A multifunctional microfluidic platform was demonstrated to monitor the interaction between tumor cells and endothelial cells by integrating a three-dimensional (3D) cell culture unit with a protein detection unit. In such a chip, breast cancer cells MCF7 were seeded into the collagen to form a 3D tumor environment while human umbilical vein endothelial cells (HUVECs) are seeded in the channel next to the collagen matrix. Thus, an in situ growth of angiogenic sprouting can be visualized through fluorescence in the 3D collagen matrix after a coculture of MCF7 and HUVEC after 4 days, which cannot be observed in the 2D culture environment. On the other hand, gold@silver core-shell nanorods were used as surface-enhanced Raman scattering (SERS) immunoprobes for the detection of the secretion of cytokine (vascular endothelial growth factor, VEGF). The limit of detection of the VEGF is 100 pg/mL. Further, as LiCl and bevacizumab can act as a promoter and an inhibitor of VEGF, the dynamic change of the concentration of VEGF under the stimulation of them was monitored by SERS signals. Thus, this integrated SERS microfluidic platform creates opportunity for the fundamental research of interaction between tumors and endothelial cells.

中文翻译：

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使用3D微流体网络对肿瘤与内皮细胞之间的相互作用进行原位可视化和SERS监测。

通过将三维（3D）细胞培养单元与蛋白质检测单元整合在一起，证明了多功能微流控平台可监测肿瘤细胞与内皮细胞之间的相互作用。在这种芯片中，乳腺癌细胞MCF7被植入胶原蛋白中以形成3D肿瘤环境，而人类脐静脉内皮细胞（HUVEC）则被植入胶原蛋白基质附近的通道中。因此，在MCF7和HUVEC共培养4天后，通过3D胶原蛋白基质中的荧光可以观察到血管新生芽的原位生长，这在2D培养环境中无法观察到。另一方面，金@银核-壳纳米棒被用作表面增强拉曼散射（SERS）免疫探针，用于检测细胞因子（血管内皮生长因子，VEGF）的分泌。VEGF的检出限为100pg / mL。此外，由于LiCl和贝伐单抗可以充当VEGF的启动子和抑制剂，因此通过SERS信号监测在它们的刺激下VEGF浓度的动态变化。因此，这种集成的SERS微流体平台为肿瘤与内皮细胞之间相互作用的基础研究创造了机会。