The modelling and biopharmaceutical evaluation of cellulose–based hydrogels with an aqueous propolis extract

The aim of work: To model cellulose–based hydrogels with an aqueous propolis extract, to optimize the experimental hydrogels and to justify their quality in biopharmaceutical researches. Main tasks: To make an aqueous propolis extract and to estimate its qualitative and quantitative compositions; to make a cellulose–based hydrogels with an aqueous propolis extract and to evaluate their quality, by determining its viscosity, pH and in vitro release; to optimize cellulose–based hydrogels with an aqueous propolis extract and to evaluate the optimal composition quality, by determining its viscosity, pH and in vitro release. Methods: The validated HPLC method was used to identify and to quantify propolis compounds. Viscosity of cellulose–based hydrogels was measured in room temperature by vibro viscosimeter and pH was measured by pH–meter. In vitro release studies were performed using the modified Franz type diffusion cells. Results: Modelled cellulose–based hydrogels with an aqueous propolis extract pH values were in the range of 4,2±0,04–6,07±0,01. The viscosity varies from 0,14±0,02 Pa·s to more than 11 Pa·s. Tight consistency hydrogels were obtained by using 5 percents of KMC–sodium, 11 percents of HEC, 13 percents of HPMC and 17 percents of MC. The maximum amount of released phenolic compounds was obtained from 11 percents HEC hydrogel (56,43 μg/cm2), compared with others tight consistency hydrogels which were made from one type of cellulose. From liquid consistency hydrogels, the highest amount of released phenolic compounds showed 7 percents HPMC and 6 percents HEC hydrogels: 85,14 μg/cm2 and 81,98 μg/cm2, respectively. From the optimal composition cellulose–based hydrogel released 72,12±2,71 μg/cm2 phenolic compounds. It is 148–162 percents more than tight consistency, individual components of the optimal composition hydrogels: 5 percents KMC–sodium and 13 percents HPMC. Conclusions: Cellulose–based hydrogels with an aqueous propolis extract were suitable to carry them on the skin. The most released phenolic compounds were determined from liquid consistency hydrogels, compared with all cellulose–based hydrogels. The optimal hydrogel composition released more phenolic compounds, compared with the individual components hydrogels. The optimal cellulose–based hydrogel composition released the highest amount of phenolic compounds, compared with the others tight consistency cellulose–based hydrogels