ABSTRACT
Objective: To optimize the two types of colchicine ethosome patches using uniform design and to investigate their in vitro release, transdermal properties, stability, and stimulus. Methods: Two kinds of colchicine ethosomes made of soybean lecithin (SL) and hydrogenated phosphatidy (HP) were prepared using injection method. By the DPS 7.0 sotfware, the uniform design was used to optimize the patch components of colchicines, polyacrylic resin IV, succinic acid, triethyl citrate, and azone in patch pressure-sensitive adhesive, with its initial adhesion and hold tack as indexes. The colchicine ethosomes patches of SL and HP were prepared, respectively. The automated dissolution test analyzer and improved Franz diffusion cell were adopted to compare the in vitro release and transdermal properties of the two types of colchicine ethosomes patches, respectively. Moreover, the preparation stability under different light, humidity, and high temperature conditions was studied, and the skin irritation test for rabbits was carried out. Results: The optimized colchicine ethosome patches by the uniform design adhere with the viscous standards in Chinese Pharmacopeia 2010. The in vitro release of the three types of patches were fitted with the Higuchi equation and their release rates increased in turn, respectively, which were (3.1331 ± 0.3272), (2.8724 ± 0.3481), and (2.3802 ± 0.2134) μg/(cm2·h1/2). Their in vitro transdermal releases were fitted with the zero-class equation and increased in turn, respectively, which were (0.9390 ± 0.0731), (0.8775 ± 0.0908), and (0.6167 ± 0.0816) μg/(cm2·h). During the storage, the HP patches had better stability than the SL patches, especially with the stable color. In the skin irritation test for rabbits, there was no erythema and oedema reactions in 48 h. Conclusion: The HP patches have obviously higer in vitro release rate and transdermal rate, and for its better stability of preparation, the HP patches are superior to the SL ones.