duplex C≡N bonds-based SERS emission, which is more advanced than traditional flow cytometry method.

肿瘤生物系统中无背景标记的多重表面增强拉曼散射（SERS）检测具有优于其他光学方法的优势。在这里，我们报道了两种乳腺癌细胞亚型的定量区分策略。根据我们以前的研究，二种普鲁士蓝涂覆类似物金纳米颗粒（金@ PBA NPS），设计并通过取代Fe合成²⁺与铅²⁺或Cu ²⁺。因此，在2122 cm ^-1和2176 cm ^-1处有两个不同的C twoN键SERS发射已被收购。当用均在MCF-7和MDA-MB-231细胞系中表达但水平不同的上皮细胞粘附分子（EpCAM）和表皮生长因子受体（EGFR）的适体修饰时，SERS纳米探针同时鉴定出相对表达这些生物标志物在细胞表面的表达，为在生物系统中进行比率检测而没有任何干扰提供了一个很好的例子。肿瘤细胞的每个表面标记对应一个SERS发射。因此，每个亚型都可以通过基于双链C≡N键的SERS发射以分子谱描述，这比传统的流式细胞仪方法更先进。