Encapsulation of geranyl cinnamate in polycaprolactone nanoparticles

• DOI: 10.1016/j.msec.2018.12.005
• Publication Date: 2018-12-04T12:18:22Z
• Authors: Micheli Zanetti; Laís Regina Mazon; Alessandra Cristi...; Luciano Luiz Silva; Pedro Henrique He...; Márcio Antônio Fiori; Débora de Oliveira
• Keywords: Staphylococcus aureus; Calorimetry, Differential Scanning; Drug Compounding; Polyesters; Temperature; Microbial Sensitivity Tests; 02 engineering and technology; Anti-Bacterial Agents; 3. Good health; Drug Stability; Cinnamates; Spectroscopy, Fourier Transform Infrared; Thermogravimetry; Escherichia coli; Nanoparticles; Colloids; Particle Size; 0210 nano-technology

Geranyl cinnamate is an ester derived from natural compounds that has excellent antibacterial properties but is susceptible to degradation in the presence of oxygen, light, heat, moisture and other aggressive agents, making it unstable. In this work, the encapsulation of geranyl cinnamate in polycaprolactone (PCL) nanoparticles and its antibacterial properties towards Escherichia coli and Staphylococcus aureus were investigated. PCL nanoparticles loaded with geranyl cinnamate were obtained by a miniemulsification/solvent evaporation technique resulting in spherical nanoparticles with an average diameter of 177.6 nm. TGA showed that geranyl cinnamate evaporation was retarded at 20 °C after encapsulation. Aqueous dispersions of geranyl cinnamate-loaded PCL nanoparticles stored at 4 °C presented good colloidal stability over 60 days. Minimum inhibitory concentration (MIC) tests showed that geranyl cinnamate was not released from the PCL nanoparticles in aqueous solution even after 72 h, requiring the use of a trigger (e.g. oil phase, lipase to degrade the polymer matrix) to release the active compound.