Example 17

Contaminating micro-organisms in cosmetics may cause a spoilage of the product and, when pathogenic, they represent a serious health risk for consumers worldwide. The United States Pharmacopoeia (USP) Microbial Limits Test provides several methods for the determination of total microbial count for bacteria, yeast and mold. Various gels of the present disclosure were tested to evaluate the possible microbial contamination in three different states of their use (intact, in-use, ending product). FIG. 96 is a table summarizing the results of such testing.

The samples of gel and water samples from carboys were analyzed for determination of CFU/mL (colony forming units per milliliter) of aerobic bacteria as well as yeast and mold. Samples were exposed to growth medium of Tryptic Soy Agar (TSA) for bacteria and Potato Dextrose Agar (PDA) for fungi (yeast/mold) at an exposure temperature of 23±3° C. Samples were incubated at 30.0±2° C. for 3 days (bacteria) and 5 days (Fungi). Samples were then observed for determination of colony-forming units/mL.

The limit of detection for the assays was 10 CFU/ml or g for bacteria and fungi, and the values of <10 indicate that microorganisms could not be detected in the samples. Values of >1.00E+04 indicate that the microbial colonies are Too Numerous to Count in the dilutions plated.

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