Abstract
Hormones are chemical substances which transmit a message as a signal within a physiological system between the place where they are secreted and the place of their receptors where they have the biological action. In the last decades the number of studies on phytohormones has increased continuously. In this study, polyurethane microstructures with and without brassinolide were synthesized in order to assess the release rate. Two different types of drug carriers were obtained (ether- and ester-based microstructures) and the evaluations were done by using two different methods: the measurement of microstructures’ size and the determination of free brassinolide concentration. The results suggest that ester-based polyurethane microstructures degrade faster and the two methods present very similar results. Keywords: brassinolide, drug carrier, DSC, polyurethane, UV-Vis, zetasizer