Mucoadhesive Properties of a New Intimate Hygiene Cleanser againstVulvovaginal Candidiasis

Abstract

Objective: Performance of feminine cleansers can be improved by increasing antimicrobial potency and favouring the prolonged contact on vulvo-vaginal mucosa of active ingredients, that permits the increase of the persistence of their activity, and consequently of their efficacy. The presence of specific polymers in topical formulations allows the cleansing solution to adhere to mucosal substrates. The associations of xanthan gum with lambda carrageenan from Chondrus crispus has a high mucoadhesive potential. The aim of our study was to evaluate the mucoadhesive potential and the safety of an innovative cleanser for feminine hygiene (SA3) compared with a reference cleanser (SA) in a double-blind design. Material and Methods: The cleansers were provided at dilutions: the reference product containing thymol from Thymus vulgaris extract at pH 3.5 (SA), and the test one with Zinc Coco Sulfate for its antimicrobial action, and Xanthan gum and Chondrus crispus extract as mucoadhesive agents (SA3) added to SA. The pro-sensitizing test was performed on cultures of human monocytes THP-1. The expression of two membrane markers, CD86 and CD54, was evaluated and compared with the sensitizing 2,4-dinit rochlorobenzene as a positive control, and with untreated cells as a negative control. Light scattering images were used to analyze the morphology of THP-1 cells. The mucoadhesivity was assessed as percentage of inhibition of the lectin-binding glycoprotein. Results: No changes in CD86 and CD54 expression were evidenced in the cells exposed to the test product, compared to the untreated cells. Furthermore, no significant alteration of the cell morphology was observed for SA3. Mucoadhesion% values showed a statistically significant difference in favor of SA3 even at 1:2 and 1:5 dilutions. At the higher dilution, SA3 lost only 23.2% of mucoadhesion versus the lower one, compared to the 45% lost between the two SA dilutions. Conclusion: No pro-sensitizing potential and no significant alteration of the cell morphology were observed for SA3 compared to the untreated cells. SA3 is safe, with high mucoadhesion to the vulvo-vaginal mucosa, significant even at higher dilution.