Applicable Standards
- EP
- USP
- ISO
- AAMI
- ASTM
Services Summary
Nelson Labs is a leading provider of sterility assurance test services for medical device, pharmaceutical and tissue manufacturers for both sterile and nonsterile products. Most tests follow United States or European Pharmacopeia (USP or EP) and similar international standard sterilized medical device standards are also found in ISO, AAMI and ASTM guidance documents.
Bioburden
Bioburden tests determine the total number of viable microorganisms in or on a medical device, container or component. It is performed on any product that requires control and/or monitoring of bioburden counts, usually as part of a sterilization program. This test acts as an early warning system for possible production problems that could lead to inadequate sterilization. It is also used to calculate the necessary dose for effective radiation sterilization and to monitor product routinely as part of quarterly dose audits.
For clarification, product bioburden is intended for medical devices, containers and components. However, we also offer standard plate counts and microbial enumeration studies for powders, solutions and similar products where reconstitution and filtering may be required. Tissue products may also be assessed for bioburden.
Product Sterility: Rapid & Traditional
Product sterility testing plays a vital role in safeguarding product safety through the detection of microbial contamination. Nelson Labs provides testing capabilities across traditional cleanrooms, isolators, and a new state-of-the-art, EU GMP Annex 1-aligned cleanroom in Salt Lake City, Utah. With deep technical expertise and a range of testing environments, Nelson Labs helps customers identify the optimal sterility testing methodology for their unique needs.
Traditional compendial sterility testing includes a 14-day incubation period following testing to allow potential microbial contaminants to grow to detectable levels. For many products, rapid sterility testing using validated rapid microbiological methods (RMMs) can substantially shorten this timeline, delivering results in as little as 6 days.
All sterility test methods require validation through method suitability testing (bacteriostasis/fungistasis testing) to demonstrate that the product does not interfere with microorganism recovery. For isolator-based testing, peroxide ingress verification is also conducted to ensure the isolator decontamination process does not impact test performance.
BI Sterility: Rapid & Traditional
Biological indicators (BIs) are commonly used to monitor and verify the effectiveness of sterilization processes. They provide direct evidence that a sterilization cycle can effectively inactivate highly resistant microorganisms. Following a sterilization cycle, BIs are typically incubated in a growth medium for 7 days at the appropriate temperature for the test microorganism, allowing any surviving organisms to proliferate and be detected.
In addition to conventional BI testing, Nelson Labs offers patent-pending RapidCert™ BI testing, which reduces the incubation time to 48 hours. RapidCert™ can help customers accelerate product release, streamline sterilization validation activities, gain earlier insight into process performance, and significantly reduce turnaround times.
BIs are widely used across a variety of sterilization modalities, including ethylene oxide (EO), steam, dry heat, vaporized hydrogen peroxide (VHP), ozone, and other emerging sterilization technologies.
In many applications, BIs are incorporated into process challenge devices (PCDs), which are designed to simulate worst-case sterilization conditions. By creating a greater challenge to the sterilization process, PCDs help demonstrate that the cycle can consistently achieve the required level of microbial inactivation.
Bacterial Endotoxins
Nelson Labs provides a bacterial endotoxins test (BET), which is an in vitro assay for detection and quantitation of bacterial endotoxins, a component of the cell wall of Gram-negative bacteria. While a traditional BET relies on limulus amebocyte lysate (LAL), a reagent derived from horseshoe crab blood, Nelson Labs also offers a recombinant BET using recombinant cascade reagents (rCR), which are not derived from animals. The BET (through traditional and recombinant methods) is performed as part of the lot release testing for medical devices with direct or indirect contact to the cardiovascular system, lymphatic system, or cerebrospinal fluid. Injectable pharmaceutical products must also be tested for bacterial endotoxins. Routine monitoring of water systems and incoming materials can help to ensure that the process does not contribute endotoxins to the final product.
Particulate Analysis
Particulate Analysis testing includes procedures for removing, counting and sizing particulate contaminants on or in medical devices, stents, catheters, pharmaceuticals, IV bags and contact lens solutions. This test is useful for determining the amount of particulate matter coming from the manufacturing environment and use of the medical device or pharmaceutical product as well as identifying the potential sources of particulates. Nelson Laboratories performs both USP recommended methods: Light Obscuration (via the HIAC ROYCO particle counter) and traditional Microscopic methods.
Sterilant Residuals
Sterilization processes may leave sterilant residuals on product after the sterilization process. For processes such as Ethylene Oxide (EO), the assessment of sterilant residuals, aeration time and safe levels are required. Nelson Labs provides sterilant residual testing for EO, H202 and other common sterilization process residuals.
Microbial Identifications
Microbial or Organism Identification tests are used to characterize product bioburden and/or environmental bioburden and to identify organisms in sterility positives. For tissue products, a confirmation of the presence or absence of possible objectionable organisms can also be performed. Nelson Labs employs genotypic identifications using the MicroSeq system along with traditional Gram stain and other lab techniques.
Pharmaceutical Routine Test Services
Specific to pharmaceutical manufacturers, Nelson Labs provides routine USP and EP compendial tests for product sterility (isolator), bacterial endotoxin, particulate analysis, antibiotic potency assays (APA), antimicrobial preservative efficacy studies (APE) and microbial identification services. For nonsterile pharmaceutical products such as transdermal patches, we also offer routine microbial enumeration studies for objectionable organisms (USP 61/62).
Tissue Routine Test Services
Specific to tissue processing and preservation, Nelson Labs provides routine USP and EP compendial tests for microbial enumeration studies to assess objectionable organisms and standard bioburden tissue tests for general bioburden load assessments. Microbial identifications can also be performed to characterize the bioburden load and type. Unique issues arise with tissue products, specifically inhibition due to the use of antibiotics for preservation of tissue material, which must be validated with a suitability study prior to performing some routine tests.
If you have additional questions about Sterility Assurance test services, or would like to consult with the experts at Nelson Labs, just send us a request or call us at +1 (801) 290-7500.
