Sterilization of medical devices plays an important role in the product development although it is not heavily invovled or nealy not involved in academic research in universities. It need to be considered in the earlier stage of prototype development, which can avoid the complex or even failure in the later stage.
Sterilization is defined as a “validated process used to render product free from viable microorganisms.” Terminal sterilization is defined as the “process whereby product is sterilized within its sterile barrier system.” The terminal sterilization process is considered a manufacturing process step itself and usually takes place at, or near, the end of the manufacturing process.
The presence of microorganisms is expressed as a probability. While the probability can be reduced to a very low number, it can never with certainty be reduced to zero. This is why we use the term Sterility Assurance Level (SAL) to express a sterile claim. SAL is the probability of a viable microorganism being present on a product after sterilization. Normally expressed as 10-n. 10-3 or a 10-6 value being used most frequently for sterilization. Common SAL for medical devices is 10-6.
Sterilization is accomplished principally by radiation, chemical sterilants, steam under pressure, dry heat, and filtration or combinations thereof. General application and method of sterilization can be learned in
Wiki. A more detailed Guideline for Disinfection and Sterilization in Healthcare Facilities
can be found in Centers for Disease Control and Prevention (CDC)
It is important to distinguish sterilization from disinfection, which does not ensure the same security level and does not necessarily inactivate all forms of microorgan- isms – bacterial spores, for instance.
A sterile medical device is one that is free of viable microorganisms. For a sterile medical device this can be achieved through:
- A terminal sterilization process
- Sterilization of components, followed by sterile filtration and aseptic filling into a sterilized container
- A combination of chemical/physical sterilization and aseptic processing
The choice of the sterilization method for medical devices depends on a number of factors including the type of material used in medical devices, the type of packaging materials (product packaging and final packaging), the number and type of microorganisms involved, and the classification of the item.
