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 opthalmic 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 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, biofilm prevention and removal, time-kill kinetics, clean room disinfectant validation, zone of inhibition and custom efficacy studies for disinfectants, antimicrobials and other products requiring EPA registrations and FDA 510(k) submissions. Studies in…

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