[In situ rat intestine absorption of paclitaxel-loaded solid lipid nanoparticles modified with cell-penetrating peptides].

To investigate the rat intestinal absorption of stearic acid-octaarginine (SA-R8) modified solid lipid nanoparticles containing paclitaxel (SA-R8-PTX-SLN), compared with the commercially available preparation of PTX (Taxol) and PTX-loaded solid lipid nanoparticles (PTX-SLN), the in situ intestinal absorption of SA-R8-PTX-SLN was investigated by means of single-pass rat intestinal perfusion technique. The absorptions of the preparations were investigated at different intestinal segments, different drug concentrations and in the presence of P-glycoprotein inhibitor (verapamil). The results showed that PTX could be absorbed at each intestinal segment and the three preparations all showed maximum absorptions at the duodenum. The cumulative absorptions of three preparations at each intestinal segment appeared SA-R8-PTX-SLN > PTX-SLN > Taxol (P < 0.05). SA-R8-PTX-SLN showed a liner absorption manner at the duodenum in the examined drug concentration range. The cumulative absorptions of Taxol and PTX-SLN were significantly promoted after the addition of P-glycoprotein inhibitor (verapamil) into the preparation (P < 0.05), but absorption of SA-R8-PTX-SLN existed no significantly difference compared with the preparation without verapamil (P > 0.05). SA-R8 and SLN might both effectively improve the oral absorption of PTX in the intestinal tract.