Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
Lab Chip. 2017 Jun 27;17(13):2208-2217. doi: 10.1039/c7lc00277g.
Cell secretion dynamics plays a central role in physiological and disease processes. Due to its various temporal profiles, it is essential to implement a precise detection scheme for continuous monitoring of secretion in real time. The current fluorescent and colorimetric approaches hinder such applications due to their multiple time-consuming steps, molecular labeling, and especially the 'snapshot' endpoint readouts. Here, we develop a nanoplasmonic biosensor for real-time monitoring of live cell cytokine secretion in a label-free configuration. Our nanoplasmonic biosensor is composed of gold nanohole arrays supporting extraordinary optical transmission (EOT), which enables sensitive and high-throughput analysis of biomolecules. The nanobiosensor is integrated with an adjustable microfluidic cell module for the analysis of live cells under well-controlled culture conditions. We achieved an outstanding sensitivity for the detection of vascular endothelial growth factor (VEGF) directly in complex cell media. Significantly, the secretion dynamics from live cancer cells were monitored and quantified for 10 hours while preserving good cell viability. This novel approach of probing cytokine secretion activity is compatible with conventional inverted microscopes found in a common biology laboratory. With its simple optical set-up and label-free detection configuration, we anticipate our nanoplasmonic biosensor to be a powerful tool as a lab-on-chip device to analyze cellular activities for fundamental cell research and biotechnologies.
细胞分泌动力学在生理和疾病过程中起着核心作用。由于其具有各种时间分布特征，因此必须采用精确的检测方案，以便实时连续监测分泌情况。目前的荧光和比色法由于需要多个耗时的步骤、分子标记，特别是需要采用“快照”终点读取方式，因此阻碍了这些应用。在这里，我们开发了一种纳米等离子体生物传感器，用于实时无标记监测活细胞细胞因子的分泌情况。我们的纳米等离子体生物传感器由支持超常光传输（EOT）的金纳米孔阵列组成，能够对生物分子进行敏感和高通量分析。该纳米生物传感器与可调节的微流控细胞模块集成在一起，可在良好控制的培养条件下分析活细胞。我们实现了对复杂细胞培养基中血管内皮生长因子（VEGF）的出色检测灵敏度。重要的是，在保持良好细胞活力的情况下，对活癌细胞的分泌动力学进行了 10 小时的监测和定量。这种探测细胞因子分泌活性的新方法与普通生物学实验室中常见的倒置显微镜兼容。由于其具有简单的光学设置和无标记检测配置，我们预计我们的纳米等离子体生物传感器将成为一种强大的工具，作为一种芯片实验室设备，用于分析细胞活性，从而用于基础细胞研究和生物技术。
