Reflection Coefficient S11 Related Measurement System for Label-Free Cell Seeding Analysis and Drug Testing in a Three-Dimensional (3D) Cell Culture Model

Abstract

Context: With regard to two-dimensional (2D) cell cultures in flat dishes, most of the three-dimensional (3D) cell cultures have advantages and gain importance in life sciences. But, their higher complexity requires adaptation of existing methods or different measurement systems in order to achieve accurate results. Bio-Impedance spectroscopy (Bio-IS) is a label- free and non-destructive method that is considered for analysis of 3D cell models. Purpose: We design a new Bio-IS measurement system for a 3D liver cell model to assess cell seeding and drug effects. Experiment Methods: We measured reflection coefficient S11 with differently (disc- and needle-like) shaped electrodes, which are in defined contact with the 3D liver cell model, metabolic activity (MTT test), and cytotoxicity (LDH assay). Results: We demonstrate that reflection coefficient S11 may be utilized to assess the 3D liver cell system in the frequency range of β-dispersion at 73 MHz only by means of the needle-like electrodes. This enables a reliable label-free and non-destructive determination of cell seeding and drug effects in the 3D liver cell culture model. The physical results have been verified by destructive biochemical methods (LDH and MTT assay). Conclusion: Our Bio-IS system for 3D liver cell models using needle-like electrodes enables label-ree and nondestructive determination of cell seeding and drug effects.