Adekanmbi Ezekiel O, Giduthuri Anthony T, Srivastava Soumya K
Department of Chemical and Materials Engineering, University of Idaho, Moscow, ID 83844-1021, USA.
Micromachines (Basel). 2020 Mar 25;11(4):340. doi: 10.3390/mi11040340.
The dielectrophoretic separation of infiltrating ductal adenocarcinoma cells (ADCs) from isolated peripheral blood mononuclear cells (PBMCs) in a ~1.4 mm long Y-shaped microfluidic channel with semi-circular insulating constrictions is numerically investigated. In this work, ADCs (breast cancer cells) and PBMCs' electrophysiological properties were iteratively extracted through the fitting of a single-shell model with the frequency-conductivity data obtained from AC microwell experiments. In the numerical computation, the gradient of the electric field required to generate the necessary dielectrophoretic force within the constriction zone was provided through the application of electric potential across the whole fluidic channel. By adjusting the difference in potentials between the global inlet and outlet of the fluidic device, the minimum (effective) potential difference with the optimum particle transmission probability for ADCs was found. The radius of the semi-circular constrictions at which the effective potential difference was swept to obtain the optimum constriction size was also obtained. Independent particle discretization analysis was also conducted to underscore the accuracy of the numerical solution. The numerical results, which were obtained by the integration of fluid flow, electric current, and particle tracing module in COMSOL v5.3, reveal that PBMCs can be maximally separated from ADCs using a DC power source of 50 V. The article also discusses recirculation or wake formation behavior at high DC voltages (>100 V) even when sorting of cells are achieved. This result is the first step towards the production of a supplementary or confirmatory test device to detect early breast cancer non-invasively.
对在一个约1.4毫米长、带有半圆形绝缘缩窄的Y形微流控通道中，从分离出的外周血单个核细胞（PBMC）中进行浸润性导管腺癌细胞（ADC）的介电泳分离进行了数值研究。在这项工作中，通过将单壳模型与从交流微孔实验获得的频率-电导率数据进行拟合，迭代提取了ADC（乳腺癌细胞）和PBMC的电生理特性。在数值计算中，通过在整个流体通道上施加电势，提供了在缩窄区域内产生必要介电泳力所需的电场梯度。通过调整流体装置全局入口和出口之间的电势差，找到了对于ADC具有最佳粒子传输概率的最小（有效）电势差。还获得了扫描有效电势差以获得最佳缩窄尺寸时的半圆形缩窄半径。还进行了独立粒子离散化分析以强调数值解的准确性。通过在COMSOL v5.3中集成流体流动、电流和粒子追踪模块获得的数值结果表明，使用50 V的直流电源可以最大程度地将PBMC与ADC分离。本文还讨论了即使在实现细胞分选时，在高直流电压（>100 V）下的再循环或尾流形成行为。这一结果是朝着生产用于非侵入性检测早期乳腺癌的补充或验证测试设备迈出的第一步。
