Electrospun bi-layer Carboxymethyl cellulose/polyvinyl alcohol/polycaprolactone nanofibers: Fabrication, degradation, and phenytoin release kinetics

Carboxymethyl cellulose (CMC), polyvinyl alcohol (PVA), and polycaprolactone (PCL) were used to fabricate PNCMC and PNPCL-CMC nanofibers via electrospinning. PVA solutions at concentrations of 5, 6, 10, and 15% \(\:\left(w/v\right)\), and CMC solutions at concentration of 1 and 2% \(\:\left(w/v\right)\) were mixed with different volume ratios of PVA:CMC (1:1, 4:6, 3:7, 6:4, and 7:3). The 10% \(\:\left(w/v\right)\) PVA mixed with 1% \(\:\left(w/v\right)\) CMC at a 6:4 ratio yielded the best electrospinning performance. The addition of glutaraldehyde to the solutions improved fiber uniformity by promoting cross-linking. A bi-layer PNPCL-CMC nano-composite was subsequently developed by adding the PNCMC onto electrospun PCL nanofibers. The active pharmaceutical ingredient of phenytoin sodium was added to the polymer solution and electrospun to prepare drug-loaded nanofibers. The average fiber diameters were reported in the range of 100 to 500 nm. The degradation and swelling ratio of each layer were studied independently. After 30 days, 93.6% of PNCMC and 33.7% of PNPCL were degraded in phosphate buffered saline solution (pH = 7). The maximum swelling ratio for PNCMC (311.9%) was observed after 7 days, whereas the maximum swelling ratio for PNPCL (105%) was reported after 5 days. According to contact angel results, the bi-layer composite of superhydrophilic CMC and hydrophobic PCL nano-fibers offering high potential for wound dressing. Phenytoin release kinetics were evaluated using 7 models: zero-order, first-order, Higuchi, Hixson-Crowell, Korsmeyer-Peppas, and Baker-Lonsdale and the results were analyzed by comparing R ² and Akaike information criterion (AIC). The Baker-Lonsdale model provided the best fit, with R ²  = 0.9822 and AIC=-34.8275, for phenytoin release from PNPCL-CMC.