Biomanufacturing Research Institute and Technology Enterprises-BRITE and Department of Pharmaceutical Sciences, North Carolina Central University, Durham, NC 27707, USA.
Biomed Microdevices. 2011 Dec;13(6):1075-88. doi: 10.1007/s10544-011-9577-8.
In this study, electric/electrochemical impedance spectroscopy and cyclic voltammetry were used to study the cellular activities of oral cancer cell line CAL 27, including the kinetics of cell adhesion, spreading, and cell proliferation on interdigitated microelectrodes (IMEs). Impedance spectra of CAL 27 cells on IMEs electrodes were obtained in cell growth medium and in 0.1 M PBS with 50 mM [Fe(CN)₆]³⁻/⁴⁻ as redox probe. Equivalent circuits were used to model both cases. In cell growth medium, impedance spectra allowed us to analyze the changes in capacitance and resistance due to cell attachment on the IMEs over the entire experiment period. It was found that cell spreading caused the most significant decrease in capacitance component and slight increase in resistance component. Impedance change at given frequencies (between 10 kHz to 100 kHz) was found to be linearly increased with increasing cell number of CAL 27 on the IMEs. In comparison with non-cancer oral epithelial cells (Het-1A), at equal cell number, cancer cells always generated impedance several folds higher than that of non-cancer cells. In the presence of [Fe(CN)₆]³⁻/⁴⁻, impedance spectra allowed us to analyze the change in electron transfer resistance of IMEs due to cell attachment, in which an increase trend was observed at 24 h with increasing cell number from 2500 cells to 10,000 cells on IMEs. Double layer capacitance was also affected by cell attachment, and a decrease in double layer capacitance was observed with increasing cell number on the electrodes. Cyclic voltammetric measurements correlated well with the impedance results. The results of this study demonstrated the use of electrochemical approaches to obtain and understand cellular behaviors/activities of oral cancer cells, potentially providing useful tools for cancer cell research.
在这项研究中，我们使用了电化学阻抗谱和循环伏安法来研究口腔癌细胞系 CAL 27 的细胞活性，包括细胞黏附、铺展和增殖的动力学过程，这些过程发生在叉指微电极（IMEs）上。我们在细胞生长培养基和含有 50 mM [Fe(CN)₆]³⁻/⁴⁻作为氧化还原探针的 0.1 M PBS 中获得了 CAL 27 细胞在 IMEs 电极上的阻抗谱。我们使用等效电路来模拟这两种情况。在细胞生长培养基中，阻抗谱允许我们分析整个实验期间由于细胞附着在 IMEs 上而导致的电容和电阻的变化。结果发现，细胞铺展导致电容分量显著减小，电阻分量略有增加。在给定频率（10 kHz 至 100 kHz 之间）下的阻抗变化被发现随着 CAL 27 细胞在 IMEs 上数量的增加而呈线性增加。与非癌口腔上皮细胞（Het-1A）相比，在相同的细胞数量下，癌细胞产生的阻抗总是比非癌细胞高几个数量级。在存在[Fe(CN)₆]³⁻/⁴⁻的情况下，阻抗谱允许我们分析由于细胞附着导致的 IMEs 电子转移电阻的变化，结果发现，随着细胞数量从 2500 个增加到 10000 个，24 小时时的电阻呈上升趋势。双电层电容也受到细胞附着的影响，随着电极上细胞数量的增加，双电层电容减小。循环伏安测量与阻抗结果很好地相关。本研究的结果表明，电化学方法可用于获得和理解口腔癌细胞的细胞行为/活性，为癌细胞研究提供了有用的工具。
