The main intention of this work is the continuous and automatical monitoring of the growth of a cell culture (cell density, viability) in addition to using common online parameters (e.g. pH, pO2) as indicators for the culture condition. The combination of these two components results in a much more complete picture of the cell culture. To achieve this goal the sampling and the subsequent sample management of mammalian cell cultures in pilot scale was automated by using an autonomous service robot.
Automation of the sampling procedure requires additional devices that perform operations, such as sampling the bioreactor, pipetting the sample, counting the cells with an automated cell counter and more. As one of the main components a reactor-connected sampling device which allows repeated sterile sampling into a vial was developed. At a given time the sampling is started automatically. The culture broth flow is divided into flushing and sampling. After the sampling the system is purged and steam sterilized and ready for the next cycle.
Linking of the different operations is performed with an autonomous service robot. The robot consists of an industrial robot arm which is mounted on a mobile platform. To enable the service robot to perform the given tasks it is equipped with several sensors. Laser scanners are used for navigation in the laboratory, whereas a color camera in combination with a force/torque sensor are used to perform operations related to handling the sample vial.
The device control system coordinates the sampling sequence and interaction between the devices and the robot. Additionally collected data and conditional parameters are stored and handed over to the process control system where the results are presented together with the online data.