The effect of additives on release and in vitro skin retention of flavonoids from emulsion and gel semisolid formulations

• Published in: International journal of cosmetic science 2017-08, Vol.39 (4), p.442-449
• Main Authors: Dyja, R., Jankowski, A.
• Format: Article
• Language: English
• Subjects: Absorption; Additives; Animals; Cellulose; Chromatography, High Pressure Liquid; Cream; Diffusion; Diffusion cells; Dissolution; Ear; Emulsions; Flavonoids; Flavonoids - administration & dosage; Flavonoids - metabolism; formulation skin care; Formulations; Gels; In vitro methods and tests; In Vitro Techniques; penetration enhancer; Polyethylene glycol; Polyethylenes; Propylene; Propylene glycol; Quercetin; Retention; Semisolids; Skin; Skin - metabolism; skin barrier; skin delivery; Skin tests; Spectrophotometry, Ultraviolet; Swine
• ISSN: 0142-5463; 1468-2494
• DOI: 10.1111/ics.12395

Objective To assess the effect of two different additives (propylene glycol (PG) and polyethylene glycol 400 (PEG 400)) on release and in vitro skin retention of quercetin and chrysin from semisolid bases (amphiphilic creams and acidic carbomer gels). Methods For obtaining semisolid formulations, flavonoids were pre‐dissolved in the liquid (PG or PEG 400) or directly suspended in the semisolid base. Three chrysin formulations (‘cream 0’, ‘PG‐cream’ and ‘PEG 400‐cream’) and five quercetin formulations (‘cream 0’, ‘PG cream’, ‘PEG 400 cream’, ‘gel 0’ and ‘PG gel’) were prepared. The release studies were carried out in Franz diffusion cells by means of a cellulose membrane. The porcine ear skin was used in in vitro skin retention studies. Results The dissolution was a prerequisite to increase the release rates of tested flavonoids from obtained semisolid formulations. The cumulative amount of chrysin released after 6 h from ‘PEG 400 cream’ containing partly dissolved form of that flavonoid was higher than that from ‘cream 0’ or ‘PG cream’ containing its suspended form. The formulations containing quercetin dissolved in PG (‘PG cream’, ‘PG gel’) or PEG 400 (‘PEG 400 cream’) exhibited higher release rates of that flavonoid than corresponding semisolid suspensions (‘cream 0’ or ‘gel 0’). The effects of both liquid additives (PG and PEG 400) on the cumulative amount of quercetin released after 6 h were comparable. However, there was no correlation between the release rate and the skin retention. The amounts of the flavonoids found in the skin were strongly affected by the type of the used solvent. While PG increased the skin retention of both flavonoids, PEG 400 had no effect on chrysin skin retention and delayed quercetin skin absorption. Conclusion The proper choice of the solvent added to the semisolid base is crucial for enhanced skin delivery of the tested flavonoids. PG is more efficient absorption promoter than PEG 400 of both chrysin and quercetin. Résumé Objectif Évaluer l'effet de deux additifs différents (propylène glycol (PG) et polyéthylène glycol 400 (PEG 400)) sur la libération et la rétention cutanée in vitro de la quercétine et de la chrysine à partir de bases semi‐solides (crèmes amphiphiles et gels carbomères acides). Méthodes pour l'obtention des formulations semi‐solides, les flavonoïdes ont été pré‐dissous dans le liquide (PG ou PEG 400) ou directement en suspension dans la base semi‐solide. Trois formulations de chrysine («crème 0», «crème