Systems and methods for viral transfection of cells in a bioreactor

A system for transfecting cells to produce a selected virus, the system comprising:

• a first fluid delivery device configured to contain and deliver a first solution comprising extrachromosomal DNA molecules encoding the virus;
• a second fluid delivery device configured to contain and deliver a second solution comprising a transfection agent;
• a first fluid delivery channel fluidically coupled to the first and second fluid delivery devices;
• at control valve fluidically coupled to at least one of the first and second fluid delivery devices and the first fluidic delivery channel, the control valve configured to control flow between the first and second fluid delivery devices and outward flow from one or both of the fluid deliver devices to another fluid delivery channel;
• a second fluid delivery channel fluidically coupled to the at least one control valve, the second fluid delivery channel configured to be fluidically coupled to a bioreactor vessel, the bioreactor vessel configured to contain the cells to be transfected;
• and
• a controller operatively to the control valve, the controller configured to control flow between the first and second chambers and flow from at least one of the first and second chambers to the second fluid delivery channel.