Department Nano Device Technology, Fraunhofer Institute for Electronic Nano Systems, Technologie-Campus 3, 09126 Chemnitz, Germany.
Material Systems for Nanoelectronics, Chemnitz University of Technology, 09126 Chemnitz, Germany.
Biosensors (Basel). 2020 Jul 23;10(8):82. doi: 10.3390/bios10080082.
We counted bacterial cells of strain K12 in several-microliter DI water or in several-microliter PBS in the low optical density (OD) range (OD = 0.05-1.08) in contact with the surface of Si-based impedance biochips with ring electrodes by impedance measurements. The multiparameter fit of the impedance data allowed calibration of the impedance data with the concentration c of the cells in the range of c = 0.06 to 1.26 × 10 cells/mL. The results showed that for in DI water and in PBS, the modelled impedance parameters depend linearly on the concentration of cells in the range of c = 0.06 to 1.26 × 10 cells/mL, whereas the OD, which was independently measured with a spectrophotometer, was only linearly dependent on the concentration of the cells in the range of c = 0.06 to 0.50 × 10 cells/mL.
我们通过阻抗测量，在与基于硅的带有环形电极的阻抗生物芯片表面接触的情况下，在低光密度（OD）范围内（OD=0.05-1.08），对 DI 水中或 PBS 中的 K12 菌株的细菌细胞进行了计数，其数量为几微升。通过对阻抗数据的多参数拟合，我们可以将阻抗数据与细胞浓度 c 进行校准，细胞浓度 c 的范围为 c=0.06 到 1.26×10 个细胞/mL。结果表明，对于 DI 水中和 PBS 中的，模型化的阻抗参数与细胞浓度 c 在 0.06 到 1.26×10 个细胞/mL 的范围内呈线性关系，而 OD 值则与分光光度计独立测量的结果一致，OD 值仅在细胞浓度 c 在 0.06 到 0.50×10 个细胞/mL 的范围内呈线性关系。
