ABSTRACT
OBJECTIVE: To investigate the effect of natural and synthetic borneol on the transdermal absorption of emodin. METHODS: The supplying and receiving solutions containing emodin were selected from the abdominal skin of mice in vitro, and the samples were analyzed by HPLC. The cumulative permeability, permeability rate and permeability enhancement factor were used as the evaluation indexes of the permeability enhancement effect. RESULTS: The saline containing 1% Tween 80-80% ethanol and 60% ethanol could increase the solubility of emodin to 648 μg•mL -1 and obtain conditions of leaking trough. The penetration rate of emodin was 648 μg•mL - 1 > 569 μg•mL -1 > 457 μg•mL -1 in the range of concentration. The penetration enhancement effect of synthetic borneol was 2% > 4% > 1% > blank control group > 3% and 5%, and the steady-state permeation rates of 2% natural borneol (15.90 μg•cm- 2•h - 1 ) were higher than those of 2% synthetic borneol(12.44 μg•cm-2•h-1). CONCLUSION: Natural borneol and synthetic borneol can promote the transdermal penetration of emodin, which is limited by their concentration. This provides an experimental basis for the selection of emodin transdermal enhancers.