What Is Bioburden Testing?

Bioburden testing is an assessment of the microbial contamination level on a device in order to ensure it meets regulatory standards and is safe for use. This is done before the device undergoes any type of sterilization process and is necessary — no regulatory submissions can be completed without it.

EN ISO 11737-1 is a standard that specifically addresses the determination of the population of viable microorganisms on or in a medical device, component, raw material or package — making bioburden testing essential for manufacturers looking to comply. 

How is bioburden testing performed?

The goal of bioburden testing is to quantify and identify microorganisms to ensure products meet specified quality standards and regulations. Here is a brief overview of how it’s performed:

1. Sample Collection. Representative samples are collected aseptically from the medical device.
2. Sample Preparation. Microorganisms are extracted from samples and diluted appropriately for counting.
3. Microbial Enumeration. Viable microorganisms are quantified using either plate count or membrane filtration methodology. The plate count method involves spreading diluted samples on agar plates, incubating them and counting visible colonies for bioburden determination. The membrane filtration method filters samples through a membrane before counting and determination.
4. Microorganism Identification. Microorganisms are identified as needed at this point in the process.
5. Analysis and Reporting. Results are analyzed and a comprehensive report is compiled that includes bioburden levels and identified microorganisms.
6. Validation and Calibration. Testing methods are validated for accuracy and precision.

Meeting the Requirements of EN ISO 11737-1, ISO 11737-2, and ISO 11137-2.?

The full title of this standard is “EN ISO 11737-1:2018 – Sterilization of health care products – Microbiological methods – Part 1: Determination of a population of microorganisms on products.” 

It is part of a series of standards related to the sterilization of healthcare products that includes ISO 11737-2, ISO 11737-3 and ISO 11737-4. 

A CRO partner like NAMSA makes meeting these standards a lot easier by providing guidance and support in relation to:

• Compliance. Our team includes experts in microbiology, quality assurance and regulatory compliance — they know their standards well, including EN ISO 11737-1, ISO 11737-2, and ISO 11137-2. 
• Testing. We’re fully capable of conducting the necessary tests according to the requirements specified in the standards. This includes bioburden testing but also extends to testing for sterility and other microbiological parameters.
• Validation. ISO 11137-2 specifically relates to sterilization of health care products – Radiation. We can perform validation studies — dose verification, bioburden determination and related — for radiation sterilization processes to help ensure criteria-meeting effectiveness. 
• Documentation. We provide comprehensive and compliant documentation that helps streamline the regulatory submission process. Not only that — we stay on top of changes and updates to standards to help you stay proactively well-documented.

Need to talk to someone about your bioburden testing needs? Contact a NAMSA representative.