Methods of using pneumatic bioreactors

A method of growing a biological agent within a single use bioreactor, the method comprising the steps of:

• providing a containment vessel for holding biological contents, the containment vessel comprising a generally rectangular upper portion in horizontal section and a semi-cylindrical lower portion defining a semi-cylindrical concavity therewithin;
• providing a rotatable buoyancy-driven mixing device located within the containment vessel and having a substantially horizontal axis of rotation, the mixing device having a diameter such that when it rotates it substantially fills the semi-cylindrical concavity;
• sterilizing the containment vessel and the mixing device so that at least the interior of the containment vessel and the mixing device are sterile;
• providing a culture medium within the containment vessel;
• providing nutrients within the containment vessel to support growth of the biological agent within the culture medium;
• enclosing the containment vessel such that the culture medium is not exposed to the surrounding environment;
• rotating the mixing device about said horizontal axis to mix the contents of the containment vessel by introducing gas into the containment vessel at a location below the mixing device such that at least a portion of the gas rising within the containment vessel is temporarily captured by a portion of the mixing device to cause rotation of the mixing device due to the buoyancy of the captured gas;
• and
• discarding the containment vessel and mixing device after a single use of growing a biological agent.