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Round-tip dielectrophoresis-based tweezers for single micro-object manipulation
Taiga Kodama1, Toshihisa Osaki, Ryuji Kawano
1Kanagawa Academy of Science and Technology, KSP EAST 303, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa 213-0012, Japan.
Biosensors & Bioelectronics
|April 11, 2013
Summary
This study introduces novel dielectrophoresis tweezers for precise micro-object manipulation. These tweezers effectively handle delicate, transparent liposomes and separate labeled cells, offering a new tool for biomanipulation.
Area of Science:
- Biophysics
- Microfluidics
- Nanotechnology
Background:
- Manipulating micro-objects like liposomes and cells is challenging due to their transparency and fragility.
- Conventional methods like optical tweezers and micropipettes have limitations with such delicate samples.
Purpose of the Study:
- To develop an efficient methodology for single micro-object manipulation using dielectrophoresis (DEP) tweezers.
- To demonstrate the capability of DEP tweezers in handling cell-sized liposomes and separating biological cells.
Main Methods:
- Fabrication of round-tip DEP tweezers using a glass needle and gold electrodes.
- Utilizing positive dielectrophoresis (pDEP) to trap and move micro-objects.
- Applying Stokes' drag theory to experimentally validate pDEP force calculations.
Main Results:
- Successfully captured, conveyed, and positioned single cell-sized liposomes (5-23µm).
- Demonstrated the separation of labeled single cells from non-labeled cells.
- Experimental results for pDEP force aligned with theoretical predictions based on liposome size, media content, and applied AC voltage/frequency.
Conclusions:
- Round-tip DEP tweezers provide an efficient method for precise manipulation of transparent and flexible biological micro-objects.
- This technology overcomes limitations of conventional methods for handling delicate micro-samples.
- The developed tweezers offer a valuable tool for applications in cell sorting and biomanipulation.
