Solid lipid particles for improved dermal delivery of virgin coconut oil

Abstract

Coconut oil has been recognized as a health oil in Ayurverdic medicine. Virgin Coconut Oil (VCO) is unique because it has a high degree of saturated fats, medium chain triglycerides, antioxidant activity and antimicrobials property. These factors make VCO a suitable lipophilic active ingredient in skin care products. VCO is usually extracted from well matured and fresh coconut through specialized process and is prepared in such a way that does not damage its natural structure or nutrition. Solid Lipid Particles (SLPs) is a novel delivery system of lipophilic functional cosmetic active ingredients. In this work, formulation, characterization and efficacy of VCO-SLPs have been studied. VCO-SLPs were prepared using ultrasonification of molten stearic acid and virgin coconut oil in an aqueous solution. From screening experiments, the best formula for VCO-SLPs was 1.78% Tween 80, 0.73% soy lecithin, 10% stearic acid, 5% VCO and 82.5% distilled water. Ultrasonicating was performed at several power intensities and different exposure times. The particle sizes of VCO-SLPs obtained were ranged from 0.608 µm to 44.265 µm. The zeta potentials of all the particles were from -43.2 mV to -47.5 mV showing that the particles obtained have good stability. The cumulative permeation of the VCO-SLPs range from 3.83 µg/cm2 to 3.59 µg/cm2 for VCO-SLPs in the range of 0.608 µm to 39.255 µm. VCO-SLPs with the particle size of 0.608 µm was chosen for subsequent study. Double blind skin evaluation test was conducted to analyze the performance of the VCO-SLPs incorporated moisturizing lotion. Moisturizing lotion incorporated with VCO-SLPs was found to increase skin hydration and skin elasticity by 24.8% and 2.60% respectively from day 0 to day 28. This shows that solid lipid particles has the potential to be utilized as a carrier for improved dermal delivery of VCO.