Polymeric encapsulation of natural bioactive compounds offers a promising strategy to enhance the stability and controlled release of volatile substances. In this study, eugenol was encapsulated into a low?density polymer matrix using sodium alginate as the encapsulating agent, forming a suspo-emulsion. Stable microemulsions (eugenol 10%, Tween 80/phospholipid-based emulsifier 2% m/m) were crosslinked with calcium ions under stirring speeds ranging from 200 to 4000 rpm. Alginate concentrations (0.1–2% m/m) significantly influenced the formation of microcarriers, with mean particle diameters (d43) ranging from 5 to 50 µm, decreasing with higher agitation energy. Optical microscopy confirmed the formation of three-dimensional hydrogel networks that immobilized eugenol droplets. At the same time, dynamic light scattering (DLS) analysis revealed stable nanoemulsions (<100 nm) with a negative zeta potential (–20 to –40 mV), attributed to the presence of phosphate groups from the emulsifier. Volatility assessments demonstrated a marked improvement in eugenol retention: the encapsulated compound exhibited a 60% reduction in volatilization over 24 hours compared to a rapid 50% loss within 10 minutes for free eugenol. This substantial decrease in volatilization is attributed to the reduced mobility of droplets within the densely crosslinked hydrogel matrix and the higher viscosity of the continuous phase, which effectively hinders the diffusion of volatile compounds. Accelerated stability tests (54 °C/14 days) further confirmed superior retention in crosslinked systems with 2% m/m alginate (85–90%) compared to non-crosslinked formulations (60–70%). The results support the potential of this suspo-emulsion-based system for the sustainable release of volatile substances, such as essential oils, across diverse applications including agriculture, cosmetics, and pharmaceuticals.
Comissão Organizadora
Pedro Alves da Silva Autreto
Comissão Científica
Ferramenta completa de submissão, avaliação e publicação de anais para eventos científicos.
