miniPERM® bioreactors feature two compartments separated by a dialysis membrane for production of concentrated cell products of several mg/mL and biomass of more than 107 cells/mL in small volumes. A nutrient module with membrane-vented cap serves as the media reservoir with a capacity of 550 mL. A production module, available in three volumes for suspension cells and an option for adherent cells, serves as the culture chamber with an outer gas-permeable silicone membrane.