Key Points
- The following are four common types of medical device sterilization methods that medical device manufacturers use today:
- Ethylene oxide is a colorless gas in a low temperature process widely used to sterilize a variety of medical devices.
- Gamma irradiation uses Cobalt 60 to kill microorganisms by breaking down its DNA.
- E-beam irradiation uses high-energy electrons for a variety of applications to include sterilization of medical devices where it inactivates microorganisms by destroying their vital molecules.
- Steam sterilization works by exposing the medical device to saturated steam under pressure.
The Most Common Medical Device Sterilization Methods
The EO Sterilization Method
Ethylene oxide (EO) is a colorless gas used to sterilize a variety of medical devices. The EO sterilization method uses a three-part process to sterilize devices efficiently:
- Preconditioning: The first step is to prepare the product for sterilization, which is performed in a room or cell designed to distribute heat and relative humidity across the medical devices to stabilize these conditions before moving on to the chamber process.
- Chamber: During the chamber cycle, the product is exposed to a series of controlled phases where the desired temperature is maintained. The phases expose the products to relative humidity and EO gas for a predetermined amount of time. Safe cycles are designed to use nitrogen before, during, and after EO gas phases.
- Aeration: After the chamber cycle is completed the products are placed in controlled heated cells or rooms for a determined period of time where any EO residuals remaining on the product continues to dissipate.
Device Types
According to the FDA, about 50% of all medical devices in the U.S. are sterilized using the EO sterilization method. The device types sterilized using EO range from assembled complex devices, custom procedure kits, wound care dressings, to stents.
Benefits of Using EO Sterilization
There are a variety of benefits associated with using EO sterilization. It allows medical devices to be sterilized in their final packaging since the gas permeates sealed packages and cartons. Large volumes of products can be sterilized together within the chamber.. EO is compatible with many materials. It is non-corrosive to plastics, metals, and rubber materials.
EO sterilization processing has become more efficient and competitive with Gamma irradiation or E-Beam with its turn-around time with cycles that are validated using Parametric Release. This allows for the products to be released after reviewing the EO sterilization processing data instead of waiting for microbial testing.
The Gamma Irradiation Sterilization Method
Another common way to sterilize medical devices is by Gamma irradiation. Gamma irradiation uses Cobalt-60 by killing bacteria and other microorganisms by breaking down its DNA. The Gamma irradiation sterilization method takes the products while in their sealed packages and cartons and places them in specific totes or pallets where they pass through a specifically designed cell on a conveyor where the products are exposed to high energy gamma rays produced from the radioactive decay of the Cobalt-60.
Device Types
Gamma irradiation sterilization is used for a variety of device types including:
- Plastic syringes
- Hypodermic needles
- Scalpels
- Surgical blades
- Adhesive dressings
Benefits of Using Gamma Irradiation Sterilization
Using the gamma irradiation sterilization method offers a wide range of benefits. Gamma rays have a high penetration power, so materials can be sterilized after being placed in its final packaging. Another advantage of using this sterilization method is that it is reliable and accurately controlled. Gamma irradiation effectively sterilizes a wide range of products with different variations in dose requirements, densities, and packaging.
Validations of Gamma irradiation or E-Beam are less complex than EO sterilization, but require very specific monitoring on a quarterly basis.
The E-Beam Sterilization Method
Along with Gamma and EO sterilization, E-beam is another method that can be used to sterilize medical devices in their final packaging. E-beam sterilization inactivates microorganisms by destroying their vital molecules or using an indirect chemical reaction. E-beam sterilization works by accelerating a beam of electrons to near light speed, passing through a scanning chamber into a curtain of electrons. The medical devices move through the chamber on a conveyor where it’s showered with high-energy electrons that penetrate the device.
Device Types
E-beam sterilization is a cost-effective, safe way to sterilize a variety of medical devices like:
- Drug containers
- Syringes
- Test tubes
- Catheters
- Labware
- Pipette tips
Benefits of Using E-Beam Sterilization
One benefit of E-beam sterilization is that it offers a fast turnaround time, similar to Gamma irradiation as compared to EO sterilization. The E-beam method also has a faster dose rate and less material degradation compared to the Gamma irradiation sterilization method.
The Steam Sterilization Method
Another common sterilization method is steam sterilization. The process works by exposing the medical device to saturated steam under pressure. The steam kills microorganisms by reducing the time and temperature needed for the proteins to survive. It is crucial to ensure that the medical device’s steam sterilizer chamber reaches and stays at a certain temperature for the recommended amount of time. Recommended temperatures for steam sterilization are 250° F (121° C), 270° F (132° C), and 275° F (135° C).
Device Types
Steam sterilization is used for a variety of device types like surgical instruments, biopsy forceps, and implanted medical devices.
Benefits of Using Steam Sterilization
Steam sterilization is a non-toxic and low-cost sterilization method. Steam sterilization equipment is fast and capable of seamlessly processing heat and moisture stable materials compared to other sterilization methods.
Providing You With Medical Device Sterilization Methods
At Remington Medical, we offer solutions for each of the most common medical device sterilization methods that result in sterile, high-quality medical devices. From EO sterilization to steam, we’re experienced and equipped to handle every type of sterilization method. We know best practices for the different types, ensuring that you get the best method based on your product needs. Contact us today to learn more about which medical device sterilization method is right for your product.
