Research of complex of Сalendula officinalis extract–hydrogel for application in cosmeceuticals

Abstract

The complexes Calendula officinalis extract–hydrogel were prepared and investigated, which are intended for the use in cosmeceuticals. The hydrogel matrix was fabricated based on the copolymers of polyvinylpyrrolidone (PVP) with 2-hydroxyethyl methacrylate (HEMA) with different content of monomeric blocks, namely at the weight ratio of HEMA:PVP=60:40, 70:30, 80:20, and 90:10. The physicochemical characteristics of the obtained hydrogels were determined as follows: water content 48–69%, the degree of swelling 1.19–1.35, conditional porosity 53–84%, elasticity 82–89%, and pure plasticity 11–18%. Ethanol extract of Calendula officinalis was obtained by infusion, and the content of flavonoids was determined. The sorption capacity was measured and the kinetics of hydrogel swelling and extracts desorption from the complex was studied. The effects of hydrogel composition and thickness on the complex sorption capacity were studied. It was stated that the degree of swelling increases with increasing the PVP content in the original composition, therefore the hydrogel with the composition HEMA:PVP=80:20 seems to be the most optimal sample with enhanced sorption and desorption properties. The rate of release also depends on the content of PVP in the original composition and the content of pores, which are remained after washing. It was established that the best sorption of the extract and faster desorption are observed at the hydrogel matrix thickness of 1 mm. The study of flavonoid content in the obtained complexes and sorption/desorption processes revealed rapid sorption and desorption within 24 h, which is sufficient for the development of cosmeceutical mask on the basis of the investigated complexes.