Sterilisation and disinfection
Information on suitable tissue sterilisation methods
Surgeons will be familiar with many sterilisation techniques used to decontaminate surgical instruments, medical devices, etc. Some of these (eg high temperature sterilisation) are not suitable for tissues. Research scientists within Tissue and Eye Services have carried out comprehensive evaluations of sterilisation techniques to determine which are suitable for which tissues. The tissues have subsequently been validated to ensure that essential biological and biomechanical properties have not been adversely affected, and that the graft remains biocompatible.
Various model systems using bacterial spores and viruses have been used to simulate worst-case scenarios. In addition, the sterilisation procedure complies with European Standards ISO 11137 and it is titled Sterilisation of healthcare products where appropriate.
For viable (living grafts), banked using cryopreservation techniques, the application of a 'sterilisation' method would not be appropriate as this would also kill the tissue cells. In these cases we have developed disinfection methods that kill bacteria without compromising donor cell viability. Where appropriate, validation studies have been published in peer reviewed journals (see references below).
We believe that the use of validated decontamination procedures minimises the risk of disease transmission and enhances the safety of tissue allografts.