Sampling retractor system and method of use

A sampling device for use in fixed-bed cell culture bioreactor systems comprising:

• A rotatable knob;
• an end cap including a hollow connector;
• a hollow retraction chamber having a first chamber end and a second chamber end, wherein the first chamber end is sealed against the rotatable knob, and the second chamber end is connected to, and in fluid communication with the end cap;
• a hollow tube having a tube first end and a tube second end, the tube first end connected to, and in fluid communication with the hollow connector of the end cap, and the tube second end configured for connection to a lid of a fixed-bed cell culture bioreactor system;
• a sampling element embedded inside the fixed-bed cell culture bioreactor system;
• and
• a retraction filament that connects the rotatable knob to the sampling element,
• wherein rotating the rotatable knob pulls the retraction filament and the sampling element in an upward direction through the hollow tube toward the rotatable knob and into the hollow retraction chamber.