The effect of chamomile extract obtained in supercritical carbon dioxide conditions on physicochemical and usable properties of pharmaceutical ointments

The study investigated the effect of chamomile extract obtained in supercritical carbon dioxide conditions on the basic properties of pharmaceutical ointments. A total of five formulations were designed and prepared, differing in the weight ratio of sunflower oil to chamomile extract (5:0, 3.5:1.5, 2.5:2.5, 1.5:3.5 and 0:5). An increase in the concentration of chamomile extract was found to be accompanied by a decrease in hardness, adhesive power and flow limit. Based on viscosity measurements it was shown that ointments containing the hydrophobic plant extract under study were prone to larger drops in viscosity under the effect of the set shear rate. It was determined that from the viewpoint of ointment spreadability and application to the skin, the optimum concentration of chamomile extract for the studied formulations should be within the range of 1.5-2.5%. Furthermore, the addition of chamomile extract to ointments was found to give samples a yellow-green color. Green was observed to be the dominant color, and its saturation and shade varied for different formulations.