RESUMO
<p><b>OBJECTIVE</b>To investigate effect of particle size on oral absorption of silymarin-loaded solid lipid nanoparuicles.</p><p><b>METHOD</b>Solid lipid nanoparticles (SLN) of various sizes (150 nm, 500 nm and 1000 nm) using Compritol 888 ATO as the material and silymarin (SM) as a model drug were prepared. Silybinin concentration in plasma of rats were determined by RP-HPLC with UV detector. The main pharmacokinetic parameters were calculated by 3p97.</p><p><b>RESULT</b>Results showed that the AUC of 150 nm SLN was 2.08 fold that of 500 nm SLN and 2.54 fold of 1000 nm SLN treated orally to rats (P < 0.05). The oral bioavailability of 150 nm SLN was remarkably higher than the other two size SLN.</p><p><b>CONCLUSION</b>This has important implications in designing of SM-SLN as a new oral drug delivery system.</p>