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2. THICK-ELECTRODE DEP FOR SINGLE-CELL 3D ROTATION
2.5 EXPERIMENTAL SETUP
2.5.1 EXPERIMENTAL EQUIPMENT
e main equipment includes: four-channel arbitrary waveform generator (TGA-12104, TTi) that
the signal frequency range is from 0–25 MHz, and the amplitude range is from 0–20 Vp-p, mi-
cropump (Legato 200, KD Scientic), inverted microscope (Nikon Ti-U); CCD camera (acA640-
120gm, Basler, 30–100 frames/s). A homemade Labview software controls the switching of signal
conguration and real-time video acquisition of the CCD camera.
2.5.2 SIGNAL CONFIGURATION
Table 2.1 shows the signal congurations of each electrode in dierent working modes.
Table 2.1 Electrical signal conguration of cell loading and 3D rotation mode
Electrodes 1 2 3 4 Bottom
Cell loading Float Float 0 π Float
X-axis rotation (+)
0 4π/3 4π/3 0 2π/3
X-axis rotation (–)
4π/3 0 0 4π/3 2π/3
Y-axis rotation (+)
0 0 4π/3 4π/3 2π/3
Y-axis rotation (–)
4π/3 4π/3 0 0 2π/3
Z-axis rotation (+)
0 π/2 π 3π/2
Float
Z-axis rotation (–)
3π/2 π π/2 0
Float
2.5.3 EXPERIMENTAL METHODS
Eect of electrical signal parameters
In order to generate a horizontal rotational electric eld in the thick-electrode multi-electrode
structure, it is only necessary to apply signal with the same amplitude and frequency, but with phase
shift of 90° on the four thick electrodes. For out-of-plane rotation, the vertical rotational electric
eld needs to be formed by using thick electrodes in combination with the bottom electrode. Since
the electrode structure is asymmetrically distributed in the vertical direction, the electric eld
strength in one signal period is not the same.
ere is a dierence in the strength of the rotational electric eld generated by the dierent
phase shifts in the out-of-rotation mode. In order to determine the optimal value of the phase shift,
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