USP - 51 - Nelson Labs - Bozeman

All pages for the Nelson Labs Bozeman testing services can now be found on our parent company’s website:

1765 South 19th Ave Bozeman, MT    

USP - 51

USP - 51


The U.S. Pharmacopeia describes in General Chapter 51, the assay they recommend for testing preservative efficacy. The USP divides products into four categories:

Category 1 - Injectable, emulsion, otic, sterile nasal and ophthalmic products made in aqueous bases

Category 2 – Topically used products made with aqueous bases or vehicles; nonsterile nasal products and emulsions, including those applied to the mucous membranes

Category 3 – Oral products other than antacids, made with aqueous bases or vehicles

Category 4 – Antacids made with an aqueous base

Each category of products is challenged with five microorganisms independently and samples are taken at intervals specified for each category throughout 28 days.



In-Vitro Testing Laboratory

Scientists in our In-Vitro testing labs are well trained on ASTM, AATCC, AOAC, CLSI and EN standard methods. The efficacy testing services of this laboratory include MIC/MBC, ...

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