A microarray biosensor that measures the electrical impedance of cell suspensions is presented. Single-cell–resolution measurement was facilitated by physically positioning individual cells on sensing electrodes by dielectrophoresis, obviating chemical or biological surface modification. The high-density (104 × 104) electrode array was incorporated with a complementary metal-oxide-semiconductor (CMOS) integrated chip (IC) to support impedance spectroscopy at frequencies ranging from 100 kHz to 1 MHz, achieving a rapid and cost-effective platform with a small form factor. Experiments with microbeads (10, 15, and 20 μm in diameter) and a live breast cancer cell line (MCF-7) have demonstrated that the developed prototype quantifies loaded microbeads or cells rapidly (<1 min), with a mapping accuracy over 95%, showing good agreement with optical observation. In addition, a new impedance model of a cancer cell suspended in buffer media was constructed to interpret the measurement results, and the simulation results obtained with the model showed good agreement with the experimental results.

提出了一种微阵列生物传感器，可测量细胞悬浮液的电阻抗。通过介电电泳将单个细胞物理定位在感应电极上，避免了化学或生物表面修饰，从而促进了单细胞分辨率的测量。高密度（104×104）电极阵列与互补金属氧化物半导体（CMOS）集成芯片（IC）集成在一起，以支持在100 kHz至1 MHz频率范围内的阻抗谱，从而实现了快速而经济的选择外形小巧的平台。用微珠（直径分别为10、15和20μm）和活乳腺癌细胞系（MCF-7）进行的实验表明，开发的原型可以快速（<1分钟）对加载的微珠或细胞进行定量，定位精度超过95 ％，与光学观察显示出良好的一致性。另外，构建了新的悬浮在缓冲液中的癌细胞阻抗模型来解释测量结果，并用该模型获得的仿真结果与实验结果吻合良好。