Sterility Testing

Sterility Testing is a critical quality control procedure employed in the pharmaceutical industry to assess the absence of viable microorganisms in pharmaceutical products that are intended for injection or implantation [1]. A common methodology of measuring this is USP <71>. The test aims to ensure the sterility of the product.

History of Sterility Testing

The history of sterility testing can be traced back to the late 19th century when the pharmaceutical industry recognized the importance of ensuring that injectable and implantable products were free from harmful microorganisms. Sterility testing methodologies have evolved over time, becoming more sophisticated and standardized since this point, and measures have become much stricter in the commercialization of these methodologies. The United States Pharmacopeia (USP) has played a pivotal role in developing and updating guidelines for sterility testing to meet modern regulatory and safety requirements.

Importance of Sterility Testing

USP <71> Sterility Testing ensures that pharmaceutical products are free from microorganisms that could cause infections when administered [1]. Prior to its implementation, the pharmaceutical industry had experienced several instances where microbial contamination has affected final product and consumers, including the largest case occurring at the New England Compounding Center (NECC), where over 750 patients in 20 states were diagnosed with a rare form of meningitis after they were given contaminated injections. More than 100 patients died as a result [2]. Ensuring sterile operations, even for products relating solely to further manufacturing or research use is now more important than ever following such an impactful case.

How is USP <71> assessed?

USP <71> Sterility Testing typically involves taking a sample of the pharmaceutical product in an aseptic manner. This sample is then transferred into growth media that promotes the growth of aerobic and anaerobic microorganisms. The media-containing sample is then incubated under specific conditions for a specified duration. After incubation, the media is observed for the presence of microbial growth. If no growth occurs, the product is considered sterile. If microbial growth is detected, it indicates a failure of sterility, and further investigation is required [1]. Sterility testing in buffers, reagents, and media is beneficial in preventing contamination in final experimental products, protecting the individuals handing them, and ensuring reproducibility.

Considerations and Limitations of USP <71>

Aseptic Techniques Aseptic techniques must be strictly followed during the sampling and testing process to avoid introducing contaminants.
Time Efficiency Sterility testing is time-sensitive, and the duration of incubation must be carefully controlled to yield accurate results.
Analysis of Results False positives and negatives can occur due to various factors, so results should be carefully interpreted and confirmed.
Equipment Maintenance Special attention should be given to the sterility of testing equipment, such as filtration systems and culture vessels, to prevent contamination during testing.

In addition to Sterility Testing, Boston BioProducts provides a comprehensive set of QC tests for custom reagents. Learn more about custom reagent development services.