In vitro skin permeation study of medium-chain triacylglycerols (MCTs) / Zulkefli Mohamad

Many approaches have been used to increase the low permeability of the drug through the skin. One of them is by including permeation enhancers such as medium chain triacylglycerols (MCTs). These agent, reversibly alter the barrier resistance of the stratum comeum and allow the drug to permeate into the viable epidermis and systemic circulation. This study was carried out to evaluate the in vitro skin permeation of n-tocopherol, the model antioxidant in different MCTs namely virgin coconut oil (VCO) and structured virgin coconut oil (SVCO) creams. VCO is rich in lauric acid (60%) while SVCO which was produced by lipase catalysed acidolysis of caprylic acid and VCO contains highly in caprylic acid (60%). The skin permeation of u-tocopherol in the formulation was measured for 24 hour test through the finite dose technique using Franz diffusion cells. The 24 hour skin permeation of a­ tocopherol using synthetic membrane shows greater release rate in SVCO cream than the VCO cream with the maximum flux rate of 0.57 mg/cmvh and 0.4 mg/cm/h, respectively. The in vitro skin permeation study using rat's skin showed no absorption profile, however results of the stratum corneum and viable epidermis extracts showed higher amount of n-tocopherol in the skin applied with the SVCO cream compared to the VCO cream. Amounts of n-tocopherol recovered from the stratum comeum and viable epidermis in VCO and SVCO creams were 93.43 µg/ml, 121.18µg/ml, 99 .3 7µg/ml and 151.01µg/ml respectively. These results revealed that triacylglycerols (TAGs) carbon chain lengths influence the permeation of the