BioMEMS Research Group, Tecnológico de Monterrey, Campus Monterrey, Monterrey, Mexico.
Electrophoresis. 2011 Sep;32(18):2502-11. doi: 10.1002/elps.201100168. Epub 2011 Aug 19.
Dielectrophoresis (DEP) is the motion of particles due to polarization effects in nonuniform electric fields. DEP has great potential for handling cells and is a non-destructive phenomenon. It has been utilized for different cell analysis, from viability assessments to concentration enrichment and separation. Insulator-based DEP (iDEP) provides an attractive alternative to conventional electrode-based systems; in iDEP, insulating structures are used to generate nonuniform electric fields, resulting in simpler and more robust devices. Despite the rapid development of iDEP microdevices for applications with cells, the fundamentals behind the dielectrophoretic behavior of cells has not been fully elucidated. Understanding the theory behind iDEP is necessary to continue the progress in this field. This work presents the manipulation and separation of bacterial and yeast cells with iDEP. A computational model in COMSOL Multiphysics was employed to predict the effect of direct current-iDEP on cells suspended in a microchannel containing an array of insulating structures. The model allowed predicting particle behavior, pathlines and the regions where dielectrophoretic immobilization should occur. Experimental work was performed at the same operating conditions employed with the model and results were compared, obtaining good agreement. This is the first report on the mathematical modeling of the dielectrophoretic response of yeast and bacterial cells in a DC-iDEP microdevice.
介电泳（DEP）是由于非均匀电场中的极化效应而导致颗粒的运动。DEP 在处理细胞方面具有很大的潜力，是一种非破坏性的现象。它已被用于不同的细胞分析，从生存力评估到浓度富集和分离。基于绝缘体的 DEP（iDEP）为传统的基于电极的系统提供了一种有吸引力的替代方案；在 iDEP 中，使用绝缘结构来产生非均匀电场，从而产生更简单、更坚固的器件。尽管基于 iDEP 的微器件在细胞应用方面发展迅速，但细胞的介电泳行为背后的基本原理尚未完全阐明。了解 iDEP 的理论对于继续该领域的进展是必要的。本工作展示了使用 iDEP 对细菌和酵母细胞的操纵和分离。在 COMSOL Multiphysics 中使用计算模型来预测直流-iDEP 对悬浮在包含一系列绝缘结构的微通道中的细胞的影响。该模型允许预测颗粒行为、轨迹线以及应该发生介电泳固定的区域。在与模型相同的工作条件下进行了实验工作，并对结果进行了比较，得到了很好的一致性。这是首次报道在直流-iDEP 微器件中酵母和细菌细胞的介电泳响应的数学建模。
