College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
College of Chemistry and Chemical Engineering, Institute for Conservation and Utilization of Agro-bioresources in Dabie Mountains, Xinyang Normal University, Xinyang 464000, China.
Anal Chem. 2021 Jun 8;93(22):7917-7924. doi: 10.1021/acs.analchem.1c00621. Epub 2021 May 21.
Three-dimensional (3D) cell culture can better reproduce the cell environment and has been extensively used in fields such as tissue engineering, drug screening, and pathological research. Despite the tremendous advancement of 3D cultures, an analysis technique that could collect real-time information of the biological processes therein is sorely lacking. Electrochemical sensing with fast response and high sensitivity has played a vital role in real-time monitoring of living cells, but most current sensors are based on planar electrodes and fail to perfectly match the 3D cell culture matrix. Herein, we developed a robust 3D electrochemical sensor based on functionalized graphene foam (GF), which could be integrated with hydrogels for the 3D culture and monitoring of cells for the first time. Specifically, platinum nanoparticles (Pt NPs) electrodeposited on GF (GF/Pt NPs) conferred the prominent electrochemical sensing performance, and the anti-fouling coating of poly(3,4-ethylenedioxythiophene) (PEDOT) endowed the GF/Pt NPs electrode with greatly improved stability. As a proof of concept, collagen hydrogel with microglia seeded in was filled into the interspace of the 3D GF/Pt NPs/PEDOT sensor to establish an integrated platform, which allowed the successful real-time monitoring of reactive oxygen species released from microglia in the collagen matrix. Given the versatility, our proposed biosensor in conjunction with various 3D culture models will serve as an excellent tool to provide biochemical information of cells under their -like microenvironment.
三维（3D）细胞培养可以更好地模拟细胞环境，已广泛应用于组织工程、药物筛选和病理研究等领域。尽管 3D 培养取得了巨大进展，但缺乏一种能够实时收集其中生物过程信息的分析技术。电化学传感具有快速响应和高灵敏度的特点，在实时监测活细胞方面发挥了重要作用，但目前大多数传感器都是基于平面电极，无法与 3D 细胞培养基质完美匹配。在此，我们开发了一种基于功能化石墨烯泡沫（GF）的强大 3D 电化学传感器，它首次可以与水凝胶集成，用于 3D 细胞培养和监测。具体来说，沉积在 GF 上的铂纳米粒子（Pt NPs）（GF/Pt NPs）赋予了突出的电化学传感性能，聚（3,4-亚乙基二氧噻吩）（PEDOT）的防污涂层赋予了 GF/Pt NPs 电极极大的稳定性。作为概念验证，填充有接种小胶质细胞的胶原蛋白水凝胶被填充到 3D GF/Pt NPs/PEDOT 传感器的间隙中，以建立一个集成平台，该平台允许从小胶质细胞在胶原蛋白基质中释放的活性氧进行实时监测。鉴于多功能性，我们提出的生物传感器与各种 3D 培养模型结合使用将成为提供类似微环境下细胞生化信息的优秀工具。
