Dielectrophoresis (DEP) is widely utilized for trapping and sorting various types of cells, including live and dead cells and healthy and infected cells. This article focuses on the dielectric characterization of erythrocytes (red blood cells or RBCs) by quantifying DEP crossover frequency using a novel point-and-planar microwell device platform. Numerical simulations using COMSOL Multiphysics software demonstrate that the distribution of the DEP force is influenced by factors such as the shape of the point electrode, spacing between the point and planar electrodes, and the type of bioparticle being investigated.
View Article and Find Full Text PDFCoinfection with the tick-transmitted pathogen Babesia spp. is becoming a serious health problem because of the erythrocyte invasion through Ixodes scapularis tick. The transmission of this protozoan by blood transfusion often results in high morbidity and mortality in recipients.
View Article and Find Full Text PDFRare earth elements (REEs) are widely used across different industries due to their exceptional magnetic and electrical properties. In this work, Cupriavidus necator is characterized using dielectrophoretic ultra-high-frequency measurements, typically in MHz range to quantify the properties of cytoplasm in C. necator for its metal uptake/bioaccumulation capacity.
View Article and Find Full Text PDFThis work presents the dielectric characterization of rare earth elements (REEs) biosorption by Cupriavidus necator using dielectrophoretic crossover frequency measurements. Traditional means of characterizing biomass for biosorption is limited and time consuming. In this research we are presenting, for the first time, an electrokinetic method termed as dielectrophoresis (DEP) for the characterization of biosorption (uptake) of rare earth elements (REEs) by gram negative bacteria - Cupriavidus necator.
View Article and Find Full Text PDFThe 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.
View Article and Find Full Text PDFIt is a common practice in insulator-based dielectrophoretic separation to use and reuse PDMS-constructed microdevice for an extended period of time while performing biological and technical replicate experiments. This is usually done to rule out any effects of device variation on separation efficiency. Ensuring that all experimental conditions remain the same is critical to the conclusion that can be drawn from such repeated experiments.
View Article and Find Full Text PDFWe previously reported that inactivation of a universally conserved dimethyl adenosine transferase (KsgA) attenuates virulence and increases sensitivity to oxidative and osmotic stress in Salmonella Enteritidis. Here, we show a role of KsgA in cell-envelope fitness as a potential mechanism underlying these phenotypes in Salmonella. We assessed structural integrity of the cell-envelope by transmission electron microscopy, permeability barrier function by determining intracellular accumulation of ethidium bromide and electrophysical properties by dielectrophoresis, an electrokinetic tool, in wild-type and ksgA knock-out mutants of S.
View Article and Find Full Text PDFBabesia species are obligate intraerythrocytic tick-borne protozoan parasites that are the etiologic agents of babesiosis, a potentially life-threatening, malaria-like illness in humans and animals. Babesia-infected people have been known to suffer from complications including liver problems, severe hemolytic anemia, and kidney failure. As reported by the Food and Drug Administration, 38% of mortality cases observed in transfusion recipients were associated with transfusion transmitted diseases of which babesiosis is the chief culprit.
View Article and Find Full Text PDFDielectrophoresis is a powerful technique used to distinguish distinct cellular identities in heterogeneous cell populations and to monitor changes in the cell state without the need for biochemical tags, including live and dead cells. Recent studies in the past decade have indicated that dielectrophoresis can be used to discriminate the disease state of cells by exploring the differences in the dielectric polarizabilities of the cells. Factors controlling the dielectric polarizability are dependent on the conductivity and permittivity of the cell and the suspending medium, the cell morphology, the internal structure, and the electric double layer effects associated with the charges on the cell surface.
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