Study on Preparation and Transdermal Permeation of Lornoxicam Ethosomal Gel in Vitro

OBJECTIVE To prepare lornoxicam( LN) ethosomal gel and to study its transdermal permeation in vitro. METHODS The LN ethosomes were prepared by ethanol injection method. The formulation and the preparation method of ethosomes were optimized by orthogonal experiment using encapsulation efficiency as index. The morphology,particle size,Zeta potential and entrapment efficiency were evaluated,and the carbomer was added as the base for the preparation of the ethosomal gel. The penetration experiments of LN ethosomal gel through mouse skin were performed by Franz's cell. The concentration of LN was determined by HPLC. The cumulative penetration amount,steady penetration rate and the skin deposition of the drug were calculated. RESULTS The obtained ethosomes were spherical,the mean size and Zeta potential were( 385. 6 ± 59. 2) nm and( – 23. 49 ± 2. 38) mV,respectively. The mean entrapment efficiency of LN in ethosomes was( 73. 44 ± 1. 35) %. The LN ethosomal gel had a translucent yellow viscous colloidal appearance. The steady penetration rate of LN from ethosomal gel( 2. 81 μg·cm- 2·h- 1) was 12. 77,3. 51 and 2. 60 times higher than that from suspensions,gel and hydroethanolic suspensions of LN,respectively. The skin deposition of the drug at the end of the experiment was statistically greater from the ethosomal gel than from other control groups. CONCLUSION The gel is feasible in preparation technique,stable and controllable in quality and can improve transdermal penetration and increased the LN amount retain in the skin significantly.