In this work, anchorage-dependent baby hamster kidney cells (BHK-21) were cultivated on microcarriers. Growth was monitored with off-line cell counts compared with on-line viable cell density monitoring based on permittivity. The two methods correlate with an R2of 0.99 in exponential phase. Therefore, permittivity-based viable cell density monitoring can be employed to reduce the effort and risks of off-line sampling. Learn More