USP Antibiotic Testing

Bacteriostasis and Fungistasis (B&F)
MDS offers USP antibiotic testing services to evaluate the potency of an antibiotic against USP standards in whether a pharmaceutical substance or medical device exhibits antibacterial activity.

Each sterility test should be qualified by a bacteriostasis and fungistasis (B&F) test. The B&F test demonstrates that the test article itself is not inhibitory to the growth of microbial contaminants that can be present in the test sample. This assay must reflect the actual sterility test methodology that will be used on the sample. If bacteriostasis or fungistasis is observed during the conduct of the B&F test, adjustments to the testing methodology are made to eliminate, if possible, the cause of the stasis

Qualitative Testing
The zone of inhibition is a qualitative test. Samples usually 100 g or 100 mL each are submitted in sterile containers. Our microbiologists cultivate these samples in a nutrient (agar) medium. Any zones wherein bacterial growth is inhibited are measured, and compared to controls.

Quantitative Testing
MDS also conducts quantitative testing to measure microgram quantities of antibiotics in biological products, drug products, or animal tissue using the cylinder plate method. Endotoxin tests also help quantify the amount of antibiotic in the sample.