Dielectrophoresis Prototypic Polystyrene Particle Synchronization toward Alive Keratinocyte Cells for Rapid Chronic Wound Healing

Abstract

Diabetes patients are at risk of having chronic wounds, which would take months to years to resolve naturally. Chronic wounds can be countered using the electrical stimulation technique (EST) by dielectrophoresis (DEP), which is label-free, highly sensitive, and selective for particle trajectory. In this study, we focus on the validation of polystyrene particles of 3.2 and 4.8 μm to predict the behavior of keratinocytes to estimate their crossover frequency (fXO) using the DEP force (FDEP) for particle manipulation. MyDEP is a piece of java-based stand-alone software used to consider the dielectric particle response to AC electric fields and analyzes the electrical properties of biological cells. The prototypic 3.2 and 4.8 μm polystyrene particles have fXO values from MyDEP of 425.02 and 275.37 kHz, respectively. Fibroblast cells were also subjected to numerical analysis because the interaction of keratinocytes and fibroblast cells is essential for wound healing. Consequently, the predicted fXO from the MyDEP plot for keratinocyte and fibroblast cells are 510.53 and 28.10 MHz, respectively. The finite element method (FEM) is utilized to compute the electric field intensity and particle trajectory based on DEP and drag forces. Moreover, the particle trajectories are quantified in a high and low conductive medium. To justify the simulation, further DEP experiments are carried out by applying a non-uniform electric field to a mixture of different sizes of polystyrene particles and keratinocyte cells, and these results are well agreed. The alive keratinocyte cells exhibit NDEP force in a highly conductive medium from 100 kHz to 25 MHz. 2D/3D motion analysis software (DIPP-MotionV) can also perform image analysis of keratinocyte cells and evaluate the average speed, acceleration, and trajectory position. The resultant NDEP force can align the keratinocyte cells in the wound site upon suitable applied frequency. Thus, MyDEP estimates the Clausius–Mossotti factors (CMF), FEM computes the cell trajectory, and the experimental results of prototypic polystyrene particles are well correlated and provide an optimistic response towards keratinocyte cells for rapid wound healing applications.

Effect of microfluidic rectangular microelectrode geometry on bioparticles manipulation in dielectrophoretic application

“…However, the electric field gradient remained unchanged to the increase of applied frequency. Although the frequency has not contributed to the electric field gradient but note that it is still an important factor that influence the particle, as the particle DEP response is highly dependent on applied frequency and which is governed by the equation (2) and equation ( 3) 11 . This result has shown that the applied voltage has a substantial influence on the electric field gradient, however the applied frequency will have no effect on the electric field gradient.…”

Wound Healing with Electrical Stimulation Technologies: A Review

“…TAMA work led to the identification of a tapered side wall between 60 and 70 degrees for the generation of a more uniform electric field from two spots at top and bottom edges of the tapered microelectrodes [161]. Refinement of the TAMA work concluded that 65 degrees was the best reading in TAMA to generate dielectrophoretic force for lateral and vertical manipulation of particle manipulation as shown in Figure 5b [164]. A DEP study on keratinocytes using "MyDEP" software showed that the DEP response of keratinocytes was successfully simulated by using polystyrene particles [164].…”

“…Refinement of the TAMA work concluded that 65 degrees was the best reading in TAMA to generate dielectrophoretic force for lateral and vertical manipulation of particle manipulation as shown in Figure 5b [164]. A DEP study on keratinocytes using "MyDEP" software showed that the DEP response of keratinocytes was successfully simulated by using polystyrene particles [164]. This is of interest, as DEP targeted specific cells and hence, the mobilisation of keratinocytes in an appropriate direction, and the plane will make re-epithelisation possible, especially in the case of a chronic wound with sufficient granulation but slow or no opposing wound edges.…”

Integration of a Dielectrophoretic Tapered Aluminum Microelectrode Array with a Flow Focusing Technique

“…A TAMA consists of an aluminum microelectrode array on a silicon substrate and is fabricated based on the CMOS processing technique [ 27 , 28 ]. Based on the investigation from our previous studies, the F DEP produced by this microelectrode produced a higher gradient non-uniform electrical field from the top and bottom edges of the microelectrode [ 29 , 30 ]. It managed to separate and isolate more than one type of particle depending on the F DEP acting on the particles by adjusting the frequency of the electrical field.…”