Single-Cell Trapping and Manipulations with Bipolar Electrodes

 描述：少数细胞的意想不到的反应会对疾病的发展、预后和治疗产生重大影响。例如，在癌症的治疗中，侵袭性的、亚克隆性的恶性细胞谱系的存活和复苏也不例外。然而，我们才刚刚开始发现这些现象和潜在的生物机制，因为它们在大范围内是模糊的。检测罕见的表型或细胞反应可能需要分析数千个单个细胞。为了满足这一需求，我们建议开发一种基于介电泳法(DEP)的设备，使用廉价和简单的组件以阵列形式获得少量或单细胞捕获的高产率。具体地说，我们建议使用双极电极(BPES)上的离子贫化和富集化来产生用于基于阵列的细胞捕获的窄电场极大值和极小值的阵列。这一技术发展具有重大意义，因为1)它满足了对有效和廉价的单细胞操作的需求，2)离子富集区和贫穷区提供了具有可调大小和位置的强电场梯度(强DEP力)，3)BPES的使用允许方便地排列。DEP是一种多功能和强大的技术，最近得到了越来越多的使用，包括商业技术。DEP可用于运输、分拣、捕获和过滤细胞，无需细胞标签或昂贵的组件，并已扩展到单细胞阵列捕获。尽管有这些主要优点，但目前的DEP技术仍有一些挑战需要克服，其中最严重的三个缺点与DEP力所需的电场梯度的产生有关。首先，虽然DEP技术可以并行运行，但要实现一系列局部电场梯度，存在实际障碍。其次，在这些电极和绝缘屏障周围存在的DEP力的范围可能太短，不适合高通量器件操作。第三，也是最后一点，这些策略产生的电场的大小和位置是固定的，缺乏可塑性。在这里，我们建议通过在BPE阵列上富集和耗尽法拉第离子来局部控制DEP介质的导电性来塑造电场。该技术具有以下独特的优点：1)由于陡峭的电场梯度和对DEP介质复介电常数的协同效应，离子贫化和富集区将在捕获位置周围产生强大的DEP力；2)这些电场梯度可以比传统的DEP电极阵列产生的电场梯度延伸到电极更远的地方；3)可以通过流体流动来移动捕获位置。

 DESCRIPTION: An unexpected response from a minority of cells can have a dramatic impact on the development, prognosis, and treatment of disease. For example, in the treatment of cancer, the survival and resurgence of an aggressive, subclonal lineage of the malignant cells is not exceptional. Yet, we are only just beginning to uncover these phenomena and the underlying biological mechanisms because they are obscured at the bulk scale. Detection of a rare phenotype or cellular response can require the analysis of thousands of individual cells. To address this need, we propose to develop a dielectrophoresis (DEP)-based device with a high yield of few- or single-cell capture in an array format using inexpensive and simple components. Specifically, we propose to use ion depletion and enrichment at bipolar electrodes (BPEs) to generate an array of narrow electric field maxima and minima for array-based cell capture. This technological development is significant because 1) it addresses a need for effective and inexpensive single-cell manipulation, 2) the ion enrichment and depletion zones provide strong electric field gradients (strong DEP force) having a tunable size and location, 3) the use of BPEs allows facile arraying. DEP is a versatile and powerful technique that has grown in use recently to include commercial technology. DEP can be used to transport, sort, trap, and filter cells without cell labels or expensive components and has been extended to single-cell arrayed capture. Despite these major advantages, current DEP technologies have remaining challenges to overcome, and three of the most serious shortcomings relate to the generation of the electric field gradient required for DEP force. First, while DEP technologies can be operated in parallel, there are practical barriers to achieving an array of local electric field gradients. Second, the range over which DEP force exists around these electrodes and insulating barriers can be too short for high throughput device operation. Third and finally, the size and location of the electri field produced by each of these strategies is fixed, lacking plasticity. Here, we propose to shape the electric field using localized control of the conductivity of the DEP medium via faradaic ion enrichment and depletion at an array of BPEs. The proposed technology has the following unique advantages: 1) the ion depletion and enrichment zones will generate strong DEP force around the trapping locations owing to steep electric field gradients and a synergistic effect on the complex permittivity of the DEP medium, 2) these electric field gradients can extend further from the electrodes than those generated by traditional DEP electrode arrays, 3) the trapping location can be mobilized using fluid flow.