Encapsulation of thyme oil into microsponges: preparation, characterization and in vitro evaluation

Thyme essential oil (TEO) is a prominent essential oil reported to have diverse properties and biological activities including anti-inflammatory. This research aims to encapsulate TEO in prepared microsponges for the purpose of controlled drug delivery and reduce the frequency of drug administration by enhancing its bioavailability. For the preparation of TEO loaded microsponges, the quasi-emulsion diffusion technique was used by employing dichloromethane as solvent, polyvinyl alcohol as a stabilizer and ethyl cellulose as polymer. The formulation variables such as altering the concentration of PVA and EC were used for optimization and characterized by FTIR, SEM and evaluated for particle size, in vitro drug release and entrapment efficiency and further subjected for in vitro anti-inflammatory activity. results showed that all the dispersions were in the micro-size range with good entrapment efficiency and release profile. The percent inhibition of protein denaturation by TEO loaded microsponges was found within the significant range at various concentrations.