Cell Control via Spatiotemporal Microenvironmental pH Modulation

微环境pH是细胞功能和发病机制中的关键因素。控制功能和行为 通过调节pH来调节细胞微环境是促进细胞生物学和组织发展的关键 在药物输送和再生医学方面的工程和使能应用。然而，基于pH的细胞 控制仍然是一个挑战，因为缺乏手段来实时、空间选择性地调制 微环境pH值。而细胞系统中的pH微环境在时间和时间上具有高度的异质性 已知的pH调节方法是通过CO_2/HCO_3−缓冲和H+扩散，这是缓慢的， 各向同性的，非特定的。因此，迫切需要在时空上调节pH值微环境 具体的方式。如果做不到这一点，意味着决定细胞命运和功能的关键因素pH值不是 控制得很好。PI的长期目标是基于微环境pH的细胞功能闭环调节， 新陈代谢和形态发生。这一项目的总体目标，是迈向长期目标的关键一步，是 通过实时、空间选择性地调节pH值微环境来控制细胞。假设是该细胞 功能和行为可以用超高的时空分辨率(10-100µm；&lt；50 S)来调节，相比之下 到传统的、基于扩散的方法(&gt；103µm，&gt；103 S)，在受调节的pH微环境中 基于石墨烯的微电极纳米电化学研究 卓越的生物转导特性，解决了芯片上pH调节生命的主要挑战 用于典型微电极材料的电池系统。检验这一假设的方法是量化实时 模型细胞系统对双向阵列产生的阵列化pH微环境的响应 石墨烯-微电极换能器，光学透明，允许微观表征和 通过电信号询问和快速纳米电化学与蜂窝系统通信 微环境--pH调节。该项目将实现以下里程碑式的目标：(1)创建 研制双向石墨烯微电极阵列实现密集排列的pH微环境 传感器和(2)控制模型细胞系统(心肌细胞和肿瘤细胞)的功能和行为 通过使用石墨烯换能器阵列的时空微环境pH调制。PI是唯一的 由于PI的实验室有能力制造可集成的石墨烯微电极，因此能够实施该项目 在用于连接蜂窝系统、询问电/化学单元信号和控制的流体设备中 通过产生微尺度的pH梯度来表现细胞的行为。利用和组合这些技术可以使 用于选择性实时pH微环境的双向石墨烯传感器阵列的研制 调制和小区控制。该项目的预期成果是基于pH的电池控制工具，具有超过两个- 与传统方法相比，时空分辨率提高了数量级。这一结果是 对生物工程发展、再生医学和合成形态产生积极影响。

Microenvironmental pH is a key factor in cell functioning and pathogenesis. To control the function and behavior of cells by modulating pH microenvironments is critical to advancing the development of cell biology and tissue engineering and enabling applications in drug delivery and regenerative medicine. However, pH-based cell control remains a challenge due to the lack of means to real-time, spatioselective modulation of microenvironmental pH. While pH microenvironments in cell systems are highly heterogeneous in time and space, known pH-modulation methods are through CO2/HCO3− buffering and H+ diffusion, which are slow, isotropic, and nonspecific. An urgent need, therefore, is to modulate pH microenvironments in a spatiotemporally specific manner. Failure to do so means that pH, an essential factor that determines cell fate and function, is not in good control. The PI’s long-term goal is microenvironmental pH–based closed-loop regulation of cell function, metabolism, and morphogenesis. The overall goal of this project, a critical step towards the long-term goal, is to control cells by real-time, spatioselective modulation of pH microenvironments. The hypothesis is that cell function and behavior can be regulated with ultra-high spatiotemporal resolutions (10–100 µm, <50 s), compared to conventional, diffusion-based methods (>103 µm, >103 s), in pH microenvironments that are modulated nanoelectrochemically by microelectrodes based on graphene, a two-dimensional nanomaterial with unique outstanding bio-transduction properties that address the primary challenge of on-chip pH modulation of living cell systems for typical microelectrode materials. The approach to test this hypothesis is to quantify real-time responses of model cell systems to arrayed pH microenvironment generated by an array of bidirectional graphene-microelectrode transducers that are optically transparent to allow microscopic characterization and communicate with cellular systems through electrical signal interrogation and rapid nanoelectrochemical microenvironmental-pH modulation. The following milestone goals will be reached in this project: (1) to create densely arrayed pH microenvironment by developing an array of bidirectional graphene-microelectrode transducers and (2) to control the function and behavior of model cell systems (cardiomyocytes and tumor cells) via spatiotemporal microenvironmental pH modulation using the graphene transducer array. The PI is uniquely positioned to conduct the project due to the ability of the PI’s lab to create graphene microelectrodes integrable in a fluidic device for interfacing cellular systems, interrogating electrical/chemical cell signals, and controlling cell behavior by generating microscale pH gradients. To harness and combine these techniques allows the development of arrays of bidirectional graphene transducers for selective, real-time pH-microenvironment modulation and cell control. The expected outcome of the project is pH-based cell-control tools with over two- orders-of-magnitude enhanced spatiotemporal resolutions compared to conventional methods. This outcome is to generate positive impact on bioengineering development, regenerative medicine, and synthetic morphology.