Bio-burden: This test involves eluting a device in sterile media which will remove bacterial/fungal cells and endospores. The eluent is then tested to confirm the cell/spore numbers. Bio-burden is largely performed to ensure the background microbial contamination level isn’t so high it would challenge the sterilisation process.
Endotoxin: This test involves eluting a device in pyrogen-free water and then analysing via either the gel-clot or kinetic turbidimetric method. Endotoxin analysis is performed to ensure that the device doesn’t contain high levels of bacterial pyrogens, which can cause a pyrogenic shock if they enter a patient’s bloodstream.
Sterility: This test involves submerging a sterile device into laboratory broth which is performed inside a specially designed isolator suite. Sterility analysis confirms that your sterilisation method has been able to sterilise the device effectively or that your sterility barrier (pouch/bag etc) can maintain sterility.
Cytotoxicity: This test involves eluting a device in specialised media and then adding it into a human-natured cell line. A spectrophotometer is then used to assess the quantity of cell death. Cytotoxicity is performed to ensure that a device (when it encounters a patient) doesn’t cause cellular damage.
Ethylene Oxide Residuals
This test is for devices sterilised using ethylene oxide and identifies the level of residual ethylene oxide using a liquid extraction followed by analysis with a Gas Chromatograph.