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Updated: Nov 10, 2025
09:18
Measurement of Extracellular Ion Fluxes Using the Ion-selective Self-referencing Microelectrode Technique
Published on: May 3, 2015
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Effect of Electrolyte Concentration on Cell Sensing by Measuring Ionic Current Waveform through Micropores
Kazumichi Yokota1, Muneaki Hashimoto1, Kazuaki Kajimoto1
1National Institute of Advanced Industrial Science and Technology, Takamatsu, Kagawa 761-0395, Japan.
Biosensors
|April 3, 2021
Summary
The resistive pulse method (RPM) accurately distinguishes cancer cells from leukocytes by measuring cell size, deformability, and surface charge. Optimizing electrolyte concentration improved discrimination accuracy, showing RPM
Area of Science:
- Biomedical Engineering
- Cell Biology
- Oncology
Background:
- Immunostaining is common for blood cancer cell detection but risks missing cells due to variable protein expression.
- Accurate quantification of circulating tumor cells (CTCs) is crucial for cancer prognosis and treatment monitoring.
Purpose of the Study:
- To develop and validate the resistive pulse method (RPM) for accurate discrimination of cancer cells from leukocytes.
- To assess the impact of electrolyte concentration on RPM's ability to differentiate cell types based on biophysical properties.
Main Methods:
- Utilized the resistive pulse method (RPM) to measure ionic current changes as individual cells passed through a micro-constriction.
- Analyzed pulse signal height and shape to determine cell size, deformability, and surface charge.
- Compared RPM performance using different electrolyte concentrations (1.0x PBS vs. 0.5x PBS with glucose).
Main Results:
- Accurate cancer cell discrimination was not achieved with standard 1.0x PBS.
- Using 0.5x PBS with 2.77% glucose, RPM achieved accurate discrimination with a low error rate of 4.5 ± 0.5%.
- RPM successfully measured individual cell size, deformability, and surface charge.
Conclusions:
- The resistive pulse method (RPM) offers a promising approach for accurate cancer cell detection in blood.
- Optimizing electrolyte conditions is critical for enhancing RPM's sensitivity and specificity in distinguishing cancer cells from leukocytes.
- RPM's ability to assess multiple biophysical parameters provides a robust method for circulating tumor cell analysis.
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