Discovering the business and management of sterilization
Sterilization: a key expertise ensuring safety and quality at Mora Group
Sterilization is a key stage in the manufacture of devices for the medical and pharmaceutical sectors. To understand the challenges involved, Vincent Collard shares his experience of this demanding process, which has become a real confidence-building factor for our customers.
Hello Vincent, could you describe your career path for us?
I’m Vincent Collard, Technical Director of the MORA Group and a mechanical engineer with a degree from UTC Compiègne. I began my career in subcontracting before spending 15 years in the automotive industry, where I developed sensors for engines and mechatronic systems for customers such as PSA, Renault, BMW and Ford. I managed development teams and supervised the entire project lifecycle, from design to production. I then decided to take on new challenges by becoming a key account project manager in the solar power plant sector, working with EDF and Aéroports de Paris on large-scale projects. Today, I put this experience in managing complex projects to work for MORA, supporting our customers with rigor and expertise.
Today, I put this experience in managing complex projects to work for MORA, supporting our customers with rigor and expertise.
Can you explain sterilization at Mora Group?
Mora Group has been involved in product sterilization for almost ten years. This process mainly concerns products manufactured in cleanrooms and intended for the medical sector. We had noticed that some of our long-standing customers were sterilizing their parts themselves as soon as they received them.
As a rule, sterilization takes place at the final stage of the process. Once the products have been injected and packaged, they undergo sterilization before being sent to the end customer.
Mora Group’s commitment to sterilization management processes was prompted by the needs of a long-standing customer developing a pre-filled, single-use auto-injector.
This is a needle-free medical injection device, with MORA injecting the plastic components. As the drug comes into direct contact with the thermoplastic parts before being administered to the body, this is a particularly critical product. It is therefore essential to sterilize the injection nozzle assembled with its cover, a part manufactured by MORA, in order to eliminate any risk of infection for the patient in the event of contamination of the drug.
To guarantee optimum mastery of this requirement, we have called in specialists to deepen our knowledge and develop our skills, as well as our sterilization processes. However, this sterilization stage is not carried out in-house: we rely on subcontractors who are experts in this field.
In concrete terms, we deliver the packaged products to a service provider who takes care of sterilization. Once sterilization has been completed, the products are shipped directly to the end customer.
Can you explain what sterilization actually means?
The sterilizer can use a variety of methods, including radiation sterilization (X or Gamma), heat sterilization (dry or wet), and ethylene oxide (EtO) gas sterilization.
To date, we have outsourced gamma radiation sterilization, a technique widely used in the medical and pharmaceutical sectors. Its main aim is to eliminate any form of contamination present on the product (micro-organisms). These include bioburden and endotoxins, which are contaminants requiring strict elimination.
Gamma rays are used to neutralize these elements at doses of between 25 and 50 kGy, guaranteeing a level of sterility in line with regulatory requirements and industry standards.
Can you tell us more about your sterilization methodology and processes?
There are 4 main stages in the sterilization process.
The first step is to validate the sterilization method, a key phase in the development and pre-project phases. This validation confirms the effectiveness of the chosen technique. In our case, we use the VD max 25 method, which requires rigorous evaluation. It is based on determining the population of micro-organisms present, in compliance with sterilization standards.
To do this, we check the level of bioburden on products according to our manufacturing process. This analysis enables us to determine the sterility dose required to guarantee the eradication of contaminants. This minimum dose must be less than 25 kGy, which represents the minimum sterilization threshold. On the qualified batch, the products are subjected to treatment at the verification dose, followed by rigorous monitoring to ensure that they are perfectly sterile.
There is a direct link between the level of product bioburden and the sterility dose applied. Once the products have been processed, their sterility is checked to verify the effectiveness of the process. This step is the final validation of the sterilization method used.
The sterilization process must also be defined according to the product packaging, whether small containers, cartons or full pallets. In the case of full pallets, these are passed through sterilization tunnels, where they are exposed to gamma radiation treatment, ensuring sterilization of all the products they contain. This stage takes place directly at the sterilizer.
For qualification, we generally have three pallets processed at the same time. These are fitted with radiation dosimeters, positioned on all the cartons. The aim is to ensure that even the carton in the middle of the pallet receives the minimum dose of 25 kGy required for effective sterilization. This step ensures that all products receive a level of irradiation within the set tolerances of 25 to 50 kGy.
This process is known as mapping, and is an essential validation phase in the development process. At the end of this stage, we can guarantee that all products, in their original layout, have received the radiation dose required for sterilization.
It’s important to note that mapping is directly linked to part density and volume, as gamma rays must pass through cartons and products. Once the mapping has been validated, it is specific to the initial sterilization conditions.
Any modification to the product – be it a change of design, material, quantity or even packaging – requires a new cartography. Mapping validation is carried out at a given point in time, and remains valid only as long as the product and packaging parameters remain unchanged.
Sterilization is a particularly critical stage, as it can have a direct impact on patient safety. A flaw in this process could have serious consequences, which calls for absolute rigor and a well-defined methodical framework.
This is why a strict, routine protocol is implemented during series production, with checks carried out every three months. During the pre-production phase, these checks are even more frequent, being carried out for each production batch. This process is logistically demanding and requires precise monitoring: for each production run, representative samples are taken under the same manufacturing conditions, then sent to the laboratory for specific tests.
These tests include LAL (bacterial endotoxin tests) and Bioburden, which are used to check the product’s bioburden and endotoxin levels, and ensure that they remain within thresholds compatible with the defined sterilization ranges. This control protocol is systematically applied to sterilized products.
At Mora, we have also developed in-house product particle control, an essential step in the manufacturing process. This is an in-process control, carried out at each batch to measure the number and size of particles present on the parts produced.
To achieve this, we use a liquid phase particle counting method. The product is immersed in water after being “cleaned”, as it were, of any contaminants. The wash water is then aspirated with a probe, and analyzed by passing in front of an optical cell. This technology, enabled by a special machine, precisely identifies the quantity of particles present in different size ranges from 10 µm to 50 µm and more.
The number of particles detected is then related to a unit of surface area, a measurement expressed in CFU (Colony Forming Units). This analysis enables us to check whether the product complies with the defined cleanliness requirements. In this sense, it helps to qualify the product as clean and suitable for sterilization.
All these steps guarantee a rigorous sterilization process that complies with current standards, ensuring the safety and quality of products delivered to customers.
How are logistics managed at Mora?
As mentioned above, once our parts have been produced, they are sent to the sterilizer. After processing, they are shipped directly to the end customer. However, we manage all the logistics and documentation associated with sterilization.
We are responsible for collecting and transmitting certificates of conformity. These documents include laboratory certificates attesting to the sterilization dose applied, LAL and Bioburden test reports, and the irradiation certificate validating that the pallets have received the minimum required dose in kilograys.
All these documents are then sent to the customer. However, due to the delays involved in issuing the certificates, customers may receive their pallets before these documents have been received. Only after all the sterility and sterilization certificates have been analyzed and validated can the customer officially release the batches for use.
It’s important to distinguish between sterilization and sterility.
- Sterilization is carried out by the sterilizer, who irradiates the products with a dose of between 25 and 50 kGy (in this case). His role is limited to the application of the treatment.
- Sterility, on the other hand, is guaranteed by a series of controls and certificates confirming that the irradiation applied has indeed achieved the required level of sterility.
How do Mora Group customers perceive this know-how?
Many customers and prospects are particularly interested in outsourcing this management, which represents a real differentiating advantage for Mora compared with other plastic injectors. The ability to offer this comprehensive service is an essential added value, particularly for players in the medical and pharmaceutical sectors, who are looking for partners capable of managing these complex requirements.
In addition to integrating sterilization right from the project phase, in particular by validating the method and determining the sterilizing dose, Mora also handles all the logistics involved in this process.
This process goes far beyond conventional plastic injection molding production. It implies rigorous monitoring, an investment in logistical time and quality assurance. This expertise enables Mora to position itself as a trusted partner, capable of meeting the sector’s most stringent requirements.
We have chosen to bring this skill in-house, as it is fully in line with our global approach to managing the cleanliness and pollution of our products. This expertise is essential to guarantee rigorous control and perfect mastery of our internal processes.
To reinforce this approach, we have recruited a quality specialist in this field. Her role is central: she ensures internal controls, supervises interactions with the laboratories carrying out the tests, and ensures that our procedures comply with current standards and requirements. This internal integration enables us to optimize our monitoring, reinforce our responsiveness and ensure exemplary traceability throughout the process.
More and more major customers are looking to delegate the management of sterilization and its follow-up, which reinforces the value of our offer. However, it is essential to remember one crucial point: despite our key role in operational and logistical management, final responsibility for batch release and validation as sterile still lies with the customer.
Our mission is to ensure that the process runs smoothly – from manufacturing, through coordination with laboratories and sterilizers, to product release. We carry out these steps in practice, but the formal, binding act of batch release remains the responsibility of the end customer.