Self-preserving personal care products.

Objective: As questions on the safety of some popular preservatives are on the rise, there is a growing interest in developing 'self-preserving' personal care products. Use of multifunctional ingredients/actives with antimicrobial properties has been explored as replacements for conventional preservatives. This study explores the use of combinations of multifunctional actives (MFA) and other cosmetic ingredients in various personal care formulations, to deliver microbiologically safe self-preserving products. Products studied in this study include face wash, gel-based leave-on skin care product and face mask.

Methods: Minimum inhibitory concentration (MIC) of several cosmetic ingredients was determined to identify multifunctional actives with antimicrobial activity. Personal care formulations made with multifunctional actives and other cosmetic ingredients were studied for preservative efficacy by challenging the product with six multiple cycles of microbial challenge.

Results: Formulations with combinations of multifunctional actives with antioxidant (AO) and chelators (CHL) were found to work synergistically and were highly efficacious in controlling multiple microbial challenges as observed in the preservative efficacy test (PET) studies. The effective combinations were able to withstand up to six multiple microbial challenges without product degradation. The preservative efficacy profile was similar to control formula containing preservatives.

Conclusion: Self-preserving personal care/cosmetic products can be developed which are as efficacious as preserved products by a prudent selection of multifunctional actives, antioxidants and chelators as a part of the formulation.