摘要
The electrical penetration of the cell membrane is vital for determining the cell interior via impedance cytometry.Herein,we propose a method for determining the conductivity of the cell membrane through the tilting levels of impedance puises.When electrical penetration occurs,a high-frequency current freely passes through the cell membrane;thus,the intracellular distribution can directly act on the high-frequency impedance pulses.Numerical simulation shows that an uneven intracellular component distribution can affect the tilting levels of impedance pulses,and the tilting levels start increasing when the cell membrane is electrically penetrated.Experimental evidence shows that higher detection frequencies(>7 MHz)lead to a wider distribution of the tilting levels of impedance pulses when measuring cell populations with four-frequency impedance cytometry.This finding allows us to determine that a detection frequency of 7 MHz is able to pass through the membrane of Euglena gracilis(E.gracilis)cells.Additionally,we provide a possible application of four-frequency impedance cytometry in the biomass monitoring of single E.grailis cells.High-frequency impedance(≥7 MHz)can be applied to monitor these biomass changes,and low-frequency impedance(<7 MHz)can be applied to track the corresponding biovolume changes.Overall,this work demonstrates an easy determination method for the electrical penetration of the cell membrane,and the proposed platform is applicable for the multiparameter assessment of the cell state during cultivation.
基金
This work is supported by JSPS.Core-to-Core program
JSPS Grant-in-Aid for Scientific Research(No.20K15151)
Amada Foundation,Japan
Sasakawa Scientific Research Grant,Japan
NSG Foundation,Japan
White Rock Foundation,Japan
Austalian Research Council(ARC)Discovery Project(DP200102269),Australi
and the Nara Institute of Science and Technology Support Foundation,Japan
JST Support for Pioneering Research Initiated by the Next Generation program and Nara Institute of Science and Technology Touch stone program.