have a working volume in the mililiter-scale and are recommended for screening. They work with single-use microwell plates and cassettes or rigid plastic vessels into which optical sensors (e.g. for the measurement of pH, temperature and dissolved oxygen) can be integrated. Microbioreactors are mechanically driven and are run either in incubators that control the gas input and the mechanical energy input 53, 54 or have their own measuring, control and monitoring unit. Examples for automated microbioreactors are the ambr15 and ambr250 (Sartorius Stedim Biotech), the BioBLU 0.3-systems made by Eppendorf (see CElliGen BLU bioreactors), the Micro-24 bioreactor system (Pall Life Sciences), the micro-Matrix (Applikon) and the Biolector (mp2-labs).