Analysis of Electric Fields inside Microchannels and Single Cell Electrical Lysis with a Microfluidic Device

Abstract

Analysis of electric fields generated inside the microchannels of a microfluidic device for electrical lysis of biological cells along with experimental verification are presented. Electrical lysis is the complete disintegration of cell membranes, due to a critical level of electric fields applied for a critical duration on a biological cell. Generating an electric field inside a microchannel of a microfluidic device has many advantages, including the efficient utilization of energy and low-current requirement. An ideal microchannel model was compared with a practical microchannel model using a finite element analysis tool that suggests that the overestimation error can be over 10%, from 2.5 mm or smaller, in the length of a microchannel. Two analytical forms are proposed to reduce this overestimation error. Experimental results showed that the high electric field is confined only inside the microchannel that is in agreement with the simulation results. Single cell electrical lysis was conducted with a fabricated microfluidic device. An average of 800 V for seven seconds across an 8 mm-long microchannel with the dimension of 100 μm × 20 μm was required for lysis, with electric fields exceeding 100 kV/m and consuming 300 mW.

Control of molecular shuttles by designing electrical and mechanical properties of microtubules

“…The microfluidic device was designed on the basis of the measured R MT values: 40.3 mm (n = 90) for MT-2, 21.0 mm (n = 57) for MT-5, and 14.5 mm (n = 39) for MT-5′, all under 5.3 kV m −1 . We considered three points for defining the dimensions of the device: (i) The separation channel needs to have a width of <1 mm to obtain a uniform electric field (48); (ii) the cross-contamination should be decreased by increasing the difference of R MT to be used as a molecular sorter; (iii) to observe the MT separation in the field of view, the travel distance in the y direction of either MT group should be less than 80 mm. Because Eq.…”

Sorting of molecular shuttles by designing electrical and mechanical properties of microtubules

“…Device design and MT sorting. The microfluidic device was designed based on the measured RMT values: 40.3 µm (n = 90) for MT-2, 21.0 µm (n = 57) for MT-5, and 14.5 µm (n = 39) for MT-5′ under 5.3 kV m −1 .Here, three points were considered to define the dimensions of the device: (1) the separation channel needs to be <1 mm width to obtain a uniform electric field;48 (2) the cross-contamination should be decreased by increasing the difference of RMT to be used as a molecular sorter; (3) to observe MT separation in a field of view, the travel distance in the y-direction of either MT group should be less than 80 µm. As equation(2)suggests the difference in RMT is inversely proportional to the field intensity, we recalculated RMT with a field intensity of 3 kV m −1 , and the MT trajectories were predicted with equation(1); travelling distances in the ydirection were 84.6 µm for MT-2, 58.8 µm for MT-5, and 35.2 µm for MT-5′ at x = 70 µm (Supplementary Fig.…”

Analysis of Planar Circular Interdigitated Electrodes for Electroporation

“…Analytical approximations introduce additional parameter control and improved prototyping capabilities in the development of microchannels and electrolysis devices [19,20].…”