Carboxymethyl Chitosan Nano-Fibers for Controlled Releasing 5-Fluorouracil Anticancer Drug

In the present study, the pH responsive electrospun carboxymethyl chitosan nanofibers were prepared via electrospinning method and cross-linked with glutaraldehyde vapor for various times up to 48 h. The controlled release of 5-Fluorouracil (5-FU) from single layer and trilayered nanofibers (5-FU in the middle layer) was compared to obtain a sustained delivery system of 5-FU anticancer drug. The release of 5-FU from nanofibers was investigated at 37 degrees C under acidic pH (pH 5.5) and physiological pH (pH 7.4). The release data were fitted by zero-order, Higuchi and Korsmeyer-Peppas pharmacokinetic equations to determine the 5-FU release mechanism from nanofibers. Tri-layered nanofibers exhibited the sustained delivery of 5-FU without initial burst release during 168 and 216 h at pH=5.5 and 7.4, respectively. The initial burst release followed by sustained release of 5-FU from single layer cross-linked carboxymethyl chitosan nanofibers occurred during 48 and 60 h. The "n" constant of Korsmeyer-Peppas equation indicated the non Fickian diffusion of 5-FU from single layer nanofibers at both pH values of 5.5, pH 7.4 and tri-layered nanofibers at pH 5.5. Whereas, the Fickian diffusion of 5-FU was occurred from tri-layered nanofibers at pH 7.4. The obtained results indicated the high capability of tri-layered nanofibers for controlled release of 5-FU compared to single layer nanofibers.