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Sterility test method for petrolatum-based ophthalmic ointments.

K Tsuji·E M Stapert·J H Robertson·P M Waiyaki
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Abstract

A sensitive sterility testing procedure for the detection of microbial contamination in petrolatum-based ointments is described. The method involves dissolving the ointment in filter-sterilized isopropyl myristate and filtering through a membrane filter. Improved sensitivity is obtained by blending the membrane in Trypticase Soy Broth before incubation. Filter-sterilized isopropyl myristate is shown to be less toxic to microorganisms than heat-sterilized isopropyl myristate. The isopropyl myristate method is more sensitive than the polyethylene glycol-ether method for the detection of microbial contamination.

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Bacillus subtilisBacteriaBacteriological TechniquesEscherichia coliFatty AcidsFiltrationMethodsOintmentsPseudomonas aeruginosaSalmonellaSolventsStaphylococcusSurface-Active AgentsJournal Article

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BibTeXRIS

K Tsuji, E M Stapert, J H Robertson, P M Waiyaki. 1970. Sterility test method for petrolatum-based ophthalmic ointments.. https://doi.org/10.1128/am.20.5.798-801.1970

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