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ABSTRACT Accurate cancer cell analysis is critical across a wide range of medical fields, including clinical diagnostics, personalized medicine, drug development, and cancer research. The ability to rapidly analyze and characterize cancer cells is key to understanding tumor characteristics, developing targeted therapies, and improving patient outcomes. Microscale electrokinetic (EK) techniques have demonstrated their effectiveness and reliability as powerful tools for cell analysis, including cancerous cells. The applications of dielectrophoresis (DEP), an EK technique, in cancer cell analysis are discussed here with a focus on carcinomas, cancer that develops in epithelial tissue. In this review article, the working mechanism of DEP is first introduced, followed by an in‐depth review of recent studies published between 2015 and 2024. The concluding remarks section provides a summary of the key points discussed in this review and offers insights into potential future advancements in DEP‐based systems for analyzing cancerous cells. 

Abstract The selective positioning and arrangement of distinct types of multiscale particles can be used in numerous applications in microfluidics, including integrated circuits, sensors and biochips. Electrokinetic (EK) techniques offer an extensive range of options for label‐free manipulation and patterning of colloidal particles by exploiting the intrinsic electrical properties of the target of interest. EK‐based techniques have been widely implemented in many recent studies, and various methodologies and microfluidic device designs have been developed to achieve patterning two‐ and three‐dimensional (3D) patterned structures. This review provides an overview of the progress in electropatterning research during the last 5 years in the microfluidics arena. This article discusses the advances in the electropatterning of colloids, droplets, synthetic particles, cells, and gels. Each subsection analyzes the manipulation of the particles of interest via EK techniques such as electrophoresis and dielectrophoresis. The conclusions summarize recent advances and provide an outlook on the future of electropatterning in various fields of application, especially those with 3D arrangements as their end goal. 

An empirical model predicts particle retention time in iEK devices by integrating linear and nonlinear EK effects. 

Nonlinear electrokinetic phenomena offer label-free, portable, and robust approaches for particle and cell assessment, including selective enrichment, separation, sorting, and characterization. The field of electrokinetics has evolved substantially since the first separation reports by Arne Tiselius in the 1930s. The last century witnessed major advances in the understanding of the weak-field theory, which supported developments in the use of linear electrophoresis and its adoption as a routine analytical technique. More recently, an improved understanding of the strong-field theory enabled the development of nonlinear electrokinetic techniques such as electrorotation, dielectrophoresis, and nonlinear electrophoresis. This review discusses the operating principles and recent applications of these three nonlinear electrokinetic phenomena for the analysis and manipulation of particles and cells and provides an overview of some of the latest developments in the field of nonlinear electrokinetics. 

Electrokinetic (EK) microsystems, which are capable of performing separations without the need for labeling analytes, are a rapidly growing area in microfluidics. The present work demonstrated three distinct binary microbial separations, computationally modeled and experimentally performed, in an insulator-based EK (iEK) system stimulated by DC-biased AC potentials. The separations had an increasing order of difficulty. First, a separation between cells of two distinct domains (Escherichia coli and Saccharomyces cerevisiae) was demonstrated. The second separation was for cells from the same domain but different species (Bacillus subtilis and Bacillus cereus). The last separation included cells from two closely related microbial strains of the same domain and the same species (two distinct S. cerevisiae strains). For each separation, a novel computational model, employing a continuous spatial and temporal function for predicting the particle velocity, was used to predict the retention time (tR,p) of each cell type, which aided the experimentation. All three cases resulted in separation resolution values Rs>1.5, indicating complete separation between the two cell species, with good reproducibility between the experimental repetitions (deviations < 6%) and good agreement (deviations < 18%) between the predicted tR,p and experimental (tR,e) retention time values. This study demonstrated the potential of DC-biased AC iEK systems for performing challenging microbial separations.