Characterization of Hydrogels Containing Mandelic Acid Nanoemulsions and Different Essential Oils

Hydrogels are polymeric matrices having minimal toxicity, elastomeric consistency and high permeability, making them useful for the controlled release of actives. These products have extensive applications in the cosmetic area as drug vehicles. In this work, hydrogels were prepared with concentrations of Polyvinylpyrrolidone (PVP, 7.5%wt), Polyethylene glycol (P.E.G., 3%wt) and agar (1%wt) containing pseudoboehmite, mandelic acid with essential oil of Palmarosa, Lavender, Geranium and/or Lemongrass, subjected to 25 kGy radiation. The hydrogels were characterized using sensory analysis, isothermal dehydration with air entrainment and dehydration as a function of time. The results showed that the hydrogels containing different essential oils undergo dehydration as a function of time from 2% to 4%. The hydrogel containing Lavender essential oil showed 23% isothermal dehydration with air entrainment. As for the degree of satisfaction, the hydrogel with Lemongrass essential oil was the most suitable for the consumer market. Therefore, it is concluded that these analyses are relevant for cosmetic development.

Keywords:
pseudoboehmite; nanoemulsions; mandelic acid; essential oils