Live Jurkat cells were trapped by dielectrophoresis on a coplanar waveguide and the resulted changes in its reflection and transmission coefficients were measured from 900 Hz to 40 GHz. The measurement confirms that the decrease of nucleus size in a cell increases its impacts on both the reflection and transmission coefficients. Being fast, compact and label free, broadband electrical sensing may be used to detect other changes of the nucleus morphology and DNA content, which could be useful for cancer diagnosis.
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Broadband Electrical Sensing of a Live Biological Cell with In Situ Single-Connection Calibration
Single-connection in situ calibration using biocompatible solutions is demonstrated in single-cell sensing from 0.5 to 9 GHz. The sensing is based on quickly trapping and releasing a live cell by dielectrophoresis on a coplanar transmission line with a little protrusion in one of its ground electrodes. The same transmission line is used as the calibration standard when covered by various solutions of known permittivities. The results show that the calibration technique may be precise enough to differentiate cells of different nucleus sizes, despite the measured difference being less than 0.01 dB in the deembedded scattering parameters. With better accuracy and throughput, the calibration technique may allow broadband electrical sensing of live cells in a high-throughput cytometer.
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- Award ID(s):
- 1809623
- PAR ID:
- 10231274
- Date Published:
- Journal Name:
- Sensors
- Volume:
- 20
- Issue:
- 14
- ISSN:
- 1424-8220
- Page Range / eLocation ID:
- 3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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