Aim: To survey the morphology and size distribution of silymarin microemulsion, to investigate the absorption of silymarin microemulsion in rat intestine compared with the absorption of silymarin micelle in rat Jejunum.
Methods: The intestine in rats was canulated for in situ recirculation.
Results: The absorption rate constants (Ka) of silymarin microemulsion at the entire intestine, ileum jejunum, duodenum and colon were 6.22 x 10(-2), 2.27 x 10(-2), 1.9 x 10(-2), 1.9 x 10(-2), 1.05 x 10(-2) and 0.43 x 10(-2) h(-1), respectively. The absorption rate constants of two kinds of silymarin micelle at jejunum were 0.36 x 10(-2), 0.65 x 10(-2) h(-1).
Conclusion: Silymarin microemulsion was well absorbed at the middle and lower segments of intestine in rats. The absorption was a first-order process with the passive diffusion mechanism.