Using Hydrogen Peroxide for Terminal Sterilization—A Medtech Makers Q&A

By Sean Fenske, Editor-in-Chief

Recent concerns regarding the environmental and health impact of ethylene oxide (EtO) for the terminal sterilization of medical devices has manufacturers seeking alternatives. While there are a variety of different methods that can be used, each comes with its own set of pros and cons. Not all processes are compatible with all types of medical devices and only certain types can be used for specific technologies.

Fortunately, one solution that can be used broadly across many medical devices and has virtually no environmental concerns is garnering significant attention. Hydrogen peroxide (H₂O₂) sterilization provides an array of benefits to the industry. The U.S. FDA has even indicated its endorsement of vaporized hydrogen peroxide as a viable alternative for device sterilization.

Given the interest in sterilization alternatives, two representatives from De Lama have participated in the following Q&A to offer further insights on the use of H₂O₂. Guido Rovera, sales and marketing director, and Marco Bianchi, marketing and communications manager, provide clarification on this option for medical device manufacturers and why it may be a good fit for many companies.

Sean Fenske: What’s driving medtech organizations to explore alternative or non-traditional methods for sterilizing medical devices?

Marco Bianchi: The main driver for medtech companies is to eliminate EtO (ethylene oxide) sterilization, which is a polluting, toxic, and dangerous to handle process. Transitioning to a greener method is of great interest to companies, but it is also being pushed by the FDA and EPA. It’s important to note in January 2024, the FDA added vaporized H₂O₂ to Class A sterilization methods, giving a significant boost to the use of this media as a sterilizing agent.

In addition, many companies are seeking to internalize the sterilization method to speed up the process and maintain more control of overall production. While it is challenging to internalize ethylene oxide, gamma/beta rays, or E-beam sterilization, it is substantially simpler with HyPerPure® Hydrogen Peroxide Sterilization, which only needs connections to electricity and compressed air.

Fenske: What is HyPerPure® with vapor phase hydrogen peroxide and how does it differ from vaporized hydrogen peroxide (H₂O₂) or plasma H₂O₂?

Guido Rovera: HyPerPure® is a cold sterilization technology with vapor phase H₂O₂. Our temperature cycle spans from 25°C to 40°C (77°F to 104°F), which copes perfectly with thermo-sensitive medical devices. HyPerPure® has been a game changer because it works in deep vacuum (up to 1 mbar). We have been able to reproduce the concept of steam sterilization, which works with a saturated steam atmosphere, creating the concept of an atmosphere saturated with H₂O₂ vapors.

Further, this process is facilitated with a patented De Lama H₂O₂ generator—HyPerGeneSys®—which is able to work under vacuum and ionize H₂O₂ molecules, enhancing the “lethality” effect and making the process faster and more effective.

Now, let’s review the differences with plasma H₂O₂. Plasma H₂O₂ can’t be used in chambers bigger than 160 liters (42.27 gallons), which is not ideal for industrial scale production. De Lama’s HyPerPure® can be used with chambers from 150 liters up to 90 cubic meters (from 39.63 gallons up to 23,776 gallons), built in custom sizes and shapes. For this reason, it can be delivered with chambers as big as those used for mass sterilization EtO.

Also, the HyPerPure® process permits customization through several parameters (e.g., vacuum level, temperature, number of pulses, etc.) in order to perfectly suit the customer’s product to be treated.

Fenske: Given the safety concerns regarding ethylene oxide, can you speak to the safety of HyPerPure®?

Bianchi: HyPerPure® is completely safe. Since H₂O₂ is being used, at the end of the cycle, after passage through a catalytic filter, the gas is expelled into the environment as molecules of water and oxygen. There couldn’t be anything more green. According to the regulations (i.e., ISO 22441:2022), opening the door at the end of the cycle can be performed when the H₂O₂ concentration is 1 ppm or less. Also, since a pressure vessel is not used, there is no risk of an explosion; no ATEX authorizations are required, unlike EtO chambers.

Fenske: With sustainability growing in importance for medical device manufacturers, can you provide further insight on the green aspects of HyPerPure® you mentioned?

Rovera: We can confidently state HyPerPure® is the greenest sterilization method in the world. First, as Marco already said, there is no toxic emission released into the environment. Also, when compared to traditional saturated steam sterilizers, HyPerPure® saves, on average, 70% of energy, 70% of CO₂ emissions, and 100% of water, which is remarkable. All these savings can, at the same time, avoid a waste of resources and save money for the user.

Fenske: What types of products are ideally suited to be sterilized with HyPerPure® and what types of products would not be a good fit?

Bianchi: HyPerPure® is able to sterilize all types of products except liquids. Many incompatibilities present in the literature with H₂O₂ that don’t apply to HyPerPure® since our method doesn’t create any condensation. The H₂O₂ never converts to a liquid status in contact with the product. Additionally, since only a single sterilization process is required, there is never a need for multiple sterilizations.

There is only one potential challenge with this process. HyPerPure® doesn’t work well with a double wall cardboard box, because the box will act like a sponge and possibly cause a problem in achieving an adequate delivery of H₂O₂ to the target. This can be avoided by transferring the product to the final packaging after the sterilization cycle or by using plastic recyclable perforated plastic boxes, which are often already in use with EtO sterilization.

Fenske: What other benefits are realized from sterilizing medical devices with HyPerPure® that we haven’t discussed?

Rovera: Besides the green aspects and the ability to bring the technology in-house as we already covered, the most significant benefits include the time to perform the process as well as cost savings—both in CapEx and OpEx—and space savings.

With regard to the time the process takes, the average cycle on HyPerPure® spans from three to five hours, dramatically lower than EtO’s 48 to 72 hours for processing. Part of this saving comes from HyPerPure® not requiring any pre- or post-conditioning phases.

The CapEx savings are realized in the overall cost of the HyPerPure® equipment. This expense is lower than a complete EtO plant as all the ancillary devices, such as burners and pre-/post-conditioning chambers, are not necessary. In addition, by eliminating these ancillary devices, a space savings of approximately 70% is achieved—significant for a production plant.

Further, the OpEx is very low. HyPerPure® uses commercial H2O2 tanks, which are available on the market. Customers are not captive to De Lama for cartridges or expensive branded H2O2 tanks. And, as mentioned previously, the energy consumption is quite low, water use is zero, and there are no consumables. The static filter is metal coated and engineered to last at least 10 years.

Fenske: Do you have any additional comments you’d like to share based on any of the topics we discussed or something you’d like to tell medical device manufacturers?

Bianchi: I’d like to highlight that HyPerPure® has been improved year after year and, with nine years on the market, should be considered a mature and proven technology. The De Lama team is always available to run a set of free trials for customers to prove the effectiveness of the sterilization and ensure material compatibility. Most of the major players in medical device manufacturing have already purchased our technology and are shifting their production to HyPerPure® for a greener, more efficient production. I’d also like to add that we are proud to mention the pharma market is embracing this technology, as well, as an alternative to saturated steam to dramatically reduce CO₂ emissions and save water and energy.

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