Drug release and biodegradability of electrospun cellulose nanocrystal reinforced polycaprolactone

In this paper, high molecular weight cellulose was used as the starting material for the synthesis of cellulose nanocrystal (CNC). Different analysis techniques such as FTIR, XRD, TGA, DLS, and AFM were used to characterize CNC synthesis. The synthesized CNC was incorporated in polycaprolactone solution and nanofibers were prepared under different conditions. Production conditions were optimized based on the diameter of nanofibers using response surface methodology (RSM). Based on our results, the optimal condition is electrospinning of 16% PCL polymer solution at 17 kV and a 0.9 ml/h feed rate, which yields nanofibers with a diameter of 233 nm. The effects of CNC content on morphological, mechanical and thermal properties were investigated. Results also showed that CNC incorporation in PCL nanofibers enhances biodegradability. SEM, DSC, tensile, and biodegradability results showed that the nanofibers prepared from PCL solution containing 1% CNC have optimal mechanical and degradation behaviors. We also studied and modeled release of tetracycline from nanofiber mats, based on the assumption of rate limiting diffusion from the nanofibers, with a fraction of release delayed by drug sequestration. Results showed that the final drug release is decreased in CNC-incorporated nanofibers.