Sustainable encapsulation of lipophilic fragrances using biodegradable sodium alginate for cosmetic applications

The encapsulation of lipophilic compounds for use in the cosmetic, food, and detergency industries is an area of growing interest. However, most current strategies rely on non-biodegradable materials, often classified as microplastics, which pose significant environmental risks. To address these issues, alternative encapsulation methods using biodegradable materials are being developed. Despite their potential, these methods have yet to demonstrate efficacy or economic feasibility comparable to conventional encapsulation systems. To overcome these challenges, a novel strategy has been developed for the encapsulation of lipophilic compounds, such as fragrances, using sodium alginate (SA). This approach involves the formation of an oil-in-water nanoemulsion via the Phase Inversion Composition method, with polysorbate 80 serving as the surfactant. The process is followed by the internal gelation of SA and subsequent dispersion to generate the final microcapsules. The formulation was optimized by varying the ratios of surfactant, oil, and aqueous phases in the nanoemulsion. Characterization techniques, including Dynamic Light Scattering, Gas Chromatography–Mass Spectrometry, and Thermogravimetric Analysis, confirmed successful encapsulation (average of 81 %, up to 97 % for one fragrance). The formulations demonstrated prolonged release profiles, with the scent remaining detectable for up to 30 days. An organoleptic study further revealed that encapsulated fragrances retained higher perceived intensity over time compared to their non-encapsulated counterparts. Moreover, the microcapsules exhibited excellent long-term stability within a conditioner matrix, maintaining their fragrance load for four months. This work represents a significant advancement in the development of environmentally friendly encapsulation methods for lipophilic compounds, offering promising applications in the cosmetic industry.