Objective: Grape seed oil (GSE) from Vitis vinifera L. has a high linoleic acid content, which plays a role in the skin moisturizing. However, linoleic acid is a liquid form and easily oxidized. The aims of this research were to prepare the microcapsules of GSE using ethylcellulose as coating polymer, and to formulate the gel containing the GSE microcapsules. Method: GSE microcapsules were prepared by solvent evaporation method with ethylcellulose in the ratio of 1:1, 1:2, 1:3 and 1:4 based on the amount of oil and polymer ratio. The produced GSE microcapsules were characterized such as the morphology, entrapment efficiency, particle size, and swelling index. The best microcapsules were formulated into a gel dosage form, and then evaluated. Results: The results showed that the microcapsules had a spherical shape and exhibited no pores, with the entrapment efficiency was in the range of 45.81 to 93.87%. The mean volume diameters of F1, F2, F3, and F4 microcapsules were 83.58 nm, 129.40 nm, 151.15 nm and 202.74 nm, respectively. The microcapsules showed the swelling index in the range of 49-73%. Furthermore, the gel containing 2% GSE microcapsules showed a good appearance and viscosity of 10,800 cps with plastic flow property. Conclusion: The F4 microcapsules of GSE, which the ratio of GSE and ethylcellulose was 1:4, was the best microcapsules with the entrapment efficiency of 93.87%. The GSE microcapsules that was incorporated into a gel formulation would be an interesting cosmetic product for skin moisturizer.
Key words: Ethylcellulose, Grape seed oil, Linoleic acid, Microencapsules, Solvent evaporation.