Sterility Testing and Microbial Limit Tests
Start with the big picture
Sterility testing checks for viable microorganisms in products intended to be sterile, while microbial limit tests (MLTs) assess microbial counts and specified microorganisms in non-sterile products. Sterility testing may use direct inoculation or membrane filtration; the source describes incubation in two media types at two temperatures for 14 days. Bacteriostasis and fungistasis testing checks that a product does not inhibit microbial growth in the test media. MLTs include total aerobic microbial count, total combined yeast and mold count, and tests for specified microorganisms. Acceptance criteria vary by product route, including oral, topical, nasal, rectal, and vaginal products. Validated methods, GMP-compliant environments, routine monitoring, and environmental controls support reliable testing and contamination prevention.
What you'll learn
- Distinguish sterility testing from microbial limit testing.
- Identify direct inoculation and membrane filtration as sterility-testing methods.
- Describe the purpose of bacteriostasis and fungistasis testing.
- Identify the main components of microbial limit tests.
- Explain how validation and environmental controls support microbial quality.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
