title: Sterility test method for petrolatum-based ophthalmic ointments.
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.
mesh_terms: D001412:Bacillus subtilis / Q000302:isolation & purification; D001419:Bacteria / Q000187:drug effects / Q000302:isolation & purification*; D001431:Bacteriological Techniques / Q000592:standards; D004926:Escherichia coli / Q000302:isolation & purification; D005227:Fatty Acids / Q000494:pharmacology; D005374:Filtration; D008722:Methods; D009824:Ointments / Q000592:standards*; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D012475:Salmonella / Q000302:isolation & purification; D012997:Solvents; D013210:Staphylococcus / Q000302:isolation & purification; D013501:Surface-Active Agents
chemical_list: D005227:Fatty Acids; D009824:Ointments; D012997:Solvents; D013501:Surface-Active Agents