Development of Transdermal Patch Comprising Centella Asiatica Extract
The purpose of this study was to develop matrix-type transdermal systems containing Centella asiatica extract for treatment of varicose veins by using various polymers such as ethylcellulose (EC), methylcellulose (MC), hydroxypropylmethylcellulose (HPMC), polyvinylpyrolidone (PVP) and hydroxyproply cellulose (HPC-H, HPC-M and HPC-L grades) at various concentrations (0.75%, 1.00%, 1.25%, 1.50%, 1.75% and 2.00%) and using 30% of propylene glycol (PG), diethyl phathalate (DEP), dibutyl phathalate (DBP), glycerine, polyethylene glycol (PEG) 400 as plasticizers. Centella asiatica extract at 7% of solid content of the formulation was added to the matrix formulation prior to pouring on backing layer which was prepared by using either EC as polymer and DBP as plasticizer or polyethylene wrap. It was found that the use of polyethylene wrap as backing layer, PG as plasticizer and HPC as matrix layer showed better appearance, flexibility and compatibility. It was also found that HPC-H and HPC-M showed high adhesion and stickiness. It was concluded that HPC at concentration of 1.75% and 2.00% could be formulated as satisfactory transdermal matrix-type patch for Centella asiatica extract.
S. Suttiruengwong and W. Sricharussin
K. Suwannachote and G. C. Ritthidej, "Development of Transdermal Patch Comprising Centella Asiatica Extract", Advanced Materials Research, Vols. 93-94, pp. 389-392, 2010