Wang Min-Haw, Kao Min-Feng, Jang Ling-Sheng
Department of Electrical Engineering and Center for Micro/Nano Science and Technology, National Cheng Kung University, Taiwan.
Rev Sci Instrum. 2011 Jun;82(6):064302. doi: 10.1063/1.3594550.
This study presents an impedance measurement system for single-cell capture and measurement. The microwell structure which utilizes nDEP force is used to single-cell capture and a minimized impedance spectroscopy which includes a power supply chip, an impedance measurement chip and a USB microcontroller chip is used to single-cell impedance measurement. To improve the measurement accuracy of the proposed system, Biquadratic fitting is used in this study. The measurement accuracy and reliability of the proposed system are compared to those of a conventional precision impedance analyzer. Moreover, a stable material, latex beads, is used to study the impedance measurement using the minimized impedance spectroscopy with cell-trapping device. Finally, the proposed system is used to measure the impedance of HeLa cells and MCF-7 cells. The impedance of single HeLa cells decreased from 9.55 × 10(3) to 3.36 × 10(3) Ω and the impedance of single MCF-7 cells decreased from 3.48 × 10(3) to 1.45 × 10(3) Ω at an operate voltage of 0.5 V when the excitation frequency was increased from 11 to 101 kHz. The results demonstrate that the proposed impedance measurement system successfully distinguishes HeLa cells and MCF-7 cells.
本研究提出了一种用于单细胞捕获和测量的阻抗测量系统。利用介电泳力的微孔结构用于单细胞捕获，一种包括电源芯片、阻抗测量芯片和USB微控制器芯片的微型化阻抗谱用于单细胞阻抗测量。为提高所提系统的测量精度，本研究采用了双二次拟合。将所提系统的测量精度和可靠性与传统精密阻抗分析仪的进行了比较。此外，使用一种稳定的材料——乳胶珠，来研究使用带有细胞捕获装置的微型化阻抗谱进行阻抗测量。最后，所提系统用于测量HeLa细胞和MCF-7细胞的阻抗。当激励频率从11 kHz增加到101 kHz且工作电压为0.5 V时，单个HeLa细胞的阻抗从9.55×10³Ω降至3.36×10³Ω，单个MCF-7细胞的阻抗从3.48×10³Ω降至1.45×10³Ω。结果表明，所提阻抗测量系统成功区分了HeLa细胞和MCF-7细胞。
