Eudragit-based electrospun nanofibers for improving the solubility and permeability of cefditoren pivoxil: in-vitro, ex-vivo and histological assessment

The dual solubility enhancement effect of nanofiber technology and pH-sensitive Eudragit L100-55 and S100 on class IV Cefditoren pivoxil (CEF) was studied. Nanofibers of different drug-polymer ratios were prepared. In-vitro characterization of CEF-loaded nanofibrous systems was performed through scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and in-vitro drug release. SEM showed that the nanofiber prepared using S100 is thicker than that prepared using L100-55 without entrapping any drug crystals in the polymer matrix. DSC scan proved the drug was entrapped in its molecular state due to the disappearance of the drug's crystallinity. The drug release profile indicated that all nanofiber formulations exhibited a considerably higher dissolution rate than free drug in the following order ED L100-55 > ED S100 > pure drug. Drug permeability enhancement was studied by using the modified non-everted sac technique. The drug permeability agrees in the same order as the drug release profile. Histology of the intestinal segment after 90 min showed the appearance of nanoparticles in the cytoplasm of the enterocytes, indicating that the drug absorption mechanism is mainly transcellular. Histology of the intestinal segment at the end of the experiment showed a highly significant increase in the mean length of the intercellular space of EL100-55 (p < 0.001), indicating drug enhancement via the paracellular pathway.